xref: /freebsd/contrib/libpcap/pcap-libdlpi.c (revision a7dea1671b87c07d2d266f836bfa8b58efc7c134)
1 /*
2  * Copyright (c) 1993, 1994, 1995, 1996, 1997
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  * This code contributed by Sagun Shakya (sagun.shakya@sun.com)
22  */
23 /*
24  * Packet capture routines for DLPI using libdlpi under SunOS 5.11.
25  */
26 
27 #ifdef HAVE_CONFIG_H
28 #include <config.h>
29 #endif
30 
31 #include <sys/types.h>
32 #include <sys/time.h>
33 #include <sys/bufmod.h>
34 #include <sys/stream.h>
35 #include <libdlpi.h>
36 #include <errno.h>
37 #include <memory.h>
38 #include <stropts.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 #include "pcap-int.h"
44 #include "dlpisubs.h"
45 
46 /* Forwards. */
47 static int dlpromiscon(pcap_t *, bpf_u_int32);
48 static int pcap_read_libdlpi(pcap_t *, int, pcap_handler, u_char *);
49 static int pcap_inject_libdlpi(pcap_t *, const void *, size_t);
50 static void pcap_libdlpi_err(const char *, const char *, int, char *);
51 static void pcap_cleanup_libdlpi(pcap_t *);
52 
53 /*
54  * list_interfaces() will list all the network links that are
55  * available on a system.
56  */
57 static boolean_t list_interfaces(const char *, void *);
58 
59 typedef struct linknamelist {
60 	char	linkname[DLPI_LINKNAME_MAX];
61 	struct linknamelist *lnl_next;
62 } linknamelist_t;
63 
64 typedef struct linkwalk {
65 	linknamelist_t	*lw_list;
66 	int		lw_err;
67 } linkwalk_t;
68 
69 /*
70  * The caller of this function should free the memory allocated
71  * for each linknamelist_t "entry" allocated.
72  */
73 static boolean_t
74 list_interfaces(const char *linkname, void *arg)
75 {
76 	linkwalk_t	*lwp = arg;
77 	linknamelist_t	*entry;
78 
79 	if ((entry = calloc(1, sizeof(linknamelist_t))) == NULL) {
80 		lwp->lw_err = ENOMEM;
81 		return (B_TRUE);
82 	}
83 	(void) pcap_strlcpy(entry->linkname, linkname, DLPI_LINKNAME_MAX);
84 
85 	if (lwp->lw_list == NULL) {
86 		lwp->lw_list = entry;
87 	} else {
88 		entry->lnl_next = lwp->lw_list;
89 		lwp->lw_list = entry;
90 	}
91 
92 	return (B_FALSE);
93 }
94 
95 static int
96 pcap_activate_libdlpi(pcap_t *p)
97 {
98 	struct pcap_dlpi *pd = p->priv;
99 	int status = 0;
100 	int retv;
101 	dlpi_handle_t dh;
102 	dlpi_info_t dlinfo;
103 
104 	/*
105 	 * Enable Solaris raw and passive DLPI extensions;
106 	 * dlpi_open() will not fail if the underlying link does not support
107 	 * passive mode. See dlpi(7P) for details.
108 	 */
109 	retv = dlpi_open(p->opt.device, &dh, DLPI_RAW|DLPI_PASSIVE);
110 	if (retv != DLPI_SUCCESS) {
111 		if (retv == DLPI_ELINKNAMEINVAL || retv == DLPI_ENOLINK)
112 			status = PCAP_ERROR_NO_SUCH_DEVICE;
113 		else if (retv == DL_SYSERR &&
114 		    (errno == EPERM || errno == EACCES))
115 			status = PCAP_ERROR_PERM_DENIED;
116 		else
117 			status = PCAP_ERROR;
118 		pcap_libdlpi_err(p->opt.device, "dlpi_open", retv,
119 		    p->errbuf);
120 		return (status);
121 	}
122 	pd->dlpi_hd = dh;
123 
124 	if (p->opt.rfmon) {
125 		/*
126 		 * This device exists, but we don't support monitor mode
127 		 * any platforms that support DLPI.
