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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
delete_pcap_dag(pcap_t * p)216 delete_pcap_dag(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
dag_platform_cleanup(pcap_t * p)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
atexit_handler(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
new_pcap_dag(pcap_t * p)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
dag_erf_ext_header_count(uint8_t * erf,size_t len)302 dag_erf_ext_header_count(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
dag_read(pcap_t * p,int cnt,pcap_handler callback,u_char * user)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 	/* Process the packets. */
395 	while (pd->dag_mem_top - pd->dag_mem_bottom >= dag_record_size) {
396 
397 		unsigned short packet_len = 0;
398 		int caplen = 0;
399 		struct pcap_pkthdr	pcap_header;
400 
401 		dag_record_t *header = (dag_record_t *)(pd->dag_mem_bottom);
402 
403 		u_char *dp = ((u_char *)header); /* + dag_record_size; */
404 		unsigned short rlen;
405 
406 		/*
407 		 * Has "pcap_breakloop()" been called?
408 		 */
409 		if (p->break_loop) {
410 			/*
411 			 * Yes - clear the flag that indicates that
412 			 * it has, and return -2 to indicate that
413 			 * we were told to break out of the loop.
414 			 */
415 			p->break_loop = 0;
416 			return -2;
417 		}
418 
419 		rlen = ntohs(header->rlen);
420 		if (rlen < dag_record_size)
421 		{
422 			pcap_strlcpy(p->errbuf, "dag_read: record too small",
423 			    PCAP_ERRBUF_SIZE);
424 			return -1;
425 		}
426 		pd->dag_mem_bottom += rlen;
427 
428 		/* Count lost packets. */
429 		switch((header->type & 0x7f)) {
430 			/* in these types the color value overwrites the lctr */
431 		case ERF_TYPE_COLOR_HDLC_POS:
432 		case ERF_TYPE_COLOR_ETH:
433 		case ERF_TYPE_DSM_COLOR_HDLC_POS:
434 		case ERF_TYPE_DSM_COLOR_ETH:
435 		case ERF_TYPE_COLOR_MC_HDLC_POS:
436 		case ERF_TYPE_COLOR_HASH_ETH:
437 		case ERF_TYPE_COLOR_HASH_POS:
438 			break;
439 
440 		default:
441 			if ( (pd->drop_attr == kNullAttributeUuid) && (header->lctr) ) {
442 				pd->stat.ps_drop += ntohs(header->lctr);
443 			}
444 		}
445 
446 		if ((header->type & 0x7f) == ERF_TYPE_PAD) {
447 			continue;
448 		}
449 
450 		num_ext_hdr = dag_erf_ext_header_count(dp, rlen);
451 
452 		/* ERF encapsulation */
453 		/* The Extensible Record Format is not dropped for this kind of encapsulation,
454 		 * and will be handled as a pseudo header by the decoding application.
455 		 * The information carried in the ERF header and in the optional subheader (if present)
456 		 * could be merged with the libpcap information, to offer a better decoding.
457 		 * The packet length is
458 		 * o the length of the packet on the link (header->wlen),
459 		 * o plus the length of the ERF header (dag_record_size), as the length of the
460 		 *   pseudo header will be adjusted during the decoding,
461 		 * o plus the length of the optional subheader (if present).
462 		 *
463 		 * The capture length is header.rlen and the byte stuffing for alignment will be dropped
464 		 * if the capture length is greater than the packet length.
465 		 */
466 		if (p->linktype == DLT_ERF) {
467 			packet_len = ntohs(header->wlen) + dag_record_size;
468 			caplen = rlen;
469 			switch ((header->type & 0x7f)) {
470 			case ERF_TYPE_MC_AAL5:
471 			case ERF_TYPE_MC_ATM:
472 			case ERF_TYPE_MC_HDLC:
473 			case ERF_TYPE_MC_RAW_CHANNEL:
474 			case ERF_TYPE_MC_RAW:
475 			case ERF_TYPE_MC_AAL2:
476 			case ERF_TYPE_COLOR_MC_HDLC_POS:
477 				packet_len += 4; /* MC header */
478 				break;
479 
480 			case ERF_TYPE_COLOR_HASH_ETH:
481 			case ERF_TYPE_DSM_COLOR_ETH:
482 			case ERF_TYPE_COLOR_ETH:
483 			case ERF_TYPE_ETH:
484 				packet_len += 2; /* ETH header */
485 				break;
486 			} /* switch type */
487 
488 			/* Include ERF extension headers */
489 			packet_len += (8 * num_ext_hdr);
490 
491 			if (caplen > packet_len) {
492 				caplen = packet_len;
493 			}
494 		} else {
495 			/* Other kind of encapsulation according to the header Type */
496 
497 			/* Skip over generic ERF header */
498 			dp += dag_record_size;
499 			/* Skip over extension headers */
500 			dp += 8 * num_ext_hdr;
501 
502 			switch((header->type & 0x7f)) {
503 			case ERF_TYPE_ATM:
504 			case ERF_TYPE_AAL5:
505 				if ((header->type & 0x7f) == ERF_TYPE_AAL5) {
506 					packet_len = ntohs(header->wlen);
507 					caplen = rlen - dag_record_size;
508 				}
509 			case ERF_TYPE_MC_ATM:
510 				if ((header->type & 0x7f) == ERF_TYPE_MC_ATM) {
511 					caplen = packet_len = ATM_CELL_SIZE;
512 					dp+=4;
513 				}
514 			case ERF_TYPE_MC_AAL5:
515 				if ((header->type & 0x7f) == ERF_TYPE_MC_AAL5) {
516 					packet_len = ntohs(header->wlen);
