# dhcp.pm
#
# The dhcp plugin
package dhcp;
@ISA = qw(Exporter);
@EXPORT = qw(createPlugin
bootingCreateFiles
bootingCommands
execCreateFiles
execCommands
shutdownCommand
finalizePlugin);
###########################################################
# Modules no import
###########################################################
use strict;
use Net::Netmask;
use XML::DOM; # XML management library
use File::Basename; # File management library
use Switch;
use Socket; # To resolve hostnames to IPs
use XML::DOM::ValParser; # To check DTD
###########################################################
# Global variables
###########################################################
my $globalNode;
my $valid_fail;
###########################################################
# Subroutines
###########################################################
###########################################################
# createPlugin
#
# To be called always, just before starting procesing the scenario specification
#
# Arguments:
# - the operation mode ("t","x","d" or "P")
# - the plugin configuration file
#
# Returns:
# - an error message or 0 if all is ok
#
###########################################################
sub createPlugin {
my $self = shift;
my $mode = shift;
my $conf = shift;
my $error;
print "dhcp: $conf\n";
eval {
$error = &checkConfigFile($conf);
};
if ($@) {
$error = $@;
}
return $error;
}
###########################################################
# bootingCreateFiles
#
# To be called during "t" mode, for each vm in the scenario
#
# Arguments:
# - vm name
#
# Returns:
# - a hashname which keys are absolute pathnames of files in vm filesystem and
# values the the pathname of the file in the host filesystem. The file in the
# host filesytesm is removed after VNUML processed it, so temporal files in
# /tmp are preferable)
#
###########################################################
sub bootingCreateFiles {
my $self = shift;
my $vm = shift;
my %files;
my $type;
my $virtualmList = $globalNode->getElementsByTagName("vm");
my $longitud = $virtualmList->getLength;
for ( my $m = 0 ; $m < $longitud ; $m++ ){
my $virtualm = $virtualmList->item($m);
my $virtualm_name = $virtualm->getAttribute("name");
if ( $virtualm_name eq $vm ){
$type = $virtualm->getAttribute("type");
switch ($type) {
case "dhcp3" {
my $serverTagList = $virtualm->getElementsByTagName("server");
my $numservers = $serverTagList->getLength;
if ( $numservers == 1 ) {
# open filehandle to create /etc/dhcp3/dhcpd.conf file
my $server_file = "/tmp/$vm" . "_server.conf";
chomp( my $date = `date` );
open( SERVER, ">$server_file" ) or $files{"ERROR"} = "Cannot open $server_file file";
# server.conf file defaults
print SERVER "# server.conf file generated by dhcp.pm VNUML plugin at $date\n\n";
print SERVER "ddns-update-style none;\n";
print SERVER "default-lease-time 120;\n";
print SERVER "max-lease-time 120;\n";
#print SERVER "log-facility local7;\n\n";
# extract configuration from subnet blocks in dhcp_conf.xml
my $server = $serverTagList->item(0);
my $subnetTagList = $server->getElementsByTagName("subnet");
my $numsubnets = $subnetTagList->getLength;
for ( my $ns=0; $ns < $numsubnets ; $ns++ ) {
my $subnet = $subnetTagList->item($ns);
my $ipTagList = $subnet->getElementsByTagName("ip");
my $numip = $ipTagList->getLength;
# subnet declaration
my $ipTag = $ipTagList->item($0);
my $subnetmask = $ipTag->getAttribute("mask");
my $subnetbaseip = $ipTag->getFirstChild->getData;
my $block = new Net::Netmask("$subnetbaseip"."/"."$subnetmask");
my $baseip = $block->base();
my $mask = $block->mask();
print SERVER "subnet $baseip netmask $mask {\n";
# extract ip ranges in subnet
my $rangeTagList = $subnet->getElementsByTagName("range");
my $numranges = $rangeTagList->getLength;
for ( my $nr = 0; $nr < $numranges ; $nr++ ) {
my $rangeTag = $rangeTagList->item($nr);
my $firstTagList = $rangeTag->getElementsByTagName("first");
my $firstTag = $firstTagList->item(0);
my $firstip = $firstTag->getFirstChild->getData;
my $lastTagList = $rangeTag->getElementsByTagName("last");
my $lastTag = $lastTagList->item(0);
