1 /*
2 * pcap-dag.c: Packet capture interface for Endace DAG card.
3 *
4 * The functionality of this code attempts to mimic that of pcap-linux as much
5 * as possible. This code is compiled in several different ways depending on
6 * whether DAG_ONLY and HAVE_DAG_API are defined. If HAVE_DAG_API is not
7 * defined it should not get compiled in, otherwise if DAG_ONLY is defined then
8 * the 'dag_' function calls are renamed to 'pcap_' equivalents. If DAG_ONLY
9 * is not defined then nothing is altered - the dag_ functions will be
10 * called as required from their pcap-linux/bpf equivalents.
11 *
12 * Authors: Richard Littin, Sean Irvine ({richard,sean}@reeltwo.com)
13 * Modifications: Jesper Peterson <support@endace.com>
14 * Koryn Grant <support@endace.com>
15 * Stephen Donnelly <support@endace.com>
16 */
17
18 #ifndef lint
19 static const char rcsid[] _U_ =
20 "@(#) $Header: /tcpdump/master/libpcap/pcap-dag.c,v 1.39 2008-04-14 20:40:58 guy Exp $ (LBL)";
21 #endif
22
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26
27 #include <sys/param.h> /* optionally get BSD define */
28
29 #include <stdlib.h>
30 #include <string.h>
31 #include <errno.h>
32
33 #include "pcap-int.h"
34
35 #include <ctype.h>
36 #include <netinet/in.h>
37 #include <sys/mman.h>
38 #include <sys/socket.h>
39 #include <sys/types.h>
40 #include <unistd.h>
41
42 struct mbuf; /* Squelch compiler warnings on some platforms for */
43 struct rtentry; /* declarations in <net/if.h> */
44 #include <net/if.h>
45
46 #include "dagnew.h"
47 #include "dagapi.h"
48
49 #include "pcap-dag.h"
50
51 /*
52 * DAG devices have names beginning with "dag", followed by a number
53 * from 0 to DAG_MAX_BOARDS, then optionally a colon and a stream number
54 * from 0 to DAG_STREAM_MAX.
55 */
56 #ifndef DAG_MAX_BOARDS
57 #define DAG_MAX_BOARDS 32
58 #endif
59
60 #define ATM_CELL_SIZE 52
61 #define ATM_HDR_SIZE 4
62
63 /*
64 * A header containing additional MTP information.
65 */
66 #define MTP2_SENT_OFFSET 0 /* 1 byte */
67 #define MTP2_ANNEX_A_USED_OFFSET 1 /* 1 byte */
68 #define MTP2_LINK_NUMBER_OFFSET 2 /* 2 bytes */
69 #define MTP2_HDR_LEN 4 /* length of the header */
70
71 #define MTP2_ANNEX_A_NOT_USED 0
72 #define MTP2_ANNEX_A_USED 1
73 #define MTP2_ANNEX_A_USED_UNKNOWN 2
74
75 /* SunATM pseudo header */
76 struct sunatm_hdr {
77 unsigned char flags; /* destination and traffic type */
78 unsigned char vpi; /* VPI */
79 unsigned short vci; /* VCI */
80 };
81
82 /*
83 * Private data for capturing on DAG devices.
84 */
85 struct pcap_dag {
86 struct pcap_stat stat;
87 #ifdef HAVE_DAG_STREAMS_API
88 u_char *dag_mem_bottom; /* DAG card current memory bottom pointer */
89 u_char *dag_mem_top; /* DAG card current memory top pointer */
90 #else /* HAVE_DAG_STREAMS_API */
91 void *dag_mem_base; /* DAG card memory base address */
92 u_int dag_mem_bottom; /* DAG card current memory bottom offset */
93 u_int dag_mem_top; /* DAG card current memory top offset */
94 #endif /* HAVE_DAG_STREAMS_API */
95 int dag_fcs_bits; /* Number of checksum bits from link layer */
96 int dag_offset_flags; /* Flags to pass to dag_offset(). */
97 int dag_stream; /* DAG stream number */
98 int dag_timeout; /* timeout specified to pcap_open_live.
