xref: /freebsd/contrib/libpcap/pcap-dag.c (revision fee65b7e21eeeb625dcaba8cf2b9e0cf5af83498)
1 /*
2  * pcap-dag.c: Packet capture interface for Endace DAG cards.
3  *
4  * Authors: Richard Littin, Sean Irvine ({richard,sean}@reeltwo.com)
5  * Modifications: Jesper Peterson
6  *                Koryn Grant
7  *                Stephen Donnelly <stephen.donnelly@endace.com>
8  */
9 
10 #ifdef HAVE_CONFIG_H
11 #include <config.h>
12 #endif
13 
14 #include <sys/param.h>			/* optionally get BSD define */
15 
16 #include <stdlib.h>
17 #include <string.h>
18 #include <errno.h>
19 
20 #include "pcap-int.h"
21 
22 #include <netinet/in.h>
23 #include <sys/mman.h>
24 #include <sys/socket.h>
25 #include <sys/types.h>
26 #include <unistd.h>
27 
28 struct mbuf;		/* Squelch compiler warnings on some platforms for */
29 struct rtentry;		/* declarations in <net/if.h> */
30 #include <net/if.h>
31 
32 #include "dagnew.h"
33 #include "dagapi.h"
34 #include "dagpci.h"
35 #include "dag_config_api.h"
36 
37 #include "pcap-dag.h"
38 
39 /*
40  * DAG devices have names beginning with "dag", followed by a number
41  * from 0 to DAG_MAX_BOARDS, then optionally a colon and a stream number
42  * from 0 to DAG_STREAM_MAX.
43  */
44 #ifndef DAG_MAX_BOARDS
45 #define DAG_MAX_BOARDS 32
46 #endif
47 
48 
49 #ifndef ERF_TYPE_AAL5
50 #define ERF_TYPE_AAL5               4
51 #endif
52 
53 #ifndef ERF_TYPE_MC_HDLC
54 #define ERF_TYPE_MC_HDLC            5
55 #endif
56 
57 #ifndef ERF_TYPE_MC_RAW
58 #define ERF_TYPE_MC_RAW             6
59 #endif
60 
61 #ifndef ERF_TYPE_MC_ATM
62 #define ERF_TYPE_MC_ATM             7
63 #endif
64 
65 #ifndef ERF_TYPE_MC_RAW_CHANNEL
66 #define ERF_TYPE_MC_RAW_CHANNEL     8
67 #endif
68 
69 #ifndef ERF_TYPE_MC_AAL5
70 #define ERF_TYPE_MC_AAL5            9
71 #endif
72 
73 #ifndef ERF_TYPE_COLOR_HDLC_POS
74 #define ERF_TYPE_COLOR_HDLC_POS     10
75 #endif
76 
77 #ifndef ERF_TYPE_COLOR_ETH
78 #define ERF_TYPE_COLOR_ETH          11
79 #endif
80 
81 #ifndef ERF_TYPE_MC_AAL2
82 #define ERF_TYPE_MC_AAL2            12
83 #endif
84 
85 #ifndef ERF_TYPE_IP_COUNTER
86 #define ERF_TYPE_IP_COUNTER         13
87 #endif
88 
89 #ifndef ERF_TYPE_TCP_FLOW_COUNTER
90 #define ERF_TYPE_TCP_FLOW_COUNTER   14
91 #endif
92 
93 #ifndef ERF_TYPE_DSM_COLOR_HDLC_POS
94 #define ERF_TYPE_DSM_COLOR_HDLC_POS 15
95 #endif
96 
97 #ifndef ERF_TYPE_DSM_COLOR_ETH
98 #define ERF_TYPE_DSM_COLOR_ETH      16
99 #endif
100 
101 #ifndef ERF_TYPE_COLOR_MC_HDLC_POS
102 #define ERF_TYPE_COLOR_MC_HDLC_POS  17
103 #endif
104 
105 #ifndef ERF_TYPE_AAL2
106 #define ERF_TYPE_AAL2               18
107 #endif
108 
109 #ifndef ERF_TYPE_COLOR_HASH_POS
110 #define ERF_TYPE_COLOR_HASH_POS     19
111 #endif
112 
113 #ifndef ERF_TYPE_COLOR_HASH_ETH
114 #define ERF_TYPE_COLOR_HASH_ETH     20
115 #endif
116 
117 #ifndef ERF_TYPE_INFINIBAND
118 #define ERF_TYPE_INFINIBAND         21
119 #endif
120 
121 #ifndef ERF_TYPE_IPV4
122 #define ERF_TYPE_IPV4               22
123 #endif
124 
125 #ifndef ERF_TYPE_IPV6
126 #define ERF_TYPE_IPV6               23
127 #endif
128 
129 #ifndef ERF_TYPE_RAW_LINK
130 #define ERF_TYPE_RAW_LINK           24
131 #endif
132 
133 #ifndef ERF_TYPE_INFINIBAND_LINK
134 #define ERF_TYPE_INFINIBAND_LINK    25
135 #endif
136 
137 #ifndef ERF_TYPE_META
138 #define ERF_TYPE_META               27
139 #endif
140 
141 #ifndef ERF_TYPE_PAD
142 #define ERF_TYPE_PAD                48
143 #endif
144 
145 #define ATM_CELL_SIZE		52
146 #define ATM_HDR_SIZE		4
147 
148 /*
149  * A header containing additional MTP information.
150  */
151 #define MTP2_SENT_OFFSET		0	/* 1 byte */
152 #define MTP2_ANNEX_A_USED_OFFSET	1	/* 1 byte */
153 #define MTP2_LINK_NUMBER_OFFSET		2	/* 2 bytes */
154 #define MTP2_HDR_LEN			4	/* length of the header */
155 
156 #define MTP2_ANNEX_A_NOT_USED      0
157 #define MTP2_ANNEX_A_USED          1
158 #define MTP2_ANNEX_A_USED_UNKNOWN  2
159 
160 /* SunATM pseudo header */
161 struct sunatm_hdr {
162 	unsigned char	flags;		/* destination and traffic type */
163 	unsigned char	vpi;		/* VPI */
164 	unsigned short	vci;		/* VCI */
165 };
166 
167 /*
168  * Private data for capturing on DAG devices.
169  */
170 struct pcap_dag {
171 	struct pcap_stat stat;
172 	u_char	*dag_mem_bottom;	/* DAG card current memory bottom pointer */
173 	u_char	*dag_mem_top;	/* DAG card current memory top pointer */
174 	int	dag_fcs_bits;	/* Number of checksum bits from link layer */
175 	int	dag_flags;	/* Flags */
176 	int	dag_stream;	/* DAG stream number */
177 	int	dag_timeout;	/* timeout specified to pcap_open_live.