my $lastip = $lastTag->getFirstChild->getData;
print SERVER " range $firstip $lastip;\n";
}
# extract routers in subnet (if any)
my $routerTagList = $subnet->getElementsByTagName("router");
my $numrouters = $routerTagList->getLength;
if ( $numrouters > 0 ) {
print SERVER " option routers";
for ( my $nr = 0; $nr < $numrouters ; $nr++ ) {
if ( $nr > 0 ) {
print SERVER ",";
}
my $routerTag = $routerTagList->item($nr);
my $router = $routerTag->getFirstChild->getData;
print SERVER " $router";
}
print SERVER ";\n";
}
# extract dns in subnet (if any)
my $dnsTagList = $subnet->getElementsByTagName("dns");
my $numdns = $dnsTagList->getLength;
if ( $numdns > 0 ) {
print SERVER " option domain-name-servers";
for ( my $nd = 0; $nd < $numdns ; $nd++ ) {
if ( $nd > 0 ) {
print SERVER ",";
}
my $dnsTag = $dnsTagList->item($nd);
my $dns = $dnsTag->getFirstChild->getData;
print SERVER " $dns";
}
print SERVER ";\n";
}
# extract domain in subnet (if specified)
my $domainTagList = $subnet->getElementsByTagName("domain");
my $numdomains = $domainTagList->getLength;
if ( $numdomains == 1 ) {
my $domainTag = $domainTagList->item(0);
my $domain = $domainTag->getFirstChild->getData;
print SERVER " option domain-name \"$domain\";\n";
}
# end subnet declaration in configuration file
print SERVER "}\n\n";
# extract hosts in subnet (if any)
my $hostTagList = $subnet->getElementsByTagName("host");
my $numhosts = $hostTagList->getLength;
for ( my $nh = 0; $nh < $numhosts ; $nh++ ) {
my $hostTag = $hostTagList->item($nh);
my $hostname = $hostTag->getAttribute("name");
my $hostmac = $hostTag->getAttribute("mac");
my $hostip = $hostTag->getAttribute("ip");
# ignore unmatching host declarations
if ( $block->match($hostip) ) {
print SERVER "host $hostname {\n hardware ethernet $hostmac;\n fixed-address $hostip;\n}\n\n";
}
}
}
close(SERVER);
$files{"/etc/dhcp3/dhcpd.conf"} = $server_file;
}
my $relayTagList = $virtualm->getElementsByTagName("relay");
my $numrelays = $relayTagList->getLength;
if ( $numrelays == 1 ) {
# Build file /etc/default/dhcp3-relay.conf
my $relay_file = "/tmp/$vm" . "_relay.conf";
chomp( my $date = `date` );
open( RELAY, ">$relay_file" ) or $files{"ERROR"} = "Cannot open $relay_file file";
print RELAY "# relay.conf file generated by dhcp.pm VNUML plugin at $date\n";
print RELAY "SERVERS=\"";
my $relay = $relayTagList->item(0);
my $toserverTagList = $relay->getElementsByTagName("toserver");
my $numtoservers = $toserverTagList->getLength;
for ( my $nt = 0; $nt < $numtoservers ; $nt++ ) {
my $toserverTag = $toserverTagList->item($nt);
my $toserverData = $toserverTag->getFirstChild->getData;
print RELAY "$toserverData ";
}
print RELAY "\"\n";
close(RELAY);
$files{"/etc/default/dhcp3-relay"} = $relay_file;
}
my $clientTagList = $virtualm->getElementsByTagName("client");
my $numclients = $clientTagList->getLength;
if ( $numclients == 1 ) {
# Build file /etc/dhcp3/dhclient.conf
my $client_file = "/tmp/$vm" . "_client.conf";
chomp( my $date = `date` );
open( CLIENT, ">$client_file" ) or $files{"ERROR"} = "Cannot open $client_file file";
print CLIENT "# Configuration file for /sbin/dhclient, which is included in Debian's dhcp3-client package.\n";
print CLIENT "# client.conf file generated by dhcp.pm VNUML plugin at $date\n\n";
print CLIENT "send host-name \"<hostname>\";\n";
print CLIENT "request subnet-mask, broadcast-address, time-offset, routers, domain-name, domain-name-servers, domain-search, host-name, netbios-name-servers, netbios-scope, interface-mtu;\n";
print CLIENT "retry 10;\n";
close(CLIENT);
$files{"/etc/dhcp3/dhclient.conf"} = $client_file;
}
}else{
$files{"ERROR"} = "Your choice $type for $vm is not a recognized type (yet)\n";
}
}
}
}
return %files;
}
###########################################################
# bootingCommands
#
# To be called during "t" mode, for each vm in the scenario
#
# Arguments:
# - vm name
#
# Returns:
# - list of commands to execute in the virtual machine at booting time
#
###########################################################
sub bootingCommands {
}
