1/*
2 * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
16 * written permission.
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 *
21 * Modifications made to accommodate the new SunOS4.0 NIT facility by
22 * Micky Liu, micky@cunixc.cc.columbia.edu, Columbia University in May, 1989.
23 * This module now handles the STREAMS based NIT.
24 */
25
26#ifndef lint
27static const char rcsid[] _U_ =
28    "@(#) $Header: /tcpdump/master/libpcap/pcap-snit.c,v 1.77 2008-04-14 20:40:58 guy Exp $ (LBL)";
29#endif
30
31#ifdef HAVE_CONFIG_H
32#include "config.h"
33#endif
34
35#include <sys/types.h>
36#include <sys/time.h>
37#include <sys/timeb.h>
38#include <sys/dir.h>
39#include <sys/fcntlcom.h>
40#include <sys/file.h>
41#include <sys/ioctl.h>
42#include <sys/socket.h>
43#include <sys/stropts.h>
44
45#include <net/if.h>
46#include <net/nit.h>
47#include <net/nit_if.h>
48#include <net/nit_pf.h>
49#include <net/nit_buf.h>
50
51#include <netinet/in.h>
52#include <netinet/in_systm.h>
53#include <netinet/ip.h>
54#include <netinet/if_ether.h>
55#include <netinet/ip_var.h>
56#include <netinet/udp.h>
57#include <netinet/udp_var.h>
58#include <netinet/tcp.h>
59#include <netinet/tcpip.h>
60
61#include <ctype.h>
62#include <errno.h>
63#include <stdio.h>
64#include <string.h>
65#include <unistd.h>
66
67#include "pcap-int.h"
68
69#ifdef HAVE_OS_PROTO_H
70#include "os-proto.h"
71#endif
72
73/*
74 * The chunk size for NIT.  This is the amount of buffering
75 * done for read calls.
76 */
77#define CHUNKSIZE (2*1024)
78
79/*
80 * The total buffer space used by NIT.
81 */
82#define BUFSPACE (4*CHUNKSIZE)
83
84/* Forwards */
85static int nit_setflags(int, int, int, char *);
86
87/*
88 * Private data for capturing on STREAMS NIT devices.
89 */
90struct pcap_snit {
91	struct pcap_stat stat;
92};
93
94static int
95pcap_stats_snit(pcap_t *p, struct pcap_stat *ps)
96{
97	struct pcap_snit *psn = p->priv;
98
99	/*
100	 * "ps_recv" counts packets handed to the filter, not packets
101	 * that passed the filter.  As filtering is done in userland,
102	 * this does not include packets dropped because we ran out
103	 * of buffer space.
104	 *
105	 * "ps_drop" counts packets dropped inside the "/dev/nit"
106	 * device because of flow control requirements or resource
107	 * exhaustion; it doesn't count packets dropped by the
108	 * interface driver, or packets dropped upstream.  As filtering
109	 * is done in userland, it counts packets regardless of whether
110	 * they would've passed the filter.
111	 *
112	 * These statistics don't include packets not yet read from the
113	 * kernel by libpcap or packets not yet read from libpcap by the
114	 * application.
115	 */
116	*ps = psn->stat;
117	return (0);
118}
119
120static int
121pcap_read_snit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
122{
123	struct pcap_snit *psn = p->priv;
124	register int cc, n;
125	register u_char *bp, *cp, *ep;
126	register struct nit_bufhdr *hdrp;
127	register struct nit_iftime *ntp;
128	register struct nit_iflen *nlp;
129	register struct nit_ifdrops *ndp;
130	register int caplen;
131
132	cc = p->cc;
133	if (cc == 0) {
134		cc = read(p->fd, (char *)p->buffer, p->bufsize);
135		if (cc < 0) {
136			if (errno == EWOULDBLOCK)
137				return (0);
138			snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
139				pcap_strerror(errno));
140			return (-1);
141		}
142		bp = p->buffer;
143	} else
144		bp = p->bp;
145
146	/*
147	 * loop through each snapshot in the chunk
148	 */
149	n = 0;
150	ep = bp + cc;
151	while (bp < ep) {
152		/*
153		 * Has "pcap_breakloop()" been called?
154		 * If so, return immediately - if we haven't read any
155		 * packets, clear the flag and return -2 to indicate
156		 * that we were told to break out of the loop, otherwise
157		 * leave the flag set, so that the *next* call will break
158		 * out of the loop without having read any packets, and
159		 * return the number of packets we've processed so far.