517 					caplen = rlen - dag_record_size - 4;
518 					dp+=4;
519 				}
520 				/* Skip over extension headers */
521 				caplen -= (8 * num_ext_hdr);
522 
523 				if ((header->type & 0x7f) == ERF_TYPE_ATM) {
524 					caplen = packet_len = ATM_CELL_SIZE;
525 				}
526 				if (p->linktype == DLT_SUNATM) {
527 					struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
528 					unsigned long rawatm;
529 
530 					rawatm = ntohl(*((unsigned long *)dp));
531 					sunatm->vci = htons((rawatm >>  4) & 0xffff);
532 					sunatm->vpi = (rawatm >> 20) & 0x00ff;
533 					sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) |
534 						((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
535 						 ((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 :
536 						  ((dp[ATM_HDR_SIZE] == 0xaa &&
537 						    dp[ATM_HDR_SIZE+1] == 0xaa &&
538 						    dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
539 
540 				} else if (p->linktype == DLT_ATM_RFC1483) {
541 					packet_len -= ATM_HDR_SIZE;
542 					caplen -= ATM_HDR_SIZE;
543 					dp += ATM_HDR_SIZE;
544 				} else
545 					continue;
546 				break;
547 
548 			case ERF_TYPE_COLOR_HASH_ETH:
549 			case ERF_TYPE_DSM_COLOR_ETH:
550 			case ERF_TYPE_COLOR_ETH:
551 			case ERF_TYPE_ETH:
552 				if ((p->linktype != DLT_EN10MB) &&
553 				    (p->linktype != DLT_DOCSIS))
554 					continue;
555 				packet_len = ntohs(header->wlen);
556 				packet_len -= (pd->dag_fcs_bits >> 3);
557 				caplen = rlen - dag_record_size - 2;
558 				/* Skip over extension headers */
559 				caplen -= (8 * num_ext_hdr);
560 				if (caplen > packet_len) {
561 					caplen = packet_len;
562 				}
563 				dp += 2;
564 				break;
565 
566 			case ERF_TYPE_COLOR_HASH_POS:
567 			case ERF_TYPE_DSM_COLOR_HDLC_POS:
568 			case ERF_TYPE_COLOR_HDLC_POS:
569 			case ERF_TYPE_HDLC_POS:
570 				if ((p->linktype != DLT_CHDLC) &&
571 				    (p->linktype != DLT_PPP_SERIAL) &&
572 				    (p->linktype != DLT_FRELAY))
573 					continue;
574 				packet_len = ntohs(header->wlen);
575 				packet_len -= (pd->dag_fcs_bits >> 3);
576 				caplen = rlen - dag_record_size;
577 				/* Skip over extension headers */
578 				caplen -= (8 * num_ext_hdr);
579 				if (caplen > packet_len) {
580 					caplen = packet_len;
581 				}
582 				break;
583 
584 			case ERF_TYPE_COLOR_MC_HDLC_POS:
585 			case ERF_TYPE_MC_HDLC:
586 				if ((p->linktype != DLT_CHDLC) &&
587 				    (p->linktype != DLT_PPP_SERIAL) &&
588 				    (p->linktype != DLT_FRELAY) &&
589 				    (p->linktype != DLT_MTP2) &&
590 				    (p->linktype != DLT_MTP2_WITH_PHDR) &&
591 				    (p->linktype != DLT_LAPD))
592 					continue;
593 				packet_len = ntohs(header->wlen);
594 				packet_len -= (pd->dag_fcs_bits >> 3);
595 				caplen = rlen - dag_record_size - 4;
596 				/* Skip over extension headers */
597 				caplen -= (8 * num_ext_hdr);
598 				if (caplen > packet_len) {
599 					caplen = packet_len;
600 				}
601 				/* jump the MC_HDLC_HEADER */
602 				dp += 4;
603 #ifdef DLT_MTP2_WITH_PHDR
604 				if (p->linktype == DLT_MTP2_WITH_PHDR) {
605 					/* Add the MTP2 Pseudo Header */
606 					caplen += MTP2_HDR_LEN;
607 					packet_len += MTP2_HDR_LEN;
608 
609 					TempPkt[MTP2_SENT_OFFSET] = 0;
610 					TempPkt[MTP2_ANNEX_A_USED_OFFSET] = MTP2_ANNEX_A_USED_UNKNOWN;
611 					*(TempPkt+MTP2_LINK_NUMBER_OFFSET) = ((header->rec.mc_hdlc.mc_header>>16)&0x01);
612 					*(TempPkt+MTP2_LINK_NUMBER_OFFSET+1) = ((header->rec.mc_hdlc.mc_header>>24)&0xff);
613 					memcpy(TempPkt+MTP2_HDR_LEN, dp, caplen);
614 					dp = TempPkt;
615 				}
616 #endif
617 				break;
618 
619 			case ERF_TYPE_IPV4:
620 				if ((p->linktype != DLT_RAW) &&
621 				    (p->linktype != DLT_IPV4))
622 					continue;
623 				packet_len = ntohs(header->wlen);
624 				caplen = rlen - dag_record_size;
625 				/* Skip over extension headers */
626 				caplen -= (8 * num_ext_hdr);
627 				if (caplen > packet_len) {
628 					caplen = packet_len;
629 				}
630 				break;
631 
632 			case ERF_TYPE_IPV6:
633 				if ((p->linktype != DLT_RAW) &&
634 				    (p->linktype != DLT_IPV6))
635 					continue;
636 				packet_len = ntohs(header->wlen);
637 				caplen = rlen - dag_record_size;
638 				/* Skip over extension headers */
639 				caplen -= (8 * num_ext_hdr);
640 				if (caplen > packet_len) {
641 					caplen = packet_len;
642 				}
643 				break;
644 
645 			/* These types have no matching 'native' DLT, but can be used with DLT_ERF above */
646 			case ERF_TYPE_MC_RAW:
647 			case ERF_TYPE_MC_RAW_CHANNEL:
648 			case ERF_TYPE_IP_COUNTER:
649 			case ERF_TYPE_TCP_FLOW_COUNTER:
650 			case ERF_TYPE_INFINIBAND:
651 			case ERF_TYPE_RAW_LINK:
652 			case ERF_TYPE_INFINIBAND_LINK:
653 			default:
654 				/* Unhandled ERF type.