178 				 * Same as in linux above, introduce
179 				 * generally? */
180 	dag_card_ref_t dag_ref; /* DAG Configuration/Status API card reference */
181 	dag_component_t dag_root;	/* DAG CSAPI Root component */
182 	attr_uuid_t drop_attr;  /* DAG Stream Drop Attribute handle, if available */
183 	struct timeval required_select_timeout;
184 				/* Timeout caller must use in event loops */
185 };
186 
187 typedef struct pcap_dag_node {
188 	struct pcap_dag_node *next;
189 	pcap_t *p;
190 	pid_t pid;
191 } pcap_dag_node_t;
192 
193 static pcap_dag_node_t *pcap_dags = NULL;
194 static int atexit_handler_installed = 0;
195 static const unsigned short endian_test_word = 0x0100;
196 
197 #define IS_BIGENDIAN() (*((unsigned char *)&endian_test_word))
198 
199 #define MAX_DAG_PACKET 65536
200 
201 static unsigned char TempPkt[MAX_DAG_PACKET];
202 
203 #ifndef HAVE_DAG_LARGE_STREAMS_API
204 #define dag_attach_stream64(a, b, c, d) dag_attach_stream(a, b, c, d)
205 #define dag_get_stream_poll64(a, b, c, d, e) dag_get_stream_poll(a, b, c, d, e)
206 #define dag_set_stream_poll64(a, b, c, d, e) dag_set_stream_poll(a, b, c, d, e)
207 #define dag_size_t uint32_t
208 #endif
209 
210 static int dag_stats(pcap_t *p, struct pcap_stat *ps);
211 static int dag_set_datalink(pcap_t *p, int dlt);
212 static int dag_get_datalink(pcap_t *p);
213 static int dag_setnonblock(pcap_t *p, int nonblock);
214 
215 static void
216 delete_pcap_dag(const pcap_t *p)
217 {
218 	pcap_dag_node_t *curr = NULL, *prev = NULL;
219 
220 	for (prev = NULL, curr = pcap_dags; curr != NULL && curr->p != p; prev = curr, curr = curr->next) {
221 		/* empty */
222 	}
223 
224 	if (curr != NULL && curr->p == p) {
225 		if (prev != NULL) {
226 			prev->next = curr->next;
227 		} else {
228 			pcap_dags = curr->next;
229 		}
230 	}
231 }
232 
233 /*
234  * Performs a graceful shutdown of the DAG card, frees dynamic memory held
235  * in the pcap_t structure, and closes the file descriptor for the DAG card.
236  */
237 
238 static void
239 dag_platform_cleanup(pcap_t *p)
240 {
241 	struct pcap_dag *pd = p->priv;
242 
243 	if(dag_stop_stream(p->fd, pd->dag_stream) < 0)
244 		fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
245 
246 	if(dag_detach_stream(p->fd, pd->dag_stream) < 0)
247 		fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
248 
249 	if(pd->dag_ref != NULL) {
250 		dag_config_dispose(pd->dag_ref);
251 		/*
252 		 * Note: we don't need to call close(p->fd) or
253 		 * dag_close(p->fd), as dag_config_dispose(pd->dag_ref)
254 		 * does this.
255 		 *
256 		 * Set p->fd to -1 to make sure that's not done.
257 		 */
258 		p->fd = -1;
259 		pd->dag_ref = NULL;
260 	}
261 	delete_pcap_dag(p);
262 	pcap_cleanup_live_common(p);
263 }
264 
265 static void
266 atexit_handler(void)
267 {
268 	while (pcap_dags != NULL) {
269 		if (pcap_dags->pid == getpid()) {
270 			if (pcap_dags->p != NULL)
271 				dag_platform_cleanup(pcap_dags->p);
272 		} else {
273 			delete_pcap_dag(pcap_dags->p);
274 		}
275 	}
276 }
277 
278 static int
279 new_pcap_dag(pcap_t *p)
280 {
281 	pcap_dag_node_t *node = NULL;
282 
283 	if ((node = malloc(sizeof(pcap_dag_node_t))) == NULL) {
284 		return -1;
285 	}
286 
287 	if (!atexit_handler_installed) {
288 		atexit(atexit_handler);
289 		atexit_handler_installed = 1;
290 	}
291 
292 	node->next = pcap_dags;
293 	node->p = p;
294 	node->pid = getpid();
295 
296 	pcap_dags = node;
297 
298 	return 0;
299 }
300 
301 static unsigned int
302 dag_erf_ext_header_count(const uint8_t *erf, size_t len)
303 {
304 	uint32_t hdr_num = 0;
305 	uint8_t  hdr_type;
306 
307 	/* basic sanity checks */
308 	if ( erf == NULL )
309 		return 0;
310 	if ( len < 16 )
311 		return 0;
312 
313 	/* check if we have any extension headers */
314 	if ( (erf[8] & 0x80) == 0x00 )
315 		return 0;
316 
317 	/* loop over the extension headers */
318 	do {
319 
320 		/* sanity check we have enough bytes */
321 		if ( len < (24 + (hdr_num * 8)) )
322 			return hdr_num;
323 
324 		/* get the header type */
325 		hdr_type = erf[(16 + (hdr_num * 8))];
326 		hdr_num++;
327 
328 	} while ( hdr_type & 0x80 );
329 
330 	return hdr_num;
331 }
332 
333 /*
334  *  Read at most max_packets from the capture stream and call the callback
335  *  for each of them. Returns the number of packets handled, -1 if an
336  *  error occurred, or -2 if we were told to break out of the loop.
337  */
338 static int
339 dag_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
340 {
341 	struct pcap_dag *pd = p->priv;
342 	unsigned int processed = 0;
343 	unsigned int nonblocking = pd->dag_flags & DAGF_NONBLOCK;
344 	unsigned int num_ext_hdr = 0;
345 	unsigned int ticks_per_second;
346 
347 	/* Get the next bufferful of packets (if necessary). */
348 	while (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size) {
349 
350 		/*
351 		 * Has "pcap_breakloop()" been called?
352 		 */
353 		if (p->break_loop) {
354 			/*
355 			 * Yes - clear the flag that indicates that
356 			 * it has, and return -2 to indicate that
357 			 * we were told to break out of the loop.
358 			 */
359 			p->break_loop = 0;
360 			return -2;
361 		}
362 
363 		/* dag_advance_stream() will block (unless nonblock is called)
364 		 * until 64kB of data has accumulated.
365 		 * If to_ms is set, it will timeout before 64kB has accumulated.
366 		 * We wait for 64kB because processing a few packets at a time
367 		 * can cause problems at high packet rates (>200kpps) due
368 		 * to inefficiencies.
369 		 * This does mean if to_ms is not specified the capture may 'hang'
370 		 * for long periods if the data rate is extremely slow (<64kB/sec)
371 		 * If non-block is specified it will return immediately. The user
372 		 * is then responsible for efficiency.