160		 */
161		if (p->break_loop) {
162			if (n == 0) {
163				p->break_loop = 0;
164				return (-2);
165			} else {
166				p->bp = bp;
167				p->cc = ep - bp;
168				return (n);
169			}
170		}
171
172		++psn->stat.ps_recv;
173		cp = bp;
174
175		/* get past NIT buffer  */
176		hdrp = (struct nit_bufhdr *)cp;
177		cp += sizeof(*hdrp);
178
179		/* get past NIT timer   */
180		ntp = (struct nit_iftime *)cp;
181		cp += sizeof(*ntp);
182
183		ndp = (struct nit_ifdrops *)cp;
184		psn->stat.ps_drop = ndp->nh_drops;
185		cp += sizeof *ndp;
186
187		/* get past packet len  */
188		nlp = (struct nit_iflen *)cp;
189		cp += sizeof(*nlp);
190
191		/* next snapshot        */
192		bp += hdrp->nhb_totlen;
193
194		caplen = nlp->nh_pktlen;
195		if (caplen > p->snapshot)
196			caplen = p->snapshot;
197
198		if (bpf_filter(p->fcode.bf_insns, cp, nlp->nh_pktlen, caplen)) {
199			struct pcap_pkthdr h;
200			h.ts = ntp->nh_timestamp;
201			h.len = nlp->nh_pktlen;
202			h.caplen = caplen;
203			(*callback)(user, &h, cp);
204			if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {
205				p->cc = ep - bp;
206				p->bp = bp;
207				return (n);
208			}
209		}
210	}
211	p->cc = 0;
212	return (n);
213}
214
215static int
216pcap_inject_snit(pcap_t *p, const void *buf, size_t size)
217{
218	struct strbuf ctl, data;
219
220	/*
221	 * XXX - can we just do
222	 *
223	ret = write(pd->f, buf, size);
224	 */
225	ctl.len = sizeof(*sa);	/* XXX - what was this? */
226	ctl.buf = (char *)sa;
227	data.buf = buf;
228	data.len = size;
229	ret = putmsg(p->fd, &ctl, &data);
230	if (ret == -1) {
231		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s",
232		    pcap_strerror(errno));
233		return (-1);
234	}
235	return (ret);
236}
237
238static int
239nit_setflags(pcap_t *p)
240{
241	bpf_u_int32 flags;
242	struct strioctl si;
243	u_int zero = 0;
244	struct timeval timeout;
245
246	if (p->opt.immediate) {
247		/*
248		 * Set the chunk size to zero, so that chunks get sent
249		 * up immediately.
250		 */
251		si.ic_cmd = NIOCSCHUNK;
252		si.ic_len = sizeof(zero);
253		si.ic_dp = (char *)&zero;
254		if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
255			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSCHUNK: %s",
256			    pcap_strerror(errno));
257			return (-1);
258		}
259	}
260	si.ic_timout = INFTIM;
261	if (p->opt.timeout != 0) {
262		timeout.tv_sec = p->opt.timeout / 1000;
263		timeout.tv_usec = (p->opt.timeout * 1000) % 1000000;
264		si.ic_cmd = NIOCSTIME;
265		si.ic_len = sizeof(timeout);
266		si.ic_dp = (char *)&timeout;
267		if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
268			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSTIME: %s",
269			    pcap_strerror(errno));
270			return (-1);
271		}
272	}
273	flags = NI_TIMESTAMP | NI_LEN | NI_DROPS;
274	if (p->opt.promisc)
275		flags |= NI_PROMISC;
276	si.ic_cmd = NIOCSFLAGS;
277	si.ic_len = sizeof(flags);
278	si.ic_dp = (char *)&flags;
279	if (ioctl(p->fd, I_STR, (char *)&si) < 0) {
280		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSFLAGS: %s",
281		    pcap_strerror(errno));
282		return (-1);
283	}
284	return (0);
285}
286
287static int
288pcap_activate_snit(pcap_t *p)
289{
290	struct strioctl si;		/* struct for ioctl() */
291	struct ifreq ifr;		/* interface request struct */
292	int chunksize = CHUNKSIZE;
293	int fd;
294	static char dev[] = "/dev/nit";
295
296	if (p->opt.rfmon) {
297		/*
298		 * No monitor mode on SunOS 4.x (no Wi-Fi devices on
299		 * hardware supported by SunOS 4.x).
300		 */
301		return (PCAP_ERROR_RFMON_NOTSUP);
302	}
303
304	if (p->snapshot < 96)
305		/*
306		 * NIT requires a snapshot length of at least 96.
307		 */
308		p->snapshot = 96;
309
310	/*
311	 * Initially try a read/write open (to allow the inject
312	 * method to work).  If that fails due to permission
313	 * issues, fall back to read-only.  This allows a
314	 * non-root user to be granted specific access to pcap
315	 * capabilities via file permissions.
