lib/PXElator/dhcpd.pm

package dhcpd;

=head1 dhcpd

start with:

 perl -Ilib/PXElator -Ilib -Mdhcpd -e start

based on L<http://www.perlmonks.org/index.pl?node_id=325248>

=cut

use strict;
use warnings;

use autodie;

use IO::Socket::INET;
use File::Slurp;
use Data::Dump qw/dump/;

use lib '..';
use Net::DHCP::Packet;
use Net::DHCP::Constants 0.67;

use CouchDB;
use format;

use server;
my $debug = server::debug;

if ( ! $server::ip ) {
        my $server_ip = `/sbin/ifconfig`;
        $server_ip =~ s/^.+?addr:([\d\.]+).*$/$1/gs;
        $server::ip = $server_ip;
}

warn "server ip $server::ip range: $server::ip_from - $server::ip_to\n";

use client;

sub client_mac_ip {
        my ( $mac, $request_ip ) = @_;

        if ( ! $mac ) {
                warn "W: no mac in requiest\n";
                return;
        }

        my $conf = $server::conf;
        mkdir $conf unless -e $conf;

        my $ip;

        if ( $ip = client::ip_from_mac( $mac ) ) {
                print "RENEW $mac $ip\n";
                client::save_ip_mac( $ip, $mac );
                return $ip;
        } elsif ( ip::in_dhcp_range( $request_ip ) || $request_ip eq '0.0.0.0' ) {
                $ip = client::next_ip( $mac );
                print "NEW $mac $ip\n";
        } else {
                $ip = $request_ip;
                client::save_ip_mac( $ip, $mac );
                warn "W: $ip our of server range $server::ip $server::netmask\n";
        }

        return $ip;
}

use log;
use config;
use pxelinux;
use client;

our $file;
our $transaction = 0; # FIXME predictible transaction numbers

sub process_packet {
        my $sock = shift;

        server->refresh;

        my $buf;
        $sock->recv($buf, 1024);
        my $size = 'empty';
        $size = length($buf) . ' bytes' if defined $buf;

        print "packet from ",$sock->peerhost,":",$sock->peerport," $size\n" if $debug;
        return unless $buf;

        my $dhcp = Net::DHCP::Packet->new($buf);

        warn "recv: ", $dhcp->toString if $debug;

        $dhcp->comment( $transaction++ );

        my $mac = format::mac( substr($dhcp->chaddr(),0,$dhcp->hlen()*2) );
        my $ip = client_mac_ip($mac, $dhcp->ciaddr);

        my $hostname = $dhcp->getOptionValue(DHO_HOST_NAME);
        print "$ip ", client::conf( $ip => 'hostname', default => $hostname ), " >> /etc/hosts\n" if $hostname;

        my $audit = { mac => $mac, ip => $ip, hostname => $hostname,
                options => {
                        map {
                                ( $_ => $dhcp->getOptionValue( $_ ) )
                        } @{ $dhcp->{options_order} }
                },
        };

=for later

        my $user_class = $dhcp->getOptionValue(DHO_USER_CLASS());

        if ( $user_class eq 'gPXE' ) {
                $file = $gpxe_file;
        } elsif ( ! $file ) {
                $file = 'undionly.kpxe';
        }

=cut

        config::for_ip( $ip );

        my $packet = {
                Op              => BOOTREPLY(),
                Hops    => $dhcp->hops(),
                Xid             => $dhcp->xid(),
                Flags   => $dhcp->flags(),
                Ciaddr  => $dhcp->ciaddr(),
                Yiaddr  => $ip,
                Siaddr  => $server::ip,
                Giaddr  => $dhcp->giaddr(),
                Chaddr  => $dhcp->chaddr(),
                File    => $file,
                DHO_DHCP_SERVER_IDENTIFIER()    => $server::ip, # busybox/udhcpc needs it but doesn't request
        };

