xref: /netbsd-src/external/bsd/libpcap/dist/pcap-snf.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 #include <sys/cdefs.h>
2 __RCSID("$NetBSD: pcap-snf.c,v 1.4 2017/01/24 22:29:28 christos Exp $");
3 
4 /*	$NetBSD: pcap-snf.c,v 1.4 2017/01/24 22:29:28 christos Exp $	*/
5 
6 #ifdef HAVE_CONFIG_H
7 #include "config.h"
8 #endif
9 
10 #include <sys/param.h>
11 
12 #include <stdlib.h>
13 #include <string.h>
14 #include <errno.h>
15 
16 #include <ctype.h>
17 #include <netinet/in.h>
18 #include <sys/mman.h>
19 #include <sys/socket.h>
20 #include <sys/types.h>
21 #include <unistd.h>
22 
23 #include <snf.h>
24 #if SNF_VERSION_API >= 0x0003
25 #define SNF_HAVE_INJECT_API
26 #endif
27 
28 #include "pcap-int.h"
29 #include "pcap-snf.h"
30 
31 /*
32  * Private data for capturing on SNF devices.
33  */
34 struct pcap_snf {
35 	snf_handle_t snf_handle; /* opaque device handle */
36 	snf_ring_t   snf_ring;   /* opaque device ring handle */
37 #ifdef SNF_HAVE_INJECT_API
38         snf_inject_t snf_inj;    /* inject handle, if inject is used */
39 #endif
40         int          snf_timeout;
41         int          snf_boardnum;
42 };
43 
44 static int
45 snf_set_datalink(pcap_t *p, int dlt)
46 {
47 	p->linktype = dlt;
48 	return (0);
49 }
50 
51 static int
52 snf_pcap_stats(pcap_t *p, struct pcap_stat *ps)
53 {
54 	struct snf_ring_stats stats;
55 	struct pcap_snf *snfps = p->priv;
56 	int rc;
57 
58 	if ((rc = snf_ring_getstats(snfps->snf_ring, &stats))) {
59 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_get_stats: %s",
60 			 pcap_strerror(rc));
61 		return -1;
62 	}
63 	ps->ps_recv = stats.ring_pkt_recv + stats.ring_pkt_overflow;
64 	ps->ps_drop = stats.ring_pkt_overflow;
65 	ps->ps_ifdrop = stats.nic_pkt_overflow + stats.nic_pkt_bad;
66 	return 0;
67 }
68 
69 static void
70 snf_platform_cleanup(pcap_t *p)
71 {
72 	struct pcap_snf *ps = p->priv;
73 
74 #ifdef SNF_HAVE_INJECT_API
75         if (ps->snf_inj)
76                 snf_inject_close(ps->snf_inj);
77 #endif
78 	snf_ring_close(ps->snf_ring);
79 	snf_close(ps->snf_handle);
80 	pcap_cleanup_live_common(p);
81 }
82 
83 static int
84 snf_getnonblock(pcap_t *p, char *errbuf)
85 {
86 	struct pcap_snf *ps = p->priv;
87 
88 	return (ps->snf_timeout == 0);
89 }
90 
91 static int
92 snf_setnonblock(pcap_t *p, int nonblock, char *errbuf)
93 {
94 	struct pcap_snf *ps = p->priv;
95 
96 	if (nonblock)
97 		ps->snf_timeout = 0;
98 	else {
99 		if (p->opt.timeout <= 0)
100 			ps->snf_timeout = -1; /* forever */
101 		else
102 			ps->snf_timeout = p->opt.timeout;
103 	}
104 	return (0);
105 }
106 
107 #define _NSEC_PER_SEC 1000000000
108 
109 static inline
110 struct timeval
111 snf_timestamp_to_timeval(const int64_t ts_nanosec, const int tstamp_precision)
112 {
113 	struct timeval tv;
114 	long tv_nsec;
115 
116 	if (ts_nanosec == 0)
117 		return (struct timeval) { 0, 0 };
118 
119 	tv.tv_sec = ts_nanosec / _NSEC_PER_SEC;
120 	tv_nsec = (ts_nanosec % _NSEC_PER_SEC);
121 
122 	/* libpcap expects tv_usec to be nanos if using nanosecond precision. */
123 	if (tstamp_precision == PCAP_TSTAMP_PRECISION_NANO)
124 		tv.tv_usec = tv_nsec;
125 	else
126 		tv.tv_usec = tv_nsec / 1000;
127 
128 	return tv;
129 }
130 
131 static int
132 snf_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
133 {
134 	struct pcap_snf *ps = p->priv;
135 	struct pcap_pkthdr hdr;
136 	int i, flags, err, caplen, n;
137 	struct snf_recv_req req;
138 	int nonblock, timeout;
139 
140 	if (!p)
141 		return -1;
142 
143 	n = 0;
144 	timeout = ps->snf_timeout;
145 	while (n < cnt || PACKET_COUNT_IS_UNLIMITED(cnt)) {
146 		/*
147 		 * Has "pcap_breakloop()" been called?