316	 *
317	 * XXX - we should have an API that has a flag that
318	 * controls whether to open read-only or read-write,
319	 * so that denial of permission to send (or inability
320	 * to send, if sending packets isn't supported on
321	 * the device in question) can be indicated at open
322	 * time.
323	 */
324	p->fd = fd = open(dev, O_RDWR);
325	if (fd < 0 && errno == EACCES)
326		p->fd = fd = open(dev, O_RDONLY);
327	if (fd < 0) {
328		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s", dev,
329		    pcap_strerror(errno));
330		goto bad;
331	}
332
333	/* arrange to get discrete messages from the STREAM and use NIT_BUF */
334	if (ioctl(fd, I_SRDOPT, (char *)RMSGD) < 0) {
335		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "I_SRDOPT: %s",
336		    pcap_strerror(errno));
337		goto bad;
338	}
339	if (ioctl(fd, I_PUSH, "nbuf") < 0) {
340		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "push nbuf: %s",
341		    pcap_strerror(errno));
342		goto bad;
343	}
344	/* set the chunksize */
345	si.ic_cmd = NIOCSCHUNK;
346	si.ic_timout = INFTIM;
347	si.ic_len = sizeof(chunksize);
348	si.ic_dp = (char *)&chunksize;
349	if (ioctl(fd, I_STR, (char *)&si) < 0) {
350		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSCHUNK: %s",
351		    pcap_strerror(errno));
352		goto bad;
353	}
354
355	/* request the interface */
356	strncpy(ifr.ifr_name, p->opt.source, sizeof(ifr.ifr_name));
357	ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0';
358	si.ic_cmd = NIOCBIND;
359	si.ic_len = sizeof(ifr);
360	si.ic_dp = (char *)&ifr;
361	if (ioctl(fd, I_STR, (char *)&si) < 0) {
362		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCBIND: %s: %s",
363			ifr.ifr_name, pcap_strerror(errno));
364		goto bad;
365	}
366
367	/* set the snapshot length */
368	si.ic_cmd = NIOCSSNAP;
369	si.ic_len = sizeof(p->snapshot);
370	si.ic_dp = (char *)&p->snapshot;
371	if (ioctl(fd, I_STR, (char *)&si) < 0) {
372		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "NIOCSSNAP: %s",
373		    pcap_strerror(errno));
374		goto bad;
375	}
376	if (nit_setflags(p) < 0)
377		goto bad;
378
379	(void)ioctl(fd, I_FLUSH, (char *)FLUSHR);
380	/*
381	 * NIT supports only ethernets.
382	 */
383	p->linktype = DLT_EN10MB;
384
385	p->bufsize = BUFSPACE;
386	p->buffer = (u_char *)malloc(p->bufsize);
387	if (p->buffer == NULL) {
388		strlcpy(p->errbuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
389		goto bad;
390	}
391
392	/*
393	 * "p->fd" is an FD for a STREAMS device, so "select()" and
394	 * "poll()" should work on it.
395	 */
396	p->selectable_fd = p->fd;
397
398	/*
399	 * This is (presumably) a real Ethernet capture; give it a
400	 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
401	 * that an application can let you choose it, in case you're
402	 * capturing DOCSIS traffic that a Cisco Cable Modem
403	 * Termination System is putting out onto an Ethernet (it
404	 * doesn't put an Ethernet header onto the wire, it puts raw
405	 * DOCSIS frames out on the wire inside the low-level
406	 * Ethernet framing).
407	 */
408	p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
409	/*
410	 * If that fails, just leave the list empty.
411	 */
412	if (p->dlt_list != NULL) {
413		p->dlt_list[0] = DLT_EN10MB;
414		p->dlt_list[1] = DLT_DOCSIS;
415		p->dlt_count = 2;
416	}
417
418	p->read_op = pcap_read_snit;
419	p->inject_op = pcap_inject_snit;
420	p->setfilter_op = install_bpf_program;	/* no kernel filtering */
421	p->setdirection_op = NULL;	/* Not implemented. */
422	p->set_datalink_op = NULL;	/* can't change data link type */
423	p->getnonblock_op = pcap_getnonblock_fd;
424	p->setnonblock_op = pcap_setnonblock_fd;
425	p->stats_op = pcap_stats_snit;
426
427	return (0);
428 bad:
429	pcap_cleanup_live_common(p);
430	return (PCAP_ERROR);
431}
432
433pcap_t *
434pcap_create_interface(const char *device, char *ebuf)
435{
436	pcap_t *p;
437
438	p = pcap_create_common(device, ebuf, sizeof (struct pcap_snit));
439	if (p == NULL)
440		return (NULL);
441
442	p->activate_op = pcap_activate_snit;
443	return (p);
444}
445
446int
447pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
448{
449	return (0);
450}
451