655 				 * Ignore rather than generating error
656 				 */
657 				continue;
658 			} /* switch type */
659 
660 		} /* ERF encapsulation */
661 
662 		if (caplen > p->snapshot)
663 			caplen = p->snapshot;
664 
665 		/* Run the packet filter if there is one. */
666 		if ((p->fcode.bf_insns == NULL) || pcap_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
667 
668 			/* convert between timestamp formats */
669 			register unsigned long long ts;
670 
671 			if (IS_BIGENDIAN()) {
672 				ts = SWAPLL(header->ts);
673 			} else {
674 				ts = header->ts;
675 			}
676 
677 			switch (p->opt.tstamp_precision) {
678 			case PCAP_TSTAMP_PRECISION_NANO:
679 				ticks_per_second = 1000000000;
680 				break;
681 			case PCAP_TSTAMP_PRECISION_MICRO:
682 			default:
683 				ticks_per_second = 1000000;
684 				break;
685 
686 			}
687 			pcap_header.ts.tv_sec = ts >> 32;
688 			ts = (ts & 0xffffffffULL) * ticks_per_second;
689 			ts += 0x80000000; /* rounding */
690 			pcap_header.ts.tv_usec = ts >> 32;
691 			if (pcap_header.ts.tv_usec >= ticks_per_second) {
692 				pcap_header.ts.tv_usec -= ticks_per_second;
693 				pcap_header.ts.tv_sec++;
694 			}
695 
696 			/* Fill in our own header data */
697 			pcap_header.caplen = caplen;
698 			pcap_header.len = packet_len;
699 
700 			/* Count the packet. */
701 			pd->stat.ps_recv++;
702 
703 			/* Call the user supplied callback function */
704 			callback(user, &pcap_header, dp);
705 
706 			/* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
707 			processed++;
708 			if (processed == cnt && !PACKET_COUNT_IS_UNLIMITED(cnt))
709 			{
710 				/* Reached the user-specified limit. */
711 				return cnt;
712 			}
713 		}
714 	}
715 
716 	return processed;
717 }
718 
719 static int
dag_inject(pcap_t * p,const void * buf _U_,int size _U_)720 dag_inject(pcap_t *p, const void *buf _U_, int size _U_)
721 {
722 	pcap_strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
723 	    PCAP_ERRBUF_SIZE);
724 	return (-1);
725 }
726 
727 /*
728  *  Get a handle for a live capture from the given DAG device.  Passing a NULL
729  *  device will result in a failure.  The promisc flag is ignored because DAG
730  *  cards are always promiscuous.  The to_ms parameter is used in setting the
731  *  API polling parameters.
732  *
733  *  snaplen is now also ignored, until we get per-stream slen support. Set
734  *  slen with approprite DAG tool BEFORE pcap_activate().
735  *
736  *  See also pcap(3).
737  */
dag_activate(pcap_t * p)738 static int dag_activate(pcap_t* p)
739 {
740 	struct pcap_dag *pd = p->priv;
741 	char *s;
742 	int n;
743 	daginf_t* daginf;
744 	char * newDev = NULL;
745 	char * device = p->opt.device;
746 	int ret;
747 	dag_size_t mindata;
748 	struct timeval maxwait;
749 	struct timeval poll;
750 
751 	if (device == NULL) {
752 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "device is NULL");
753 		return PCAP_ERROR;
754 	}
755 
756 	/* Initialize some components of the pcap structure. */
757 	newDev = (char *)malloc(strlen(device) + 16);
758 	if (newDev == NULL) {
759 		ret = PCAP_ERROR;
760 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
761 		    errno, "Can't allocate string for device name");
762 		goto fail;
763 	}
764 
765 	/* Parse input name to get dag device and stream number if provided */
766 	if (dag_parse_name(device, newDev, strlen(device) + 16, &pd->dag_stream) < 0) {
767 		/*
768 		 * XXX - it'd be nice if this indicated what was wrong
769 		 * with the name.  Does this reliably set errno?
