use strict;
use warnings;
+use autodie;
+
use IO::Socket::INET;
-use Net::DHCP::Packet;
-use Net::DHCP::Constants;
+use File::Slurp;
use Data::Dump qw/dump/;
+use Net::Ping;
+use lib 'lib';
+use Net::DHCP::Packet;
+use Net::DHCP::Constants 0.67;
die "need to run $0 as root like this\nsudo $0\n" unless $< == 0;
my $debug = shift @ARGV;
-our ( $server_ip, $next_file );
-require "config.pl";
+our ( $file, $gpxe_file );
+our ( $ip_from, $ip_to ) = ( 10, 100 );
+
+our $server_ip = readlink 'conf/server.ip' if -l 'conf/server.ip';
+
+if ( ! $server_ip ) {
+ $server_ip = `/sbin/ifconfig`;
+ $server_ip =~ s/^.+?addr:([\d\.]+).*$/$1/gs;
+ warn "auto-configure server ip to $server_ip\n";
+} else {
+ warn "server ip $server_ip\n";
+}
my $sock = IO::Socket::INET->new(
LocalPort => 67,
Type => SOCK_DGRAM,
) or die "Failed to bind to socket: $@";
-my $_ip = 10;
-my $_mac2ip;
+
+my $addr = $ip_from;
sub client_ip {
my ( $mac ) = @_;
- my $ip = $_mac2ip->{$mac};
- return $ip if $ip;
+ my $conf = "conf/$server_ip";
+ mkdir $conf unless -e $conf;
+
+ if ( -e "$conf/mac/$mac" ) {
+ my $ip = read_file "$conf/mac/$mac";
+ print "$mac old $ip\n";
+ return $ip;
+ }
- $ip = $server_ip;
- $ip =~ s{\.\d+$}{.$_ip};
- $_mac2ip->{$mac} = $ip;
+ mkdir $_ foreach grep { ! -e $_ } map { "$conf/$_" } ( 'ip', 'mac' );
- $_ip++;
- if ( $_ip == 100 ) {
- warn "IP roll-over to 10\n";
- $_ip = 10;
+ my $p = Net::Ping->new;
+
+ my $prefix = $server_ip;
+ $prefix =~ s{\.\d+$}{.};
+ my $ip = $prefix . $addr;
+ while ( -e "conf/ip/$ip" || $p->ping( $ip ) ) {
+ $ip = $prefix . $addr++;
+ die "all addresses allocated!" if $addr == $ip_to;
}
+ write_file "$conf/mac/$mac", $ip;
+ if ( -l "$conf/ip/$ip" && readlink "$conf/ip/$ip" ne "$conf/mac/$mac") {
+ unlink "$conf/ip/$ip";
+ symlink "$conf/mac/$mac", "$conf/ip/$ip";
+ warn "$mac IP changed to $ip";
+ }
+
+ print "$mac NEW $ip\n";
+
return $ip;
}
+my $transaction = 0; # FIXME predictible transaction numbers
+
while (1) {
+ require "config.pl"; # refresh config
+
print "waiting for DHCP requests on ",$sock->sockhost,":",$sock->sockport,"\n";
my $buf;
$sock->recv($buf, 1024);
- print "<< peer:",$sock->peerhost,":",$sock->peerport,"\n";
+ print "<< ",$sock->peerhost,":",$sock->peerport,"\n";
if (defined $buf) {
- my $dhcp;
-
- eval { $dhcp = Net::DHCP::Packet->new($buf); };
- die "can't use request", dump( $buf ) if $@;
+ my $dhcp = Net::DHCP::Packet->new($buf);
+ $dhcp->comment( $transaction++ );
- if ( $debug ) {
- warn "recv: ", $dhcp->toString, "\n\n";
- }
+ warn "recv: ", $dhcp->toString, "\n\n";
my $mac = substr($dhcp->chaddr(),0,$dhcp->hlen()*2);
my $ip = client_ip($mac);
+ my $user_class = $dhcp->getOptionValue(DHO_USER_CLASS());
- my $file = $next_file;
- $file = 'undionly.kpxe' if ! $file || $dhcp->getOptionValue(DHO_USER_CLASS()) ne 'gPXE';
+ if ( $user_class eq 'gPXE' ) {
+ $file = $gpxe_file;
+ } elsif ( ! $file ) {
+ $file = 'undionly.kpxe';
+ }
- my $packet = new Net::DHCP::Packet(
+ my $packet = {
Op => BOOTREPLY(),
Hops => $dhcp->hops(),
Xid => $dhcp->xid(),
Chaddr => $dhcp->chaddr(),
File => $file,
# DHO_DHCP_MESSAGE_TYPE() => DHCPACK(),
- DHO_SUBNET_MASK() => '255.0.0.0',
- );
+# DHO_SUBNET_MASK() => '255.255.255.0',
+ };
+
+ my $messagetype = $dhcp->getOptionValue(DHO_DHCP_MESSAGE_TYPE());
+
+ if ($messagetype eq DHCPDISCOVER()) {
+ warn "DHCP DISCOVER";
+ $packet->{Comment} = $dhcp->comment();
+ $packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPOFFER();
+ } elsif ($messagetype eq DHCPREQUEST()) {
+ my $requested_ip = $dhcp->getOptionValue(DHO_DHCP_REQUESTED_ADDRESS());
+ warn "DHCP REQUEST $requested_ip";
+ if ( $ip eq $requested_ip ) {
+ $packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPACK();
+ $packet->{DHO_DHCP_LEASE_TIME()} = 100;
+ } else {
+ $packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPNAK();
+ $packet->{DHO_DHCP_MESSAGE()} = "Bad request, expected $ip";
+ }
+ } elsif ($messagetype eq DHCPINFORM()) {
+ warn "DHCP INFORM ignored";
+ } else {
+ warn "$messagetype igored (bootp?)";
+ }
+
+
+ warn ">> $mac == $ip server: $server_ip", $file ? " file: $file\n" : "\n";
- warn ">> $mac == $ip server $server_ip\n";
-
+ $packet = new Net::DHCP::Packet( %$packet );
warn "## ",$packet->toString(),"\n" if $debug;
my $reply = IO::Socket::INET->new(