summaryrefslogtreecommitdiffstats
path: root/contrib/libpcap/pcap-snit.c
blob: e6232c2e84205af2c18da4abe5c55c9eb53aff3c (plain)
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
444
445
/*
 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Modifications made to accommodate the new SunOS4.0 NIT facility by
 * Micky Liu, micky@cunixc.cc.columbia.edu, Columbia University in May, 1989.
 * This module now handles the STREAMS based NIT.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>
#include <sys/time.h>
#include <sys/timeb.h>
#include <sys/dir.h>
#include <sys/fcntlcom.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/stropts.h>

#include <net/if.h>
#include <net/nit.h>
#include <net/nit_if.h>
#include <net/nit_pf.h>
#include <net/nit_buf.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/if_ether.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/tcp.h>
#include <netinet/tcpip.h>

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include "pcap-int.h"

#ifdef HAVE_OS_PROTO_H
#include "os-proto.h"
#endif

/*
 * The chunk size for NIT.  This is the amount of buffering
 * done for read calls.
 */
#define CHUNKSIZE (2*1024)

/*
 * The total buffer space used by NIT.
 */
#define BUFSPACE (4*CHUNKSIZE)

/* Forwards */
static int nit_setflags(int, int, int, char *);

/*
 * Private data for capturing on STREAMS NIT devices.
 */
struct pcap_snit {
	struct pcap_stat stat;
};

static int
pcap_stats_snit(pcap_t *p, struct pcap_stat *ps)
{
	struct pcap_snit *psn = p->priv;

	/*
	 * "ps_recv" counts packets handed to the filter, not packets
	 * that passed the filter.  As filtering is done in userland,
	 * this does not include packets dropped because we ran out
	 * of buffer space.
	 *
	 * "ps_drop" counts packets dropped inside the "/dev/nit"
	 * device because of flow control requirements or resource
	 * exhaustion; it doesn't count packets dropped by the
	 * interface driver, or packets dropped upstream.  As filtering
	 * is done in userland, it counts packets regardless of whether
	 * they would've passed the filter.
	 *
	 * These statistics don't include packets not yet read from the
	 * kernel by libpcap or packets not yet read from libpcap by the
	 * application.
	 */
	*ps = psn->stat;
	return (0);
}

static int
pcap_read_snit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
{
	struct pcap_snit *psn = p->priv;
	register int cc, n;
	register u_char *bp, *cp, *ep;
	register struct nit_bufhdr *hdrp;
	register struct nit_iftime *ntp;
	register struct nit_iflen *nlp;
	register struct nit_ifdrops *ndp;
	register int caplen;

	cc = p->cc;
	if (cc == 0) {
		cc = read(p->fd, (char *)p->buffer, p->bufsize);
		if (cc < 0) {
			if (errno == EWOULDBLOCK)
				return (0);
			snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
				pcap_strerror(errno));
			return (-1);
		}
		bp = p->buffer;
	} else
		bp = p->bp;

	/*
	 * loop through each snapshot in the chunk
	 */
	n = 0;
	ep = bp + cc;
	while (bp < ep) {
		/*
		 * Has "pcap_breakloop()" been called?
		 * If so, return immediately - if we haven't read any
		 * packets, clear the flag and return -2 to indicate
		 * that we were told to break out of the loop, otherwise
		 * leave the flag set, so that the *next* call will break
		 * out of the loop without having read any packets, and
		 * return the number of packets we've processed so far.
		 */
		if (p->break_loop) {
			if (n == 0) {
				p->break_loop = 0;
				return (-2);
			} else {
				p->bp = bp;
				p->cc = ep - bp;
				return (n);
			}
		}

		++psn->stat.ps_recv;
		cp = bp;

		/* get past NIT buffer  */
		hdrp = (struct nit_bufhdr *)cp;
		cp += sizeof(*hdrp);

		/* get past NIT timer   */
		ntp = (struct nit_iftime *)cp;
		cp += sizeof(*ntp);

		ndp = (struct nit_ifdrops *)cp;
		psn->stat.ps_drop = ndp->nh_drops;
		cp += sizeof *ndp;

