| 1 |
#!/usr/bin/perl |
| 2 |
|
| 3 |
=head1 dhcpd |
| 4 |
|
| 5 |
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 |
use strict; |
| 14 |
use warnings; |
| 15 |
|
| 16 |
use autodie; |
| 17 |
|
| 18 |
use IO::Socket::INET; |
| 19 |
use File::Slurp; |
| 20 |
use Data::Dump qw/dump/; |
| 21 |
use Net::Ping; |
| 22 |
use Module::Refresh; |
| 23 |
|
| 24 |
use lib '..'; |
| 25 |
use Net::DHCP::Packet; |
| 26 |
use Net::DHCP::Constants 0.67; |
| 27 |
|
| 28 |
use server; |
| 29 |
|
| 30 |
my $debug = 1; |
| 31 |
|
| 32 |
our ( $file, $gpxe_file ); |
| 33 |
our ( $ip_from, $ip_to ) = ( 10, 100 ); |
| 34 |
|
| 35 |
if ( ! $server::ip ) { |
| 36 |
my $server_ip = `/sbin/ifconfig`; |
| 37 |
$server_ip =~ s/^.+?addr:([\d\.]+).*$/$1/gs; |
| 38 |
$server::ip = $server_ip; |
| 39 |
} |
| 40 |
|
| 41 |
warn "server ip $server::ip\n"; |
| 42 |
|
| 43 |
my $addr = $ip_from; |
| 44 |
|
| 45 |
sub client_ip { |
| 46 |
my ( $mac ) = @_; |
| 47 |
|
| 48 |
my $conf = "conf/$server::ip"; |
| 49 |
mkdir $conf unless -e $conf; |
| 50 |
|
| 51 |
if ( -e "$conf/mac/$mac" ) { |
| 52 |
my $ip = read_file "$conf/mac/$mac"; |
| 53 |
print "$mac old $ip\n"; |
| 54 |
return $ip; |
| 55 |
} |
| 56 |
|
| 57 |
mkdir $_ foreach grep { ! -e $_ } map { "$conf/$_" } ( 'ip', 'mac' ); |
| 58 |
|
| 59 |
my $p = Net::Ping->new; |
| 60 |
|
| 61 |
my $prefix = $server::ip; |
| 62 |
$prefix =~ s{\.\d+$}{.}; |
| 63 |
my $ip = $prefix . $addr; |
| 64 |
while ( -e "conf/ip/$ip" || $p->ping( $ip ) ) { |
| 65 |
$ip = $prefix . $addr++; |
| 66 |
die "all addresses allocated!" if $addr == $ip_to; |
| 67 |
} |
| 68 |
|
| 69 |
write_file "$conf/mac/$mac", $ip; |
| 70 |
if ( -l "$conf/ip/$ip" && readlink "$conf/ip/$ip" ne "$conf/mac/$mac") { |
| 71 |
unlink "$conf/ip/$ip"; |
| 72 |
symlink "$conf/mac/$mac", "$conf/ip/$ip"; |
| 73 |
warn "$mac IP changed to $ip"; |
| 74 |
} |
| 75 |
|
| 76 |
print "$mac NEW $ip\n"; |
| 77 |
|
| 78 |
return $ip; |
| 79 |
} |
| 80 |
|
| 81 |
our $transaction = 0; # FIXME predictible transaction numbers |
| 82 |
|
| 83 |
sub process_packet { |
| 84 |
my $sock = shift; |
| 85 |
|
| 86 |
my $buf; |
| 87 |
$sock->recv($buf, 1024); |
| 88 |
my $size = 'empty'; |
| 89 |
$size = length($buf) . ' bytes' if defined $buf; |
| 90 |
|
| 91 |
print "packet from ",$sock->peerhost,":",$sock->peerport," $size\n"; |
| 92 |
return unless $buf; |
| 93 |
|
| 94 |
my $dhcp = Net::DHCP::Packet->new($buf); |
| 95 |
$dhcp->comment( $transaction++ ); |
| 96 |
|
| 97 |
warn "recv: ", $dhcp->toString; |
| 98 |
|
| 99 |
my $mac = substr($dhcp->chaddr(),0,$dhcp->hlen()*2); |
| 100 |
my $ip = client_ip($mac); |
| 101 |
|
| 102 |
=for later |
| 103 |
|
| 104 |
my $user_class = $dhcp->getOptionValue(DHO_USER_CLASS()); |
| 105 |
|
| 106 |
if ( $user_class eq 'gPXE' ) { |
| 107 |
$file = $gpxe_file; |
| 108 |
} elsif ( ! $file ) { |
| 109 |
$file = 'undionly.kpxe'; |
| 110 |
} |
| 111 |
|
| 112 |
=cut |
| 113 |
|
| 114 |
my $packet = { |
| 115 |
Op => BOOTREPLY(), |
| 116 |
Hops => $dhcp->hops(), |
| 117 |