373 		 */
374 		if ( NULL == (pd->dag_mem_top = dag_advance_stream(p->fd, pd->dag_stream, &(pd->dag_mem_bottom))) ) {
375 		     return -1;
376 		}
377 
378 		if (nonblocking && (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size))
379 		{
380 			/* Pcap is configured to process only available packets, and there aren't any, return immediately. */
381 			return 0;
382 		}
383 
384 		if(!nonblocking &&
385 		   pd->dag_timeout &&
386 		   (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size))
387 		{
388 			/* Blocking mode, but timeout set and no data has arrived, return anyway.*/
389 			return 0;
390 		}
391 
392 	}
393 
394 	/*
395 	 * Process the packets.
396 	 *
397 	 * This assumes that a single buffer of packets will have
398 	 * <= INT_MAX packets, so the packet count doesn't overflow.
399 	 */
400 	while (pd->dag_mem_top - pd->dag_mem_bottom >= dag_record_size) {
401 
402 		unsigned short packet_len = 0;
403 		int caplen = 0;
404 		struct pcap_pkthdr	pcap_header;
405 
406 		dag_record_t *header = (dag_record_t *)(pd->dag_mem_bottom);
407 
408 		u_char *dp = ((u_char *)header); /* + dag_record_size; */
409 		unsigned short rlen;
410 
411 		/*
412 		 * Has "pcap_breakloop()" been called?
413 		 */
414 		if (p->break_loop) {
415 			/*
416 			 * Yes - clear the flag that indicates that
417 			 * it has, and return -2 to indicate that
418 			 * we were told to break out of the loop.
419 			 */
420 			p->break_loop = 0;
421 			return -2;
422 		}
423 
424 		rlen = ntohs(header->rlen);
425 		if (rlen < dag_record_size)
426 		{
427 			pcap_strlcpy(p->errbuf, "dag_read: record too small",
428 			    PCAP_ERRBUF_SIZE);
429 			return -1;
430 		}
431 		pd->dag_mem_bottom += rlen;
432 
433 		/* Count lost packets. */
434 		switch((header->type & 0x7f)) {
435 			/* in these types the color value overwrites the lctr */
436 		case ERF_TYPE_COLOR_HDLC_POS:
437 		case ERF_TYPE_COLOR_ETH:
438 		case ERF_TYPE_DSM_COLOR_HDLC_POS:
439 		case ERF_TYPE_DSM_COLOR_ETH:
440 		case ERF_TYPE_COLOR_MC_HDLC_POS:
441 		case ERF_TYPE_COLOR_HASH_ETH:
442 		case ERF_TYPE_COLOR_HASH_POS:
443 			break;
444 
445 		default:
446 			if ( (pd->drop_attr == kNullAttributeUuid) && (header->lctr) ) {
447 				pd->stat.ps_drop += ntohs(header->lctr);
448 			}
449 		}
450 
451 		if ((header->type & 0x7f) == ERF_TYPE_PAD) {
452 			continue;
453 		}
454 
455 		num_ext_hdr = dag_erf_ext_header_count(dp, rlen);
456 
457 		/* ERF encapsulation */
458 		/* The Extensible Record Format is not dropped for this kind of encapsulation,
459 		 * and will be handled as a pseudo header by the decoding application.
460 		 * The information carried in the ERF header and in the optional subheader (if present)
461 		 * could be merged with the libpcap information, to offer a better decoding.
462 		 * The packet length is
463 		 * o the length of the packet on the link (header->wlen),
464 		 * o plus the length of the ERF header (dag_record_size), as the length of the
465 		 *   pseudo header will be adjusted during the decoding,
466 		 * o plus the length of the optional subheader (if present).
467 		 *
468 		 * The capture length is header.rlen and the byte stuffing for alignment will be dropped
469 		 * if the capture length is greater than the packet length.
470 		 */
471 		if (p->linktype == DLT_ERF) {
472 			packet_len = ntohs(header->wlen) + dag_record_size;
473 			caplen = rlen;
474 			switch ((header->type & 0x7f)) {
475 			case ERF_TYPE_MC_AAL5:
476 			case ERF_TYPE_MC_ATM:
477 			case ERF_TYPE_MC_HDLC:
478 			case ERF_TYPE_MC_RAW_CHANNEL:
479 			case ERF_TYPE_MC_RAW:
480 			case ERF_TYPE_MC_AAL2:
481 			case ERF_TYPE_COLOR_MC_HDLC_POS:
482 				packet_len += 4; /* MC header */
483 				break;
484 
485 			case ERF_TYPE_COLOR_HASH_ETH:
486 			case ERF_TYPE_DSM_COLOR_ETH:
487 			case ERF_TYPE_COLOR_ETH:
488 			case ERF_TYPE_ETH:
489 				packet_len += 2; /* ETH header */
490 				break;
491 			} /* switch type */
492 
493 			/* Include ERF extension headers */
494 			packet_len += (8 * num_ext_hdr);
495 
496 			if (caplen > packet_len) {
497 				caplen = packet_len;
498 			}
499 		} else {
500 			/* Other kind of encapsulation according to the header Type */
501 
502 			/* Skip over generic ERF header */
503 			dp += dag_record_size;
504 			/* Skip over extension headers */
505 			dp += 8 * num_ext_hdr;
506 
507 			switch((header->type & 0x7f)) {
508 			case ERF_TYPE_ATM:
509 			case ERF_TYPE_AAL5:
510 				if ((header->type & 0x7f) == ERF_TYPE_AAL5) {
511 					packet_len = ntohs(header->wlen);
512 					caplen = rlen - dag_record_size;
513 				}
514 			case ERF_TYPE_MC_ATM:
515 				if ((header->type & 0x7f) == ERF_TYPE_MC_ATM) {
516 					caplen = packet_len = ATM_CELL_SIZE;
517 					dp+=4;
518 				}
519 			case ERF_TYPE_MC_AAL5:
520 				if ((header->type & 0x7f) == ERF_TYPE_MC_AAL5) {
521 					packet_len = ntohs(header->wlen);
522 					caplen = rlen - dag_record_size - 4;
523 					dp+=4;
524 				}
525 				/* Skip over extension headers */
526 				caplen -= (8 * num_ext_hdr);
527 
528 				if ((header->type & 0x7f) == ERF_TYPE_ATM) {
529 					caplen = packet_len = ATM_CELL_SIZE;
530 				}
531 				if (p->linktype == DLT_SUNATM) {
532 					struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
533 					unsigned long rawatm;
534 
535 					rawatm = ntohl(*((unsigned long *)dp));
536 					sunatm->vci = htons((rawatm >>  4) & 0xffff);
537 					sunatm->vpi = (rawatm >> 20) & 0x00ff;
538 					sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) |
539 						((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
540 						 ((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 :
541 						  ((dp[ATM_HDR_SIZE] == 0xaa &&
542 						    dp[ATM_HDR_SIZE+1] == 0xaa &&
543 						    dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
544 
545 				} else if (p->linktype == DLT_ATM_RFC1483) {
546 					packet_len -= ATM_HDR_SIZE;
547 					caplen -= ATM_HDR_SIZE;