		/* get past packet len  */
		nlp = (struct nit_iflen *)cp;
		cp += sizeof(*nlp);

		/* next snapshot        */
		bp += hdrp->nhb_totlen;

		caplen = nlp->nh_pktlen;
		if (caplen > p->snapshot)
			caplen = p->snapshot;

		if (bpf_filter(p->fcode.bf_insns, cp, nlp->nh_pktlen, caplen)) {
			struct pcap_pkthdr h;
			h.ts = ntp->nh_timestamp;
			h.len = nlp->nh_pktlen;
			h.caplen = caplen;
			(*callback)(user, &h, cp);
			if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {
				p->cc = ep - bp;
				p->bp = bp;
				return (n);
			}
		}
	}
	p->cc = 0;
	return (n);
}

static int
pcap_inject_snit(pcap_t *p, const void *buf, size_t size)
{
	struct strbuf ctl, data;
	
	/*
	 * XXX - can we just do
	 *
	ret = write(pd->f, buf, size);
	 */
	ctl.len = sizeof(*sa);	/* XXX - what was this? */
	ctl.buf = (char *)sa;
	data.buf = buf;
	data.len = size;
	ret = putmsg(p->fd, &ctl, &data);
	if (ret == -1) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s",
		    pcap_strerror(errno));
		return (-1);
	}
	return (ret);
}

static int
nit_setflags(pcap_t *p)
{
	bpf_u_int32 flags;
	struct strioctl si;
	u_int zero = 0;
	struct timeval timeout;

	if (p->opt.immediate) {
		/*
		 * Set the chunk size to zero, so that chunks get sent
		 * up immediately.
		 */
		si.ic_cmd = NIOCSCHUNK;
		si.ic_len = sizeof(zero);
		si.ic_dp = (char *)&zero;
		if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSCHUNK: %s",
			    pcap_strerror(errno));
			return (-1);
		}
	}
	si.ic_timout = INFTIM;
	if (p->opt.timeout != 0) {
		timeout.tv_sec = p->opt.timeout / 1000;
		timeout.tv_usec = (p->opt.timeout * 1000) % 1000000;
		si.ic_cmd = NIOCSTIME;
		si.ic_len = sizeof(timeout);
		si.ic_dp = (char *)&timeout;
		if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSTIME: %s",
			    pcap_strerror(errno));
			return (-1);
		}
	}
	flags = NI_TIMESTAMP | NI_LEN | NI_DROPS;
	if (p->opt.promisc)
		flags |= NI_PROMISC;
	si.ic_cmd = NIOCSFLAGS;
	si.ic_len = sizeof(flags);
	si.ic_dp = (char *)&flags;
	if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSFLAGS: %s",
		    pcap_strerror(errno));
		return (-1);
	}
	return (0);
}

static int
pcap_activate_snit(pcap_t *p)
{
	struct strioctl si;		/* struct for ioctl() */
	struct ifreq ifr;		/* interface request struct */
	int chunksize = CHUNKSIZE;
	int fd;
	static char dev[] = "/dev/nit";

	if (p->opt.rfmon) {
		/*
		 * No monitor mode on SunOS 4.x (no Wi-Fi devices on
		 * hardware supported by SunOS 4.x).
		 */
		return (PCAP_ERROR_RFMON_NOTSUP);
	}

	if (p->snapshot < 96)
		/*
		 * NIT requires a snapshot length of at least 96.
		 */
		p->snapshot = 96;

	/*
	 * Initially try a read/write open (to allow the inject
	 * method to work).  If that fails due to permission
	 * issues, fall back to read-only.  This allows a
	 * non-root user to be granted specific access to pcap
	 * capabilities via file permissions.
	 *
	 * XXX - we should have an API that has a flag that
	 * controls whether to open read-only or read-write,
	 * so that denial of permission to send (or inability
	 * to send, if sending packets isn't supported on
	 * the device in question) can be indicated at open
	 * time.
	 */
	p->fd = fd = open(dev, O_RDWR);
	if (fd < 0 && errno == EACCES)
		p->fd = fd = open(dev, O_RDONLY);
	if (fd < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s", dev,
		    pcap_strerror(errno));
		goto bad;
	}