128 		 */
129 		status = PCAP_ERROR_RFMON_NOTSUP;
130 		goto bad;
131 	}
132 
133 	/* Bind with DLPI_ANY_SAP. */
134 	if ((retv = dlpi_bind(pd->dlpi_hd, DLPI_ANY_SAP, 0)) != DLPI_SUCCESS) {
135 		status = PCAP_ERROR;
136 		pcap_libdlpi_err(p->opt.device, "dlpi_bind", retv, p->errbuf);
137 		goto bad;
138 	}
139 
140 	/*
141 	 * Turn a negative snapshot value (invalid), a snapshot value of
142 	 * 0 (unspecified), or a value bigger than the normal maximum
143 	 * value, into the maximum allowed value.
144 	 *
145 	 * If some application really *needs* a bigger snapshot
146 	 * length, we should just increase MAXIMUM_SNAPLEN.
147 	 */
148 	if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
149 		p->snapshot = MAXIMUM_SNAPLEN;
150 
151 	/* Enable promiscuous mode. */
152 	if (p->opt.promisc) {
153 		retv = dlpromiscon(p, DL_PROMISC_PHYS);
154 		if (retv < 0) {
155 			/*
156 			 * "You don't have permission to capture on
157 			 * this device" and "you don't have permission
158 			 * to capture in promiscuous mode on this
159 			 * device" are different; let the user know,
160 			 * so if they can't get permission to
161 			 * capture in promiscuous mode, they can at
162 			 * least try to capture in non-promiscuous
163 			 * mode.
164 			 *
165 			 * XXX - you might have to capture in
166 			 * promiscuous mode to see outgoing packets.
167 			 */
168 			if (retv == PCAP_ERROR_PERM_DENIED)
169 				status = PCAP_ERROR_PROMISC_PERM_DENIED;
170 			else
171 				status = retv;
172 			goto bad;
173 		}
174 	} else {
175 		/* Try to enable multicast. */
176 		retv = dlpromiscon(p, DL_PROMISC_MULTI);
177 		if (retv < 0) {
178 			status = retv;
179 			goto bad;
180 		}
181 	}
182 
183 	/* Try to enable SAP promiscuity. */
184 	retv = dlpromiscon(p, DL_PROMISC_SAP);
185 	if (retv < 0) {
186 		/*
187 		 * Not fatal, since the DL_PROMISC_PHYS mode worked.
188 		 * Report it as a warning, however.
189 		 */
190 		if (p->opt.promisc)
191 			status = PCAP_WARNING;
192 		else {
193 			status = retv;
194 			goto bad;
195 		}
196 	}
197 
198 	/* Determine link type.  */
199 	if ((retv = dlpi_info(pd->dlpi_hd, &dlinfo, 0)) != DLPI_SUCCESS) {
200 		status = PCAP_ERROR;
201 		pcap_libdlpi_err(p->opt.device, "dlpi_info", retv, p->errbuf);
202 		goto bad;
203 	}
204 
205 	if (pcap_process_mactype(p, dlinfo.di_mactype) != 0) {
206 		status = PCAP_ERROR;
207 		goto bad;
208 	}
209 
210 	p->fd = dlpi_fd(pd->dlpi_hd);
211 
212 	/* Push and configure bufmod. */
213 	if (pcap_conf_bufmod(p, p->snapshot) != 0) {
214 		status = PCAP_ERROR;
215 		goto bad;
216 	}
217 
218 	/*
219 	 * Flush the read side.
220 	 */
221 	if (ioctl(p->fd, I_FLUSH, FLUSHR) != 0) {
222 		status = PCAP_ERROR;
223 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
224 		    errno, "FLUSHR");
225 		goto bad;
226 	}
227 
228 	/* Allocate data buffer. */
229 	if (pcap_alloc_databuf(p) != 0) {
230 		status = PCAP_ERROR;
231 		goto bad;
232 	}
233 
234 	/*
235 	 * "p->fd" is a FD for a STREAMS device, so "select()" and
236 	 * "poll()" should work on it.