770 		 * Should this return PCAP_ERROR_NO_SUCH_DEVICE in some
771 		 * cases?
772 		 */
773 		ret = PCAP_ERROR;
774 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
775 		    errno, "dag_parse_name");
776 		goto fail;
777 	}
778 	device = newDev;
779 
780 	if (pd->dag_stream%2) {
781 		ret = PCAP_ERROR;
782 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: tx (even numbered) streams not supported for capture");
783 		goto fail;
784 	}
785 
786 	/* setup device parameters */
787 	if((pd->dag_ref = dag_config_init((char *)device)) == NULL) {
788 		/*
789 		 * XXX - does this reliably set errno?
790 		 */
791 		if (errno == ENOENT)
792 			ret = PCAP_ERROR_NO_SUCH_DEVICE;
793 		else if (errno == EPERM || errno == EACCES)
794 			ret = PCAP_ERROR_PERM_DENIED;
795 		else
796 			ret = PCAP_ERROR;
797 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
798 		    errno, "dag_config_init %s", device);
799 		goto fail;
800 	}
801 
802 	if((p->fd = dag_config_get_card_fd(pd->dag_ref)) < 0) {
803 		/*
804 		 * XXX - does this reliably set errno?
805 		 */
806 		ret = PCAP_ERROR;
807 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
808 		    errno, "dag_config_get_card_fd %s", device);
809 		goto failclose;
810 	}
811 
812 	/* Open requested stream. Can fail if already locked or on error */
813 	if (dag_attach_stream64(p->fd, pd->dag_stream, 0, 0) < 0) {
814 		ret = PCAP_ERROR;
815 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
816 		    errno, "dag_attach_stream");
817 		goto failclose;
818 	}
819 
820 	/* Try to find Stream Drop attribute */
821 	pd->drop_attr = kNullAttributeUuid;
822 	pd->dag_root = dag_config_get_root_component(pd->dag_ref);
823 	if ( dag_component_get_subcomponent(pd->dag_root, kComponentStreamFeatures, 0) )
824 	{
825 		pd->drop_attr = dag_config_get_indexed_attribute_uuid(pd->dag_ref, kUint32AttributeStreamDropCount, pd->dag_stream/2);
826 	}
827 
828 	/* Set up default poll parameters for stream
829 	 * Can be overridden by pcap_set_nonblock()
830 	 */
831 	if (dag_get_stream_poll64(p->fd, pd->dag_stream,
832 				&mindata, &maxwait, &poll) < 0) {
833 		ret = PCAP_ERROR;
834 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
835 		    errno, "dag_get_stream_poll");
836 		goto faildetach;
837 	}
838 
839 	/* Use the poll time as the required select timeout for callers
840 	 * who are using select()/etc. in an event loop waiting for
841 	 * packets to arrive.
842 	 */
843 	pd->required_select_timeout = poll;
844 	p->required_select_timeout = &pd->required_select_timeout;
845 
846 	/*
847 	 * Turn a negative snapshot value (invalid), a snapshot value of
848 	 * 0 (unspecified), or a value bigger than the normal maximum
849 	 * value, into the maximum allowed value.
850 	 *
851 	 * If some application really *needs* a bigger snapshot
852 	 * length, we should just increase MAXIMUM_SNAPLEN.
853 	 */
854 	if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
855 		p->snapshot = MAXIMUM_SNAPLEN;
856 
857 	if (p->opt.immediate) {
858 		/* Call callback immediately.
859 		 * XXX - is this the right way to p this?
860 		 */
861 		mindata = 0;
862 	} else {
863 		/* Amount of data to collect in Bytes before calling callbacks.
864 		 * Important for efficiency, but can introduce latency
865 		 * at low packet rates if to_ms not set!
866 		 */
867 		mindata = 65536;
868 	}
869 
870 	/* Obey opt.timeout (was to_ms) if supplied. This is a good idea!
871 	 * Recommend 10-100ms. Calls will time out even if no data arrived.
872 	 */
873 	maxwait.tv_sec = p->opt.timeout/1000;
874 	maxwait.tv_usec = (p->opt.timeout%1000) * 1000;
875 
876 	if (dag_set_stream_poll64(p->fd, pd->dag_stream,
877 				mindata, &maxwait, &poll) < 0) {
878 		ret = PCAP_ERROR;
879 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
880 		    errno, "dag_set_stream_poll");
881 		goto faildetach;
882 	}
883 
884         /* XXX Not calling dag_configure() to set slen; this is unsafe in
885 	 * multi-stream environments as the gpp config is global.
886          * Once the firmware provides 'per-stream slen' this can be supported
887 	 * again via the Config API without side-effects */
888 #if 0
889 	/* set the card snap length to the specified snaplen parameter */
890 	/* This is a really bad idea, as different cards have different
891 	 * valid slen ranges. Should fix in Config API. */
892 	if (p->snapshot == 0 || p->snapshot > MAX_DAG_SNAPLEN) {
893 		p->snapshot = MAX_DAG_SNAPLEN;
894 	} else if (snaplen < MIN_DAG_SNAPLEN) {
895 		p->snapshot = MIN_DAG_SNAPLEN;
896 	}
897 	/* snap len has to be a multiple of 4 */
898 #endif
899 
900 	if(dag_start_stream(p->fd, pd->dag_stream) < 0) {
901 		ret = PCAP_ERROR;
902 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
903 		    errno, "dag_start_stream %s", device);
904 		goto faildetach;
905 	}
906 
907 	/*
908 	 * Important! You have to ensure bottom is properly
909 	 * initialized to zero on startup, it won't give you
910 	 * a compiler warning if you make this mistake!