548 					dp += ATM_HDR_SIZE;
549 				} else
550 					continue;
551 				break;
552 
553 			case ERF_TYPE_COLOR_HASH_ETH:
554 			case ERF_TYPE_DSM_COLOR_ETH:
555 			case ERF_TYPE_COLOR_ETH:
556 			case ERF_TYPE_ETH:
557 				if ((p->linktype != DLT_EN10MB) &&
558 				    (p->linktype != DLT_DOCSIS))
559 					continue;
560 				packet_len = ntohs(header->wlen);
561 				packet_len -= (pd->dag_fcs_bits >> 3);
562 				caplen = rlen - dag_record_size - 2;
563 				/* Skip over extension headers */
564 				caplen -= (8 * num_ext_hdr);
565 				if (caplen > packet_len) {
566 					caplen = packet_len;
567 				}
568 				dp += 2;
569 				break;
570 
571 			case ERF_TYPE_COLOR_HASH_POS:
572 			case ERF_TYPE_DSM_COLOR_HDLC_POS:
573 			case ERF_TYPE_COLOR_HDLC_POS:
574 			case ERF_TYPE_HDLC_POS:
575 				if ((p->linktype != DLT_CHDLC) &&
576 				    (p->linktype != DLT_PPP_SERIAL) &&
577 				    (p->linktype != DLT_FRELAY))
578 					continue;
579 				packet_len = ntohs(header->wlen);
580 				packet_len -= (pd->dag_fcs_bits >> 3);
581 				caplen = rlen - dag_record_size;
582 				/* Skip over extension headers */
583 				caplen -= (8 * num_ext_hdr);
584 				if (caplen > packet_len) {
585 					caplen = packet_len;
586 				}
587 				break;
588 
589 			case ERF_TYPE_COLOR_MC_HDLC_POS:
590 			case ERF_TYPE_MC_HDLC:
591 				if ((p->linktype != DLT_CHDLC) &&
592 				    (p->linktype != DLT_PPP_SERIAL) &&
593 				    (p->linktype != DLT_FRELAY) &&
594 				    (p->linktype != DLT_MTP2) &&
595 				    (p->linktype != DLT_MTP2_WITH_PHDR) &&
596 				    (p->linktype != DLT_LAPD))
597 					continue;
598 				packet_len = ntohs(header->wlen);
599 				packet_len -= (pd->dag_fcs_bits >> 3);
600 				caplen = rlen - dag_record_size - 4;
601 				/* Skip over extension headers */
602 				caplen -= (8 * num_ext_hdr);
603 				if (caplen > packet_len) {
604 					caplen = packet_len;
605 				}
606 				/* jump the MC_HDLC_HEADER */
607 				dp += 4;
608 #ifdef DLT_MTP2_WITH_PHDR
609 				if (p->linktype == DLT_MTP2_WITH_PHDR) {
610 					/* Add the MTP2 Pseudo Header */
611 					caplen += MTP2_HDR_LEN;
612 					packet_len += MTP2_HDR_LEN;
613 
614 					TempPkt[MTP2_SENT_OFFSET] = 0;
615 					TempPkt[MTP2_ANNEX_A_USED_OFFSET] = MTP2_ANNEX_A_USED_UNKNOWN;
616 					*(TempPkt+MTP2_LINK_NUMBER_OFFSET) = ((header->rec.mc_hdlc.mc_header>>16)&0x01);
617 					*(TempPkt+MTP2_LINK_NUMBER_OFFSET+1) = ((header->rec.mc_hdlc.mc_header>>24)&0xff);
618 					memcpy(TempPkt+MTP2_HDR_LEN, dp, caplen);
619 					dp = TempPkt;
620 				}
621 #endif
622 				break;
623 
624 			case ERF_TYPE_IPV4:
625 				if ((p->linktype != DLT_RAW) &&
626 				    (p->linktype != DLT_IPV4))
627 					continue;
628 				packet_len = ntohs(header->wlen);
629 				caplen = rlen - dag_record_size;
630 				/* Skip over extension headers */
631 				caplen -= (8 * num_ext_hdr);
632 				if (caplen > packet_len) {
633 					caplen = packet_len;
634 				}
635 				break;
636 
637 			case ERF_TYPE_IPV6:
638 				if ((p->linktype != DLT_RAW) &&
639 				    (p->linktype != DLT_IPV6))
640 					continue;
641 				packet_len = ntohs(header->wlen);
642 				caplen = rlen - dag_record_size;
643 				/* Skip over extension headers */
644 				caplen -= (8 * num_ext_hdr);
645 				if (caplen > packet_len) {
646 					caplen = packet_len;
647 				}
648 				break;
649 
650 			/* These types have no matching 'native' DLT, but can be used with DLT_ERF above */
651 			case ERF_TYPE_MC_RAW:
652 			case ERF_TYPE_MC_RAW_CHANNEL:
653 			case ERF_TYPE_IP_COUNTER:
654 			case ERF_TYPE_TCP_FLOW_COUNTER:
655 			case ERF_TYPE_INFINIBAND:
656 			case ERF_TYPE_RAW_LINK:
657 			case ERF_TYPE_INFINIBAND_LINK:
658 			default:
659 				/* Unhandled ERF type.
660 				 * Ignore rather than generating error
661 				 */
662 				continue;
663 			} /* switch type */
664 
665 		} /* ERF encapsulation */
666 
667 		if (caplen > p->snapshot)
668 			caplen = p->snapshot;
669 
670 		/* Run the packet filter if there is one. */
671 		if ((p->fcode.bf_insns == NULL) || pcap_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
672 
673 			/* convert between timestamp formats */
674 			register unsigned long long ts;
675 
676 			if (IS_BIGENDIAN()) {
677 				ts = SWAPLL(header->ts);
678 			} else {
679 				ts = header->ts;
680 			}
681 
682 			switch (p->opt.tstamp_precision) {
683 			case PCAP_TSTAMP_PRECISION_NANO:
684 				ticks_per_second = 1000000000;
685 				break;
686 			case PCAP_TSTAMP_PRECISION_MICRO:
687 			default:
688 				ticks_per_second = 1000000;
689 				break;
690 
691 			}
692 			pcap_header.ts.tv_sec = ts >> 32;
693 			ts = (ts & 0xffffffffULL) * ticks_per_second;
694 			ts += 0x80000000; /* rounding */
695 			pcap_header.ts.tv_usec = ts >> 32;
696 			if (pcap_header.ts.tv_usec >= ticks_per_second) {
697 				pcap_header.ts.tv_usec -= ticks_per_second;
698 				pcap_header.ts.tv_sec++;
699 			}
700 
701 			/* Fill in our own header data */
702 			pcap_header.caplen = caplen;
703 			pcap_header.len = packet_len;
704 
705 			/* Count the packet. */
706 			pd->stat.ps_recv++;
707 
708 			/* Call the user supplied callback function */
709 			callback(user, &pcap_header, dp);
710 
711 			/* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
712 			processed++;
713 			if (processed == cnt && !PACKET_COUNT_IS_UNLIMITED(cnt))
714 			{
715 				/* Reached the user-specified limit. */
716 				return cnt;
717 			}
718 		}
719 	}
720 
721 	return processed;
722 }
723 
724 static int
725 dag_inject(pcap_t *p, const void *buf _U_, int size _U_)
726 {
727 	pcap_strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
728 	    PCAP_ERRBUF_SIZE);
729 	return (-1);
730 }
731 
732 /*
733  *  Get a handle for a live capture from the given DAG device.  Passing a NULL
734  *  device will result in a failure.  The promisc flag is ignored because DAG
735  *  cards are always promiscuous.  The to_ms parameter is used in setting the
736  *  API polling parameters.