99 * Same as in linux above, introduce
100 * generally? */
101 };
102
103 typedef struct pcap_dag_node {
104 struct pcap_dag_node *next;
105 pcap_t *p;
106 pid_t pid;
107 } pcap_dag_node_t;
108
109 static pcap_dag_node_t *pcap_dags = NULL;
110 static int atexit_handler_installed = 0;
111 static const unsigned short endian_test_word = 0x0100;
112
113 #define IS_BIGENDIAN() (*((unsigned char *)&endian_test_word))
114
115 #define MAX_DAG_PACKET 65536
116
117 static unsigned char TempPkt[MAX_DAG_PACKET];
118
119 static int dag_setfilter(pcap_t *p, struct bpf_program *fp);
120 static int dag_stats(pcap_t *p, struct pcap_stat *ps);
121 static int dag_set_datalink(pcap_t *p, int dlt);
122 static int dag_get_datalink(pcap_t *p);
123 static int dag_setnonblock(pcap_t *p, int nonblock, char *errbuf);
124
125 static void
delete_pcap_dag(pcap_t * p)126 delete_pcap_dag(pcap_t *p)
127 {
128 pcap_dag_node_t *curr = NULL, *prev = NULL;
129
130 for (prev = NULL, curr = pcap_dags; curr != NULL && curr->p != p; prev = curr, curr = curr->next) {
131 /* empty */
132 }
133
134 if (curr != NULL && curr->p == p) {
135 if (prev != NULL) {
136 prev->next = curr->next;
137 } else {
138 pcap_dags = curr->next;
139 }
140 }
141 }
142
143 /*
144 * Performs a graceful shutdown of the DAG card, frees dynamic memory held
145 * in the pcap_t structure, and closes the file descriptor for the DAG card.
146 */
147
148 static void
dag_platform_cleanup(pcap_t * p)149 dag_platform_cleanup(pcap_t *p)
150 {
151 struct pcap_dag *pd;
152
153 if (p != NULL) {
154 pd = p->priv;
155 #ifdef HAVE_DAG_STREAMS_API
156 if(dag_stop_stream(p->fd, pd->dag_stream) < 0)
157 fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
158
159 if(dag_detach_stream(p->fd, pd->dag_stream) < 0)
160 fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
161 #else
162 if(dag_stop(p->fd) < 0)
163 fprintf(stderr,"dag_stop: %s\n", strerror(errno));
164 #endif /* HAVE_DAG_STREAMS_API */
165 if(p->fd != -1) {
166 if(dag_close(p->fd) < 0)
167 fprintf(stderr,"dag_close: %s\n", strerror(errno));
168 p->fd = -1;
169 }
170 delete_pcap_dag(p);
171 pcap_cleanup_live_common(p);
172 }
173 /* Note: don't need to call close(p->fd) here as dag_close(p->fd) does this. */
174 }
175
176 static void
atexit_handler(void)177 atexit_handler(void)
178 {
179 while (pcap_dags != NULL) {
180 if (pcap_dags->pid == getpid()) {
181 dag_platform_cleanup(pcap_dags->p);
182 } else {
183 delete_pcap_dag(pcap_dags->p);
184 }
185 }
186 }
187
188 static int
new_pcap_dag(pcap_t * p)189 new_pcap_dag(pcap_t *p)
190 {
191 pcap_dag_node_t *node = NULL;
192
193 if ((node = malloc(sizeof(pcap_dag_node_t))) == NULL) {
194 return -1;
195 }
196
197 if (!atexit_handler_installed) {
198 atexit(atexit_handler);
199 atexit_handler_installed = 1;
200 }
201
202 node->next = pcap_dags;
203 node->p = p;
204 node->pid = getpid();
205
206 pcap_dags = node;
207
208 return 0;
209 }
210
211 static unsigned int
dag_erf_ext_header_count(uint8_t * erf,size_t len)212 dag_erf_ext_header_count(uint8_t * erf, size_t len)
213 {
214 uint32_t hdr_num = 0;
215 uint8_t hdr_type;
216
217 /* basic sanity checks */
218 if ( erf == NULL )
219 return 0;
220 if ( len < 16 )
221 return 0;
222
223 /* check if we have any extension headers */
224 if ( (erf[8] & 0x80) == 0x00 )
225 return 0;
226
227 /* loop over the extension headers */
228 do {
229
230 /* sanity check we have enough bytes */
231 if ( len < (24 + (hdr_num * 8)) )
232 return hdr_num;
233
234 /* get the header type */
235 hdr_type = erf[(16 + (hdr_num * 8))];
236 hdr_num++;
237
238 } while ( hdr_type & 0x80 );
239
240 return hdr_num;
241 }
242
243 /*
244 * Read at most max_packets from the capture stream and call the callback
245 * for each of them. Returns the number of packets handled, -1 if an
246 * error occured, or -2 if we were told to break out of the loop.
