xref: /freebsd/contrib/libpcap/pcap-snf.c (revision afdbf109c6a661a729938f68211054a0a50d38ac)
1 #include <config.h>
2 
3 #ifndef _WIN32
4 #include <sys/param.h>
5 #endif /* !_WIN32 */
6 
7 #include <stdlib.h>
8 #include <string.h>
9 #include <errno.h>
10 #include <limits.h> /* for INT_MAX */
11 
12 #ifndef _WIN32
13 #include <netinet/in.h>
14 #include <sys/mman.h>
15 #include <sys/socket.h>
16 #include <sys/types.h>
17 #include <unistd.h>
18 #endif /* !_WIN32 */
19 
20 #include <snf.h>
21 #if SNF_VERSION_API >= 0x0003
22 #define SNF_HAVE_INJECT_API
23 #endif
24 
25 #include "pcap-int.h"
26 #include "pcap-snf.h"
27 
28 /*
29  * Private data for capturing on SNF devices.
30  */
31 struct pcap_snf {
32 	snf_handle_t snf_handle; /* opaque device handle */
33 	snf_ring_t   snf_ring;   /* opaque device ring handle */
34 #ifdef SNF_HAVE_INJECT_API
35 	snf_inject_t snf_inj;    /* inject handle, if inject is used */
36 #endif
37 	int          snf_timeout;
38 	int          snf_boardnum;
39 };
40 
41 static int
snf_set_datalink(pcap_t * p,int dlt)42 snf_set_datalink(pcap_t *p, int dlt)
43 {
44 	p->linktype = dlt;
45 	return (0);
46 }
47 
48 static int
snf_pcap_stats(pcap_t * p,struct pcap_stat * ps)49 snf_pcap_stats(pcap_t *p, struct pcap_stat *ps)
50 {
51 	struct snf_ring_stats stats;
52 	struct pcap_snf *snfps = p->priv;
53 	int rc;
54 
55 	if ((rc = snf_ring_getstats(snfps->snf_ring, &stats))) {
56 		pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
57 		    rc, "snf_get_stats");
58 		return -1;
59 	}
60 	ps->ps_recv = stats.ring_pkt_recv + stats.ring_pkt_overflow;
61 	ps->ps_drop = stats.ring_pkt_overflow;
62 	ps->ps_ifdrop = stats.nic_pkt_overflow + stats.nic_pkt_bad;
63 	return 0;
64 }
65 
66 static void
snf_platform_cleanup(pcap_t * p)67 snf_platform_cleanup(pcap_t *p)
68 {
69 	struct pcap_snf *ps = p->priv;
70 
71 #ifdef SNF_HAVE_INJECT_API
72 	if (ps->snf_inj)
73 		snf_inject_close(ps->snf_inj);
74 #endif
75 	snf_ring_close(ps->snf_ring);
76 	snf_close(ps->snf_handle);
77 	pcapint_cleanup_live_common(p);
78 }
79 
80 static int
snf_getnonblock(pcap_t * p)81 snf_getnonblock(pcap_t *p)
82 {
83 	struct pcap_snf *ps = p->priv;
84 
85 	return (ps->snf_timeout == 0);
86 }
87 
88 static int
snf_setnonblock(pcap_t * p,int nonblock)89 snf_setnonblock(pcap_t *p, int nonblock)
90 {
91 	struct pcap_snf *ps = p->priv;
92 
93 	if (nonblock)
94 		ps->snf_timeout = 0;
95 	else {
96 		if (p->opt.timeout <= 0)
97 			ps->snf_timeout = -1; /* forever */
98 		else
99 			ps->snf_timeout = p->opt.timeout;
100 	}
101 	return (0);
102 }
103 
104 #define _NSEC_PER_SEC 1000000000
105 
106 static inline
107 struct timeval
snf_timestamp_to_timeval(const int64_t ts_nanosec,const int tstamp_precision)108 snf_timestamp_to_timeval(const int64_t ts_nanosec, const int tstamp_precision)
109 {
110 	struct timeval tv;
111 	long tv_nsec;
112         const static struct timeval zero_timeval;
113 
114         if (ts_nanosec == 0)
115                 return zero_timeval;
116 
117 	tv.tv_sec = ts_nanosec / _NSEC_PER_SEC;
118 	tv_nsec = (ts_nanosec % _NSEC_PER_SEC);
119 
120 	/* libpcap expects tv_usec to be nanos if using nanosecond precision. */
121 	if (tstamp_precision == PCAP_TSTAMP_PRECISION_NANO)
122 		tv.tv_usec = tv_nsec;
123 	else
124 		tv.tv_usec = tv_nsec / 1000;
125 
126 	return tv;
127 }
128 
129 static int
snf_read(pcap_t * p,int cnt,pcap_handler callback,u_char * user)130 snf_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
131 {
132 	struct pcap_snf *ps = p->priv;
133 	struct pcap_pkthdr hdr;
134 	int i, flags, err, caplen, n;
135 	struct snf_recv_req req;
136 	int nonblock, timeout;
137 
138 	if (!p)
139 		return -1;
140 
141 	/*
142 	 * This can conceivably process more than INT_MAX packets,
143 	 * which would overflow the packet count, causing it either
144 	 * to look like a negative number, and thus cause us to
145 	 * return a value that looks like an error, or overflow
146 	 * back into positive territory, and thus cause us to
147 	 * return a too-low count.
