1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
|
/* bootp.c
BOOTP Protocol support. */
/*
* Copyright (c) 1995, 1996 The Internet Software Consortium.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of The Internet Software Consortium nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
* CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#ifndef lint
static char copyright[] =
"$Id: bootp.c,v 1.1 1998/08/18 03:43:34 deraadt Exp $ Copyright (c) 1995, 1996 The Internet Software Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
void bootp (packet)
struct packet *packet;
{
int result;
struct host_decl *hp;
struct host_decl *host = (struct host_decl *)0;
struct packet outgoing;
struct dhcp_packet raw;
struct sockaddr_in to;
struct in_addr from;
struct hardware hto;
struct tree_cache *options [256];
struct subnet *subnet;
struct lease *lease;
struct iaddr ip_address;
int i;
if (packet -> raw -> op != BOOTREQUEST)
return;
note ("BOOTREQUEST from %s via %s",
print_hw_addr (packet -> raw -> htype,
packet -> raw -> hlen,
packet -> raw -> chaddr),
packet -> raw -> giaddr.s_addr
? inet_ntoa (packet -> raw -> giaddr)
: packet -> interface -> name);
if (!locate_network (packet))
return;
hp = find_hosts_by_haddr (packet -> raw -> htype,
packet -> raw -> chaddr,
packet -> raw -> hlen);
lease = find_lease (packet, packet -> shared_network, 0);
/* Find an IP address in the host_decl that matches the
specified network. */
if (hp)
subnet = find_host_for_network (&hp, &ip_address,
packet -> shared_network);
else
subnet = (struct subnet *)0;
if (!subnet) {
/* We didn't find an applicable host declaration.
Just in case we may be able to dynamically assign
an address, see if there's a host declaration
that doesn't have an ip address associated with it. */
if (hp) {
for (; hp; hp = hp -> n_ipaddr) {
if (!hp -> fixed_addr) {
host = hp;
break;
}
}
}
if (host && (!host -> group -> allow_booting)) {
note ("Ignoring excluded BOOTP client %s",
host -> name);
return;
}
if (host && (!host -> group -> allow_bootp)) {
note ("Ignoring BOOTP request from client %s",
host -> name);
return;
}
/* If we've been told not to boot unknown clients,
and we didn't find any host record for this client,
ignore it. */
if (!host && !(packet -> shared_network ->
group -> boot_unknown_clients)) {
note ("Ignoring unknown BOOTP client %s via %s",
print_hw_addr (packet -> raw -> htype,
packet -> raw -> hlen,
packet -> raw -> chaddr),
packet -> raw -> giaddr.s_addr
? inet_ntoa (packet -> raw -> giaddr)
: packet -> interface -> name);
return;
}
/* If we've been told not to boot with bootp on this
network, ignore it. */
if (!host &&
!(packet -> shared_network -> group -> allow_bootp)) {
note ("Ignoring BOOTP request from client %s via %s",
print_hw_addr (packet -> raw -> htype,
packet -> raw -> hlen,
packet -> raw -> chaddr),
packet -> raw -> giaddr.s_addr
? inet_ntoa (packet -> raw -> giaddr)
: packet -> interface -> name);
return;
}
/* If the packet is from a host we don't know and there
are no dynamic bootp addresses on the network it came
in on, drop it on the floor. */
if (!(packet -> shared_network -> group -> dynamic_bootp)) {
lose:
note ("No applicable record for BOOTP host %s via %s",
print_hw_addr (packet -> raw -> htype,
packet -> raw -> hlen,
packet -> raw -> chaddr),
packet -> raw -> giaddr.s_addr
? inet_ntoa (packet -> raw -> giaddr)
: packet -> interface -> name);
return;
}
/* If a lease has already been assigned to this client
and it's still okay to use dynamic bootp on
that lease, reassign it. */
if (lease) {
/* If this lease can be used for dynamic bootp,
do so. */
if ((lease -> flags & DYNAMIC_BOOTP_OK)) {
/* If it's not a DYNAMIC_BOOTP lease,
release it before reassigning it
so that we don't get a lease
conflict. */
if (!(lease -> flags & BOOTP_LEASE))
release_lease (lease);
lease -> host = host;
ack_lease (packet, lease, 0, 0);
return;
}
/* If dynamic BOOTP is no longer allowed for
this lease, set it free. */
release_lease (lease);
}
/* If there are dynamic bootp addresses that might be
available, try to snag one. */
for (lease = packet -> shared_network -> last_lease;
lease && lease -> ends <= cur_time;
lease = lease -> prev) {
if ((lease -> flags & DYNAMIC_BOOTP_OK)) {