247 */
248 static int
dag_read(pcap_t * p,int cnt,pcap_handler callback,u_char * user)249 dag_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
250 {
251 struct pcap_dag *pd = p->priv;
252 unsigned int processed = 0;
253 int flags = pd->dag_offset_flags;
254 unsigned int nonblocking = flags & DAGF_NONBLOCK;
255 unsigned int num_ext_hdr = 0;
256
257 /* Get the next bufferful of packets (if necessary). */
258 while (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size) {
259
260 /*
261 * Has "pcap_breakloop()" been called?
262 */
263 if (p->break_loop) {
264 /*
265 * Yes - clear the flag that indicates that
266 * it has, and return -2 to indicate that
267 * we were told to break out of the loop.
268 */
269 p->break_loop = 0;
270 return -2;
271 }
272
273 #ifdef HAVE_DAG_STREAMS_API
274 /* dag_advance_stream() will block (unless nonblock is called)
275 * until 64kB of data has accumulated.
276 * If to_ms is set, it will timeout before 64kB has accumulated.
277 * We wait for 64kB because processing a few packets at a time
278 * can cause problems at high packet rates (>200kpps) due
279 * to inefficiencies.
280 * This does mean if to_ms is not specified the capture may 'hang'
281 * for long periods if the data rate is extremely slow (<64kB/sec)
282 * If non-block is specified it will return immediately. The user
283 * is then responsible for efficiency.
284 */
285 if ( NULL == (pd->dag_mem_top = dag_advance_stream(p->fd, pd->dag_stream, &(pd->dag_mem_bottom))) ) {
286 return -1;
287 }
288 #else
289 /* dag_offset does not support timeouts */
290 pd->dag_mem_top = dag_offset(p->fd, &(pd->dag_mem_bottom), flags);
291 #endif /* HAVE_DAG_STREAMS_API */
292
293 if (nonblocking && (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size))
294 {
295 /* Pcap is configured to process only available packets, and there aren't any, return immediately. */
296 return 0;
297 }
298
299 if(!nonblocking &&
300 pd->dag_timeout &&
301 (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size))
302 {
303 /* Blocking mode, but timeout set and no data has arrived, return anyway.*/
304 return 0;
305 }
306
307 }
308
309 /* Process the packets. */
310 while (pd->dag_mem_top - pd->dag_mem_bottom >= dag_record_size) {
311
312 unsigned short packet_len = 0;
313 int caplen = 0;
314 struct pcap_pkthdr pcap_header;
315
316 #ifdef HAVE_DAG_STREAMS_API
317 dag_record_t *header = (dag_record_t *)(pd->dag_mem_bottom);
318 #else
319 dag_record_t *header = (dag_record_t *)(pd->dag_mem_base + pd->dag_mem_bottom);
320 #endif /* HAVE_DAG_STREAMS_API */
321
322 u_char *dp = ((u_char *)header); /* + dag_record_size; */
323 unsigned short rlen;
324
325 /*
326 * Has "pcap_breakloop()" been called?
327 */
328 if (p->break_loop) {
329 /*
330 * Yes - clear the flag that indicates that
331 * it has, and return -2 to indicate that
332 * we were told to break out of the loop.