	/* arrange to get discrete messages from the STREAM and use NIT_BUF */
	if (ioctl(fd, I_SRDOPT, (char *)RMSGD) < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "I_SRDOPT: %s",
		    pcap_strerror(errno));
		goto bad;
	}
	if (ioctl(fd, I_PUSH, "nbuf") < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "push nbuf: %s",
		    pcap_strerror(errno));
		goto bad;
	}
	/* set the chunksize */
	si.ic_cmd = NIOCSCHUNK;
	si.ic_timout = INFTIM;
	si.ic_len = sizeof(chunksize);
	si.ic_dp = (char *)&chunksize;
	if (ioctl(fd, I_STR, (char *)&si) < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSCHUNK: %s",
		    pcap_strerror(errno));
		goto bad;
	}

	/* request the interface */
	strncpy(ifr.ifr_name, p->opt.source, sizeof(ifr.ifr_name));
	ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0';
	si.ic_cmd = NIOCBIND;
	si.ic_len = sizeof(ifr);
	si.ic_dp = (char *)&ifr;
	if (ioctl(fd, I_STR, (char *)&si) < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCBIND: %s: %s",
			ifr.ifr_name, pcap_strerror(errno));
		goto bad;
	}

	/* set the snapshot length */
	si.ic_cmd = NIOCSSNAP;
	si.ic_len = sizeof(p->snapshot);
	si.ic_dp = (char *)&p->snapshot;
	if (ioctl(fd, I_STR, (char *)&si) < 0) {
		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSSNAP: %s",
		    pcap_strerror(errno));
		goto bad;
	}
	if (nit_setflags(p) < 0)
		goto bad;

	(void)ioctl(fd, I_FLUSH, (char *)FLUSHR);
	/*
	 * NIT supports only ethernets.
	 */
	p->linktype = DLT_EN10MB;

	p->bufsize = BUFSPACE;
	p->buffer = (u_char *)malloc(p->bufsize);
	if (p->buffer == NULL) {
		strlcpy(p->errbuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
		goto bad;
	}

	/*
	 * "p->fd" is an FD for a STREAMS device, so "select()" and
	 * "poll()" should work on it.
	 */
	p->selectable_fd = p->fd;

	/*
	 * This is (presumably) a real Ethernet capture; give it a
	 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
	 * that an application can let you choose it, in case you're
	 * capturing DOCSIS traffic that a Cisco Cable Modem
	 * Termination System is putting out onto an Ethernet (it
	 * doesn't put an Ethernet header onto the wire, it puts raw
	 * DOCSIS frames out on the wire inside the low-level
	 * Ethernet framing).
	 */
	p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
	/*
	 * If that fails, just leave the list empty.
	 */
	if (p->dlt_list != NULL) {
		p->dlt_list[0] = DLT_EN10MB;
		p->dlt_list[1] = DLT_DOCSIS;
		p->dlt_count = 2;
	}

	p->read_op = pcap_read_snit;
	p->inject_op = pcap_inject_snit;
	p->setfilter_op = install_bpf_program;	/* no kernel filtering */
	p->setdirection_op = NULL;	/* Not implemented. */
	p->set_datalink_op = NULL;	/* can't change data link type */
	p->getnonblock_op = pcap_getnonblock_fd;
	p->setnonblock_op = pcap_setnonblock_fd;
	p->stats_op = pcap_stats_snit;

	return (0);
 bad:
	pcap_cleanup_live_common(p);
	return (PCAP_ERROR);
}

pcap_t *
pcap_create_interface(const char *device, char *ebuf)
{
	pcap_t *p;

	p = pcap_create_common(device, ebuf, sizeof (struct pcap_snit));
	if (p == NULL)
		return (NULL);

	p->activate_op = pcap_activate_snit;
	return (p);
}

int
pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
{
	return (0);
}
OpenPOWER on IntegriCloud