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package dhcpd; |
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|
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=head1 dhcpd |
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|
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start with: |
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|
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perl -Ilib/PXElator -Ilib -Mdhcpd -e start |
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|
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based on L<http://www.perlmonks.org/index.pl?node_id=325248> |
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|
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=cut |
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|
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use strict; |
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use warnings; |
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|
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use autodie; |
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|
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use IO::Socket::INET; |
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use File::Slurp; |
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use Data::Dump qw/dump/; |
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|
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use lib '..'; |
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use Net::DHCP::Packet; |
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use Net::DHCP::Constants 0.67; |
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|
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use CouchDB; |
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use format; |
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|
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use server; |
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my $debug = server::debug; |
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|
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if ( ! $server::ip ) { |
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my $server_ip = `/sbin/ifconfig`; |
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$server_ip =~ s/^.+?addr:([\d\.]+).*$/$1/gs; |
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$server::ip = $server_ip; |
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} |
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|
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warn "server ip $server::ip range: $server::ip_from - $server::ip_to\n"; |
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|
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use client; |
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|
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sub client_mac_ip { |
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my ( $mac, $request_ip ) = @_; |
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|
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if ( ! $mac ) { |
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warn "W: no mac in requiest\n"; |
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return; |
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} |
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|
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my $conf = $server::conf; |
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mkdir $conf unless -e $conf; |
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|
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my $ip; |
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|
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if ( $ip = client::ip_from_mac( $mac ) ) { |
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print "RENEW $mac $ip\n"; |
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return $ip; |
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} elsif ( in_our_range( $request_ip ) ) { |
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$ip = client::next_ip( $mac ); |
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print "NEW $mac $ip\n"; |
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} else { |
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$ip = $request_ip; |
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client::save_ip_mac( $ip, $mac ); |
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warn "W: $ip our of server range $server::ip $server::netmask\n"; |
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} |
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|
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return $ip; |
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} |
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|
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use log; |
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use config; |
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use pxelinux; |
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use client; |
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|
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our $file; |
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our $transaction = 0; # FIXME predictible transaction numbers |
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|
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sub ip2bin { pack('C*', split(/\./, $_[0])) }; |
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sub in_our_range { |
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my $ip = shift; |
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return 1 if $ip eq '0.0.0.0'; |
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return 1 if ( |
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( ip2bin($ip) & ip2bin($server::netmask) ) |
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eq |
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( ip2bin($server::ip) & ip2bin($server::netmask) ) |
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); |
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} |
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|
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sub process_packet { |
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my $sock = shift; |
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|
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server->refresh; |
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|
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my $buf; |
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$sock->recv($buf, 1024); |
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my $size = 'empty'; |
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$size = length($buf) . ' bytes' if defined $buf; |
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|
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print "packet from ",$sock->peerhost,":",$sock->peerport," $size\n" if $debug; |
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return unless $buf; |
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|
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my $dhcp = Net::DHCP::Packet->new($buf); |
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|
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warn "recv: ", $dhcp->toString if $debug; |
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|
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$dhcp->comment( $transaction++ ); |
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|
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my $mac = substr($dhcp->chaddr(),0,$dhcp->hlen()*2); |
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my $ip = client_mac_ip($mac, $dhcp->ciaddr); |
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|
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my $hostname = $dhcp->getOptionValue(DHO_HOST_NAME); |
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print "$ip ", client::conf( $ip => 'hostname', default => $hostname ), " >> /etc/hosts\n"; |
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|
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my $audit = { mac => format::mac($mac), ip => $ip, hostname => $hostname, |
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options => { |
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map { |
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( $_ => $dhcp->getOptionValue( $_ ) ) |
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} @{ $dhcp->{options_order} } |
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}, |
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}; |
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|
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=for later |
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|
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my $user_class = $dhcp->getOptionValue(DHO_USER_CLASS()); |
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|
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if ( $user_class eq 'gPXE' ) { |
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$file = $gpxe_file; |
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} elsif ( ! $file ) { |
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$file = 'undionly.kpxe'; |
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} |
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|
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=cut |
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|
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config::for_ip( $ip ); |
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|
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my $packet = { |
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Op => BOOTREPLY(), |
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Hops => $dhcp->hops(), |
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Xid => $dhcp->xid(), |
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Flags => $dhcp->flags(), |