lease -> host = host;
ack_lease (packet, lease, 0, 0);
return;
}
}
goto lose;
}
/* Make sure we're allowed to boot this client. */
if (hp && (!hp -> group -> allow_booting)) {
note ("Ignoring excluded BOOTP client %s",
hp -> name);
return;
}
/* Make sure we're allowed to boot this client with bootp. */
if (hp && (!hp -> group -> allow_bootp)) {
note ("Ignoring BOOTP request from client %s",
hp -> name);
return;
}
/* Set up the outgoing packet... */
memset (&outgoing, 0, sizeof outgoing);
memset (&raw, 0, sizeof raw);
outgoing.raw = &raw;
/* If we didn't get a known vendor magic number on the way in,
just copy the input options to the output. */
if (!packet -> options_valid) {
memcpy (outgoing.raw -> options,
packet -> raw -> options, DHCP_OPTION_LEN);
outgoing.packet_length = BOOTP_MIN_LEN;
} else {
/* Come up with a list of options that we want to send
to this client. Start with the per-subnet options,
and then override those with client-specific
options. */
memcpy (options, subnet -> group -> options, sizeof options);
for (i = 0; i < 256; i++) {
if (hp -> group -> options [i])
options [i] = hp -> group -> options [i];
}
/* Pack the options into the buffer. Unlike DHCP, we
can't pack options into the filename and server
name buffers. */
outgoing.packet_length =
cons_options (packet, outgoing.raw, options, 0, 0, 1);
if (outgoing.packet_length < BOOTP_MIN_LEN)
outgoing.packet_length = BOOTP_MIN_LEN;
}
/* Take the fields that we care about... */
raw.op = BOOTREPLY;
raw.htype = packet -> raw -> htype;
raw.hlen = packet -> raw -> hlen;
memcpy (raw.chaddr, packet -> raw -> chaddr, raw.hlen);
memset (&raw.chaddr [raw.hlen], 0,
(sizeof raw.chaddr) - raw.hlen);
raw.hops = packet -> raw -> hops;
raw.xid = packet -> raw -> xid;
raw.secs = packet -> raw -> secs;
raw.flags = 0;
raw.ciaddr = packet -> raw -> ciaddr;
memcpy (&raw.yiaddr, ip_address.iabuf, sizeof raw.yiaddr);
/* Figure out the address of the next server. */
if (hp && hp -> group -> next_server.len)
memcpy (&raw.siaddr, hp -> group -> next_server.iabuf, 4);
else if (subnet -> group -> next_server.len)
memcpy (&raw.siaddr, subnet -> group -> next_server.iabuf, 4);
else if (subnet -> interface_address.len)
memcpy (&raw.siaddr, subnet -> interface_address.iabuf, 4);
else
raw.siaddr = packet -> interface -> primary_address;
raw.giaddr = packet -> raw -> giaddr;
if (hp -> group -> server_name) {
strncpy (raw.sname, hp -> group -> server_name,
(sizeof raw.sname) - 1);
raw.sname [(sizeof raw.sname) - 1] = 0;
}
/* If the client requested a specific boot file, echo it
back per RFC951; some clients are unable to boot properly
without this (e.g. DECstations). */
if (packet -> raw -> file[0] != '\0')
memcpy (raw.file, packet -> raw -> file, sizeof raw.file);
else if (hp -> group -> filename) {
strncpy (raw.file, hp -> group -> filename,
(sizeof raw.file) - 1);
raw.file [(sizeof raw.file) - 1] = 0;
}
/* Set up the hardware destination address... */
hto.htype = packet -> raw -> htype;
hto.hlen = packet -> raw -> hlen;
memcpy (hto.haddr, packet -> raw -> chaddr, hto.hlen);
from = packet -> interface -> primary_address;
/* Report what we're doing... */
note ("BOOTREPLY for %s to %s (%s) via %s",
piaddr (ip_address), hp -> name,
print_hw_addr (packet -> raw -> htype,
packet -> raw -> hlen,
packet -> raw -> chaddr),
packet -> raw -> giaddr.s_addr
? inet_ntoa (packet -> raw -> giaddr)
: packet -> interface -> name);
/* Set up the parts of the address that are in common. */
to.sin_family = AF_INET;
#ifdef HAVE_SA_LEN
to.sin_len = sizeof to;
#endif
memset (to.sin_zero, 0, sizeof to.sin_zero);
/* If this was gatewayed, send it back to the gateway... */
if (raw.giaddr.s_addr) {
to.sin_addr = raw.giaddr;
to.sin_port = local_port;
#ifdef USE_FALLBACK
result = send_fallback (&fallback_interface,
(struct packet *)0,
&raw, outgoing.packet_length,
from, &to, &hto);
if (result < 0)
warn ("send_fallback: %m");
return;
#endif
/* Otherwise, broadcast it on the local network. */
} else {
to.sin_addr.s_addr = INADDR_BROADCAST;
to.sin_port = remote_port; /* XXX */
}
errno = 0;
result = send_packet (packet -> interface,
packet, &raw, outgoing.packet_length,
from, &to, &hto);
if (result < 0)
warn ("send_packet: %m");
}
|