237 	 */
238 	p->selectable_fd = p->fd;
239 
240 	p->read_op = pcap_read_libdlpi;
241 	p->inject_op = pcap_inject_libdlpi;
242 	p->setfilter_op = install_bpf_program;	/* No kernel filtering */
243 	p->setdirection_op = NULL;	/* Not implemented */
244 	p->set_datalink_op = NULL;	/* Can't change data link type */
245 	p->getnonblock_op = pcap_getnonblock_fd;
246 	p->setnonblock_op = pcap_setnonblock_fd;
247 	p->stats_op = pcap_stats_dlpi;
248 	p->cleanup_op = pcap_cleanup_libdlpi;
249 
250 	return (status);
251 bad:
252 	pcap_cleanup_libdlpi(p);
253 	return (status);
254 }
255 
256 #define STRINGIFY(n)	#n
257 
258 static int
259 dlpromiscon(pcap_t *p, bpf_u_int32 level)
260 {
261 	struct pcap_dlpi *pd = p->priv;
262 	int retv;
263 	int err;
264 
265 	retv = dlpi_promiscon(pd->dlpi_hd, level);
266 	if (retv != DLPI_SUCCESS) {
267 		if (retv == DL_SYSERR &&
268 		    (errno == EPERM || errno == EACCES))
269 			err = PCAP_ERROR_PERM_DENIED;
270 		else
271 			err = PCAP_ERROR;
272 		pcap_libdlpi_err(p->opt.device, "dlpi_promiscon" STRINGIFY(level),
273 		    retv, p->errbuf);
274 		return (err);
275 	}
276 	return (0);
277 }
278 
279 /*
280  * Presumably everything returned by dlpi_walk() is a DLPI device,
281  * so there's no work to be done here to check whether name refers
282  * to a DLPI device.
283  */
284 static int
285 is_dlpi_interface(const char *name _U_)
286 {
287 	return (1);
288 }
289 
290 static int
291 get_if_flags(const char *name _U_, bpf_u_int32 *flags _U_, char *errbuf _U_)
292 {
293 	/*
294 	 * Nothing we can do other than mark loopback devices as "the
295 	 * connected/disconnected status doesn't apply".
296 	 *
297 	 * XXX - on Solaris, can we do what the dladm command does,
298 	 * i.e. get a connected/disconnected indication from a kstat?
299 	 * (Note that you can also get the link speed, and possibly
300 	 * other information, from a kstat as well.)
301 	 */
302 	if (*flags & PCAP_IF_LOOPBACK) {
303 		/*
304 		 * Loopback devices aren't wireless, and "connected"/
305 		 * "disconnected" doesn't apply to them.
306 		 */
307 		*flags |= PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE;
308 		return (0);
309 	}
310 	return (0);
311 }
312 
313 /*
314  * In Solaris, the "standard" mechanism" i.e SIOCGLIFCONF will only find
315  * network links that are plumbed and are up. dlpi_walk(3DLPI) will find
316  * additional network links present in the system.
317  */
318 int
319 pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
320 {
321 	int retv = 0;
322 
323 	linknamelist_t	*entry, *next;
324 	linkwalk_t	lw = {NULL, 0};
325 	int 		save_errno;
326 
327 	/*
328 	 * Get the list of regular interfaces first.
329 	 */
330 	if (pcap_findalldevs_interfaces(devlistp, errbuf,
331 	    is_dlpi_interface, get_if_flags) == -1)
332 		return (-1);	/* failure */
333 
334 	/* dlpi_walk() for loopback will be added here. */
335 
336 	/*
337 	 * Find all DLPI devices in the current zone.
338 	 *
339 	 * XXX - will pcap_findalldevs_interfaces() find any devices
340 	 * outside the current zone?  If not, the only reason to call
341 	 * it would be to get the interface addresses.
342 	 */
343 	dlpi_walk(list_interfaces, &lw, 0);
344 
345 	if (lw.lw_err != 0) {
346 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
347 		    lw.lw_err, "dlpi_walk");
348 		retv = -1;
349 		goto done;
350 	}
351 
352 	/* Add linkname if it does not exist on the list. */
353 	for (entry = lw.lw_list; entry != NULL; entry = entry->lnl_next) {
354 		/*
355 		 * If it isn't already in the list of devices, try to
356 		 * add it.