333 */
334 p->break_loop = 0;
335 return -2;
336 }
337
338 rlen = ntohs(header->rlen);
339 if (rlen < dag_record_size)
340 {
341 strncpy(p->errbuf, "dag_read: record too small", PCAP_ERRBUF_SIZE);
342 return -1;
343 }
344 pd->dag_mem_bottom += rlen;
345
346 /* Count lost packets. */
347 switch((header->type & 0x7f)) {
348 /* in these types the color value overwrites the lctr */
349 case TYPE_COLOR_HDLC_POS:
350 case TYPE_COLOR_ETH:
351 case TYPE_DSM_COLOR_HDLC_POS:
352 case TYPE_DSM_COLOR_ETH:
353 case TYPE_COLOR_MC_HDLC_POS:
354 case TYPE_COLOR_HASH_ETH:
355 case TYPE_COLOR_HASH_POS:
356 break;
357
358 default:
359 if (header->lctr) {
360 if (pd->stat.ps_drop > (UINT_MAX - ntohs(header->lctr))) {
361 pd->stat.ps_drop = UINT_MAX;
362 } else {
363 pd->stat.ps_drop += ntohs(header->lctr);
364 }
365 }
366 }
367
368 if ((header->type & 0x7f) == TYPE_PAD) {
369 continue;
370 }
371
372 num_ext_hdr = dag_erf_ext_header_count(dp, rlen);
373
374 /* ERF encapsulation */
375 /* The Extensible Record Format is not dropped for this kind of encapsulation,
376 * and will be handled as a pseudo header by the decoding application.
377 * The information carried in the ERF header and in the optional subheader (if present)
378 * could be merged with the libpcap information, to offer a better decoding.
379 * The packet length is
380 * o the length of the packet on the link (header->wlen),
381 * o plus the length of the ERF header (dag_record_size), as the length of the
382 * pseudo header will be adjusted during the decoding,
383 * o plus the length of the optional subheader (if present).
384 *
385 * The capture length is header.rlen and the byte stuffing for alignment will be dropped
386 * if the capture length is greater than the packet length.
387 */
388 if (p->linktype == DLT_ERF) {
389 packet_len = ntohs(header->wlen) + dag_record_size;
390 caplen = rlen;
391 switch ((header->type & 0x7f)) {
392 case TYPE_MC_AAL5:
393 case TYPE_MC_ATM:
394 case TYPE_MC_HDLC:
395 case TYPE_MC_RAW_CHANNEL:
396 case TYPE_MC_RAW:
397 case TYPE_MC_AAL2:
398 case TYPE_COLOR_MC_HDLC_POS:
399 packet_len += 4; /* MC header */
400 break;
401
402 case TYPE_COLOR_HASH_ETH:
403 case TYPE_DSM_COLOR_ETH:
404 case TYPE_COLOR_ETH:
405 case TYPE_ETH:
406 packet_len += 2; /* ETH header */
407 break;
408 } /* switch type */
409
410 /* Include ERF extension headers */
411 packet_len += (8 * num_ext_hdr);
412
413 if (caplen > packet_len) {
414 caplen = packet_len;
415 }
416 } else {
417 /* Other kind of encapsulation according to the header Type */
418
419 /* Skip over generic ERF header */
420 dp += dag_record_size;
421 /* Skip over extension headers */
422 dp += 8 * num_ext_hdr;
423
424 switch((header->type & 0x7f)) {
425 case TYPE_ATM:
426 case TYPE_AAL5:
427 if (header->type == TYPE_AAL5) {
428 packet_len = ntohs(header->wlen);
429 caplen = rlen - dag_record_size;
430 }
431 case TYPE_MC_ATM:
432 if (header->type == TYPE_MC_ATM) {