###########################################################
# execVmsToUse
#
# To be called once during "x" mode
#
# Arguments:
# - seq command sequence
#
# Returns:
# - list of virtual machines where the command has effect
#
###########################################################
sub execVmsToUse {
my $self = shift;
my $seq = shift;
# Four lists are built, one is returned depending on the executed command
my @vm_list = ();
my @server_vm_list = ();
my @relay_vm_list = ();
my @client_vm_list = ();
my $virtualmList=$globalNode->getElementsByTagName("vm");
my $longitud = $virtualmList->getLength;
for (my $m=0; $m<$longitud; $m++){
my $virtualm = $virtualmList->item($m);
my $virtualm_name = $virtualm->getAttribute("name");
push (@vm_list,$virtualm_name);
my $serverTagList = $virtualm->getElementsByTagName("server");
my $numservers = $serverTagList->getLength;
my $relayTagList = $virtualm->getElementsByTagName("relay");
my $numrelays = $relayTagList->getLength;
my $clientTagList = $virtualm->getElementsByTagName("client");
my $numclients = $clientTagList->getLength;
if ( $numservers == 1 ) {
push (@server_vm_list,$virtualm_name);
}
if ( $numrelays == 1 ) {
push (@relay_vm_list,$virtualm_name);
}
if (!($numclients == 0)) {
push (@client_vm_list,$virtualm_name);
}
}
if ($seq eq "start" || $seq eq "restart" || $seq eq "stop" || $seq eq "dhcp-start" || $seq eq "dhcp-restart" || $seq eq "dhcp-stop") {
return @vm_list;
}elsif ($seq eq "dhcp-server-start"|| $seq eq "dhcp-server-stop" || $seq eq "dhcp-server-restart" || $seq eq "dhcp-server-force-reload"){
return @server_vm_list;
}elsif ( $seq eq "dhcp-relay-start"|| $seq eq "dhcp-relay-restart"|| $seq eq "dhcp-relay-stop"|| $seq eq "dhcp-relay-force-reload"){
return @relay_vm_list;
}elsif ($seq eq "dhcp-client-start"||$seq eq "dhcp-client-restart"||$seq eq "dhcp-client-stop"){
return @client_vm_list;
}else{
return ();
}
}
###########################################################
# execCreateFiles
#
# To be called during "x" mode, for each vm in the scenario
#
# Arguments:
# - vm name
# - seq command sequence
#
# Returns:
# - a hashname which kyes are absolute pathnames of files in vm filesystem and
# values the the pathname of the file in the host filesystem. The file in the
# host filesytesm is removed after VNUML processed it, so temporal files in
# /tmp are preferable)
#
###########################################################
sub execCreateFiles {
}
###########################################################
# execCommands
#
# To be called during "x" mode, for each vm in the scenario
#
# Arguments:
# - vm name
# - seq command sequence
#
# Returns:
# - list of commands to execute in the virtual machine after <exec> processing
###########################################################
sub execCommands {
my $self = shift;
my $vm = shift;
my $seq = shift;
my @commands;
my $type;
my $virtualmList = $globalNode->getElementsByTagName("vm");
my $longitud = $virtualmList->getLength;
for (my $m=0 ; $m<$longitud ; $m++) {
my $virtualm = $virtualmList->item($m);
my $virtualm_name = $virtualm->getAttribute("name");
if ( $vm eq $virtualm_name ) {
$type = $virtualm->getAttribute("type");
switch ($type) {
case "dhcp3" {
# recognized type
}
else {
unshift( @commands, "Your choice $type for $vm is not a recognized type (yet)\n");
}
}
my $serverTagList = $virtualm->getElementsByTagName("server");
my $numservers = $serverTagList->getLength;
my $relayTagList = $virtualm->getElementsByTagName("relay");
my $numrelays = $relayTagList->getLength;
my $clientTagList = $virtualm->getElementsByTagName("client");
my $numclients = $clientTagList->getLength;
switch ($seq){
case ["start","dhcp-start"]{
# Start server, relay and clients in the virtual machine, if any
unshift( @commands, "" );
if ( $numservers == 1 ) {
push( @commands, "/etc/init.d/dhcp3-server start" );
}
if ( $numrelays == 1 ) {
push( @commands, "/etc/init.d/dhcp3-relay start" );
}
if (!($numclients == 0)) {
unshift(@commands, "" );
my $client = $clientTagList->item(0);
my $ifTagList = $client->getElementsByTagName("if");
my $numif = $ifTagList->getLength;