737  *
738  *  snaplen is now also ignored, until we get per-stream slen support. Set
739  *  slen with appropriate DAG tool BEFORE pcap_activate().
740  *
741  *  See also pcap(3).
742  */
743 static int dag_activate(pcap_t* p)
744 {
745 	struct pcap_dag *pd = p->priv;
746 	char *s;
747 	int n;
748 	daginf_t* daginf;
749 	char * newDev = NULL;
750 	char * device = p->opt.device;
751 	int ret;
752 	dag_size_t mindata;
753 	struct timeval maxwait;
754 	struct timeval poll;
755 
756 	if (device == NULL) {
757 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "device is NULL");
758 		return PCAP_ERROR;
759 	}
760 
761 	/* Initialize some components of the pcap structure. */
762 	newDev = (char *)malloc(strlen(device) + 16);
763 	if (newDev == NULL) {
764 		ret = PCAP_ERROR;
765 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
766 		    errno, "Can't allocate string for device name");
767 		goto fail;
768 	}
769 
770 	/* Parse input name to get dag device and stream number if provided */
771 	if (dag_parse_name(device, newDev, strlen(device) + 16, &pd->dag_stream) < 0) {
772 		/*
773 		 * XXX - it'd be nice if this indicated what was wrong
774 		 * with the name.  Does this reliably set errno?
775 		 * Should this return PCAP_ERROR_NO_SUCH_DEVICE in some
776 		 * cases?
777 		 */
778 		ret = PCAP_ERROR;
779 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
780 		    errno, "dag_parse_name");
781 		goto fail;
782 	}
783 	device = newDev;
784 
785 	if (pd->dag_stream%2) {
786 		ret = PCAP_ERROR;
787 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: tx (even numbered) streams not supported for capture");
788 		goto fail;
789 	}
790 
791 	/* setup device parameters */
792 	if((pd->dag_ref = dag_config_init((char *)device)) == NULL) {
793 		/*
794 		 * XXX - does this reliably set errno?
795 		 */
796 		if (errno == ENOENT) {
797 			/*
798 			 * There's nothing more to say, so clear
799 			 * the error message.
800 			 */
801 			ret = PCAP_ERROR_NO_SUCH_DEVICE;
802 			p->errbuf[0] = '\0';
803 		} else if (errno == EPERM || errno == EACCES) {
804 			ret = PCAP_ERROR_PERM_DENIED;
805 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
806 			    "Attempt to open %s failed with %s - additional privileges may be required",
807 			    device, (errno == EPERM) ? "EPERM" : "EACCES");
808 		} else {
809 			ret = PCAP_ERROR;
810 			pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
811 			    errno, "dag_config_init %s", device);
812 		}
813 		goto fail;
814 	}
815 
816 	if((p->fd = dag_config_get_card_fd(pd->dag_ref)) < 0) {
817 		/*
818 		 * XXX - does this reliably set errno?
819 		 */
820 		ret = PCAP_ERROR;
821 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
822 		    errno, "dag_config_get_card_fd %s", device);
823 		goto failclose;
824 	}
825 
826 	/* Open requested stream. Can fail if already locked or on error */
827 	if (dag_attach_stream64(p->fd, pd->dag_stream, 0, 0) < 0) {
828 		ret = PCAP_ERROR;
829 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
830 		    errno, "dag_attach_stream");
831 		goto failclose;
832 	}
833 
834 	/* Try to find Stream Drop attribute */
835 	pd->drop_attr = kNullAttributeUuid;
836 	pd->dag_root = dag_config_get_root_component(pd->dag_ref);
837 	if ( dag_component_get_subcomponent(pd->dag_root, kComponentStreamFeatures, 0) )
838 	{
839 		pd->drop_attr = dag_config_get_indexed_attribute_uuid(pd->dag_ref, kUint32AttributeStreamDropCount, pd->dag_stream/2);
840 	}
841 
842 	/* Set up default poll parameters for stream
843 	 * Can be overridden by pcap_set_nonblock()
844 	 */
845 	if (dag_get_stream_poll64(p->fd, pd->dag_stream,
846 				&mindata, &maxwait, &poll) < 0) {
847 		ret = PCAP_ERROR;
848 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
849 		    errno, "dag_get_stream_poll");
850 		goto faildetach;
851 	}
852 
853 	/* Use the poll time as the required select timeout for callers
854 	 * who are using select()/etc. in an event loop waiting for
855 	 * packets to arrive.
856 	 */
857 	pd->required_select_timeout = poll;
858 	p->required_select_timeout = &pd->required_select_timeout;
859 
860 	/*
861 	 * Turn a negative snapshot value (invalid), a snapshot value of
862 	 * 0 (unspecified), or a value bigger than the normal maximum
863 	 * value, into the maximum allowed value.
864 	 *
865 	 * If some application really *needs* a bigger snapshot
866 	 * length, we should just increase MAXIMUM_SNAPLEN.
867 	 */
868 	if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
869 		p->snapshot = MAXIMUM_SNAPLEN;
870 
871 	if (p->opt.immediate) {
872 		/* Call callback immediately.
873 		 * XXX - is this the right way to p this?
874 		 */
875 		mindata = 0;
876 	} else {
877 		/* Amount of data to collect in Bytes before calling callbacks.
878 		 * Important for efficiency, but can introduce latency
879 		 * at low packet rates if to_ms not set!
880 		 */
881 		mindata = 65536;
882 	}
883 
884 	/* Obey opt.timeout (was to_ms) if supplied. This is a good idea!
885 	 * Recommend 10-100ms. Calls will time out even if no data arrived.
886 	 */
887 	maxwait.tv_sec = p->opt.timeout/1000;
888 	maxwait.tv_usec = (p->opt.timeout%1000) * 1000;
889 
890 	if (dag_set_stream_poll64(p->fd, pd->dag_stream,
891 				mindata, &maxwait, &poll) < 0) {
892 		ret = PCAP_ERROR;
893 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
894 		    errno, "dag_set_stream_poll");
895 		goto faildetach;
896 	}
897 
898         /* XXX Not calling dag_configure() to set slen; this is unsafe in
899 	 * multi-stream environments as the gpp config is global.