148 	 *
149 	 * Therefore, if the packet count is unlimited, we clip
150 	 * it at INT_MAX; this routine is not expected to
151 	 * process packets indefinitely, so that's not an issue.
152 	 */
153 	if (PACKET_COUNT_IS_UNLIMITED(cnt))
154 		cnt = INT_MAX;
155 
156 	n = 0;
157 	timeout = ps->snf_timeout;
158 	while (n < cnt) {
159 		/*
160 		 * Has "pcap_breakloop()" been called?
161 		 */
162 		if (p->break_loop) {
163 			if (n == 0) {
164 				p->break_loop = 0;
165 				return (-2);
166 			} else {
167 				return (n);
168 			}
169 		}
170 
171 		err = snf_ring_recv(ps->snf_ring, timeout, &req);
172 
173 		if (err) {
174 			if (err == EBUSY || err == EAGAIN) {
175 				return (n);
176 			}
177 			else if (err == EINTR) {
178 				timeout = 0;
179 				continue;
180 			}
181 			else {
182 				pcapint_fmt_errmsg_for_errno(p->errbuf,
183 				    PCAP_ERRBUF_SIZE, err, "snf_read");
184 				return -1;
185 			}
186 		}
187 
188 		caplen = req.length;
189 		if (caplen > p->snapshot)
190 			caplen = p->snapshot;
191 
192 		if ((p->fcode.bf_insns == NULL) ||
193 		     pcapint_filter(p->fcode.bf_insns, req.pkt_addr, req.length, caplen)) {
194 			hdr.ts = snf_timestamp_to_timeval(req.timestamp, p->opt.tstamp_precision);
195 			hdr.caplen = caplen;
196 			hdr.len = req.length;
197 			callback(user, &hdr, req.pkt_addr);
198 			n++;
199 		}
200 
201 		/* After one successful packet is received, we won't block
202 		* again for that timeout. */
203 		if (timeout != 0)
204 			timeout = 0;
205 	}
206 	return (n);
207 }
208 
209 static int
snf_inject(pcap_t * p,const void * buf _U_,int size _U_)210 snf_inject(pcap_t *p, const void *buf _U_, int size _U_)
211 {
212 #ifdef SNF_HAVE_INJECT_API
213 	struct pcap_snf *ps = p->priv;
214 	int rc;
215 	if (ps->snf_inj == NULL) {
216 		rc = snf_inject_open(ps->snf_boardnum, 0, &ps->snf_inj);
217 		if (rc) {
218 			pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
219 			    rc, "snf_inject_open");
220 			return (-1);
221 		}
222 	}
223 
224 	rc = snf_inject_send(ps->snf_inj, -1, 0, buf, size);
225 	if (!rc) {
226 		return (size);
227 	}
228 	else {
229 		pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
230 		    rc, "snf_inject_send");
231 		return (-1);
232 	}
233 #else
234 	pcapint_strlcpy(p->errbuf, "Sending packets isn't supported with this snf version",
235 	    PCAP_ERRBUF_SIZE);
236 	return (-1);
237 #endif
238 }
239 
240 static int
snf_activate(pcap_t * p)241 snf_activate(pcap_t* p)
242 {
243 	struct pcap_snf *ps = p->priv;
244 	char *device = p->opt.device;
245 	const char *nr = NULL;
246 	int err;
247 	int flags = -1, ring_id = -1;
248 
249 	if (device == NULL) {
250 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "device is NULL");
251 		return -1;
252 	}
253 
254 	/* In Libpcap, we set pshared by default if NUM_RINGS is set to > 1.