for (my $ni=0; $ni<$numif ; $ni++) {
my $ifTag = $ifTagList->item($ni);
my $ifData = $ifTag->getFirstChild->getData;
if (!($ifData == 0)) {
push(@commands,"dhclient eth"."$ifData");
}
}
}
}
case ["restart","dhcp-restart"]{
# Restart server, relay and clients in the virtual machine, if any
unshift( @commands, "" );
if ( $numservers == 1 ) {
push( @commands, "/etc/init.d/dhcp3-server restart" );
}
if ( $numrelays == 1 ) {
push( @commands, "/etc/init.d/dhcp3-relay restart" );
}
if (!($numclients == 0)) {
unshift(@commands, "" );
my $client = $clientTagList->item(0);
my $ifTagList = $client->getElementsByTagName("if");
my $numif = $ifTagList->getLength;
for (my $ni=0; $ni<$numif ; $ni++) {
my $ifTag = $ifTagList->item($ni);
my $ifData = $ifTag->getFirstChild->getData;
if (!($ifData == 0)) {
push(@commands,"dhclient -r");
push(@commands,"killall dhclient");
push(@commands,"dhclient eth"."$ifData");
}
}
}
}
case ["stop","dhcp-stop"]{
# Stop server and relay in the virtual machine, if any
unshift( @commands, "" );
if ( $numservers == 1 ) {
push( @commands, "/etc/init.d/dhcp3-server stop" );
}
if ( $numrelays == 1 ) {
push( @commands, "/etc/init.d/dhcp3-relay stop" );
}
if (!($numclients == 0)) {
unshift(@commands, "" );
my $client = $clientTagList->item(0);
my $ifTagList = $client->getElementsByTagName("if");
my $numif = $ifTagList->getLength;
for (my $ni=0; $ni<$numif ; $ni++) {
my $ifTag = $ifTagList->item($ni);
my $ifData = $ifTag->getFirstChild->getData;
if (!($ifData == 0)) {
push(@commands,"dhclient -r");
push(@commands,"killall dhclient");
}
}
}
}
case ("dhcp-server-start"){
# Start the server in the virtual machine. Return error if there isn't any.
if ( $numservers == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp server. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-server start" );
}
}
case ("dhcp-relay-start"){
# Start the relay in the virtual machine. Return error if there isn't any.
if ( $numrelays == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp relay. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-relay start" );
}
}
case ("dhcp-client-start"){
# Start the clients in the virtual machine. Return error if there aren't any.
if ( $numclients == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp client. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift(@commands, "" );
my $client = $clientTagList->item(0);
my $ifTagList = $client->getElementsByTagName("if");
my $numif = $ifTagList->getLength;
for (my $ni=0; $ni<$numif ; $ni++) {
my $ifTag = $ifTagList->item($ni);
my $ifData = $ifTag->getFirstChild->getData;
if (!($ifData == 0)) {
push(@commands,"dhclient eth"."$ifData");
}
}
}
}
case ("dhcp-server-restart"){
# Restart the server in the virtual machine. Return error if there isn't any.
if ( $numservers == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp server. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-server restart" );
}
}
case ("dhcp-relay-restart"){
# Restart the relay in the virtual machine. Return error if there isn't any.
if ( $numrelays == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp relay. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-relay restart" );
}
}
case ("dhcp-client-restart"){
# Start the clients in the virtual machine. Return error if there aren't any.
if ( $numclients == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp client. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift(@commands, "" );
my $client = $clientTagList->item(0);
my $ifTagList = $client->getElementsByTagName("if");
my $numif = $ifTagList->getLength;
for (my $ni=0; $ni<$numif ; $ni++) {
my $ifTag = $ifTagList->item($ni);
my $ifData = $ifTag->getFirstChild->getData;
if (!($ifData == 0)) {
push(@commands,"dhclient -r");
push(@commands,"killall dhclient");
push(@commands,"dhclient eth"."$ifData");
}
}
}
}
case ("dhcp-server-stop"){
# Stop the server in the virtual machine. Return error if there isn't any.
if ( $numservers == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp server. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-server stop" );