        my $options = {
                DHO_SUBNET_MASK()       => $server::netmask,
                DHO_ROUTERS()           => $server::ip,
                DHO_DOMAIN_NAME()       => $server::domain,
                DHO_NAME_SERVERS()      => $server::ip,
                DHO_DOMAIN_NAME_SERVERS() => $server::ip,
                DHO_HOST_NAME()         => client::conf( $ip, 'hostname' ),
                DHO_BROADCAST_ADDRESS() => $server::bcast,
#               DHO_NTP_SERVERS() => '',
        };

        my @requested = split(/\s/, $dhcp->getOptionValue(DHO_DHCP_PARAMETER_REQUEST_LIST));
        warn "options ",dump( $options ), ' requested: ',dump( @requested ) if $debug;

        my @missing;
        foreach ( @requested ) {
                if ( defined $options->{$_} ) {
                        $packet->{$_} = $options->{$_};
                } else {
                        push @missing, $_;
                }
        }

        warn "W: options requested but missing: ",dump( @missing ),$/;
        $audit->{requested} = [ @requested ];
        $audit->{missing}   = [ @missing   ];

        foreach my $opt ( 'magic', 'config_file', 'path_prefix', 'reboot_time' ) {
                my $DH0 = eval 'DHO_PXELINUX_' . uc $opt;
                warn "DH0: $@" if $@;
                my $v = eval "\$pxelinux::$opt";
                warn "v: $@" if $@;
                next unless defined $v;
                warn "pxelinux dhcp option $opt = $DH0 = $v\n" if $debug;
                $packet->{ $DH0 } = $v;
        }

        my $messagetype = $dhcp->getOptionValue(DHO_DHCP_MESSAGE_TYPE());

        if ($messagetype eq DHCPDISCOVER()) {
                $audit->{type} = 'discover';
                $packet->{Comment} = $dhcp->comment();
                $packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPOFFER();
        } elsif ($messagetype eq DHCPREQUEST()) {
                my $requested_ip = $dhcp->getOptionValue(DHO_DHCP_REQUESTED_ADDRESS());
                $audit->{type} = 'request';
                if ( $ip eq $requested_ip ) {
                        $packet->{DHO_DHCP_MESSAGE_TYPE()}      = DHCPACK();
                        $packet->{DHO_DHCP_LEASE_TIME()}        = 5 * 60; # 5 min
#                       $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()) {
                $audit->{type} = 'inform';
        } else {
                $audit->{type} = sprintf('ignored %x', $messagetype);
        }

        warn ">> $mac == $ip server: $server::ip", $file ? " file: $file\n" : "\n" if $debug;
        $audit->{response} = $packet;

        $packet = new Net::DHCP::Packet( %$packet );
        warn "send ",$packet->toString() if $debug;

        if ( ip::in_dhcp_range( $ip ) ) {
                my $buff = $packet->serialize();

                my $reply = IO::Socket::INET->new(
                        LocalAddr => $server::ip,
                        LocalPort => 67,
                        Proto => "udp",
                        Broadcast => 1,
                        PeerAddr => '255.255.255.255',
                        PeerPort => 68,
                        Reuse => 1,
                ) or die "socket: $@";

                $reply->send( $buff, 0 ) or die "Error sending: $!\n";
        } else {
                $audit->{error} = "$ip our of our range $server::ip $server::netmask";
                warn $audit->{error};
        }

        CouchDB::audit( $audit->{type}, $audit );

#       system("arp -s $ip $mac"),

}

sub start {

        my $sock = IO::Socket::INET->new(
                LocalPort       => 67,
#               LocalAddr       => 'localhost',
#               LocalAddr       => '10.0.0.100',
                LocalAddr       => '0.0.0.0',
                Proto           => 'udp',
                ReuseAddr       => 1,
#               PeerPort        => getservbyname('bootpc', 'udp'),
                Broadcast       => 1,
                Type            => SOCK_DGRAM,
        ) or die "Failed to bind to socket: $@";

        print "DHCP listen on ",$sock->sockhost,":",$sock->sockport,"\n";