255 	 * Since libpcap isn't thread-safe */
256 	if ((nr = getenv("SNF_FLAGS")) && *nr)
257 		flags = strtol(nr, NULL, 0);
258 	else if ((nr = getenv("SNF_NUM_RINGS")) && *nr && atoi(nr) > 1)
259 		flags = SNF_F_PSHARED;
260 	else
261 		nr = NULL;
262 
263 
264         /* Allow pcap_set_buffer_size() to set dataring_size.
265          * Default is zero which allows setting from env SNF_DATARING_SIZE.
266          * pcap_set_buffer_size() is in bytes while snf_open() accepts values
267          * between 0 and 1048576 in Megabytes. Values in this range are
268          * mapped to 1MB.
269          */
270 	err = snf_open(ps->snf_boardnum,
271 			0, /* let SNF API parse SNF_NUM_RINGS, if set */
272 			NULL, /* default RSS, or use SNF_RSS_FLAGS env */
273                         (p->opt.buffer_size > 0 && p->opt.buffer_size < 1048576) ? 1048576 : p->opt.buffer_size, /* default to SNF_DATARING_SIZE from env */
274 			flags, /* may want pshared */
275 			&ps->snf_handle);
276 	if (err != 0) {
277 		pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
278 		    err, "snf_open failed");
279 		return -1;
280 	}
281 
282 	if ((nr = getenv("SNF_PCAP_RING_ID")) && *nr) {
283 		ring_id = (int) strtol(nr, NULL, 0);
284 	}
285 	err = snf_ring_open_id(ps->snf_handle, ring_id, &ps->snf_ring);
286 	if (err != 0) {
287 		pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
288 		    err, "snf_ring_open_id(ring=%d) failed", ring_id);
289 		return -1;
290 	}
291 
292 	/*
293 	 * Turn a negative snapshot value (invalid), a snapshot value of
294 	 * 0 (unspecified), or a value bigger than the normal maximum
295 	 * value, into the maximum allowed value.
296 	 *
297 	 * If some application really *needs* a bigger snapshot
298 	 * length, we should just increase MAXIMUM_SNAPLEN.
299 	 */
300 	if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
301 		p->snapshot = MAXIMUM_SNAPLEN;
302 
303 	if (p->opt.timeout <= 0)
304 		ps->snf_timeout = -1;
305 	else
306 		ps->snf_timeout = p->opt.timeout;
307 
308 	err = snf_start(ps->snf_handle);
309 	if (err != 0) {
310 		pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
311 		    err, "snf_start failed");
312 		return -1;
313 	}
314 
315 	/*
316 	 * "select()" and "poll()" don't work on snf descriptors.
317 	 */
318 #ifndef _WIN32
319 	p->selectable_fd = -1;
320 #endif /* !_WIN32 */
321 	p->linktype = DLT_EN10MB;
322 	p->read_op = snf_read;
323 	p->inject_op = snf_inject;
324 	p->setfilter_op = pcapint_install_bpf_program;
325 	p->setdirection_op = NULL; /* Not implemented.*/
326 	p->set_datalink_op = snf_set_datalink;
327 	p->getnonblock_op = snf_getnonblock;
328 	p->setnonblock_op = snf_setnonblock;
329 	p->stats_op = snf_pcap_stats;
330 	p->cleanup_op = snf_platform_cleanup;
331 #ifdef SNF_HAVE_INJECT_API
332 	ps->snf_inj = NULL;
333 #endif
334 	return 0;
335 }
336 
337 #define MAX_DESC_LENGTH 128
338 int
snf_findalldevs(pcap_if_list_t * devlistp,char * errbuf)339 snf_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
340 {
341 	pcap_if_t *dev;
342 #ifdef _WIN32
343 	struct sockaddr_in addr;
344 #endif
345 	struct snf_ifaddrs *ifaddrs, *ifa;
346 	char name[MAX_DESC_LENGTH];
347 	char desc[MAX_DESC_LENGTH];
348 	int ret, allports = 0, merge = 0;
349 	const char *nr = NULL;
350 
351 	if (snf_init(SNF_VERSION_API)) {
352 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
353 		    "snf_getifaddrs: snf_init failed");
354 		return (-1);
355 	}
356 
357 	if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL)
358 	{
359 		pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
360 		    errno, "snf_getifaddrs");
361 		return (-1);
362 	}
363 	if ((nr = getenv("SNF_FLAGS")) && *nr) {
364 		errno = 0;
365 		merge = strtol(nr, NULL, 0);
366 		if (errno) {
367 			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
368 				"snf_getifaddrs: SNF_FLAGS is not a valid number");
369 			return (-1);
370 		}
371 		merge = merge & SNF_F_AGGREGATE_PORTMASK;
372 	}
373 
374 	for (ifa = ifaddrs; ifa != NULL; ifa = ifa->snf_ifa_next) {
375 		/*
376 		 * Myricom SNF adapter ports may appear as regular
377 		 * network interfaces, which would already have been
378 		 * added to the list of adapters by pcapint_platform_finddevs()
379 		 * if this isn't an SNF-only version of libpcap.