}
}
case ("dhcp-relay-stop"){
# Stop the relay in the virtual machine. Return error if there isn't any.
if ( $numrelays == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp relay. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-relay stop" );
}
}
case ("dhcp-client-stop"){
# Start the clients in the virtual machine. Return error if there aren't any.
if ( $numclients == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp client. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift(@commands, "" );
my $client = $clientTagList->item(0);
my $ifTagList = $client->getElementsByTagName("if");
my $numif = $ifTagList->getLength;
for (my $ni=0; $ni<$numif ; $ni++) {
my $ifTag = $ifTagList->item($ni);
my $ifData = $ifTag->getFirstChild->getData;
if (!($ifData == 0)) {
push(@commands,"dhclient -r");
push(@commands,"killall dhclient");
}
}
}
}
case ("dhcp-server-force-reload"){
# Force reload of the server in the virtual machine. Return error if there isn't any.
if ( $numservers == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp server. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-server force-reload" );
}
}
case ("dhcp-relay-force-reload"){
# Force reload of the relay in the virtual machine. Return error if there isn't any.
if ( $numservers == 0 ) {
unshift( @commands, "$vm is not configured as a dhcp relay. Choose the appropriate virtual machine with flag -M name" );
}
else {
unshift( @commands, "" );
push( @commands, "/etc/init.d/dhcp3-relay force-reload" );
}
}else{
unshift( @commands, "\nYour choice \"$seq\" is not a recognized command (yet).\nAvailable commands: start, stop, restart, dhcp-start, dhcp-stop, dhcp-restart, dhcp-server-start, dhcp-server-stop, dhcp-server-restart, dhcp-server-force-reload, dhcp-relay-start, dhcp-relay-stop, dhcp-relay-restart, dhcp-relay-force-reload, dhcp-client-start.\n" );
}
}
return @commands;
}
}
}
###########################################################
# shutdownCommands
#
# To be called during "d" mode, for each vm in the scenario
#
# Arguments:
# - vm name
#
# Returns:
# - list of commands to execute in the virtual machine at shutdown time
#
###########################################################
sub shutdownCommands {
my $self = shift;
my $vm = shift;
my @commands;
my $type;
my $virtualmList = $globalNode->getElementsByTagName("vm");
my $longitud = $virtualmList->getLength;
for ( my $m = 0 ; $m < $longitud ; $m++ ) {
my $virtualm = $virtualmList->item($m);
my $virtualm_name = $virtualm->getAttribute("name");
if ( $vm eq $virtualm_name ) {
$type = $virtualm->getAttribute("type");
switch ($type) {
case "dhcp3" {
unshift( @commands, "" );
my $serverTagList = $virtualm->getElementsByTagName("server");
my $numservers = $serverTagList->getLength;
if ( $numservers == 1 ) {
push( @commands, "/etc/init.d/dhcp3-server stop" );
}
my $relayTagList = $virtualm->getElementsByTagName("relay");
my $numrelays = $relayTagList->getLength;
if ( $numrelays == 1 ) {
push( @commands, "/etc/init.d/dhcp3-relay stop" );
}
}
else {
unshift( @commands,"Your choice $type for $vm is not a recognized type (yet)\n");
}
}
}
return @commands;
}
}
#############################################################
# finalizePlugin
#
# To be called always, just before ending the procesing the scenario specification
#
# Arguments:
# - none
#
# Returns:
# - none
#
#############################################################
sub finalizePlugin {
}
#############################################################
#
# Checks existence and semantics in ospf conf file.
# Currently this check consist in:
#
# 1. Configuration file exists.
# 2. Check DTD.
# 3. IP tag contains mask attribute and data.
# 4. Area tag is unique and contains data.
#
#############################################################
sub checkConfigFile {
# 1. Configuration file exists.
my $config_file = shift;
open( FILEHANDLE, $config_file )
or { return "cannot open config file $config_file\n", };
close(FILEHANDLE);
# 2. Check DTD
my $parser = new XML::DOM::ValParser;
my $dom_tree;
$valid_fail = 0;
#eval {
local $XML::Checker::FAIL = \&validation_fail;
$dom_tree = $parser->parsefile($config_file);
#};
if ($valid_fail) {
return ("$config_file is not a well-formed DHCP plugin file\n");
}
$globalNode = $dom_tree->getElementsByTagName("dhcp_conf")->item(0);
return 0;
}
sub validation_fail {
my $code = shift;
# To set flag
$valid_fail = 1;
# To print error message
XML::Checker::print_error( $code, @_ );
}
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