xref: /freebsd/contrib/libpcap/pcap-snf.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 #ifdef HAVE_CONFIG_H
2 #include "config.h"
3 #endif
4 
5 #include <sys/param.h>
6 
7 #include <stdlib.h>
8 #include <string.h>
9 #include <errno.h>
10 
11 #include <ctype.h>
12 #include <netinet/in.h>
13 #include <sys/mman.h>
14 #include <sys/socket.h>
15 #include <sys/types.h>
16 #include <unistd.h>
17 
18 #include <snf.h>
19 #if SNF_VERSION_API >= 0x0003
20 #define SNF_HAVE_INJECT_API
21 #endif
22 
23 #include "pcap-int.h"
24 #include "pcap-snf.h"
25 
26 /*
27  * Private data for capturing on SNF devices.
28  */
29 struct pcap_snf {
30 	snf_handle_t snf_handle; /* opaque device handle */
31 	snf_ring_t   snf_ring;   /* opaque device ring handle */
32 #ifdef SNF_HAVE_INJECT_API
33         snf_inject_t snf_inj;    /* inject handle, if inject is used */
34 #endif
35         int          snf_timeout;
36         int          snf_boardnum;
37 };
38 
39 static int
40 snf_set_datalink(pcap_t *p, int dlt)
41 {
42 	p->linktype = dlt;
43 	return (0);
44 }
45 
46 static int
47 snf_pcap_stats(pcap_t *p, struct pcap_stat *ps)
48 {
49 	struct snf_ring_stats stats;
50 	struct pcap_snf *snfps = p->priv;
51 	int rc;
52 
53 	if ((rc = snf_ring_getstats(snfps->snf_ring, &stats))) {
54 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_get_stats: %s",
55 			 pcap_strerror(rc));
56 		return -1;
57 	}
58 	ps->ps_recv = stats.ring_pkt_recv + stats.ring_pkt_overflow;
59 	ps->ps_drop = stats.ring_pkt_overflow;
60 	ps->ps_ifdrop = stats.nic_pkt_overflow + stats.nic_pkt_bad;
61 	return 0;
62 }
63 
64 static void
65 snf_platform_cleanup(pcap_t *p)
66 {
67 	struct pcap_snf *ps = p->priv;
68 
69 #ifdef SNF_HAVE_INJECT_API
70         if (ps->snf_inj)
71                 snf_inject_close(ps->snf_inj);
72 #endif
73 	snf_ring_close(ps->snf_ring);
74 	snf_close(ps->snf_handle);
75 	pcap_cleanup_live_common(p);
76 }
77 
78 static int
79 snf_getnonblock(pcap_t *p, char *errbuf)
80 {
81 	struct pcap_snf *ps = p->priv;
82 
83 	return (ps->snf_timeout == 0);
84 }
85 
86 static int
87 snf_setnonblock(pcap_t *p, int nonblock, char *errbuf)
88 {
89 	struct pcap_snf *ps = p->priv;
90 
91 	if (nonblock)
92 		ps->snf_timeout = 0;
93 	else {
94 		if (p->opt.timeout <= 0)
95 			ps->snf_timeout = -1; /* forever */
96 		else
97 			ps->snf_timeout = p->opt.timeout;
98 	}
99 	return (0);
100 }
101 
102 #define _NSEC_PER_SEC 1000000000
103 
104 static inline
105 struct timeval
106 snf_timestamp_to_timeval(const int64_t ts_nanosec, const int tstamp_precision)
107 {
108 	struct timeval tv;
109 	long tv_nsec;
110 
111 	if (ts_nanosec == 0)
112 		return (struct timeval) { 0, 0 };
113 
114 	tv.tv_sec = ts_nanosec / _NSEC_PER_SEC;
115 	tv_nsec = (ts_nanosec % _NSEC_PER_SEC);
116 
117 	/* libpcap expects tv_usec to be nanos if using nanosecond precision. */
118 	if (tstamp_precision == PCAP_TSTAMP_PRECISION_NANO)
119 		tv.tv_usec = tv_nsec;
120 	else
121 		tv.tv_usec = tv_nsec / 1000;
122 
123 	return tv;
124 }
125 
126 static int
127 snf_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
128 {
129 	struct pcap_snf *ps = p->priv;
130 	struct pcap_pkthdr hdr;
131 	int i, flags, err, caplen, n;
132 	struct snf_recv_req req;
133 	int nonblock, timeout;
134 
135 	if (!p)
136 		return -1;
137 
138 	n = 0;
139 	timeout = ps->snf_timeout;
140 	while (n < cnt || PACKET_COUNT_IS_UNLIMITED(cnt)) {
141 		/*
142 		 * Has "pcap_breakloop()" been called?
