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_INFORMATION_REQUEST);
60
61# add the Client Identifier (required by DOCSIS and RFC 3315)
62$msg->add_option($OPT_CLIENTID, dhcp_client::duid());
63
64# add the Server Identifier (required by DOCSIS and RFC 3315)
65# but use *our* DUID
66$msg->add_option($OPT_SERVERID, dhcp_client::duid());
67
68# add Elapsed Time, set to 0 on first packet (required by RFC 3315)
69$msg->add_option($OPT_ELAPSED_TIME, "\x00\x00");
70
71# add Reconfigure Accept (required by DOCSIS)
72$msg->add_option($OPT_RECONF_ACCEPT, "");
73
74# add Options Request (required by DOCSIS, recommended by RFC 3315)
75my @oro = ( $OPT_TIME_SERVERS, $OPT_TIME_OFFSET );
76$msg->add_option($OPT_ORO, pack("n*", @oro));
77
78
79# add Vendor Class option (required by DOCSIS)
80$msg->add_option($OPT_VENDOR_CLASS, pack("N", 4491) . "docsis3.0");
81
82# add Vendor-specific Information Option option (required by DOCSIS)
83my $vsio = pack("N", 4491);
84
85# ORO (required by DOCSIS)
86my @docsis_oro = ( $DOCSIS_OPT_TFTP_SERVERS );
87$vsio .= pack("nnC*", $DOCSIS_OPT_ORO, 0+@docsis_oro, @docsis_oro);
88
89# TLV5 data: CMTS DOCSIS version number 3.0 (required by DOCSIS)
90my $tlv5_data = "\x01\x02\x03\x0";
91$vsio .= pack("nn", $DOCSIS_OPT_TLV5, length($tlv5_data)) . $tlv5_data;
92
93# DOCSIS Device (required by DOCSIS)
94my $docsis_device_id = dhcp_client::mac_addr_binary();
95$vsio .= pack("nn", $DOCSIS_OPT_DEVICE_ID, length($docsis_device_id));
96$vsio .= $docsis_device_id;
97
98$msg->add_option($OPT_VENDOR_OPTS, $vsio);
99
100# add Rapid Commit option (required by DOCSIS)
101$msg->add_option($OPT_RAPID_COMMIT, "");
102
103# timeout parameters, from DOCSIS
104my $IRT = $SOL_TIMEOUT;
105my $MRT = $SOL_MAX_RT;
106my $MRC = 1;	# DOCSIS says 4, RFC 3315 says it SHOULD be 0
107my $MRD = 0;
108
109# sleep a random amount of time between 0 and 1 second, required by RFC 3315
110# XXX: this seems pretty stupid
111sleep(rand($SOL_MAX_DELAY));
112
113my $RT;
114my $count = 0;
115my $mrd_end_time;
116if ($MRD != 0) {
117	$mrd_end_time = time() + $MRD;
118}
119my $reply_msg;
120do {
121	# create our socket, and send our Solicit
122	socket(SOCK, PF_INET6, SOCK_DGRAM, getprotobyname('udp')) || die;
123	my $addr = inet_pton(AF_INET6, $All_DHCP_Servers);
124	my $packet = $msg->packet();
125	my $send_ret = send(SOCK, $packet, 0,
126			    pack_sockaddr_in6($server_port, $addr));
127	if (not defined($send_ret)) {
128		printf STDERR
129			"Error \%d sending DHCPv6 Solicit message;\n\%s\n",
130			0+$ERRNO, $ERRNO;
131		exit(1);
132	} elsif ($send_ret != length($packet)) {
133		print STDERR "Unable to send entire DHCPv6 Solicit message.\n";
134		exit(1);
135	}
136	$count++;
137
138	my $RAND = rand(0.2) - 0.1;
139	if (defined $RT) {
140		$RT = 2*$RT + $RAND*$RT;
141		if (($RT > $MRT) && ($MRT != 0)) {
142			$RT = $MRT + $RAND*$RT;
143		}
144	} else {
145		$RT = $IRT + $RAND*$IRT;
146	}
147
148	my $rt_end_time = time() + $RT;
149	if (defined($mrd_end_time) && ($mrd_end_time > $rt_end_time)) {
150		$rt_end_time = $mrd_end_time;
151	}
152
153	for (;;) {
154		my $timeout = $rt_end_time - time();
155		if ($timeout < 0) {
156#			print STDERR "Timeout waiting for DHCPv6 Advertise ",
157#				"or Reply message.\n";
158			last;
159		}
160
161		my @ready = IO::Select->new(\*SOCK)->can_read($timeout);
162
163		if (@ready) {
164			my $reply;
165			my $recv_ret;
166
167			$recv_ret = recv(SOCK, $reply, 1500, 0);
168			if (not defined $recv_ret) {
169				printf STDERR
170					"Error \%d receiving DHCPv6 " .
171						"message;\n\%s\n",
172					0+$ERRNO, $ERRNO;
173				exit(1);
174			}
175
176			$reply_msg = dhcp_client::msg::decode($reply);
177			if (($reply_msg->{msg_type} == $MSG_ADVERTISE) ||
178			    ($reply_msg->{msg_type} == $MSG_REPLY)) {
179			    	last;
180			}
181		}
182	}
183
184} until ($reply_msg ||
185	 (($MRC != 0) && ($count > $MRC)) ||
186	 (defined($mrd_end_time) && ($mrd_end_time > time())));
187
188unless ($reply_msg) {
189	if (($MRC != 0) && ($count >= $MRC)) {
190		print STDERR
191			"No reply after maximum retransmission count.\n";
192	} else {
193		print STDERR
194			"No reply after maximum retransmission duration.\n";
195	}
196}
197
198if ($reply_msg && ($reply_msg->{msg_type} == $MSG_REPLY)) {
199	print "Got DHCPv6 Reply message.\n";
200	exit(0);
201}
202
203#$Data::Dumper::Useqq = 1;
204#print Dumper($msg), "\n";
205#print Dumper($msg->packet()), "\n";
206#
207#print "packet length: ", length($msg->packet()), "\n";
208
209