380 		 *
381 		 * Our create routine intercepts pcap_create() calls for
382 		 * those interfaces and arranges that they will be
383 		 * opened using the SNF API instead.
384 		 *
385 		 * So if we already have an entry for the device, we
386 		 * don't add an additional entry for it, we just
387 		 * update the description for it, if any, to indicate
388 		 * which snfN device it is.  Otherwise, we add an entry
389 		 * for it.
390 		 *
391 		 * In either case, if SNF_F_AGGREGATE_PORTMASK is set
392 		 * in SNF_FLAGS, we add this port to the bitmask
393 		 * of ports, which we use to generate a device
394 		 * we can use to capture on all ports.
395 		 *
396 		 * Generate the description string.  If port aggregation
397 		 * is set, use 2^{port number} as the unit number,
398 		 * rather than {port number}.
399 		 *
400 		 * XXX - do entries in this list have IP addresses for
401 		 * the port?  If so, should we add them to the
402 		 * entry for the device, if they're not already in the
403 		 * list of IP addresses for the device?
404 		 */
405 		(void)snprintf(desc,MAX_DESC_LENGTH,"Myricom %ssnf%d",
406 			merge ? "Merge Bitmask Port " : "",
407 			merge ? 1 << ifa->snf_ifa_portnum : ifa->snf_ifa_portnum);
408 		/*
409 		 * Add the port to the bitmask.
410 		 */
411 		if (merge)
412 			allports |= 1 << ifa->snf_ifa_portnum;
413 		/*
414 		 * See if there's already an entry for the device
415 		 * with the name ifa->snf_ifa_name.
416 		 */
417 		dev = pcapint_find_dev(devlistp, ifa->snf_ifa_name);
418 		if (dev != NULL) {
419 			/*
420 			 * Yes.  Update its description.
421 			 */
422 			char *desc_str;
423 
424 			desc_str = strdup(desc);
425 			if (desc_str == NULL) {
426 				pcapint_fmt_errmsg_for_errno(errbuf,
427 				    PCAP_ERRBUF_SIZE, errno,
428 				    "snf_findalldevs strdup");
429 				return -1;
430 			}
431 			free(dev->description);
432 			dev->description = desc_str;
433 		} else {
434 			/*
435 			 * No.  Add an entry for it.
436 			 *
437 			 * XXX - is there a notion of "up" or "running",
438 			 * and can we determine whether something's
439 			 * plugged into the adapter and set
440 			 * PCAP_IF_CONNECTION_STATUS_CONNECTED or
441 			 * PCAP_IF_CONNECTION_STATUS_DISCONNECTED?
442 			 */
443 			dev = pcapint_add_dev(devlistp, ifa->snf_ifa_name, 0, desc,
444 			    errbuf);
445 			if (dev == NULL)
446 				return -1;
447 #ifdef _WIN32
448 			/*
449 			 * On Windows, fill in IP# from device name
450 			 */
451                         ret = inet_pton(AF_INET, dev->name, &addr.sin_addr);
452                         if (ret == 1) {
453 				/*
454 				 * Successful conversion of device name
455 				 * to IPv4 address.
456 				 */
457 				addr.sin_family = AF_INET;
458 				if (pcapint_add_addr_to_dev(dev, &addr, sizeof(addr),
459 				    NULL, 0, NULL, 0, NULL, 0, errbuf) == -1)
460 					return -1;
461                         } else if (ret == -1) {
462 				/*
463 				 * Error.
464 				 */
465 				pcapint_fmt_errmsg_for_errno(errbuf,
466 				    PCAP_ERRBUF_SIZE, errno,
467 				    "sinf_findalldevs inet_pton");
468                                 return -1;
469                         }
470 #endif _WIN32
471 		}
472 	}
473 	snf_freeifaddrs(ifaddrs);
474 	/*
475 	 * Create a snfX entry if port aggregation is enabled
476 	 */
477 	if (merge) {
478 		/*
479 		 * Add a new entry with all ports bitmask
480 		 */
481 		(void)snprintf(name,MAX_DESC_LENGTH,"snf%d",allports);
482 		(void)snprintf(desc,MAX_DESC_LENGTH,"Myricom Merge Bitmask All Ports snf%d",
483 			allports);
484 		/*
485 		 * XXX - is there any notion of "up" and "running" that
486 		 * would apply to this device, given that it handles
487 		 * multiple ports?