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Ciaddr => $dhcp->ciaddr(), |
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Yiaddr => $ip, |
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Siaddr => $server::ip, |
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Giaddr => $dhcp->giaddr(), |
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Chaddr => $dhcp->chaddr(), |
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File => $file, |
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DHO_DHCP_SERVER_IDENTIFIER() => $server::ip, # busybox/udhcpc needs it but doesn't request |
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}; |
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|
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my $options = { |
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DHO_SUBNET_MASK() => $server::netmask, |
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DHO_ROUTERS() => $server::ip, |
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DHO_DOMAIN_NAME() => $server::domain_name, |
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DHO_NAME_SERVERS() => $server::ip, |
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DHO_DOMAIN_NAME_SERVERS() => $server::ip, |
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DHO_HOST_NAME() => client::conf( $ip, 'hostname' ), |
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DHO_BROADCAST_ADDRESS() => $server::bcast, |
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# DHO_NTP_SERVERS() => '', |
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}; |
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|
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my @requested = split(/\s/, $dhcp->getOptionValue(DHO_DHCP_PARAMETER_REQUEST_LIST)); |
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warn "options ",dump( $options ), ' requested: ',dump( @requested ) if $debug; |
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|
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my @missing; |
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foreach ( @requested ) { |
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if ( defined $options->{$_} ) { |
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$packet->{$_} = $options->{$_}; |
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} else { |
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push @missing, $_; |
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} |
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} |
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|
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warn "W: options requested but missing: ",dump( @missing ),$/; |
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$audit->{requested} = [ @requested ]; |
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$audit->{missing} = [ @missing ]; |
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|
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foreach my $opt ( 'magic', 'config_file', 'path_prefix', 'reboot_time' ) { |
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my $DH0 = eval 'DHO_PXELINUX_' . uc $opt; |
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warn "DH0: $@" if $@; |
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my $v = eval "\$pxelinux::$opt"; |
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warn "v: $@" if $@; |
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next unless defined $v; |
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warn "pxelinux dhcp option $opt = $DH0 = $v\n" if $debug; |
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$packet->{ $DH0 } = $v; |
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} |
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|
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my $messagetype = $dhcp->getOptionValue(DHO_DHCP_MESSAGE_TYPE()); |
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|
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if ($messagetype eq DHCPDISCOVER()) { |
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$audit->{type} = 'discover'; |
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$packet->{Comment} = $dhcp->comment(); |
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$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPOFFER(); |
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} elsif ($messagetype eq DHCPREQUEST()) { |
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my $requested_ip = $dhcp->getOptionValue(DHO_DHCP_REQUESTED_ADDRESS()); |
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$audit->{type} = 'request'; |
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if ( $ip eq $requested_ip ) { |
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$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPACK(); |
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$packet->{DHO_DHCP_LEASE_TIME()} = 5 * 60; # 5 min |
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# $packet->{DHO_ROOT_PATH()} = '/exports/foobar'; |
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} else { |
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$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPNAK(); |
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$packet->{DHO_DHCP_MESSAGE()} = "Bad request, expected $ip"; |
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} |
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} elsif ($messagetype eq DHCPINFORM()) { |
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$audit->{type} = 'inform'; |
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} else { |
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$audit->{type} = sprintf('ignored %x', $messagetype); |
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} |
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|
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warn ">> $mac == $ip server: $server::ip", $file ? " file: $file\n" : "\n" if $debug; |
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$audit->{response} = $packet; |
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|
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$packet = new Net::DHCP::Packet( %$packet ); |
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warn "send ",$packet->toString() if $debug; |
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|
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if ( in_our_range( $ip ) ) { |
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my $buff = $packet->serialize(); |
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|
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my $reply = IO::Socket::INET->new( |
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LocalAddr => $server::ip, |
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LocalPort => 67, |
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Proto => "udp", |
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Broadcast => 1, |
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PeerAddr => '255.255.255.255', |
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PeerPort => 68, |
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Reuse => 1, |
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) or die "socket: $@"; |
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|
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$reply->send( $buff, 0 ) or die "Error sending: $!\n"; |
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} else { |
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$audit->{error} = "$ip our of our range $server::ip $server::netmask"; |
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} |
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|
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CouchDB::audit( $audit->{type}, $audit ); |
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|
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# system("arp -s $ip $mac"), |
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|
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} |
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|
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sub start { |
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|
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my $sock = IO::Socket::INET->new( |
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LocalPort => 67, |
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# LocalAddr => 'localhost', |
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# LocalAddr => '10.0.0.100', |
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LocalAddr => '0.0.0.0', |
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Proto => 'udp', |
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ReuseAddr => 1, |
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# PeerPort => getservbyname('bootpc', 'udp'), |
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Broadcast => 1, |
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Type => SOCK_DGRAM, |
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) or die "Failed to bind to socket: $@"; |
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|
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print "DHCP listen on ",$sock->sockhost,":",$sock->sockport,"\n"; |
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|
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CouchDB::audit( 'start', { addr => $sock->sockhost, port => $sock->sockport } ); |
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|
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while (1) { |
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process_packet $sock; |
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} |
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} |
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|
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warn "loaded"; |
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|
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1; |