create log files, reattach existing session

[pxelator] / bin / dhcpd.pl

diff --git a/bin/dhcpd.pl b/bin/dhcpd.pl
index 1b85515..bba1085 100755 (executable)
--- a/bin/dhcpd.pl
+++ b/bin/dhcpd.pl
@@ -5,17 +5,32 @@
 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,
@@ -29,51 +44,75 @@ my $sock = IO::Socket::INET->new(
        Type            => SOCK_DGRAM,
 ) or die "Failed to bind to socket: $@";
 
-my $_ip = 10;
-my $_mac2ip;
-my $_ip_file;
+
+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;
+       }
 
-       $ip = "10.0.0.$_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());
+
+               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(),
@@ -83,15 +122,41 @@ while (1) {
                        Siaddr  => $server_ip,
                        Giaddr  => $dhcp->giaddr(),
                        Chaddr  => $dhcp->chaddr(),
-                       File    => $_ip_file->{$ip} || 'undionly.kpxe',
-#                      DHO_DHCP_MESSAGE_TYPE() => DHCPACK(),
-               DHO_SUBNET_MASK() => '255.0.0.0',
-               );
+                       File    => $file,
+               };
+
+               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()}        = 5 * 60; # 5 min
+#                              $packet->{DHO_DHCP_SERVER_IDENTIFIER()} = $server_ip;           # FIXME
+                               $packet->{DHO_SUBNET_MASK()}            = '255.255.255.0';
+                               $packet->{DHO_ROUTERS()}                = $server_ip;
+#                              $packet->{DHO_DOMAIN_NAME()}            = 'pxelator.lan';
+#                              $packet->{DHO_NAME_SERVERS()}           = $server_ip;
+#                              $packet->{DHO_ROOT_PATH()}              = '/exports/foobar';
+                       } 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?)";
+               }
+
 
-               $_ip_file->{$ip} = $next_file;
+               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(