911 	 */
912 	pd->dag_mem_bottom = 0;
913 	pd->dag_mem_top = 0;
914 
915 	/*
916 	 * Find out how many FCS bits we should strip.
917 	 * First, query the card to see if it strips the FCS.
918 	 */
919 	daginf = dag_info(p->fd);
920 	if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code))	{
921 		/* DAG 4.2S and 4.23S already strip the FCS.  Stripping the final word again truncates the packet. */
922 		pd->dag_fcs_bits = 0;
923 
924 		/* Note that no FCS will be supplied. */
925 		p->linktype_ext = LT_FCS_DATALINK_EXT(0);
926 	} else {
927 		/*
928 		 * Start out assuming it's 32 bits.
929 		 */
930 		pd->dag_fcs_bits = 32;
931 
932 		/* Allow an environment variable to override. */
933 		if ((s = getenv("ERF_FCS_BITS")) != NULL) {
934 			if ((n = atoi(s)) == 0 || n == 16 || n == 32) {
935 				pd->dag_fcs_bits = n;
936 			} else {
937 				ret = PCAP_ERROR;
938 				snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
939 					"pcap_activate %s: bad ERF_FCS_BITS value (%d) in environment", device, n);
940 				goto failstop;
941 			}
942 		}
943 
944 		/*
945 		 * Did the user request that they not be stripped?
946 		 */
947 		if ((s = getenv("ERF_DONT_STRIP_FCS")) != NULL) {
948 			/* Yes.  Note the number of bytes that will be
949 			   supplied. */
950 			p->linktype_ext = LT_FCS_DATALINK_EXT(pd->dag_fcs_bits/16);
951 
952 			/* And don't strip them. */
953 			pd->dag_fcs_bits = 0;
954 		}
955 	}
956 
957 	pd->dag_timeout	= p->opt.timeout;
958 
959 	p->linktype = -1;
960 	if (dag_get_datalink(p) < 0) {
961 		ret = PCAP_ERROR;
962 		goto failstop;
963 	}
964 
965 	p->bufsize = 0;
966 
967 	if (new_pcap_dag(p) < 0) {
968 		ret = PCAP_ERROR;
969 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
970 		    errno, "new_pcap_dag %s", device);
971 		goto failstop;
972 	}
973 
974 	/*
975 	 * "select()" and "poll()" don't work on DAG device descriptors.
976 	 */
977 	p->selectable_fd = -1;
978 
979 	if (newDev != NULL) {
980 		free((char *)newDev);
981 	}
982 
983 	p->read_op = dag_read;
984 	p->inject_op = dag_inject;
985 	p->setfilter_op = install_bpf_program;
986 	p->setdirection_op = NULL; /* Not implemented.*/
987 	p->set_datalink_op = dag_set_datalink;
988 	p->getnonblock_op = pcap_getnonblock_fd;
989 	p->setnonblock_op = dag_setnonblock;
990 	p->stats_op = dag_stats;
991 	p->cleanup_op = dag_platform_cleanup;
992 	pd->stat.ps_drop = 0;
993 	pd->stat.ps_recv = 0;
994 	pd->stat.ps_ifdrop = 0;
995 	return 0;
996 
997 failstop:
998 	if (dag_stop_stream(p->fd, pd->dag_stream) < 0) {
999 		fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
1000 	}
1001 
1002 faildetach:
1003 	if (dag_detach_stream(p->fd, pd->dag_stream) < 0)
1004 		fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
1005 
1006 failclose:
1007 	dag_config_dispose(pd->dag_ref);
1008 	/*
1009 	 * Note: we don't need to call close(p->fd) or dag_close(p->fd),
1010 	 * as dag_config_dispose(pd->dag_ref) does this.
1011 	 *
1012 	 * Set p->fd to -1 to make sure that's not done.