148 		 */
149 		if (p->break_loop) {
150 			if (n == 0) {
151 				p->break_loop = 0;
152 				return (-2);
153 			} else {
154 				return (n);
155 			}
156 		}
157 
158 		err = snf_ring_recv(ps->snf_ring, timeout, &req);
159 
160 		if (err) {
161 			if (err == EBUSY || err == EAGAIN) {
162 				return (n);
163 			}
164 			else if (err == EINTR) {
165 				timeout = 0;
166 				continue;
167 			}
168 			else {
169 				pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_read: %s",
170 				 	 pcap_strerror(err));
171 				return -1;
172 			}
173 		}
174 
175 		caplen = req.length;
176 		if (caplen > p->snapshot)
177 			caplen = p->snapshot;
178 
179 		if ((p->fcode.bf_insns == NULL) ||
180 		     bpf_filter(p->fcode.bf_insns, req.pkt_addr, req.length, caplen)) {
181 			hdr.ts = snf_timestamp_to_timeval(req.timestamp, p->opt.tstamp_precision);
182 			hdr.caplen = caplen;
183 			hdr.len = req.length;
184 			callback(user, &hdr, req.pkt_addr);
185 		}
186 		n++;
187 
188 		/* After one successful packet is received, we won't block
189 		* again for that timeout. */
190 		if (timeout != 0)
191 			timeout = 0;
192 	}
193 	return (n);
194 }
195 
196 static int
197 snf_setfilter(pcap_t *p, struct bpf_program *fp)
198 {
199 	if (!p)
200 		return -1;
201 	if (!fp) {
202 		strncpy(p->errbuf, "setfilter: No filter specified",
203 			sizeof(p->errbuf));
204 		return -1;
205 	}
206 
207 	/* Make our private copy of the filter */
208 
209 	if (install_bpf_program(p, fp) < 0)
210 		return -1;
211 
212 	return (0);
213 }
214 
215 static int
216 snf_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
217 {
218 #ifdef SNF_HAVE_INJECT_API
219 	struct pcap_snf *ps = p->priv;
220         int rc;
221         if (ps->snf_inj == NULL) {
222                 rc = snf_inject_open(ps->snf_boardnum, 0, &ps->snf_inj);
223                 if (rc) {
224                         pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
225                                 "snf_inject_open: %s", pcap_strerror(rc));
226                         return (-1);
227                 }
228         }
229 
230         rc = snf_inject_send(ps->snf_inj, -1, 0, buf, size);
231         if (!rc) {
232                 return (size);
233         }
234         else {
235                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_inject_send: %s",
236                          pcap_strerror(rc));
237                 return (-1);
238         }
239 #else
240 	strlcpy(p->errbuf, "Sending packets isn't supported with this snf version",
241 	    PCAP_ERRBUF_SIZE);
242 	return (-1);
243 #endif
244 }
245 
246 static int
247 snf_activate(pcap_t* p)
248 {
249 	struct pcap_snf *ps = p->priv;
250 	char *device = p->opt.device;
251 	const char *nr = NULL;
252 	int err;
253 	int flags = -1, ring_id = -1;
254 
255 	if (device == NULL) {
256 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
257 			 "device is NULL: %s", pcap_strerror(errno));
258 		return -1;
259 	}
260 
261 	/* In Libpcap, we set pshared by default if NUM_RINGS is set to > 1.