900          * Once the firmware provides 'per-stream slen' this can be supported
901 	 * again via the Config API without side-effects */
902 #if 0
903 	/* set the card snap length to the specified snaplen parameter */
904 	/* This is a really bad idea, as different cards have different
905 	 * valid slen ranges. Should fix in Config API. */
906 	if (p->snapshot == 0 || p->snapshot > MAX_DAG_SNAPLEN) {
907 		p->snapshot = MAX_DAG_SNAPLEN;
908 	} else if (snaplen < MIN_DAG_SNAPLEN) {
909 		p->snapshot = MIN_DAG_SNAPLEN;
910 	}
911 	/* snap len has to be a multiple of 4 */
912 #endif
913 
914 	if(dag_start_stream(p->fd, pd->dag_stream) < 0) {
915 		ret = PCAP_ERROR;
916 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
917 		    errno, "dag_start_stream %s", device);
918 		goto faildetach;
919 	}
920 
921 	/*
922 	 * Important! You have to ensure bottom is properly
923 	 * initialized to zero on startup, it won't give you
924 	 * a compiler warning if you make this mistake!
925 	 */
926 	pd->dag_mem_bottom = 0;
927 	pd->dag_mem_top = 0;
928 
929 	/*
930 	 * Find out how many FCS bits we should strip.
931 	 * First, query the card to see if it strips the FCS.
932 	 */
933 	daginf = dag_info(p->fd);
934 	if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code))	{
935 		/* DAG 4.2S and 4.23S already strip the FCS.  Stripping the final word again truncates the packet. */
936 		pd->dag_fcs_bits = 0;
937 
938 		/* Note that no FCS will be supplied. */
939 		p->linktype_ext = LT_FCS_DATALINK_EXT(0);
940 	} else {
941 		/*
942 		 * Start out assuming it's 32 bits.
943 		 */
944 		pd->dag_fcs_bits = 32;
945 
946 		/* Allow an environment variable to override. */
947 		if ((s = getenv("ERF_FCS_BITS")) != NULL) {
948 			if ((n = atoi(s)) == 0 || n == 16 || n == 32) {
949 				pd->dag_fcs_bits = n;
950 			} else {
951 				ret = PCAP_ERROR;
952 				snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
953 					"pcap_activate %s: bad ERF_FCS_BITS value (%d) in environment", device, n);
954 				goto failstop;
955 			}
956 		}
957 
958 		/*
959 		 * Did the user request that they not be stripped?
960 		 */
961 		if ((s = getenv("ERF_DONT_STRIP_FCS")) != NULL) {
962 			/* Yes.  Note the number of 16-bit words that will be
963 			   supplied. */
964 			p->linktype_ext = LT_FCS_DATALINK_EXT(pd->dag_fcs_bits/16);
965 
966 			/* And don't strip them. */
967 			pd->dag_fcs_bits = 0;
968 		}
969 	}
970 
971 	pd->dag_timeout	= p->opt.timeout;
972 
973 	p->linktype = -1;
974 	if (dag_get_datalink(p) < 0) {
975 		ret = PCAP_ERROR;
976 		goto failstop;
977 	}
978 
979 	p->bufsize = 0;
980 
981 	if (new_pcap_dag(p) < 0) {
982 		ret = PCAP_ERROR;
983 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
984 		    errno, "new_pcap_dag %s", device);
985 		goto failstop;
986 	}
987 
988 	/*
989 	 * "select()" and "poll()" don't work on DAG device descriptors.
990 	 */
991 	p->selectable_fd = -1;
992 
993 	if (newDev != NULL) {
994 		free((char *)newDev);
995 	}
996 
997 	p->read_op = dag_read;
998 	p->inject_op = dag_inject;
999 	p->setfilter_op = install_bpf_program;
1000 	p->setdirection_op = NULL; /* Not implemented.*/
1001 	p->set_datalink_op = dag_set_datalink;
1002 	p->getnonblock_op = pcap_getnonblock_fd;
1003 	p->setnonblock_op = dag_setnonblock;
1004 	p->stats_op = dag_stats;
1005 	p->cleanup_op = dag_platform_cleanup;
1006 	pd->stat.ps_drop = 0;
1007 	pd->stat.ps_recv = 0;
1008 	pd->stat.ps_ifdrop = 0;
1009 	return 0;
1010 
1011 failstop:
1012 	if (dag_stop_stream(p->fd, pd->dag_stream) < 0) {
1013 		fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
1014 	}
1015 
1016 faildetach:
1017 	if (dag_detach_stream(p->fd, pd->dag_stream) < 0)
1018 		fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
1019 
1020 failclose:
1021 	dag_config_dispose(pd->dag_ref);
1022 	/*
1023 	 * Note: we don't need to call close(p->fd) or dag_close(p->fd),
1024 	 * as dag_config_dispose(pd->dag_ref) does this.
1025 	 *
1026 	 * Set p->fd to -1 to make sure that's not done.
1027 	 */
1028 	p->fd = -1;
1029 	pd->dag_ref = NULL;
1030 	delete_pcap_dag(p);
1031 
1032 fail:
1033 	pcap_cleanup_live_common(p);
1034 	if (newDev != NULL) {
1035 		free((char *)newDev);
1036 	}
1037 
1038 	return ret;
1039 }
1040 
1041 pcap_t *dag_create(const char *device, char *ebuf, int *is_ours)
1042 {
1043 	const char *cp;
1044 	char *cpend;
1045 	long devnum;
1046 	pcap_t *p;
1047 	long stream = 0;
1048 
1049 	/* Does this look like a DAG device? */
1050 	cp = strrchr(device, '/');
1051 	if (cp == NULL)
1052 		cp = device;
1053 	/* Does it begin with "dag"? */
1054 	if (strncmp(cp, "dag", 3) != 0) {
1055 		/* Nope, doesn't begin with "dag" */
1056 		*is_ours = 0;
1057 		return NULL;
1058 	}
1059 	/* Yes - is "dag" followed by a number from 0 to DAG_MAX_BOARDS-1 */
1060 	cp += 3;
1061 	devnum = strtol(cp, &cpend, 10);
1062 	if (*cpend == ':') {
1063 		/* Followed by a stream number. */
1064 		stream = strtol(++cpend, &cpend, 10);
1065 	}
1066 
1067 	if (cpend == cp || *cpend != '\0') {
1068 		/* Not followed by a number. */
1069 		*is_ours = 0;
1070 		return NULL;
1071 	}
1072 
1073 	if (devnum < 0 || devnum >= DAG_MAX_BOARDS) {
1074 		/* Followed by a non-valid number. */
1075 		*is_ours = 0;
1076 		return NULL;
1077 	}
1078 
1079 	if (stream <0 || stream >= DAG_STREAM_MAX) {
1080 		/* Followed by a non-valid stream number. */
1081 		*is_ours = 0;
1082 		return NULL;
1083 	}
1084 
1085 	/* OK, it's probably ours. */
1086 	*is_ours = 1;
1087 
1088 	p = PCAP_CREATE_COMMON(ebuf, struct pcap_dag);
1089 	if (p == NULL)
1090 		return NULL;
1091 
1092 	p->activate_op = dag_activate;
1093 
1094 	/*
1095 	 * We claim that we support microsecond and nanosecond time
1096 	 * stamps.
