1 |
dpavlin |
1 |
#!/usr/bin/perl |
2 |
|
|
|
3 |
|
|
# based on http://www.perlmonks.org/index.pl?node_id=325248 |
4 |
|
|
|
5 |
|
|
use strict; |
6 |
|
|
use warnings; |
7 |
|
|
|
8 |
dpavlin |
22 |
use autodie; |
9 |
|
|
|
10 |
dpavlin |
1 |
use IO::Socket::INET; |
11 |
dpavlin |
17 |
use File::Slurp; |
12 |
dpavlin |
1 |
use Data::Dump qw/dump/; |
13 |
dpavlin |
36 |
use Net::Ping; |
14 |
dpavlin |
1 |
|
15 |
dpavlin |
27 |
use lib 'lib'; |
16 |
|
|
use Net::DHCP::Packet; |
17 |
|
|
use Net::DHCP::Constants 0.67; |
18 |
dpavlin |
1 |
die "need to run $0 as root like this\nsudo $0\n" unless $< == 0; |
19 |
|
|
|
20 |
|
|
my $debug = shift @ARGV; |
21 |
|
|
|
22 |
dpavlin |
22 |
our ( $file, $gpxe_file ); |
23 |
dpavlin |
17 |
our ( $ip_from, $ip_to ) = ( 10, 100 ); |
24 |
dpavlin |
1 |
|
25 |
dpavlin |
22 |
our $server_ip = readlink 'conf/server.ip' if -l 'conf/server.ip'; |
26 |
dpavlin |
17 |
|
27 |
dpavlin |
22 |
if ( ! $server_ip ) { |
28 |
|
|
$server_ip = `/sbin/ifconfig`; |
29 |
|
|
$server_ip =~ s/^.+?addr:([\d\.]+).*$/$1/gs; |
30 |
|
|
warn "auto-configure server ip to $server_ip\n"; |
31 |
|
|
} else { |
32 |
|
|
warn "server ip $server_ip\n"; |
33 |
|
|
} |
34 |
|
|
|
35 |
dpavlin |
1 |
my $sock = IO::Socket::INET->new( |
36 |
|
|
LocalPort => 67, |
37 |
|
|
# LocalAddr => 'localhost', |
38 |
|
|
# LocalAddr => '10.0.0.100', |
39 |
|
|
LocalAddr => '0.0.0.0', |
40 |
|
|
Proto => 'udp', |
41 |
|
|
ReuseAddr => 1, |
42 |
|
|
# PeerPort => getservbyname('bootpc', 'udp'), |
43 |
|
|
Broadcast => 1, |
44 |
|
|
Type => SOCK_DGRAM, |
45 |
|
|
) or die "Failed to bind to socket: $@"; |
46 |
|
|
|
47 |
|
|
|
48 |
dpavlin |
17 |
my $addr = $ip_from; |
49 |
|
|
|
50 |
dpavlin |
1 |
sub client_ip { |
51 |
|
|
my ( $mac ) = @_; |
52 |
|
|
|
53 |
dpavlin |
17 |
my $conf = "conf/$server_ip"; |
54 |
|
|
mkdir $conf unless -e $conf; |
55 |
dpavlin |
1 |
|
56 |
dpavlin |
22 |
if ( -e "$conf/mac/$mac" ) { |
57 |
|
|
my $ip = read_file "$conf/mac/$mac"; |
58 |
dpavlin |
17 |
print "$mac old $ip\n"; |
59 |
|
|
return $ip; |
60 |
|
|
} |
61 |
dpavlin |
1 |
|
62 |
dpavlin |
17 |
mkdir $_ foreach grep { ! -e $_ } map { "$conf/$_" } ( 'ip', 'mac' ); |
63 |
|
|
|
64 |
dpavlin |
36 |
my $p = Net::Ping->new; |
65 |
|
|
|
66 |
dpavlin |
17 |
my $prefix = $server_ip; |
67 |
|
|
$prefix =~ s{\.\d+$}{.}; |
68 |
|
|
my $ip = $prefix . $addr; |
69 |
dpavlin |
36 |
while ( -e "conf/ip/$ip" || $p->ping( $ip ) ) { |
70 |
dpavlin |
17 |
$ip = $prefix . $addr++; |
71 |
|
|
die "all addresses allocated!" if $addr == $ip_to; |
72 |
dpavlin |
1 |
} |
73 |
|
|
|
74 |
dpavlin |
17 |
write_file "$conf/mac/$mac", $ip; |
75 |
dpavlin |
33 |
if ( -l "$conf/ip/$ip" && readlink "$conf/ip/$ip" ne "$conf/mac/$mac") { |
76 |
|
|
unlink "$conf/ip/$ip"; |
77 |
|
|
symlink "$conf/mac/$mac", "$conf/ip/$ip"; |
78 |
|
|
warn "$mac IP changed to $ip"; |
79 |
|
|
} |
80 |
dpavlin |
17 |
|
81 |
|
|
print "$mac NEW $ip\n"; |
82 |
|
|
|
83 |
dpavlin |
1 |
return $ip; |
84 |
|
|
} |
85 |
|
|
|
86 |
dpavlin |
27 |
my $transaction = 0; # FIXME predictible transaction numbers |
87 |
|
|
|
88 |
dpavlin |
1 |
while (1) { |
89 |
|
|
|
90 |
dpavlin |
12 |
require "config.pl"; # refresh config |
91 |
|
|
|
92 |
dpavlin |
1 |
print "waiting for DHCP requests on ",$sock->sockhost,":",$sock->sockport,"\n"; |
93 |
|
|
|
94 |
|
|
my $buf; |
95 |
|
|
$sock->recv($buf, 1024); |
96 |
dpavlin |
17 |
print "<< ",$sock->peerhost,":",$sock->peerport,"\n"; |
97 |