433 caplen = packet_len = ATM_CELL_SIZE;
434 dp+=4;
435 }
436 case TYPE_MC_AAL5:
437 if (header->type == TYPE_MC_AAL5) {
438 packet_len = ntohs(header->wlen);
439 caplen = rlen - dag_record_size - 4;
440 dp+=4;
441 }
442 if (header->type == TYPE_ATM) {
443 caplen = packet_len = ATM_CELL_SIZE;
444 }
445 if (p->linktype == DLT_SUNATM) {
446 struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
447 unsigned long rawatm;
448
449 rawatm = ntohl(*((unsigned long *)dp));
450 sunatm->vci = htons((rawatm >> 4) & 0xffff);
451 sunatm->vpi = (rawatm >> 20) & 0x00ff;
452 sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) |
453 ((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
454 ((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 :
455 ((dp[ATM_HDR_SIZE] == 0xaa &&
456 dp[ATM_HDR_SIZE+1] == 0xaa &&
457 dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
458
459 } else {
460 packet_len -= ATM_HDR_SIZE;
461 caplen -= ATM_HDR_SIZE;
462 dp += ATM_HDR_SIZE;
463 }
464 break;
465
466 case TYPE_COLOR_HASH_ETH:
467 case TYPE_DSM_COLOR_ETH:
468 case TYPE_COLOR_ETH:
469 case TYPE_ETH:
470 packet_len = ntohs(header->wlen);
471 packet_len -= (pd->dag_fcs_bits >> 3);
472 caplen = rlen - dag_record_size - 2;
473 if (caplen > packet_len) {
474 caplen = packet_len;
475 }
476 dp += 2;
477 break;
478
479 case TYPE_COLOR_HASH_POS:
480 case TYPE_DSM_COLOR_HDLC_POS:
481 case TYPE_COLOR_HDLC_POS:
482 case TYPE_HDLC_POS:
483 packet_len = ntohs(header->wlen);
484 packet_len -= (pd->dag_fcs_bits >> 3);
485 caplen = rlen - dag_record_size;
486 if (caplen > packet_len) {
487 caplen = packet_len;
488 }
489 break;
490
491 case TYPE_COLOR_MC_HDLC_POS:
492 case TYPE_MC_HDLC:
493 packet_len = ntohs(header->wlen);
494 packet_len -= (pd->dag_fcs_bits >> 3);
495 caplen = rlen - dag_record_size - 4;
496 if (caplen > packet_len) {
497 caplen = packet_len;
498 }
499 /* jump the MC_HDLC_HEADER */
500 dp += 4;
501 #ifdef DLT_MTP2_WITH_PHDR
502 if (p->linktype == DLT_MTP2_WITH_PHDR) {
503 /* Add the MTP2 Pseudo Header */
504 caplen += MTP2_HDR_LEN;
505 packet_len += MTP2_HDR_LEN;
506
507 TempPkt[MTP2_SENT_OFFSET] = 0;
508 TempPkt[MTP2_ANNEX_A_USED_OFFSET] = MTP2_ANNEX_A_USED_UNKNOWN;
509 *(TempPkt+MTP2_LINK_NUMBER_OFFSET) = ((header->rec.mc_hdlc.mc_header>>16)&0x01);
510 *(TempPkt+MTP2_LINK_NUMBER_OFFSET+1) = ((header->rec.mc_hdlc.mc_header>>24)&0xff);
511 memcpy(TempPkt+MTP2_HDR_LEN, dp, caplen);
512 dp = TempPkt;
513 }
514 #endif
515 break;
516
517 case TYPE_IPV4:
518 case TYPE_IPV6:
519 packet_len = ntohs(header->wlen);
520 caplen = rlen - dag_record_size;
521 if (caplen > packet_len) {
522 caplen = packet_len;
523 }
524 break;
525
526 /* These types have no matching 'native' DLT, but can be used with DLT_ERF above */
527 case TYPE_MC_RAW:
528 case TYPE_MC_RAW_CHANNEL:
529 case TYPE_IP_COUNTER:
530 case TYPE_TCP_FLOW_COUNTER:
531 case TYPE_INFINIBAND:
532 case TYPE_RAW_LINK:
533 case TYPE_INFINIBAND_LINK:
534 default:
535 /* Unhandled ERF type.