        CouchDB::audit( 'start', { addr => $sock->sockhost, port => $sock->sockport } );

        while (1) {
                process_packet $sock;
        }
}

warn "loaded";

1;
1	dpavlin	48	package dhcpd;
2	dpavlin	1
3	dpavlin	44	=head1 dhcpd
4	dpavlin	1
5	dpavlin	44	start with:
6
7			perl -Ilib/PXElator -Ilib -Mdhcpd -e start
8
9			based on L<http://www.perlmonks.org/index.pl?node_id=325248>
10
11			=cut
12
13	dpavlin	1	use strict;
14			use warnings;
15
16	dpavlin	22	use autodie;
17
18	dpavlin	1	use IO::Socket::INET;
19	dpavlin	17	use File::Slurp;
20	dpavlin	1	use Data::Dump qw/dump/;
21
22	dpavlin	44	use lib '..';
23	dpavlin	27	use Net::DHCP::Packet;
24			use Net::DHCP::Constants 0.67;
25	dpavlin	1
26	dpavlin	207	use CouchDB;
27	dpavlin	208	use format;
28	dpavlin	207
29	dpavlin	44	use server;
30	dpavlin	67	my $debug = server::debug;
31	dpavlin	1
32	dpavlin	44	if ( ! $server::ip ) {
33			my $server_ip = `/sbin/ifconfig`;
34	dpavlin	22	$server_ip =~ s/^.+?addr:([\d\.]+).*$/$1/gs;
35	dpavlin	44	$server::ip = $server_ip;
36	dpavlin	22	}
37
38	dpavlin	110	warn "server ip $server::ip range: $server::ip_from - $server::ip_to\n";
39	dpavlin	1
40	dpavlin	168	use client;
41	dpavlin	17
42	dpavlin	244	sub client_mac_ip {
43			my ( $mac, $request_ip ) = @_;
44	dpavlin	1
45	dpavlin	267	if ( ! $mac ) {
46			warn "W: no mac in requiest\n";
47			return;
48			}
49
50	dpavlin	156	my $conf = $server::conf;
51	dpavlin	17	mkdir $conf unless -e $conf;
52	dpavlin	1
53	dpavlin	177	my $ip;
54
55	dpavlin	194	if ( $ip = client::ip_from_mac( $mac ) ) {
56	dpavlin	94	print "RENEW $mac $ip\n";
57	dpavlin	324	client::save_ip_mac( $ip, $mac );
58	dpavlin	17	return $ip;
59	dpavlin	413	} elsif ( ip::in_dhcp_range( $request_ip ) \|\| $request_ip eq '0.0.0.0' ) {
60	dpavlin	200	$ip = client::next_ip( $mac );
61	dpavlin	177	print "NEW $mac $ip\n";
62	dpavlin	244	} else {
63			$ip = $request_ip;
64			client::save_ip_mac( $ip, $mac );
65			warn "W: $ip our of server range $server::ip $server::netmask\n";
66	dpavlin	17	}
67	dpavlin	1
68			return $ip;
69			}
70
71	dpavlin	110	use log;
72			use config;
73	dpavlin	129	use pxelinux;
74	dpavlin	160	use client;
75	dpavlin	110
76			our $file;
77	dpavlin	44	our $transaction = 0; # FIXME predictible transaction numbers
78	dpavlin	27
79	dpavlin	44	sub process_packet {
80			my $sock = shift;
81	dpavlin	1
82	dpavlin	128	server->refresh;
83
84	dpavlin	1	my $buf;
85			$sock->recv($buf, 1024);
86	dpavlin	44	my $size = 'empty';
87			$size = length($buf) . ' bytes' if defined $buf;
88	dpavlin	1
89	dpavlin	94	print "packet from ",$sock->peerhost,":",$sock->peerport," $size\n" if $debug;
90	dpavlin	44	return unless $buf;
91	dpavlin	1
92	dpavlin	44	my $dhcp = Net::DHCP::Packet->new($buf);
93	dpavlin	1
94	dpavlin	67	warn "recv: ", $dhcp->toString if $debug;
95	dpavlin	1
96	dpavlin	260	$dhcp->comment( $transaction++ );