143 		 */
144 		if (p->break_loop) {
145 			if (n == 0) {
146 				p->break_loop = 0;
147 				return (-2);
148 			} else {
149 				return (n);
150 			}
151 		}
152 
153 		err = snf_ring_recv(ps->snf_ring, timeout, &req);
154 
155 		if (err) {
156 			if (err == EBUSY || err == EAGAIN) {
157 				return (n);
158 			}
159 			else if (err == EINTR) {
160 				timeout = 0;
161 				continue;
162 			}
163 			else {
164 				pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_read: %s",
165 				 	 pcap_strerror(err));
166 				return -1;
167 			}
168 		}
169 
170 		caplen = req.length;
171 		if (caplen > p->snapshot)
172 			caplen = p->snapshot;
173 
174 		if ((p->fcode.bf_insns == NULL) ||
175 		     bpf_filter(p->fcode.bf_insns, req.pkt_addr, req.length, caplen)) {
176 			hdr.ts = snf_timestamp_to_timeval(req.timestamp, p->opt.tstamp_precision);
177 			hdr.caplen = caplen;
178 			hdr.len = req.length;
179 			callback(user, &hdr, req.pkt_addr);
180 		}
181 		n++;
182 
183 		/* After one successful packet is received, we won't block
184 		* again for that timeout. */
185 		if (timeout != 0)
186 			timeout = 0;
187 	}
188 	return (n);
189 }
190 
191 static int
192 snf_setfilter(pcap_t *p, struct bpf_program *fp)
193 {
194 	if (!p)
195 		return -1;
196 	if (!fp) {
197 		strncpy(p->errbuf, "setfilter: No filter specified",
198 			sizeof(p->errbuf));
199 		return -1;
200 	}
201 
202 	/* Make our private copy of the filter */
203 
204 	if (install_bpf_program(p, fp) < 0)
205 		return -1;
206 
207 	return (0);
208 }
209 
210 static int
211 snf_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
212 {
213 #ifdef SNF_HAVE_INJECT_API
214 	struct pcap_snf *ps = p->priv;
215         int rc;
216         if (ps->snf_inj == NULL) {
217                 rc = snf_inject_open(ps->snf_boardnum, 0, &ps->snf_inj);
218                 if (rc) {
219                         pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
220                                 "snf_inject_open: %s", pcap_strerror(rc));
221                         return (-1);
222                 }
223         }
224 
225         rc = snf_inject_send(ps->snf_inj, -1, 0, buf, size);
226         if (!rc) {
227                 return (size);
228         }
229         else {
230                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_inject_send: %s",
231                          pcap_strerror(rc));
232                 return (-1);
233         }
234 #else
235 	strlcpy(p->errbuf, "Sending packets isn't supported with this snf version",
236 	    PCAP_ERRBUF_SIZE);
237 	return (-1);
238 #endif
239 }
240 
241 static int
242 snf_activate(pcap_t* p)
243 {
244 	struct pcap_snf *ps = p->priv;
245 	char *device = p->opt.device;
246 	const char *nr = NULL;
247 	int err;
248 	int flags = -1, ring_id = -1;
249 
250 	if (device == NULL) {
251 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
252 			 "device is NULL: %s", pcap_strerror(errno));
253 		return -1;
254 	}
255 
256 	/* In Libpcap, we set pshared by default if NUM_RINGS is set to > 1.