1097 	 *
1098 	 * XXX Our native precision is 2^-32s, but libpcap doesn't support
1099 	 * power of two precisions yet. We can convert to either MICRO or NANO.
1100 	 */
1101 	p->tstamp_precision_list = malloc(2 * sizeof(u_int));
1102 	if (p->tstamp_precision_list == NULL) {
1103 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1104 		    errno, "malloc");
1105 		pcap_close(p);
1106 		return NULL;
1107 	}
1108 	p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
1109 	p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
1110 	p->tstamp_precision_count = 2;
1111 	return p;
1112 }
1113 
1114 static int
1115 dag_stats(pcap_t *p, struct pcap_stat *ps) {
1116 	struct pcap_dag *pd = p->priv;
1117 	uint32_t stream_drop;
1118 	dag_err_t dag_error;
1119 
1120 	/*
1121 	 * Packet records received (ps_recv) are counted in dag_read().
1122 	 * Packet records dropped (ps_drop) are read from Stream Drop attribute if present,
1123 	 * otherwise integrate the ERF Header lctr counts (if available) in dag_read().
1124 	 * We are reporting that no records are dropped by the card/driver (ps_ifdrop).
1125 	 */
1126 
1127 	if(pd->drop_attr != kNullAttributeUuid) {
1128 		/* Note this counter is cleared at start of capture and will wrap at UINT_MAX.
1129 		 * The application is responsible for polling ps_drop frequently enough
1130 		 * to detect each wrap and integrate total drop with a wider counter */
1131 		if ((dag_error = dag_config_get_uint32_attribute_ex(pd->dag_ref, pd->drop_attr, &stream_drop)) == kDagErrNone) {
1132 			pd->stat.ps_drop = stream_drop;
1133 		} else {
1134 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "reading stream drop attribute: %s",
1135 				 dag_config_strerror(dag_error));
1136 			return -1;
1137 		}
1138 	}
1139 
1140 	*ps = pd->stat;
1141 
1142 	return 0;
1143 }
1144 
1145 /*
1146  * Add all DAG devices.
1147  */
1148 int
1149 dag_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
1150 {
1151 	char name[12];	/* XXX - pick a size */
1152 	int c;
1153 	char dagname[DAGNAME_BUFSIZE];
1154 	int dagstream;
1155 	int dagfd;
1156 	dag_card_inf_t *inf;
1157 	char *description;
1158 	int stream, rxstreams;
1159 
1160 	/* Try all the DAGs 0-DAG_MAX_BOARDS */
1161 	for (c = 0; c < DAG_MAX_BOARDS; c++) {
1162 		snprintf(name, 12, "dag%d", c);
1163 		if (-1 == dag_parse_name(name, dagname, DAGNAME_BUFSIZE, &dagstream))
1164 		{
1165 			(void) snprintf(errbuf, PCAP_ERRBUF_SIZE,
1166 			    "dag: device name %s can't be parsed", name);
1167 			return (-1);
1168 		}
1169 		if ( (dagfd = dag_open(dagname)) >= 0 ) {
1170 			description = NULL;
1171 			if ((inf = dag_pciinfo(dagfd)))
1172 				description = dag_device_name(inf->device_code, 1);
1173 			/*
1174 			 * XXX - is there a way to determine whether
1175 			 * the card is plugged into a network or not?
1176 			 * If so, we should check that and set
1177 			 * PCAP_IF_CONNECTION_STATUS_CONNECTED or
1178 			 * PCAP_IF_CONNECTION_STATUS_DISCONNECTED.
1179 			 *
1180 			 * Also, are there notions of "up" and "running"?
1181 			 */
1182 			if (add_dev(devlistp, name, 0, description, errbuf) == NULL) {
1183 				/*
1184 				 * Failure.
1185 				 */
1186 				return (-1);
1187 			}
1188 			rxstreams = dag_rx_get_stream_count(dagfd);
1189 			for(stream=0;stream<DAG_STREAM_MAX;stream+=2) {
1190 				if (0 == dag_attach_stream64(dagfd, stream, 0, 0)) {
1191 					dag_detach_stream(dagfd, stream);
1192 
1193 					snprintf(name,  10, "dag%d:%d", c, stream);
1194 					if (add_dev(devlistp, name, 0, description, errbuf) == NULL) {
1195 						/*
1196 						 * Failure.
1197 						 */
1198 						return (-1);
1199 					}
1200 
1201 					rxstreams--;
1202 					if(rxstreams <= 0) {
1203 						break;
1204 					}
1205 				}
1206 			}
1207 			dag_close(dagfd);
1208 		}
1209 
1210 	}
1211 	return (0);
1212 }
1213 
1214 static int
1215 dag_set_datalink(pcap_t *p, int dlt)
1216 {
1217 	p->linktype = dlt;
1218 
1219 	return (0);
1220 }
1221 
1222 static int
1223 dag_setnonblock(pcap_t *p, int nonblock)
1224 {
1225 	struct pcap_dag *pd = p->priv;
1226 	dag_size_t mindata;
1227 	struct timeval maxwait;
1228 	struct timeval poll;
1229 
1230 	/*
1231 	 * Set non-blocking mode on the FD.
1232 	 * XXX - is that necessary?  If not, don't bother calling it,
1233 	 * and have a "dag_getnonblock()" function that looks at
1234 	 * "pd->dag_flags".
1235 	 */
1236 	if (pcap_setnonblock_fd(p, nonblock) < 0)
1237 		return (-1);
1238 
1239 	if (dag_get_stream_poll64(p->fd, pd->dag_stream,
1240 				&mindata, &maxwait, &poll) < 0) {
1241 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
1242 		    errno, "dag_get_stream_poll");
1243 		return -1;
1244 	}
1245 
1246 	/* Amount of data to collect in Bytes before calling callbacks.
1247 	 * Important for efficiency, but can introduce latency
1248 	 * at low packet rates if to_ms not set!
