Repository navigation
Expand file tree
/
Copy patharp.c
More file actions
443 lines (364 loc) · 11.9 KB
/
Copy patharp.c
File metadata and controls
443 lines (364 loc) · 11.9 KB
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
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
/*
* Copyright (c) 2002, 2003, 2004 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
*
* Copyright (c) 2000, 2001, 2002 Dug Song <dugsong@monkey.org>
* All rights reserved, all wrongs reversed.
*
* 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. The name of the authors may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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.
*/
#include <sys/types.h>
#include <sys/param.h>
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/ioctl.h>
#include <sys/tree.h>
#include <sys/queue.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <assert.h>
#include <event.h>
#include <pcap.h>
#include <dnet.h>
#include "honeyd.h"
#include "template.h"
#include "router.h"
#include "interface.h"
#include "arp.h"
#include "debug.h"
#define ARP_MAX_ACTIVE 600
/* Exported */
int need_arp = 0; /* We set this if we need to listen to arp traffic */
/* Imported */
extern struct network *reverse;
/* Internal */
/* For the physical (IP) address */
static SPLAY_HEAD(paarptree, arp_req) pa_arp_reqs;
static int
pa_compare(struct arp_req *a, struct arp_req *b)
{
return (addr_cmp(&a->pa, &b->pa));
}
SPLAY_PROTOTYPE(paarptree, arp_req, next_pa, pa_compare);
SPLAY_GENERATE(paarptree, arp_req, next_pa, pa_compare);
/* For the hardware address */
static SPLAY_HEAD(haarptree, arp_req) ha_arp_reqs;
static int
ha_compare(struct arp_req *a, struct arp_req *b)
{
return (addr_cmp(&a->ha, &b->ha));
}
SPLAY_PROTOTYPE(haarptree, arp_req, next_ha, ha_compare);
SPLAY_GENERATE(haarptree, arp_req, next_ha, ha_compare);
void
arp_init(void)
{
SPLAY_INIT(&pa_arp_reqs);
SPLAY_INIT(&ha_arp_reqs);
}
static void
arp_send(eth_t *eth, int op,
struct addr *sha, struct addr *spa,
struct addr *tha, struct addr *tpa)
{
u_char pkt[ETH_HDR_LEN + ARP_HDR_LEN + ARP_ETHIP_LEN];
eth_pack_hdr(pkt, tha->addr_eth, sha->addr_eth, ETH_TYPE_ARP);
arp_pack_hdr_ethip(pkt + ETH_HDR_LEN, op, sha->addr_eth,
spa->addr_ip, tha->addr_eth, tpa->addr_ip);
if (op == ARP_OP_REQUEST) {
syslog(LOG_DEBUG, "%s: who-has %s tell %s", __func__,
addr_ntoa(tpa), addr_ntoa(spa));
} else if (op == ARP_OP_REPLY) {
syslog(LOG_INFO, "arp reply %s is-at %s",
addr_ntoa(spa), addr_ntoa(sha));
}
if (eth_send(eth, pkt, sizeof(pkt)) != sizeof(pkt))
syslog(LOG_ERR, "couldn't send packet: %m");
}
void
arp_free(struct arp_req *req)
{
SPLAY_REMOVE(paarptree, &pa_arp_reqs, req);
if (SPLAY_FIND(haarptree, &ha_arp_reqs, req) != NULL)
SPLAY_REMOVE(haarptree, &ha_arp_reqs, req);
evtimer_del(req->active);
evtimer_del(req->discover);
free(req);
}
static void
arp_timeout(int fd, short event, void *arg)
{
struct arp_req *req = arg;
syslog(LOG_DEBUG, "%s: expiring %s", __func__, addr_ntoa(&req->pa));
arp_free(req);
}
static void
arp_discover(struct arp_req *req, struct addr *ha)
{
struct interface *inter = req->inter;
struct timeval tv = {0, 500000};
struct addr bcast;
addr_pack(&bcast, ADDR_TYPE_ETH, ETH_ADDR_BITS,
ETH_ADDR_BROADCAST, ETH_ADDR_LEN);
if (ha != NULL) {
memcpy(&req->ha, ha, sizeof(*ha));
// Don't insert the broadcast MAC address into the ARP table
if (0 != memcmp(&ha->__addr_u, &bcast.__addr_u, ETH_ADDR_LEN))
{
/*
* We might get multiple packets, so we need to remove
* the entry before we can insert it again.