dpavlin |
1 |
|
98 |
|
|
if (defined $buf) { |
99 |
|
|
|
100 |
dpavlin |
27 |
my $dhcp = Net::DHCP::Packet->new($buf); |
101 |
|
|
$dhcp->comment( $transaction++ ); |
102 |
dpavlin |
1 |
|
103 |
dpavlin |
27 |
warn "recv: ", $dhcp->toString, "\n\n"; |
104 |
dpavlin |
1 |
|
105 |
|
|
my $mac = substr($dhcp->chaddr(),0,$dhcp->hlen()*2); |
106 |
|
|
my $ip = client_ip($mac); |
107 |
dpavlin |
22 |
my $user_class = $dhcp->getOptionValue(DHO_USER_CLASS()); |
108 |
dpavlin |
1 |
|
109 |
dpavlin |
22 |
if ( $user_class eq 'gPXE' ) { |
110 |
|
|
$file = $gpxe_file; |
111 |
|
|
} elsif ( ! $file ) { |
112 |
|
|
$file = 'undionly.kpxe'; |
113 |
dpavlin |
12 |
} |
114 |
dpavlin |
6 |
|
115 |
dpavlin |
27 |
my $packet = { |
116 |
dpavlin |
1 |
Op => BOOTREPLY(), |
117 |
|
|
Hops => $dhcp->hops(), |
118 |
|
|
Xid => $dhcp->xid(), |
119 |
|
|
Flags => $dhcp->flags(), |
120 |
|
|
Ciaddr => $dhcp->ciaddr(), |
121 |
|
|
Yiaddr => $ip, |
122 |
dpavlin |
3 |
Siaddr => $server_ip, |
123 |
dpavlin |
1 |
Giaddr => $dhcp->giaddr(), |
124 |
|
|
Chaddr => $dhcp->chaddr(), |
125 |
dpavlin |
6 |
File => $file, |
126 |
dpavlin |
27 |
}; |
127 |
dpavlin |
1 |
|
128 |
dpavlin |
27 |
my $messagetype = $dhcp->getOptionValue(DHO_DHCP_MESSAGE_TYPE()); |
129 |
dpavlin |
22 |
|
130 |
dpavlin |
27 |
if ($messagetype eq DHCPDISCOVER()) { |
131 |
|
|
warn "DHCP DISCOVER"; |
132 |
|
|
$packet->{Comment} = $dhcp->comment(); |
133 |
|
|
$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPOFFER(); |
134 |
|
|
} elsif ($messagetype eq DHCPREQUEST()) { |
135 |
|
|
my $requested_ip = $dhcp->getOptionValue(DHO_DHCP_REQUESTED_ADDRESS()); |
136 |
|
|
warn "DHCP REQUEST $requested_ip"; |
137 |
|
|
if ( $ip eq $requested_ip ) { |
138 |
dpavlin |
40 |
$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPACK(); |
139 |
|
|
$packet->{DHO_DHCP_LEASE_TIME()} = 5 * 60; # 5 min |
140 |
|
|
# $packet->{DHO_DHCP_SERVER_IDENTIFIER()} = $server_ip; # FIXME |
141 |
|
|
$packet->{DHO_SUBNET_MASK()} = '255.255.255.0'; |
142 |
|
|
$packet->{DHO_ROUTERS()} = $server_ip; |
143 |
|
|
# $packet->{DHO_DOMAIN_NAME()} = 'pxelator.lan'; |
144 |
|
|
# $packet->{DHO_NAME_SERVERS()} = $server_ip; |
145 |
|
|
# $packet->{DHO_ROOT_PATH()} = '/exports/foobar'; |
146 |
dpavlin |
27 |
} else { |
147 |
|
|
$packet->{DHO_DHCP_MESSAGE_TYPE()} = DHCPNAK(); |
148 |
|
|
$packet->{DHO_DHCP_MESSAGE()} = "Bad request, expected $ip"; |
149 |
|
|
} |
150 |
|
|
} elsif ($messagetype eq DHCPINFORM()) { |
151 |
|
|
warn "DHCP INFORM ignored"; |
152 |
|
|
} else { |
153 |
|
|
warn "$messagetype igored (bootp?)"; |
154 |
|
|
} |
155 |
|
|
|
156 |
|
|
|
157 |
|
|
warn ">> $mac == $ip server: $server_ip", $file ? " file: $file\n" : "\n"; |
158 |
|
|
|
159 |
|
|
$packet = new Net::DHCP::Packet( %$packet ); |
160 |
dpavlin |
1 |
warn "## ",$packet->toString(),"\n" if $debug; |
161 |
|
|
|
162 |
|
|
my $reply = IO::Socket::INET->new( |
163 |
dpavlin |
3 |
LocalAddr => $server_ip, |
164 |
dpavlin |
1 |
LocalPort => 67, |
165 |
|
|
Proto => "udp", |
166 |
|
|
Broadcast => 1, |
167 |
|
|
PeerAddr => '255.255.255.255', |
168 |
|
|
PeerPort => 68, |
169 |
|
|
Reuse => 1, |
170 |
|
|
) or die "socket: $@"; |
171 |
|
|
|
172 |
|
|
my $buff = $packet->serialize(); |
173 |
|
|
$reply->send( $buff, 0 ) or die "Error sending: $!\n"; |
174 |
|
|
|
175 |
|
|
# system("arp -s $ip $mac"), |
176 |
|
|
|
177 |
|
|
} else { |
178 |
|
|
print "No bootp request.\n"; |
179 |
|
|
} |
180 |
|
|
|
181 |
|
|
} |