97
98	dpavlin	313	my $mac = format::mac( substr($dhcp->chaddr(),0,$dhcp->hlen()*2) );
99	dpavlin	244	my $ip = client_mac_ip($mac, $dhcp->ciaddr);
100	dpavlin	1
101	dpavlin	201	my $hostname = $dhcp->getOptionValue(DHO_HOST_NAME);
102	dpavlin	313	print "$ip ", client::conf( $ip => 'hostname', default => $hostname ), " >> /etc/hosts\n" if $hostname;
103	dpavlin	201
104	dpavlin	313	my $audit = { mac => $mac, ip => $ip, hostname => $hostname,
105	dpavlin	260	options => {
106			map {
107			( $_ => $dhcp->getOptionValue( $_ ) )
108			} @{ $dhcp->{options_order} }
109			},
110			};
111	dpavlin	207
112	dpavlin	44	=for later
113	dpavlin	6
114	dpavlin	44	my $user_class = $dhcp->getOptionValue(DHO_USER_CLASS());
115	dpavlin	1
116	dpavlin	44	if ( $user_class eq 'gPXE' ) {
117			$file = $gpxe_file;
118			} elsif ( ! $file ) {
119			$file = 'undionly.kpxe';
120			}
121	dpavlin	22
122	dpavlin	44	=cut
123
124	dpavlin	110	config::for_ip( $ip );
125
126	dpavlin	44	my $packet = {
127			Op => BOOTREPLY(),
128			Hops => $dhcp->hops(),
129			Xid => $dhcp->xid(),
130			Flags => $dhcp->flags(),
131			Ciaddr => $dhcp->ciaddr(),
132			Yiaddr => $ip,
133			Siaddr => $server::ip,
134			Giaddr => $dhcp->giaddr(),
135			Chaddr => $dhcp->chaddr(),
136	dpavlin	110	File => $file,
137	dpavlin	160	DHO_DHCP_SERVER_IDENTIFIER() => $server::ip, # busybox/udhcpc needs it but doesn't request
138	dpavlin	44	};
139
140	dpavlin	160	my $options = {
141			DHO_SUBNET_MASK() => $server::netmask,
142			DHO_ROUTERS() => $server::ip,
143	dpavlin	393	DHO_DOMAIN_NAME() => $server::domain,
144	dpavlin	160	DHO_NAME_SERVERS() => $server::ip,
145			DHO_DOMAIN_NAME_SERVERS() => $server::ip,
146			DHO_HOST_NAME() => client::conf( $ip, 'hostname' ),
147			DHO_BROADCAST_ADDRESS() => $server::bcast,
148			# DHO_NTP_SERVERS() => '',
149			};
150
151			my @requested = split(/\s/, $dhcp->getOptionValue(DHO_DHCP_PARAMETER_REQUEST_LIST));
152	dpavlin	167	warn "options ",dump( $options ), ' requested: ',dump( @requested ) if $debug;
153
154			my @missing;
155	dpavlin	160	foreach ( @requested ) {
156	dpavlin	167	if ( defined $options->{$_} ) {
157			$packet->{$_} = $options->{$_};
158			} else {
159			push @missing, $_;
160			}
161	dpavlin	160	}
162
163	dpavlin	168	warn "W: options requested but missing: ",dump( @missing ),$/;
164	dpavlin	207	$audit->{requested} = [ @requested ];
165			$audit->{missing} = [ @missing ];
166	dpavlin	167
167	dpavlin	129	foreach my $opt ( 'magic', 'config_file', 'path_prefix', 'reboot_time' ) {
168			my $DH0 = eval 'DHO_PXELINUX_' . uc $opt;
169			warn "DH0: $@" if $@;
170			my $v = eval "\$pxelinux::$opt";
171			warn "v: $@" if $@;
172			next unless defined $v;
173	dpavlin	167	warn "pxelinux dhcp option $opt = $DH0 = $v\n" if $debug;
174	dpavlin	129	$packet->{ $DH0 } = $v;
175			}
176
177	dpavlin	44	my $messagetype = $dhcp->getOptionValue(DHO_DHCP_MESSAGE_TYPE());