536 * Ignore rather than generating error
537 */
538 continue;
539 } /* switch type */
540
541 /* Skip over extension headers */
542 caplen -= (8 * num_ext_hdr);
543
544 } /* ERF encapsulation */
545
546 if (caplen > p->snapshot)
547 caplen = p->snapshot;
548
549 /* Run the packet filter if there is one. */
550 if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
551
552 /* convert between timestamp formats */
553 register unsigned long long ts;
554
555 if (IS_BIGENDIAN()) {
556 ts = SWAPLL(header->ts);
557 } else {
558 ts = header->ts;
559 }
560
561 pcap_header.ts.tv_sec = ts >> 32;
562 ts = (ts & 0xffffffffULL) * 1000000;
563 ts += 0x80000000; /* rounding */
564 pcap_header.ts.tv_usec = ts >> 32;
565 if (pcap_header.ts.tv_usec >= 1000000) {
566 pcap_header.ts.tv_usec -= 1000000;
567 pcap_header.ts.tv_sec++;
568 }
569
570 /* Fill in our own header data */
571 pcap_header.caplen = caplen;
572 pcap_header.len = packet_len;
573
574 /* Count the packet. */
575 pd->stat.ps_recv++;
576
577 /* Call the user supplied callback function */
578 callback(user, &pcap_header, dp);
579
580 /* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
581 processed++;
582 if (processed == cnt && !PACKET_COUNT_IS_UNLIMITED(cnt))
583 {
584 /* Reached the user-specified limit. */
585 return cnt;
586 }
587 }
588 }
589
590 return processed;
591 }
592
593 static int
dag_inject(pcap_t * p,const void * buf _U_,size_t size _U_)594 dag_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
595 {
596 strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
597 PCAP_ERRBUF_SIZE);
598 return (-1);
599 }
600
601 /*
602 * Get a handle for a live capture from the given DAG device. Passing a NULL
603 * device will result in a failure. The promisc flag is ignored because DAG
604 * cards are always promiscuous. The to_ms parameter is used in setting the
605 * API polling parameters.
606 *
607 * snaplen is now also ignored, until we get per-stream slen support. Set
608 * slen with approprite DAG tool BEFORE pcap_activate().
609 *
610 * See also pcap(3).
611 */
dag_activate(pcap_t * handle)612 static int dag_activate(pcap_t* handle)
613 {
614 struct pcap_dag *handlep = handle->priv;
615 #if 0
616 char conf[30]; /* dag configure string */
617 #endif
618 char *s;
619 int n;
620 daginf_t* daginf;
621 char * newDev = NULL;
622 char * device = handle->opt.source;
623 #ifdef HAVE_DAG_STREAMS_API
624 uint32_t mindata;
625 struct timeval maxwait;
626 struct timeval poll;
627 #endif
628
629 if (device == NULL) {
630 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "device is NULL: %s", pcap_strerror(errno));
631 return -1;
632 }
633
634 /* Initialize some components of the pcap structure. */
635
636 #ifdef HAVE_DAG_STREAMS_API
637 newDev = (char *)malloc(strlen(device) + 16);
638 if (newDev == NULL) {
639 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
640 goto fail;
641 }
642
643 /* Parse input name to get dag device and stream number if provided */
644 if (dag_parse_name(device, newDev, strlen(device) + 16, &handlep->dag_stream) < 0) {
645 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: %s\n", pcap_strerror(errno));
646 goto fail;
647 }
648 device = newDev;
649
650 if (handlep->dag_stream%2) {
651 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: tx (even numbered) streams not supported for capture\n");
652 goto fail;
653 }
654 #else
655 if (strncmp(device, "/dev/", 5) != 0) {
656 newDev = (char *)malloc(strlen(device) + 5);
657 if (newDev == NULL) {
658 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
659 goto fail;
660 }
661 strcpy(newDev, "/dev/");
662 strcat(newDev, device);
663 device = newDev;
664 }
665 #endif /* HAVE_DAG_STREAMS_API */
666
667 /* setup device parameters */
668 if((handle->fd = dag_open((char *)device)) < 0) {
669 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_open %s: %s", device, pcap_strerror(errno));
670 goto fail;
671 }
672
673 #ifdef HAVE_DAG_STREAMS_API
674 /* Open requested stream. Can fail if already locked or on error */
675 if (dag_attach_stream(handle->fd, handlep->dag_stream, 0, 0) < 0) {
676 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_attach_stream: %s\n", pcap_strerror(errno));
677 goto failclose;
678 }
679
680 /* Set up default poll parameters for stream
681 * Can be overridden by pcap_set_nonblock()
682 */
683 if (dag_get_stream_poll(handle->fd, handlep->dag_stream,
684 &mindata, &maxwait, &poll) < 0) {
685 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
686 goto faildetach;
687 }
688
689 if (handle->opt.immediate) {
690 /* Call callback immediately.