488 		 *
489 		 * Presumably, there's no notion of "connected" vs.
490 		 * "disconnected", as "is this plugged into a network?"
491 		 * would be a per-port property.
492 		 */
493 		if (pcapint_add_dev(devlistp, name,
494 		    PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE, desc,
495 		    errbuf) == NULL)
496 			return (-1);
497 		/*
498 		 * XXX - should we give it a list of addresses with all
499 		 * the addresses for all the ports?
500 		 */
501 	}
502 
503 	return 0;
504 }
505 
506 pcap_t *
snf_create(const char * device,char * ebuf,int * is_ours)507 snf_create(const char *device, char *ebuf, int *is_ours)
508 {
509 	pcap_t *p;
510 	int boardnum = -1;
511 	struct snf_ifaddrs *ifaddrs, *ifa;
512 	size_t devlen;
513 	struct pcap_snf *ps;
514 
515 	if (snf_init(SNF_VERSION_API)) {
516 		/* Can't initialize the API, so no SNF devices */
517 		*is_ours = 0;
518 		return NULL;
519 	}
520 
521 	/*
522 	 * Match a given interface name to our list of interface names, from
523 	 * which we can obtain the intended board number
524 	 */
525 	if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL) {
526 		/* Can't get SNF addresses */
527 		*is_ours = 0;
528 		return NULL;
529 	}
530 	devlen = strlen(device) + 1;
531 	ifa = ifaddrs;
532 	while (ifa) {
533 		if (strncmp(device, ifa->snf_ifa_name, devlen) == 0) {
534 			boardnum = ifa->snf_ifa_boardnum;
535 			break;
536 		}
537 		ifa = ifa->snf_ifa_next;
538 	}
539 	snf_freeifaddrs(ifaddrs);
540 
541 	if (ifa == NULL) {
542 		/*
543 		 * If we can't find the device by name, support the name "snfX"
544 		 * and "snf10gX" where X is the board number.
545 		 */
546 		if (sscanf(device, "snf10g%d", &boardnum) != 1 &&
547 		    sscanf(device, "snf%d", &boardnum) != 1) {
548 			/* Nope, not a supported name */
549 			*is_ours = 0;
550 			return NULL;
551 		}
552 	}
553 
554 	/* OK, it's probably ours. */
555 	*is_ours = 1;
556 
557 	p = PCAP_CREATE_COMMON(ebuf, struct pcap_snf);
558 	if (p == NULL)
559 		return NULL;
560 	ps = p->priv;
561 
562 	/*
563 	 * We support microsecond and nanosecond time stamps.
564 	 */
565 	p->tstamp_precision_list = malloc(2 * sizeof(u_int));
566 	if (p->tstamp_precision_list == NULL) {
567 		pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE, errno,
568 		    "malloc");
569 		pcap_close(p);
570 		return NULL;
571 	}
572 	p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
573 	p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
574 	p->tstamp_precision_count = 2;
575 
576 	p->activate_op = snf_activate;
577 	ps->snf_boardnum = boardnum;
578 	return p;
579 }
580 
581 #ifdef SNF_ONLY
582 /*
583  * This libpcap build supports only SNF cards, not regular network
584  * interfaces..
585  */
586 
587 /*
588  * There are no regular interfaces, just SNF interfaces.
589  */
590 int
pcapint_platform_finddevs(pcap_if_list_t * devlistp,char * errbuf)591 pcapint_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
592 {
593 	return (0);
594 }
595 
596 /*
597  * Attempts to open a regular interface fail.
598  */
599 pcap_t *
pcapint_create_interface(const char * device,char * errbuf)600 pcapint_create_interface(const char *device, char *errbuf)
601 {
602 	snprintf(errbuf, PCAP_ERRBUF_SIZE,
603 	    "This version of libpcap only supports SNF cards");
604 	return NULL;
605 }
606 
607 /*
608  * Libpcap version string.
609  */
610 const char *
pcap_lib_version(void)611 pcap_lib_version(void)
612 {
613 	return (PCAP_VERSION_STRING " (SNF-only)");
614 }
615 #endif
616