*/
if (SPLAY_FIND(haarptree, &ha_arp_reqs, req) != NULL)
SPLAY_REMOVE(haarptree, &ha_arp_reqs, req);
if (SPLAY_FIND(haarptree, &ha_arp_reqs, req) == NULL)
SPLAY_INSERT(haarptree, &ha_arp_reqs, req);
}
}
if ((req->cnt < 2) && (inter != NULL)) {
arp_send(inter->if_eth, ARP_OP_REQUEST,
&req->src_ha, /* ethernet */
&req->src_pa, /* ip */
&req->ha, &req->pa);
/* XXX - use reversemap on networks to find router ip */
evtimer_add(req->discover, &tv);
} else
(*req->cb)(req, 0, req->arg);
req->cnt++;
}
static void
arp_discovercb(int fd, short event, void *arg)
{
struct arp_req *req = arg;
arp_discover(req, NULL);
}
/* Find an arp entry based on the corresponding IP or hardware address */
struct arp_req *
arp_find(struct addr *addr)
{
struct arp_req tmp, *res = NULL;
if (addr->addr_type == ADDR_TYPE_IP) {
tmp.pa = *addr;
res = SPLAY_FIND(paarptree, &pa_arp_reqs, &tmp);
} else if (addr->addr_type == ADDR_TYPE_ETH) {
tmp.ha = *addr;
res = SPLAY_FIND(haarptree, &ha_arp_reqs, &tmp);
} else {
syslog(LOG_ERR, "%s: lookup for unsupported address type", __func__);
exit(EXIT_FAILURE);
}
return (res);
}
/*
* Allocates a new arp info structure and inserts it into the appropriate
* trees so that we can find it later.
*/
struct arp_req *
arp_new(struct interface *inter,
struct addr *src_pa, struct addr *src_ha,
struct addr *pa, struct addr *ha)
{
struct arp_req *req;
if ((req = calloc(1, sizeof(*req))) == NULL)
return (NULL);
req->inter = inter;
if (src_pa != NULL)
req->src_pa = *src_pa;
if (src_ha != NULL)
req->src_ha = *src_ha;
if (pa != NULL) {
req->pa = *pa;
SPLAY_INSERT(paarptree, &pa_arp_reqs, req);
}
if (ha != NULL) {
req->ha = *ha;
assert (SPLAY_FIND(haarptree, &ha_arp_reqs, req) == NULL);
SPLAY_INSERT(haarptree, &ha_arp_reqs, req);
}
req->active = evtimer_new(libevent_base, arp
8000
_timeout, req);
req->discover = evtimer_new(libevent_base, arp_discovercb, req);
return (req);
}
/* Request the resolution of an IP address to an ethernet address */
void
arp_request(struct interface *inter,
struct addr *src_pa, struct addr *src_ha,
struct addr *addr, void (*cb)(struct arp_req *, int, void *), void *arg)
{
struct arp_req *req;
struct addr bcast;
struct timeval tv;
if ((req = arp_new(inter, src_pa, src_ha, addr, NULL)) == NULL) {
syslog(LOG_ERR, "calloc: %m");
return;
}
req->cb = cb;
req->arg = arg;
timerclear(&tv);
tv.tv_sec = ARP_MAX_ACTIVE;
evtimer_add(req->active, &tv);
addr_pack(&bcast, ADDR_TYPE_ETH, ETH_ADDR_BITS,
ETH_ADDR_BROADCAST, ETH_ADDR_LEN);
arp_discover(req, &bcast);
}
void
arp_recv_cb(u_char *u, const struct pcap_pkthdr *pkthdr, const u_char *pkt)
{
struct interface *inter = (struct interface *)u;
struct template *tmpl;
struct arp_hdr *arp;
struct arp_ethip *ethip;
struct arp_req *req;
struct arp_entry src, dst;
struct addr *reply_sha;
