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