Xid => $dhcp->xid(), |
| 118 |
Flags => $dhcp->flags(), |
| 119 |
Ciaddr => $dhcp->ciaddr(), |
| 120 |
Yiaddr => $ip, |
| 121 |
Siaddr => $server::ip, |
| 122 |
Giaddr => $dhcp->giaddr(), |
| 123 |
Chaddr => $dhcp->chaddr(), |
| 124 |
File => $file, |
| 125 |
}; |
| 126 |
|
| 127 |
my $messagetype = $dhcp->getOptionValue(DHO_DHCP_MESSAGE_TYPE()); |
| 128 |
|
| 129 |
if ($messagetype eq DHCPDISCOVER()) { |
| 130 |
warn "DHCP DISCOVER"; |
| 131 |
$packet->{Comment} = $dhcp->comment(); |
| 132 |
$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPOFFER(); |
| 133 |
} elsif ($messagetype eq DHCPREQUEST()) { |
| 134 |
my $requested_ip = $dhcp->getOptionValue(DHO_DHCP_REQUESTED_ADDRESS()); |
| 135 |
warn "DHCP REQUEST $requested_ip"; |
| 136 |
if ( $ip eq $requested_ip ) { |
| 137 |
$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPACK(); |
| 138 |
$packet->{DHO_DHCP_LEASE_TIME()} = 5 * 60; # 5 min |
| 139 |
# $packet->{DHO_DHCP_SERVER_IDENTIFIER()} = $server::ip; # FIXME |
| 140 |
$packet->{DHO_SUBNET_MASK()} = '255.255.255.0'; |
| 141 |
$packet->{DHO_ROUTERS()} = $server::ip; |
| 142 |
# $packet->{DHO_DOMAIN_NAME()} = 'pxelator.lan'; |
| 143 |
# $packet->{DHO_NAME_SERVERS()} = $server::ip; |
| 144 |
# $packet->{DHO_ROOT_PATH()} = '/exports/foobar'; |
| 145 |
} else { |
| 146 |
$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPNAK(); |
| 147 |
$packet->{DHO_DHCP_MESSAGE()} = "Bad request, expected $ip"; |
| 148 |
} |
| 149 |
} elsif ($messagetype eq DHCPINFORM()) { |
| 150 |
warn "DHCP INFORM ignored"; |
| 151 |
} else { |
| 152 |
warn "$messagetype igored (bootp?)"; |
| 153 |
} |
| 154 |
|
| 155 |
warn ">> $mac == $ip server: $server::ip", $file ? " file: $file\n" : "\n"; |
| 156 |
|
| 157 |
$packet = new Net::DHCP::Packet( %$packet ); |
| 158 |
warn "## ",$packet->toString(),"\n" if $debug; |
| 159 |
|
| 160 |
my $reply = IO::Socket::INET->new( |
| 161 |
LocalAddr => $server::ip, |
| 162 |
LocalPort => 67, |
| 163 |
Proto => "udp", |
| 164 |
Broadcast => 1, |
| 165 |
PeerAddr => '255.255.255.255', |
| 166 |
PeerPort => 68, |
| 167 |
Reuse => 1, |
| 168 |
) or die "socket: $@"; |
| 169 |
|
| 170 |
my $buff = $packet->serialize(); |
| 171 |
$reply->send( $buff, 0 ) or die "Error sending: $!\n"; |
| 172 |
|
| 173 |
# system("arp -s $ip $mac"), |
| 174 |
|
| 175 |
} |
| 176 |
|
| 177 |
sub start { |
| 178 |
|
| 179 |
my $sock = IO::Socket::INET->new( |
| 180 |
LocalPort => 67, |
| 181 |
# LocalAddr => 'localhost', |
| 182 |
# LocalAddr => '10.0.0.100', |
| 183 |
LocalAddr => '0.0.0.0', |
| 184 |
Proto => 'udp', |
| 185 |
ReuseAddr => 1, |
| 186 |
# PeerPort => getservbyname('bootpc', 'udp'), |
| 187 |
Broadcast => 1, |
| 188 |
Type => SOCK_DGRAM, |
| 189 |
) or die "Failed to bind to socket: $@"; |
| 190 |
|
| 191 |
print "DHCP listen on ",$sock->sockhost,":",$sock->sockport,"\n"; |
| 192 |
|
| 193 |
while (1) { |
| 194 |
Module::Refresh->refresh; |
| 195 |
process_packet $sock; |
| 196 |
} |
| 197 |
} |
| 198 |
|
| 199 |
1; |
Parent Directory
| 
Revision Log