1013 	 */
1014 	p->fd = -1;
1015 	pd->dag_ref = NULL;
1016 	delete_pcap_dag(p);
1017 
1018 fail:
1019 	pcap_cleanup_live_common(p);
1020 	if (newDev != NULL) {
1021 		free((char *)newDev);
1022 	}
1023 
1024 	return ret;
1025 }
1026 
dag_create(const char * device,char * ebuf,int * is_ours)1027 pcap_t *dag_create(const char *device, char *ebuf, int *is_ours)
1028 {
1029 	const char *cp;
1030 	char *cpend;
1031 	long devnum;
1032 	pcap_t *p;
1033 	long stream = 0;
1034 
1035 	/* Does this look like a DAG device? */
1036 	cp = strrchr(device, '/');
1037 	if (cp == NULL)
1038 		cp = device;
1039 	/* Does it begin with "dag"? */
1040 	if (strncmp(cp, "dag", 3) != 0) {
1041 		/* Nope, doesn't begin with "dag" */
1042 		*is_ours = 0;
1043 		return NULL;
1044 	}
1045 	/* Yes - is "dag" followed by a number from 0 to DAG_MAX_BOARDS-1 */
1046 	cp += 3;
1047 	devnum = strtol(cp, &cpend, 10);
1048 	if (*cpend == ':') {
1049 		/* Followed by a stream number. */
1050 		stream = strtol(++cpend, &cpend, 10);
1051 	}
1052 
1053 	if (cpend == cp || *cpend != '\0') {
1054 		/* Not followed by a number. */
1055 		*is_ours = 0;
1056 		return NULL;
1057 	}
1058 
1059 	if (devnum < 0 || devnum >= DAG_MAX_BOARDS) {
1060 		/* Followed by a non-valid number. */
1061 		*is_ours = 0;
1062 		return NULL;
1063 	}
1064 
1065 	if (stream <0 || stream >= DAG_STREAM_MAX) {
1066 		/* Followed by a non-valid stream number. */
1067 		*is_ours = 0;
1068 		return NULL;
1069 	}
1070 
1071 	/* OK, it's probably ours. */
1072 	*is_ours = 1;
1073 
1074 	p = PCAP_CREATE_COMMON(ebuf, struct pcap_dag);
1075 	if (p == NULL)
1076 		return NULL;
1077 
1078 	p->activate_op = dag_activate;
1079 
1080 	/*
1081 	 * We claim that we support microsecond and nanosecond time
1082 	 * stamps.
1083 	 *
1084 	 * XXX Our native precision is 2^-32s, but libpcap doesn't support
1085 	 * power of two precisions yet. We can convert to either MICRO or NANO.
1086 	 */
1087 	p->tstamp_precision_list = malloc(2 * sizeof(u_int));
1088 	if (p->tstamp_precision_list == NULL) {
1089 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1090 		    errno, "malloc");
1091 		pcap_close(p);
1092 		return NULL;
1093 	}
1094 	p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
1095 	p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
1096 	p->tstamp_precision_count = 2;
1097 	return p;
1098 }
1099 
1100 static int
dag_stats(pcap_t * p,struct pcap_stat * ps)1101 dag_stats(pcap_t *p, struct pcap_stat *ps) {
1102 	struct pcap_dag *pd = p->priv;
1103 	uint32_t stream_drop;
1104 	dag_err_t dag_error;
1105 
1106 	/*
1107 	 * Packet records received (ps_recv) are counted in dag_read().
1108 	 * Packet records dropped (ps_drop) are read from Stream Drop attribute if present,
1109 	 * otherwise integrate the ERF Header lctr counts (if available) in dag_read().
1110 	 * We are reporting that no records are dropped by the card/driver (ps_ifdrop).
1111 	 */
1112 
1113 	if(pd->drop_attr != kNullAttributeUuid) {
1114 		/* Note this counter is cleared at start of capture and will wrap at UINT_MAX.
1115 		 * The application is responsible for polling ps_drop frequently enough
1116 		 * to detect each wrap and integrate total drop with a wider counter */
1117 		if ((dag_error = dag_config_get_uint32_attribute_ex(pd->dag_ref, pd->drop_attr, &stream_drop)) == kDagErrNone) {
1118 			pd->stat.ps_drop = stream_drop;
1119 		} else {
1120 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "reading stream drop attribute: %s",
1121 				 dag_config_strerror(dag_error));
1122 			return -1;
1123 		}
1124 	}
1125 
1126 	*ps = pd->stat;
1127 
1128 	return 0;
1129 }
1130 
1131 /*
1132  * Add all DAG devices.
1133  */
1134 int
dag_findalldevs(pcap_if_list_t * devlistp,char * errbuf)1135 dag_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
1136 {
1137 	char name[12];	/* XXX - pick a size */
1138 	int c;
1139 	char dagname[DAGNAME_BUFSIZE];
1140 	int dagstream;
1141 	int dagfd;
1142 	dag_card_inf_t *inf;
1143 	char *description;
1144 	int stream, rxstreams;
1145 
1146 	/* Try all the DAGs 0-DAG_MAX_BOARDS */
1147 	for (c = 0; c < DAG_MAX_BOARDS; c++) {
1148 		snprintf(name, 12, "dag%d", c);
1149 		if (-1 == dag_parse_name(name, dagname, DAGNAME_BUFSIZE, &dagstream))
1150 		{
1151 			(void) snprintf(errbuf, PCAP_ERRBUF_SIZE,
1152 			    "dag: device name %s can't be parsed", name);
1153 			return (-1);
1154 		}
1155 		if ( (dagfd = dag_open(dagname)) >= 0 ) {
1156 			description = NULL;
1157 			if ((inf = dag_pciinfo(dagfd)))
1158 				description = dag_device_name(inf->device_code, 1);
1159 			/*
1160 			 * XXX - is there a way to determine whether
1161 			 * the card is plugged into a network or not?
1162 			 * If so, we should check that and set
1163 			 * PCAP_IF_CONNECTION_STATUS_CONNECTED or
1164 			 * PCAP_IF_CONNECTION_STATUS_DISCONNECTED.
1165 			 *
1166 			 * Also, are there notions of "up" and "running"?
