1#! /usr/bin/perl -w
2
3# Copyright (c) 2007,2009 by Internet Systems Consortium, Inc. ("ISC")
4#
5# Permission to use, copy, modify, and distribute this software for any
6# purpose with or without fee is hereby granted, provided that the above
7# copyright notice and this permission notice appear in all copies.
8#
9# THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11# MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16#
17#   Internet Systems Consortium, Inc.
18#   950 Charter Street
19#   Redwood City, CA 94063
20#   <info@isc.org>
21#   https://www.isc.org/
22
23use strict;
24use English;
25use Time::HiRes qw( sleep );
26use Socket;
27use Socket6;
28use IO::Select;
29
30use dhcp_client;
31
32# XXX: for debugging
33use Data::Dumper;
34
35# not-yet-standard options
36my $OPT_TIME_SERVERS = 40;
37my $OPT_TIME_OFFSET = 41;
38
39# DOCSIS sub-options
40my $DOCSIS_OPT_ORO = 1;
41# 2 to 31 are reserved
42my $DOCSIS_OPT_TFTP_SERVERS = 32;
43my $DOCSIS_OPT_CONFIG_FILE_NAME = 33;
44my $DOCSIS_OPT_SYSLOG_SERVERS = 34;
45my $DOCSIS_OPT_TLV5 = 35;
46my $DOCSIS_OPT_DEVICE_ID = 36;
47my $DOCSIS_OPT_CCC = 37;
48my $DOCSIS_OPT_VERS = 38;
49
50# well-known addresses
51my $All_DHCP_Relay_Agents_and_Servers = "ff02::1:2";
52my $All_DHCP_Servers = "ff05::1:3";
53
54# ports
55my $client_port = 546;
56my $server_port = 547;
57
58# create a new Solicit message
59my $msg = dhcp_client::msg->new($MSG_SOLICIT);
60
61# add the Client Identifier (required by DOCSIS and RFC 3315)
62$msg->add_option($OPT_CLIENTID, dhcp_client::duid());
63
64# add Elapsed Time, set to 0 on first packet (required by RFC 3315)
65$msg->add_option($OPT_ELAPSED_TIME, "\x00\x00");
66
67# add IA_NA for each interface (required by DOCSIS and RFC 3315)
68# XXX: should this be a single interface only?
69my $iaid = 0;
70foreach my $iface (dhcp_client::iface()) {
71	my $option_data = pack("NNN", ++$iaid, 0, 0);
72	$msg->add_option($OPT_IA_NA, $option_data);
73}
74
75# add Reconfigure Accept (required by DOCSIS)
76$msg->add_option($OPT_RECONF_ACCEPT, "");
77
78# add Options Request (required by DOCSIS, recommended by RFC 3315)
79my @oro = ( $OPT_TIME_SERVERS, $OPT_TIME_OFFSET );
80$msg->add_option($OPT_ORO, pack("n*", @oro));
81
82
83# add Vendor Class option (required by DOCSIS)
84$msg->add_option($OPT_VENDOR_CLASS, pack("N", 4491) . "docsis3.0");
85
86# add Vendor-specific Information Option option (required by DOCSIS)
87my $vsio = pack("N", 4491);
88
89# ORO (required by DOCSIS)
90my @docsis_oro = ( $DOCSIS_OPT_TFTP_SERVERS );
91$vsio .= pack("nnC*", $DOCSIS_OPT_ORO, 0+@docsis_oro, @docsis_oro);
92
93# TLV5 data: CMTS DOCSIS version number 3.0 (required by DOCSIS)
94my $tlv5_data = "\x01\x02\x03\x0";
95$vsio .= pack("nn", $DOCSIS_OPT_TLV5, length($tlv5_data)) . $tlv5_data;
96
97# DOCSIS Device (required by DOCSIS)
98my $docsis_device_id = dhcp_client::mac_addr_binary();
99$vsio .= pack("nn", $DOCSIS_OPT_DEVICE_ID, length($docsis_device_id));
100$vsio .= $docsis_device_id;
101