257 	 * Since libpcap isn't thread-safe */
258 	if ((nr = getenv("SNF_FLAGS")) && *nr)
259 		flags = strtol(nr, NULL, 0);
260 	else if ((nr = getenv("SNF_NUM_RINGS")) && *nr && atoi(nr) > 1)
261 		flags = SNF_F_PSHARED;
262 	else
263 		nr = NULL;
264 
265 	err = snf_open(ps->snf_boardnum,
266 			0, /* let SNF API parse SNF_NUM_RINGS, if set */
267 			NULL, /* default RSS, or use SNF_RSS_FLAGS env */
268 			0, /* default to SNF_DATARING_SIZE from env */
269 			flags, /* may want pshared */
270 			&ps->snf_handle);
271 	if (err != 0) {
272 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
273 			 "snf_open failed: %s", pcap_strerror(err));
274 		return -1;
275 	}
276 
277 	if ((nr = getenv("SNF_PCAP_RING_ID")) && *nr) {
278 		ring_id = (int) strtol(nr, NULL, 0);
279 	}
280 	err = snf_ring_open_id(ps->snf_handle, ring_id, &ps->snf_ring);
281 	if (err != 0) {
282 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
283 			 "snf_ring_open_id(ring=%d) failed: %s",
284 			 ring_id, pcap_strerror(err));
285 		return -1;
286 	}
287 
288 	if (p->opt.timeout <= 0)
289 		ps->snf_timeout = -1;
290 	else
291 		ps->snf_timeout = p->opt.timeout;
292 
293 	err = snf_start(ps->snf_handle);
294 	if (err != 0) {
295 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
296 			 "snf_start failed: %s", pcap_strerror(err));
297 		return -1;
298 	}
299 
300 	/*
301 	 * "select()" and "poll()" don't work on snf descriptors.
302 	 */
303 	p->selectable_fd = -1;
304 	p->linktype = DLT_EN10MB;
305 	p->read_op = snf_read;
306 	p->inject_op = snf_inject;
307 	p->setfilter_op = snf_setfilter;
308 	p->setdirection_op = NULL; /* Not implemented.*/
309 	p->set_datalink_op = snf_set_datalink;
310 	p->getnonblock_op = snf_getnonblock;
311 	p->setnonblock_op = snf_setnonblock;
312 	p->stats_op = snf_pcap_stats;
313 	p->cleanup_op = snf_platform_cleanup;
314 #ifdef SNF_HAVE_INJECT_API
315         ps->snf_inj = NULL;
316 #endif
317 	return 0;
318 }
319 
320 #define MAX_DESC_LENGTH 128
321 int
322 snf_findalldevs(pcap_if_t **devlistp, char *errbuf)
323 {
324 	pcap_if_t *devlist = NULL,*curdev,*prevdev;
325 	pcap_addr_t *curaddr;
326 	struct snf_ifaddrs *ifaddrs, *ifa;
327 	char desc[MAX_DESC_LENGTH];
328 	int ret;
329 
330 	if (snf_init(SNF_VERSION_API))
331 		return (-1);
332 
333 	if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL)
334 	{
335 		(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
336 			"snf_getifaddrs: %s", pcap_strerror(errno));
337 		return (-1);
338 	}
339 	ifa = ifaddrs;
340 	while (ifa)
341 	{
342 		/*
343 		 * Allocate a new entry
344 		 */
345 		curdev = (pcap_if_t *)malloc(sizeof(pcap_if_t));
346 		if (curdev == NULL) {
347 		(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
348 			"snf_findalldevs malloc: %s", pcap_strerror(errno));
349 			return (-1);
350 		}
351 		if (devlist == NULL) /* save first entry */
352 			devlist = curdev;
353 		else
354 			prevdev->next = curdev;
355 		/*
356 		 * Fill in the entry.