262 	 * Since libpcap isn't thread-safe */
263 	if ((nr = getenv("SNF_FLAGS")) && *nr)
264 		flags = strtol(nr, NULL, 0);
265 	else if ((nr = getenv("SNF_NUM_RINGS")) && *nr && atoi(nr) > 1)
266 		flags = SNF_F_PSHARED;
267 	else
268 		nr = NULL;
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 			0, /* default to SNF_DATARING_SIZE from env */
274 			flags, /* may want pshared */
275 			&ps->snf_handle);
276 	if (err != 0) {
277 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
278 			 "snf_open failed: %s", pcap_strerror(err));
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 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
288 			 "snf_ring_open_id(ring=%d) failed: %s",
289 			 ring_id, pcap_strerror(err));
290 		return -1;
291 	}
292 
293 	if (p->opt.timeout <= 0)
294 		ps->snf_timeout = -1;
295 	else
296 		ps->snf_timeout = p->opt.timeout;
297 
298 	err = snf_start(ps->snf_handle);
299 	if (err != 0) {
300 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
301 			 "snf_start failed: %s", pcap_strerror(err));
302 		return -1;
303 	}
304 
305 	/*
306 	 * "select()" and "poll()" don't work on snf descriptors.
307 	 */
308 	p->selectable_fd = -1;
309 	p->linktype = DLT_EN10MB;
310 	p->read_op = snf_read;
311 	p->inject_op = snf_inject;
312 	p->setfilter_op = snf_setfilter;
313 	p->setdirection_op = NULL; /* Not implemented.*/
314 	p->set_datalink_op = snf_set_datalink;
315 	p->getnonblock_op = snf_getnonblock;
316 	p->setnonblock_op = snf_setnonblock;
317 	p->stats_op = snf_pcap_stats;
318 	p->cleanup_op = snf_platform_cleanup;
319 #ifdef SNF_HAVE_INJECT_API
320         ps->snf_inj = NULL;
321 #endif
322 	return 0;
323 }
324 
325 #define MAX_DESC_LENGTH 128
326 int
327 snf_findalldevs(pcap_if_t **devlistp, char *errbuf)
328 {
329 	pcap_if_t *devlist = NULL,*curdev,*prevdev;
330 	pcap_addr_t *curaddr;
331 	struct snf_ifaddrs *ifaddrs, *ifa;
332 	char desc[MAX_DESC_LENGTH];
333 	int ret;
334 
335 	if (snf_init(SNF_VERSION_API))
336 		return (-1);
337 
338 	if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL)
339 	{
340 		(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
341 			"snf_getifaddrs: %s", pcap_strerror(errno));
342 		return (-1);
343 	}
344 	ifa = ifaddrs;
345 	while (ifa)
346 	{
347 		/*
348 		 * Allocate a new entry
349 		 */
350 		curdev = (pcap_if_t *)malloc(sizeof(pcap_if_t));
351 		if (curdev == NULL) {
352 		(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
353 			"snf_findalldevs malloc: %s", pcap_strerror(errno));
354 			return (-1);
355 		}
356 		if (devlist == NULL) /* save first entry */
357 			devlist = curdev;
358 		else
359 			prevdev->next = curdev;
360 		/*
361 		 * Fill in the entry.