1249 	 */
1250 	if(nonblock)
1251 		mindata = 0;
1252 	else
1253 		mindata = 65536;
1254 
1255 	if (dag_set_stream_poll64(p->fd, pd->dag_stream,
1256 				mindata, &maxwait, &poll) < 0) {
1257 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
1258 		    errno, "dag_set_stream_poll");
1259 		return -1;
1260 	}
1261 
1262 	if (nonblock) {
1263 		pd->dag_flags |= DAGF_NONBLOCK;
1264 	} else {
1265 		pd->dag_flags &= ~DAGF_NONBLOCK;
1266 	}
1267 	return (0);
1268 }
1269 
1270 static int
1271 dag_get_datalink(pcap_t *p)
1272 {
1273 	struct pcap_dag *pd = p->priv;
1274 	int index=0, dlt_index=0;
1275 	uint8_t types[255];
1276 
1277 	memset(types, 0, 255);
1278 
1279 	if (p->dlt_list == NULL && (p->dlt_list = malloc(255*sizeof(*(p->dlt_list)))) == NULL) {
1280 		pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
1281 		    errno, "malloc");
1282 		return (-1);
1283 	}
1284 
1285 	p->linktype = 0;
1286 
1287 #ifdef HAVE_DAG_GET_STREAM_ERF_TYPES
1288 	/* Get list of possible ERF types for this card */
1289 	if (dag_get_stream_erf_types(p->fd, pd->dag_stream, types, 255) < 0) {
1290 		pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
1291 		    errno, "dag_get_stream_erf_types");
1292 		return (-1);
1293 	}
1294 
1295 	while (types[index]) {
1296 
1297 #elif defined HAVE_DAG_GET_ERF_TYPES
1298 	/* Get list of possible ERF types for this card */
1299 	if (dag_get_erf_types(p->fd, types, 255) < 0) {
1300 		pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
1301 		    errno, "dag_get_erf_types");
1302 		return (-1);
1303 	}
1304 
1305 	while (types[index]) {
1306 #else
1307 	/* Check the type through a dagapi call. */
1308 	types[index] = dag_linktype(p->fd);
1309 
1310 	{
1311 #endif
1312 		switch((types[index] & 0x7f)) {
1313 
1314 		case ERF_TYPE_HDLC_POS:
1315 		case ERF_TYPE_COLOR_HDLC_POS:
1316 		case ERF_TYPE_DSM_COLOR_HDLC_POS:
1317 		case ERF_TYPE_COLOR_HASH_POS:
1318 
1319 			if (p->dlt_list != NULL) {
1320 				p->dlt_list[dlt_index++] = DLT_CHDLC;
1321 				p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1322 				p->dlt_list[dlt_index++] = DLT_FRELAY;
1323 			}
1324 			if(!p->linktype)
1325 				p->linktype = DLT_CHDLC;
1326 			break;
1327 
1328 		case ERF_TYPE_ETH:
1329 		case ERF_TYPE_COLOR_ETH:
1330 		case ERF_TYPE_DSM_COLOR_ETH:
1331 		case ERF_TYPE_COLOR_HASH_ETH:
1332 			/*
1333 			 * This is (presumably) a real Ethernet capture; give it a
1334 			 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
1335 			 * that an application can let you choose it, in case you're
1336 			 * capturing DOCSIS traffic that a Cisco Cable Modem
1337 			 * Termination System is putting out onto an Ethernet (it
1338 			 * doesn't put an Ethernet header onto the wire, it puts raw
1339 			 * DOCSIS frames out on the wire inside the low-level
1340 			 * Ethernet framing).
1341 			 */
1342 			if (p->dlt_list != NULL) {
1343 				p->dlt_list[dlt_index++] = DLT_EN10MB;
1344 				p->dlt_list[dlt_index++] = DLT_DOCSIS;
1345 			}
1346 			if(!p->linktype)
1347 				p->linktype = DLT_EN10MB;
1348 			break;
1349 
1350 		case ERF_TYPE_ATM:
1351 		case ERF_TYPE_AAL5:
1352 		case ERF_TYPE_MC_ATM:
1353 		case ERF_TYPE_MC_AAL5:
1354 			if (p->dlt_list != NULL) {
1355 				p->dlt_list[dlt_index++] = DLT_ATM_RFC1483;
1356 				p->dlt_list[dlt_index++] = DLT_SUNATM;
1357 			}
1358 			if(!p->linktype)
1359 				p->linktype = DLT_ATM_RFC1483;
1360 			break;
1361 
1362 		case ERF_TYPE_COLOR_MC_HDLC_POS:
1363 		case ERF_TYPE_MC_HDLC:
1364 			if (p->dlt_list != NULL) {
1365 				p->dlt_list[dlt_index++] = DLT_CHDLC;
1366 				p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1367 				p->dlt_list[dlt_index++] = DLT_FRELAY;
1368 				p->dlt_list[dlt_index++] = DLT_MTP2;
1369 				p->dlt_list[dlt_index++] = DLT_MTP2_WITH_PHDR;
1370 				p->dlt_list[dlt_index++] = DLT_LAPD;
1371 			}
1372 			if(!p->linktype)
1373 				p->linktype = DLT_CHDLC;
1374 			break;
1375 
1376 		case ERF_TYPE_IPV4:
1377 			if (p->dlt_list != NULL) {
1378 				p->dlt_list[dlt_index++] = DLT_RAW;
1379 				p->dlt_list[dlt_index++] = DLT_IPV4;
1380 			}
1381 			if(!p->linktype)
1382 				p->linktype = DLT_RAW;
1383 			break;
1384 
1385 		case ERF_TYPE_IPV6:
1386 			if (p->dlt_list != NULL) {
1387 				p->dlt_list[dlt_index++] = DLT_RAW;
1388 				p->dlt_list[dlt_index++] = DLT_IPV6;
1389 			}
1390 			if(!p->linktype)
1391 				p->linktype = DLT_RAW;
1392 			break;
1393 
1394 		case ERF_TYPE_LEGACY:
1395 		case ERF_TYPE_MC_RAW:
1396 		case ERF_TYPE_MC_RAW_CHANNEL:
1397 		case ERF_TYPE_IP_COUNTER:
1398 		case ERF_TYPE_TCP_FLOW_COUNTER:
1399 		case ERF_TYPE_INFINIBAND:
1400 		case ERF_TYPE_RAW_LINK:
1401 		case ERF_TYPE_INFINIBAND_LINK:
1402 		case ERF_TYPE_META:
1403 		default:
1404 			/* Libpcap cannot deal with these types yet */
1405 			/* Add no 'native' DLTs, but still covered by DLT_ERF */
1406 			break;
1407 
1408 		} /* switch */
1409 		index++;
1410 	}
1411 
1412 	p->dlt_list[dlt_index++] = DLT_ERF;
1413 
1414 	p->dlt_count = dlt_index;
1415 
1416 	if(!p->linktype)
1417 		p->linktype = DLT_ERF;
1418 
1419 	return p->linktype;
1420 }
1421 
1422 #ifdef DAG_ONLY
1423 /*
1424  * This libpcap build supports only DAG cards, not regular network
1425  * interfaces.
1426  */
1427 
1428 /*
1429  * There are no regular interfaces, just DAG interfaces.
1430  */
1431 int
1432 pcap_platform_finddevs(pcap_if_list_t *devlistp _U_, char *errbuf)
1433 {
1434 	return (0);
1435 }
1436 
1437 /*
1438  * Attempts to open a regular interface fail.
1439  */
1440 pcap_t *
1441 pcap_create_interface(const char *device, char *errbuf)
1442 {
1443 	snprintf(errbuf, PCAP_ERRBUF_SIZE,
1444 	    "This version of libpcap only supports DAG cards");
1445 	return NULL;
1446 }
1447 
1448 /*
1449  * Libpcap version string.
1450  */
1451 const char *
1452 pcap_lib_version(void)
1453 {
1454 	return (PCAP_VERSION_STRING " (DAG-only)");
1455 }
1456 #endif
1457