357 		 */
358 		curdev->next = NULL;
359 		curdev->name = strdup(ifa->snf_ifa_name);
360 		if (curdev->name == NULL) {
361 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
362 			    "snf_findalldevs strdup: %s", pcap_strerror(errno));
363 			free(curdev);
364 			return (-1);
365 		}
366 		(void)pcap_snprintf(desc,MAX_DESC_LENGTH,"Myricom snf%d",
367 				ifa->snf_ifa_portnum);
368 		curdev->description = strdup(desc);
369 		if (curdev->description == NULL) {
370 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
371 			"snf_findalldevs strdup1: %s", pcap_strerror(errno));
372 			free(curdev->name);
373 			free(curdev);
374 			return (-1);
375 		}
376 		curdev->addresses = NULL;
377 		curdev->flags = 0;
378 
379 		curaddr = (pcap_addr_t *)malloc(sizeof(pcap_addr_t));
380 		if (curaddr == NULL) {
381 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
382 			     "snf_findalldevs malloc1: %s", pcap_strerror(errno));
383 			free(curdev->description);
384 			free(curdev->name);
385 			free(curdev);
386 			return (-1);
387 		}
388 		curdev->addresses = curaddr;
389 		curaddr->next = NULL;
390 		curaddr->addr = (struct sockaddr*)malloc(sizeof(struct sockaddr_storage));
391 		if (curaddr->addr == NULL) {
392 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
393 			    "malloc2: %s", pcap_strerror(errno));
394 			free(curdev->description);
395 			free(curdev->name);
396 			free(curaddr);
397 			free(curdev);
398 			return (-1);
399 		}
400 		curaddr->addr->sa_family = AF_INET;
401 		curaddr->netmask = NULL;
402 		curaddr->broadaddr = NULL;
403 		curaddr->dstaddr = NULL;
404 		curaddr->next = NULL;
405 
406 		prevdev = curdev;
407 		ifa = ifa->snf_ifa_next;
408 	}
409 	snf_freeifaddrs(ifaddrs);
410 	*devlistp = devlist;
411 
412 	/*
413 	 * There are no platform-specific devices since each device
414 	 * exists as a regular Ethernet device.
415 	 */
416 	return 0;
417 }
418 
419 pcap_t *
420 snf_create(const char *device, char *ebuf, int *is_ours)
421 {
422 	pcap_t *p;
423 	int boardnum = -1;
424 	struct snf_ifaddrs *ifaddrs, *ifa;
425 	size_t devlen;
426 	struct pcap_snf *ps;
427 
428 	if (snf_init(SNF_VERSION_API)) {
429 		/* Can't initialize the API, so no SNF devices */
430 		*is_ours = 0;
431 		return NULL;
432 	}
433 
434 	/*
435 	 * Match a given interface name to our list of interface names, from
436 	 * which we can obtain the intended board number
437 	 */
438 	if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL) {
439 		/* Can't get SNF addresses */
440 		*is_ours = 0;
441 		return NULL;
442 	}
443 	devlen = strlen(device) + 1;
444 	ifa = ifaddrs;
445 	while (ifa) {
446 		if (!strncmp(device, ifa->snf_ifa_name, devlen)) {
447 			boardnum = ifa->snf_ifa_boardnum;
448 			break;
449 		}
450 		ifa = ifa->snf_ifa_next;
451 	}
452 	snf_freeifaddrs(ifaddrs);
453 
454 	if (ifa == NULL) {
455 		/*
456 		 * If we can't find the device by name, support the name "snfX"
457 		 * and "snf10gX" where X is the board number.
458 		 */
459 		if (sscanf(device, "snf10g%d", &boardnum) != 1 &&
460 		    sscanf(device, "snf%d", &boardnum) != 1) {
461 			/* Nope, not a supported name */
462 			*is_ours = 0;
463 			return NULL;
464 		    }
465 	}
466 
467 	/* OK, it's probably ours. */
468 	*is_ours = 1;
469 
470 	p = pcap_create_common(ebuf, sizeof (struct pcap_snf));
471 	if (p == NULL)
472 		return NULL;
473 	ps = p->priv;
474 
475 	/*
476 	 * We support microsecond and nanosecond time stamps.
477 	 */
478 	p->tstamp_precision_count = 2;
479 	p->tstamp_precision_list = malloc(2 * sizeof(u_int));
480 	if (p->tstamp_precision_list == NULL) {
481 		pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
482 		    pcap_strerror(errno));
483 		pcap_close(p);
484 		return NULL;
485 	}
486 	p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
487 	p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
488 
489 	p->activate_op = snf_activate;
490 	ps->snf_boardnum = boardnum;
491 	return p;
492 }
493 
494 #ifdef SNF_ONLY
495 /*
496  * This libpcap build supports only SNF cards, not regular network
497  * interfaces..
498  */
499 
500 /*
501  * There are no regular interfaces, just DAG interfaces.
502  */
503 int
504 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
505 {
506 	*alldevsp = NULL;
507 	return (0);
508 }
509 
510 /*
511  * Attempts to open a regular interface fail.
512  */
513 pcap_t *
514 pcap_create_interface(const char *device, char *errbuf)
515 {
516 	pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
517 	    "This version of libpcap only supports SNF cards");
518 	return NULL;
519 }
520 #endif
521