if (pkthdr->caplen < inter->if_dloff + ARP_HDR_LEN + ARP_ETHIP_LEN)
return;
arp = (struct arp_hdr *)(pkt + inter->if_dloff);
ethip = (struct arp_ethip *)(arp + 1);
addr_pack(&src.arp_ha, ADDR_TYPE_ETH, ETH_ADDR_BITS,
ethip->ar_sha, ETH_ADDR_LEN);
addr_pack(&src.arp_pa, ADDR_TYPE_IP, IP_ADDR_BITS,
ethip->ar_spa, IP_ADDR_LEN);
/* Check that protocol type is IP */
if (ntohs(arp->ar_pro) != ARP_PRO_IP)
return;
/* Check that hardware address format is correct */
if (ntohs(arp->ar_hrd) != ARP_HRD_ETH && ntohs(arp->ar_hrd) != ARP_HRD_IEEE802)
return;
/* Check that hardware address length is valid for MAC */
if (arp->ar_hln != ETH_ADDR_LEN)
return;
/* Check that protocol address length is valid for IPv4 */
if (arp->ar_pln != IP_ADDR_LEN)
return;
/* Make sure the sender wasn't the broadcast address */
if (src.arp_pa.addr_ip == IP_ADDR_BROADCAST)
return;
/* Make sure the sender wasn't the loopback address */
if (src.arp_pa.addr_ip == IP_ADDR_LOOPBACK)
return;
switch (ntohs(arp->ar_op)) {
case ARP_OP_REQUEST:
addr_pack(&dst.arp_pa, ADDR_TYPE_IP, IP_ADDR_BITS,
ðip->ar_tpa, IP_ADDR_LEN);
/* Check if we are responsible for this network or address */
req = arp_find(&dst.arp_pa);
if (network_lookup(reverse, &dst.arp_pa) == NULL &&
req == NULL) {
ignore:
DFPRINTF(2, (stderr,
"ignoring arp request on %s for %s: %p\n",
inter->if_ent.intf_name,
addr_ntoa(&dst.arp_pa), req));
return;
}
/*
* If we discovered this address ourselves, we do not
* want to send a reply - although we could.
*/
if (req != NULL && (req->flags & ARP_EXTERNAL))
goto ignore;
tmpl = template_find(addr_ntoa(&dst.arp_pa));
/*
* If this template points to an external host,
* we do not answer for it. It has to answer itself.
*/
if (tmpl != NULL && (tmpl->flags & TEMPLATE_EXTERNAL))
goto ignore;
/*
* We need to either reply with our interface address or
* with the address configured in the template.
*/
if (tmpl == NULL || tmpl->ethernet_addr == NULL)
reply_sha = &inter->if_ent.intf_link_addr;
else
reply_sha = tmpl->ethernet_addr;
/* Send reply */
arp_send(inter->if_eth, ARP_OP_REPLY,
reply_sha, &dst.arp_pa,
&src.arp_ha, &src.arp_pa);
break;
case ARP_OP_REPLY:
addr_pack(&src.arp_pa, ADDR_TYPE_IP, IP_ADDR_BITS,
ðip->ar_spa, IP_ADDR_LEN);
if ((req = arp_find(&src.arp_pa)) != NULL) {
addr_pack(&req->ha, ADDR_TYPE_ETH, ETH_ADDR_BITS,
ethip->ar_sha, ETH_ADDR_LEN);
/*
* Ignore arp replies that we generate ourselves.
* Because we fake ethernet mac addresses so
* successfully or pcap filter does not know that
* this is a Honeyd packet.
*/
if ( !(req->flags & ARP_INTERNAL) ) {
/* Signal success */
req->flags |= ARP_EXTERNAL;
req->cnt = ARP_REQUEST_SUCESS;
assert(req->cb != NULL);
(*req->cb)(req, 1, req->arg);
evtimer_del(req->discover);
syslog(LOG_DEBUG, "%s: %s at %s", __func__,
addr_ntoa(&req->pa), addr_ntoa(&req->ha));
}
}
break;
}
}