178
179			if ($messagetype eq DHCPDISCOVER()) {
180	dpavlin	207	$audit->{type} = 'discover';
181	dpavlin	44	$packet->{Comment} = $dhcp->comment();
182			$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPOFFER();
183			} elsif ($messagetype eq DHCPREQUEST()) {
184			my $requested_ip = $dhcp->getOptionValue(DHO_DHCP_REQUESTED_ADDRESS());
185	dpavlin	207	$audit->{type} = 'request';
186	dpavlin	44	if ( $ip eq $requested_ip ) {
187			$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPACK();
188			$packet->{DHO_DHCP_LEASE_TIME()} = 5 * 60; # 5 min
189			# $packet->{DHO_ROOT_PATH()} = '/exports/foobar';
190	dpavlin	27	} else {
191	dpavlin	44	$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPNAK();
192			$packet->{DHO_DHCP_MESSAGE()} = "Bad request, expected $ip";
193	dpavlin	27	}
194	dpavlin	44	} elsif ($messagetype eq DHCPINFORM()) {
195	dpavlin	207	$audit->{type} = 'inform';
196	dpavlin	44	} else {
197	dpavlin	207	$audit->{type} = sprintf('ignored %x', $messagetype);
198	dpavlin	44	}
199	dpavlin	27
200	dpavlin	110	warn ">> $mac == $ip server: $server::ip", $file ? " file: $file\n" : "\n" if $debug;
201	dpavlin	207	$audit->{response} = $packet;
202	dpavlin	27
203	dpavlin	44	$packet = new Net::DHCP::Packet( %$packet );
204	dpavlin	67	warn "send ",$packet->toString() if $debug;
205	dpavlin	27
206	dpavlin	413	if ( ip::in_dhcp_range( $ip ) ) {
207	dpavlin	244	my $buff = $packet->serialize();
208	dpavlin	207
209	dpavlin	244	my $reply = IO::Socket::INET->new(
210			LocalAddr => $server::ip,
211			LocalPort => 67,
212			Proto => "udp",
213			Broadcast => 1,
214			PeerAddr => '255.255.255.255',
215			PeerPort => 68,
216			Reuse => 1,
217			) or die "socket: $@";
218	dpavlin	1
219	dpavlin	244	$reply->send( $buff, 0 ) or die "Error sending: $!\n";
220			} else {
221			$audit->{error} = "$ip our of our range $server::ip $server::netmask";
222	dpavlin	413	warn $audit->{error};
223	dpavlin	244	}
224	dpavlin	1
225	dpavlin	244	CouchDB::audit( $audit->{type}, $audit );
226
227	dpavlin	44	# system("arp -s $ip $mac"),
228	dpavlin	1
229	dpavlin	44	}
230	dpavlin	1
231	dpavlin	44	sub start {
232
233			my $sock = IO::Socket::INET->new(
234			LocalPort => 67,
235			# LocalAddr => 'localhost',
236			# LocalAddr => '10.0.0.100',
237			LocalAddr => '0.0.0.0',
238			Proto => 'udp',
239			ReuseAddr => 1,
240			# PeerPort => getservbyname('bootpc', 'udp'),
241			Broadcast => 1,
242			Type => SOCK_DGRAM,
243			) or die "Failed to bind to socket: $@";
244
245			print "DHCP listen on ",$sock->sockhost,":",$sock->sockport,"\n";
246
247	dpavlin	232	CouchDB::audit( 'start', { addr => $sock->sockhost, port => $sock->sockport } );
248	dpavlin	207
249	dpavlin	44	while (1) {
250			process_packet $sock;
251	dpavlin	1	}
252	dpavlin	44	}
253	dpavlin	1
254	dpavlin	45	warn "loaded";
255
256	dpavlin	44	1;