102$msg->add_option($OPT_VENDOR_OPTS, $vsio);
103
104# add Rapid Commit option (required by DOCSIS)
105$msg->add_option($OPT_RAPID_COMMIT, "");
106
107# timeout parameters, from DOCSIS
108my $IRT = $SOL_TIMEOUT;
109my $MRT = $SOL_MAX_RT;
110my $MRC = 4;	# DOCSIS says 4, RFC 3315 says it SHOULD be 0
111my $MRD = 0;
112
113# sleep a random amount of time between 0 and 1 second, required by RFC 3315
114# XXX: this seems pretty stupid
115sleep(rand($SOL_MAX_DELAY));
116
117my $RT;
118my $count = 0;
119my $mrd_end_time;
120if ($MRD != 0) {
121	$mrd_end_time = time() + $MRD;
122}
123my $reply_msg;
124do {
125	# create our socket, and send our Solicit
126	socket(SOCK, PF_INET6, SOCK_DGRAM, getprotobyname('udp')) || die;
127	my $addr = inet_pton(AF_INET6, $All_DHCP_Servers);
128	my $packet = $msg->packet();
129	my $send_ret = send(SOCK, $packet, 0,
130			    pack_sockaddr_in6($server_port, $addr));
131	if (not defined($send_ret)) {
132		printf STDERR
133			"Error \%d sending DHCPv6 Solicit message;\n\%s\n",
134			0+$ERRNO, $ERRNO;
135		exit(1);
136	} elsif ($send_ret != length($packet)) {
137		print STDERR "Unable to send entire DHCPv6 Solicit message.\n";
138		exit(1);
139	}
140	$count++;
141
142	my $RAND = rand(0.2) - 0.1;
143	if (defined $RT) {
144		$RT = 2*$RT + $RAND*$RT;
145		if (($RT > $MRT) && ($MRT != 0)) {
146			$RT = $MRT + $RAND*$RT;
147		}
148	} else {
149		$RT = $IRT + $RAND*$IRT;
150	}
151
152	my $rt_end_time = time() + $RT;
153	if (defined($mrd_end_time) && ($mrd_end_time > $rt_end_time)) {
154		$rt_end_time = $mrd_end_time;
155	}
156
157	for (;;) {
158		my $timeout = $rt_end_time - time();
159		if ($timeout < 0) {
160#			print STDERR "Timeout waiting for DHCPv6 Advertise ",
161#				"or Reply message.\n";
162			last;
163		}
164
165		my @ready = IO::Select->new(\*SOCK)->can_read($timeout);
166
167		if (@ready) {
168			my $reply;
169			my $recv_ret;
170
171			$recv_ret = recv(SOCK, $reply, 1500, 0);
172			if (not defined $recv_ret) {
173				printf STDERR
174					"Error \%d receiving DHCPv6 " .
175						"message;\n\%s\n",
176					0+$ERRNO, $ERRNO;
177				exit(1);
178			}
179
180			$reply_msg = dhcp_client::msg::decode($reply, 1);
181			if (($reply_msg->{msg_type} == $MSG_ADVERTISE) ||
182			    ($reply_msg->{msg_type} == $MSG_REPLY)) {
183			    	last;
184			}
185		}
186	}
187
188} until ($reply_msg ||
189	 (($MRC != 0) && ($count > $MRC)) ||
190	 (defined($mrd_end_time) && ($mrd_end_time > time())));
191
192unless ($reply_msg) {
193	if (($MRC != 0) && ($count >= $MRC)) {
194		print STDERR
195			"No reply after maximum retransmission count.\n";
196	} else {
197		print STDERR
198			"No reply after maximum retransmission duration.\n";
199	}
200}
201
202if ($reply_msg && ($reply_msg->{msg_type} == $MSG_REPLY)) {
203	print "Got DHCPv6 Reply message.\n";
204	exit(0);
205}
206
207#$Data::Dumper::Useqq = 1;
208#print Dumper($msg), "\n";
209#print Dumper($msg->packet()), "\n";
210#
211#print "packet length: ", length($msg->packet()), "\n";
212
213