1167 			 */
1168 			if (add_dev(devlistp, name, 0, description, errbuf) == NULL) {
1169 				/*
1170 				 * Failure.
1171 				 */
1172 				return (-1);
1173 			}
1174 			rxstreams = dag_rx_get_stream_count(dagfd);
1175 			for(stream=0;stream<DAG_STREAM_MAX;stream+=2) {
1176 				if (0 == dag_attach_stream64(dagfd, stream, 0, 0)) {
1177 					dag_detach_stream(dagfd, stream);
1178 
1179 					snprintf(name,  10, "dag%d:%d", c, stream);
1180 					if (add_dev(devlistp, name, 0, description, errbuf) == NULL) {
1181 						/*
1182 						 * Failure.
1183 						 */
1184 						return (-1);
1185 					}
1186 
1187 					rxstreams--;
1188 					if(rxstreams <= 0) {
1189 						break;
1190 					}
1191 				}
1192 			}
1193 			dag_close(dagfd);
1194 		}
1195 
1196 	}
1197 	return (0);
1198 }
1199 
1200 static int
dag_set_datalink(pcap_t * p,int dlt)1201 dag_set_datalink(pcap_t *p, int dlt)
1202 {
1203 	p->linktype = dlt;
1204 
1205 	return (0);
1206 }
1207 
1208 static int
dag_setnonblock(pcap_t * p,int nonblock)1209 dag_setnonblock(pcap_t *p, int nonblock)
1210 {
1211 	struct pcap_dag *pd = p->priv;
1212 	dag_size_t mindata;
1213 	struct timeval maxwait;
1214 	struct timeval poll;
1215 
1216 	/*
1217 	 * Set non-blocking mode on the FD.
1218 	 * XXX - is that necessary?  If not, don't bother calling it,
1219 	 * and have a "dag_getnonblock()" function that looks at
1220 	 * "pd->dag_flags".
1221 	 */
1222 	if (pcap_setnonblock_fd(p, nonblock) < 0)
1223 		return (-1);
1224 
1225 	if (dag_get_stream_poll64(p->fd, pd->dag_stream,
1226 				&mindata, &maxwait, &poll) < 0) {
1227 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
1228 		    errno, "dag_get_stream_poll");
1229 		return -1;
1230 	}
1231 
1232 	/* Amount of data to collect in Bytes before calling callbacks.
1233 	 * Important for efficiency, but can introduce latency
1234 	 * at low packet rates if to_ms not set!
1235 	 */
1236 	if(nonblock)
1237 		mindata = 0;
1238 	else
1239 		mindata = 65536;
1240 
1241 	if (dag_set_stream_poll64(p->fd, pd->dag_stream,
1242 				mindata, &maxwait, &poll) < 0) {
1243 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
1244 		    errno, "dag_set_stream_poll");
1245 		return -1;
1246 	}
1247 
1248 	if (nonblock) {
1249 		pd->dag_flags |= DAGF_NONBLOCK;
1250 	} else {
1251 		pd->dag_flags &= ~DAGF_NONBLOCK;
1252 	}
1253 	return (0);
1254 }
1255 
1256 static int
dag_get_datalink(pcap_t * p)1257 dag_get_datalink(pcap_t *p)
1258 {
1259 	struct pcap_dag *pd = p->priv;
1260 	int index=0, dlt_index=0;
1261 	uint8_t types[255];
1262 
1263 	memset(types, 0, 255);
1264 
1265 	if (p->dlt_list == NULL && (p->dlt_list = malloc(255*sizeof(*(p->dlt_list)))) == NULL) {
1266 		pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
1267 		    errno, "malloc");
1268 		return (-1);
1269 	}
1270 
1271 	p->linktype = 0;
1272 
1273 #ifdef HAVE_DAG_GET_STREAM_ERF_TYPES
1274 	/* Get list of possible ERF types for this card */
1275 	if (dag_get_stream_erf_types(p->fd, pd->dag_stream, types, 255) < 0) {
1276 		pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
1277 		    errno, "dag_get_stream_erf_types");
1278 		return (-1);
1279 	}
1280 
1281 	while (types[index]) {
1282 
1283 #elif defined HAVE_DAG_GET_ERF_TYPES
1284 	/* Get list of possible ERF types for this card */
1285 	if (dag_get_erf_types(p->fd, types, 255) < 0) {
1286 		pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
1287 		    errno, "dag_get_erf_types");
1288 		return (-1);
1289 	}
1290 
1291 	while (types[index]) {
1292 #else
1293 	/* Check the type through a dagapi call. */
1294 	types[index] = dag_linktype(p->fd);
1295 
1296 	{
1297 #endif
1298 		switch((types[index] & 0x7f)) {
1299 
1300 		case ERF_TYPE_HDLC_POS:
1301 		case ERF_TYPE_COLOR_HDLC_POS:
1302 		case ERF_TYPE_DSM_COLOR_HDLC_POS:
1303 		case ERF_TYPE_COLOR_HASH_POS:
1304 
1305 			if (p->dlt_list != NULL) {
1306 				p->dlt_list[dlt_index++] = DLT_CHDLC;
1307 				p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1308 				p->dlt_list[dlt_index++] = DLT_FRELAY;
1309 			}
1310 			if(!p->linktype)
1311 				p->linktype = DLT_CHDLC;
1312 			break;
1313 
1314 		case ERF_TYPE_ETH:
1315 		case ERF_TYPE_COLOR_ETH:
1316 		case ERF_TYPE_DSM_COLOR_ETH:
1317 		case ERF_TYPE_COLOR_HASH_ETH:
1318 			/*
1319 			 * This is (presumably) a real Ethernet capture; give it a
1320 			 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
1321 			 * that an application can let you choose it, in case you're
1322 			 * capturing DOCSIS traffic that a Cisco Cable Modem
1323 			 * Termination System is putting out onto an Ethernet (it
1324 			 * doesn't put an Ethernet header onto the wire, it puts raw
1325 			 * DOCSIS frames out on the wire inside the low-level
1326 			 * Ethernet framing).