362 		 */
363 		curdev->next = NULL;
364 		curdev->name = strdup(ifa->snf_ifa_name);
365 		if (curdev->name == NULL) {
366 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
367 			    "snf_findalldevs strdup: %s", pcap_strerror(errno));
368 			free(curdev);
369 			return (-1);
370 		}
371 		(void)pcap_snprintf(desc,MAX_DESC_LENGTH,"Myricom snf%d",
372 				ifa->snf_ifa_portnum);
373 		curdev->description = strdup(desc);
374 		if (curdev->description == NULL) {
375 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
376 			"snf_findalldevs strdup1: %s", pcap_strerror(errno));
377 			free(curdev->name);
378 			free(curdev);
379 			return (-1);
380 		}
381 		curdev->addresses = NULL;
382 		curdev->flags = 0;
383 
384 		curaddr = (pcap_addr_t *)malloc(sizeof(pcap_addr_t));
385 		if (curaddr == NULL) {
386 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
387 			     "snf_findalldevs malloc1: %s", pcap_strerror(errno));
388 			free(curdev->description);
389 			free(curdev->name);
390 			free(curdev);
391 			return (-1);
392 		}
393 		curdev->addresses = curaddr;
394 		curaddr->next = NULL;
395 		curaddr->addr = (struct sockaddr*)malloc(sizeof(struct sockaddr_storage));
396 		if (curaddr->addr == NULL) {
397 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
398 			    "malloc2: %s", pcap_strerror(errno));
399 			free(curdev->description);
400 			free(curdev->name);
401 			free(curaddr);
402 			free(curdev);
403 			return (-1);
404 		}
405 		curaddr->addr->sa_family = AF_INET;
406 		curaddr->netmask = NULL;
407 		curaddr->broadaddr = NULL;
408 		curaddr->dstaddr = NULL;
409 		curaddr->next = NULL;
410 
411 		prevdev = curdev;
412 		ifa = ifa->snf_ifa_next;
413 	}
414 	snf_freeifaddrs(ifaddrs);
415 	*devlistp = devlist;
416 
417 	/*
418 	 * There are no platform-specific devices since each device
419 	 * exists as a regular Ethernet device.
420 	 */
421 	return 0;
422 }
423 
424 pcap_t *
425 snf_create(const char *device, char *ebuf, int *is_ours)
426 {
427 	pcap_t *p;
428 	int boardnum = -1;
429 	struct snf_ifaddrs *ifaddrs, *ifa;
430 	size_t devlen;
431 	struct pcap_snf *ps;
432 
433 	if (snf_init(SNF_VERSION_API)) {
434 		/* Can't initialize the API, so no SNF devices */
435 		*is_ours = 0;
436 		return NULL;
437 	}
438 
439 	/*
440 	 * Match a given interface name to our list of interface names, from
441 	 * which we can obtain the intended board number
442 	 */
443 	if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL) {
444 		/* Can't get SNF addresses */
445 		*is_ours = 0;
446 		return NULL;
447 	}
448 	devlen = strlen(device) + 1;
449 	ifa = ifaddrs;
450 	while (ifa) {
451 		if (!strncmp(device, ifa->snf_ifa_name, devlen)) {
452 			boardnum = ifa->snf_ifa_boardnum;
453 			break;
454 		}
455 		ifa = ifa->snf_ifa_next;
456 	}
457 	snf_freeifaddrs(ifaddrs);
458 
459 	if (ifa == NULL) {
460 		/*
461 		 * If we can't find the device by name, support the name "snfX"
462 		 * and "snf10gX" where X is the board number.
463 		 */
464 		if (sscanf(device, "snf10g%d", &boardnum) != 1 &&
465 		    sscanf(device, "snf%d", &boardnum) != 1) {
466 			/* Nope, not a supported name */
467 			*is_ours = 0;
468 			return NULL;
469 		    }
470 	}
471 
472 	/* OK, it's probably ours. */
473 	*is_ours = 1;
474 
475 	p = pcap_create_common(ebuf, sizeof (struct pcap_snf));
476 	if (p == NULL)
477 		return NULL;
478 	ps = p->priv;
479 
480 	/*
481 	 * We support microsecond and nanosecond time stamps.
482 	 */
483 	p->tstamp_precision_count = 2;
484 	p->tstamp_precision_list = malloc(2 * sizeof(u_int));
485 	if (p->tstamp_precision_list == NULL) {
486 		pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
487 		    pcap_strerror(errno));
488 		pcap_close(p);
489 		return NULL;
490 	}
491 	p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
492 	p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
493 
494 	p->activate_op = snf_activate;
495 	ps->snf_boardnum = boardnum;
496 	return p;
497 }
498 
499 #ifdef SNF_ONLY
500 /*
501  * This libpcap build supports only SNF cards, not regular network
502  * interfaces..
503  */
504 
505 /*
506  * There are no regular interfaces, just DAG interfaces.
507  */
508 int
509 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
510 {
511 	*alldevsp = NULL;
512 	return (0);
513 }
514 
515 /*
516  * Attempts to open a regular interface fail.
517  */
518 pcap_t *
519 pcap_create_interface(const char *device, char *errbuf)
520 {
521 	pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
522 	    "This version of libpcap only supports SNF cards");
523 	return NULL;
524 }
525 #endif
526