357 		 */
358 		if (find_or_add_dev(devlistp, entry->linkname, 0, get_if_flags,
359 		    NULL, errbuf) == NULL)
360 			retv = -1;
361 	}
362 done:
363 	save_errno = errno;
364 	for (entry = lw.lw_list; entry != NULL; entry = next) {
365 		next = entry->lnl_next;
366 		free(entry);
367 	}
368 	errno = save_errno;
369 
370 	return (retv);
371 }
372 
373 /*
374  * Read data received on DLPI handle. Returns -2 if told to terminate, else
375  * returns the number of packets read.
376  */
377 static int
378 pcap_read_libdlpi(pcap_t *p, int count, pcap_handler callback, u_char *user)
379 {
380 	struct pcap_dlpi *pd = p->priv;
381 	int len;
382 	u_char *bufp;
383 	size_t msglen;
384 	int retv;
385 
386 	len = p->cc;
387 	if (len != 0) {
388 		bufp = p->bp;
389 		goto process_pkts;
390 	}
391 	do {
392 		/* Has "pcap_breakloop()" been called? */
393 		if (p->break_loop) {
394 			/*
395 			 * Yes - clear the flag that indicates that it has,
396 			 * and return -2 to indicate that we were told to
397 			 * break out of the loop.
398 			 */
399 			p->break_loop = 0;
400 			return (-2);
401 		}
402 
403 		msglen = p->bufsize;
404 		bufp = (u_char *)p->buffer + p->offset;
405 
406 		retv = dlpi_recv(pd->dlpi_hd, NULL, NULL, bufp,
407 		    &msglen, -1, NULL);
408 		if (retv != DLPI_SUCCESS) {
409 			/*
410 			 * This is most likely a call to terminate out of the
411 			 * loop. So, do not return an error message, instead
412 			 * check if "pcap_breakloop()" has been called above.
413 			 */
414 			if (retv == DL_SYSERR && errno == EINTR) {
415 				len = 0;
416 				continue;
417 			}
418 			pcap_libdlpi_err(dlpi_linkname(pd->dlpi_hd),
419 			    "dlpi_recv", retv, p->errbuf);
420 			return (-1);
421 		}
422 		len = msglen;
423 	} while (len == 0);
424 
425 process_pkts:
426 	return (pcap_process_pkts(p, callback, user, count, bufp, len));
427 }
428 
429 static int
430 pcap_inject_libdlpi(pcap_t *p, const void *buf, size_t size)
431 {
432 	struct pcap_dlpi *pd = p->priv;
433 	int retv;
434 
435 	retv = dlpi_send(pd->dlpi_hd, NULL, 0, buf, size, NULL);
436 	if (retv != DLPI_SUCCESS) {
437 		pcap_libdlpi_err(dlpi_linkname(pd->dlpi_hd), "dlpi_send", retv,
438 		    p->errbuf);
439 		return (-1);
440 	}
441 	/*
442 	 * dlpi_send(3DLPI) does not provide a way to return the number of
443 	 * bytes sent on the wire. Based on the fact that DLPI_SUCCESS was
444 	 * returned we are assuming 'size' bytes were sent.
445 	 */
446 	return (size);
447 }
448 
449 /*
450  * Close dlpi handle.
451  */
452 static void
453 pcap_cleanup_libdlpi(pcap_t *p)
454 {
455 	struct pcap_dlpi *pd = p->priv;
456 
457 	if (pd->dlpi_hd != NULL) {
458 		dlpi_close(pd->dlpi_hd);
459 		pd->dlpi_hd = NULL;
460 		p->fd = -1;
461 	}
462 	pcap_cleanup_live_common(p);
463 }
464 
465 /*
466  * Write error message to buffer.
467  */
468 static void
469 pcap_libdlpi_err(const char *linkname, const char *func, int err, char *errbuf)
470 {
471 	pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "libpcap: %s failed on %s: %s",
472 	    func, linkname, dlpi_strerror(err));
473 }
474 
475 pcap_t *
476 pcap_create_interface(const char *device _U_, char *ebuf)
477 {
478 	pcap_t *p;
479 
480 	p = pcap_create_common(ebuf, sizeof (struct pcap_dlpi));
481 	if (p == NULL)
482 		return (NULL);
483 
484 	p->activate_op = pcap_activate_libdlpi;
485 	return (p);
486 }
487 
488 /*
489  * Libpcap version string.
490  */
491 const char *
492 pcap_lib_version(void)
493 {
494 	return (PCAP_VERSION_STRING);
495 }
496