1327 			 */
1328 			if (p->dlt_list != NULL) {
1329 				p->dlt_list[dlt_index++] = DLT_EN10MB;
1330 				p->dlt_list[dlt_index++] = DLT_DOCSIS;
1331 			}
1332 			if(!p->linktype)
1333 				p->linktype = DLT_EN10MB;
1334 			break;
1335 
1336 		case ERF_TYPE_ATM:
1337 		case ERF_TYPE_AAL5:
1338 		case ERF_TYPE_MC_ATM:
1339 		case ERF_TYPE_MC_AAL5:
1340 			if (p->dlt_list != NULL) {
1341 				p->dlt_list[dlt_index++] = DLT_ATM_RFC1483;
1342 				p->dlt_list[dlt_index++] = DLT_SUNATM;
1343 			}
1344 			if(!p->linktype)
1345 				p->linktype = DLT_ATM_RFC1483;
1346 			break;
1347 
1348 		case ERF_TYPE_COLOR_MC_HDLC_POS:
1349 		case ERF_TYPE_MC_HDLC:
1350 			if (p->dlt_list != NULL) {
1351 				p->dlt_list[dlt_index++] = DLT_CHDLC;
1352 				p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1353 				p->dlt_list[dlt_index++] = DLT_FRELAY;
1354 				p->dlt_list[dlt_index++] = DLT_MTP2;
1355 				p->dlt_list[dlt_index++] = DLT_MTP2_WITH_PHDR;
1356 				p->dlt_list[dlt_index++] = DLT_LAPD;
1357 			}
1358 			if(!p->linktype)
1359 				p->linktype = DLT_CHDLC;
1360 			break;
1361 
1362 		case ERF_TYPE_IPV4:
1363 			if (p->dlt_list != NULL) {
1364 				p->dlt_list[dlt_index++] = DLT_RAW;
1365 				p->dlt_list[dlt_index++] = DLT_IPV4;
1366 			}
1367 			if(!p->linktype)
1368 				p->linktype = DLT_RAW;
1369 			break;
1370 
1371 		case ERF_TYPE_IPV6:
1372 			if (p->dlt_list != NULL) {
1373 				p->dlt_list[dlt_index++] = DLT_RAW;
1374 				p->dlt_list[dlt_index++] = DLT_IPV6;
1375 			}
1376 			if(!p->linktype)
1377 				p->linktype = DLT_RAW;
1378 			break;
1379 
1380 		case ERF_TYPE_LEGACY:
1381 		case ERF_TYPE_MC_RAW:
1382 		case ERF_TYPE_MC_RAW_CHANNEL:
1383 		case ERF_TYPE_IP_COUNTER:
1384 		case ERF_TYPE_TCP_FLOW_COUNTER:
1385 		case ERF_TYPE_INFINIBAND:
1386 		case ERF_TYPE_RAW_LINK:
1387 		case ERF_TYPE_INFINIBAND_LINK:
1388 		case ERF_TYPE_META:
1389 		default:
1390 			/* Libpcap cannot deal with these types yet */
1391 			/* Add no 'native' DLTs, but still covered by DLT_ERF */
1392 			break;
1393 
1394 		} /* switch */
1395 		index++;
1396 	}
1397 
1398 	p->dlt_list[dlt_index++] = DLT_ERF;
1399 
1400 	p->dlt_count = dlt_index;
1401 
1402 	if(!p->linktype)
1403 		p->linktype = DLT_ERF;
1404 
1405 	return p->linktype;
1406 }
1407 
1408 #ifdef DAG_ONLY
1409 /*
1410  * This libpcap build supports only DAG cards, not regular network
1411  * interfaces.
1412  */
1413 
1414 /*
1415  * There are no regular interfaces, just DAG interfaces.
1416  */
1417 int
1418 pcap_platform_finddevs(pcap_if_list_t *devlistp _U_, char *errbuf)
1419 {
1420 	return (0);
1421 }
1422 
1423 /*
1424  * Attempts to open a regular interface fail.
1425  */
1426 pcap_t *
1427 pcap_create_interface(const char *device, char *errbuf)
1428 {
1429 	snprintf(errbuf, PCAP_ERRBUF_SIZE,
1430 	    "This version of libpcap only supports DAG cards");
1431 	return NULL;
1432 }
1433 
1434 /*
1435  * Libpcap version string.
1436  */
1437 const char *
1438 pcap_lib_version(void)
1439 {
1440 	return (PCAP_VERSION_STRING " (DAG-only)");
1441 }
1442 #endif
1443