691 * XXX - is this the right way to handle this?
692 */
693 mindata = 0;
694 } else {
695 /* Amount of data to collect in Bytes before calling callbacks.
696 * Important for efficiency, but can introduce latency
697 * at low packet rates if to_ms not set!
698 */
699 mindata = 65536;
700 }
701
702 /* Obey opt.timeout (was to_ms) if supplied. This is a good idea!
703 * Recommend 10-100ms. Calls will time out even if no data arrived.
704 */
705 maxwait.tv_sec = handle->opt.timeout/1000;
706 maxwait.tv_usec = (handle->opt.timeout%1000) * 1000;
707
708 if (dag_set_stream_poll(handle->fd, handlep->dag_stream,
709 mindata, &maxwait, &poll) < 0) {
710 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
711 goto faildetach;
712 }
713
714 #else
715 if((handlep->dag_mem_base = dag_mmap(handle->fd)) == MAP_FAILED) {
716 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_mmap %s: %s\n", device, pcap_strerror(errno));
717 goto failclose;
718 }
719
720 #endif /* HAVE_DAG_STREAMS_API */
721
722 /* XXX Not calling dag_configure() to set slen; this is unsafe in
723 * multi-stream environments as the gpp config is global.
724 * Once the firmware provides 'per-stream slen' this can be supported
725 * again via the Config API without side-effects */
726 #if 0
727 /* set the card snap length to the specified snaplen parameter */
728 /* This is a really bad idea, as different cards have different
729 * valid slen ranges. Should fix in Config API. */
730 if (handle->snapshot == 0 || handle->snapshot > MAX_DAG_SNAPLEN) {
731 handle->snapshot = MAX_DAG_SNAPLEN;
732 } else if (snaplen < MIN_DAG_SNAPLEN) {
733 handle->snapshot = MIN_DAG_SNAPLEN;
734 }
735 /* snap len has to be a multiple of 4 */
736 snprintf(conf, 30, "varlen slen=%d", (snaplen + 3) & ~3);
737
738 if(dag_configure(handle->fd, conf) < 0) {
739 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_configure %s: %s\n", device, pcap_strerror(errno));
740 goto faildetach;
741 }
742 #endif
743
744 #ifdef HAVE_DAG_STREAMS_API
745 if(dag_start_stream(handle->fd, handlep->dag_stream) < 0) {
746 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start_stream %s: %s\n", device, pcap_strerror(errno));
747 goto faildetach;
748 }
749 #else
750 if(dag_start(handle->fd) < 0) {
751 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start %s: %s\n", device, pcap_strerror(errno));
752 goto failclose;
753 }
754 #endif /* HAVE_DAG_STREAMS_API */
755
756 /*
757 * Important! You have to ensure bottom is properly
758 * initialized to zero on startup, it won't give you
759 * a compiler warning if you make this mistake!
760 */
761 handlep->dag_mem_bottom = 0;
762 handlep->dag_mem_top = 0;
763
764 /*
765 * Find out how many FCS bits we should strip.
766 * First, query the card to see if it strips the FCS.
767 */
768 daginf = dag_info(handle->fd);
769 if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code)) {
770 /* DAG 4.2S and 4.23S already strip the FCS. Stripping the final word again truncates the packet. */
771 handlep->dag_fcs_bits = 0;
772
773 /* Note that no FCS will be supplied. */
774 handle->linktype_ext = LT_FCS_DATALINK_EXT(0);
775 } else {
776 /*
777 * Start out assuming it's 32 bits.
778 */
779 handlep->dag_fcs_bits = 32;
780
781 /* Allow an environment variable to override. */
782 if ((s = getenv("ERF_FCS_BITS")) != NULL) {
783 if ((n = atoi(s)) == 0 || n == 16 || n == 32) {
784 handlep->dag_fcs_bits = n;
785 } else {
786 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
787 "pcap_activate %s: bad ERF_FCS_BITS value (%d) in environment\n", device, n);
788 goto failstop;
789 }
790 }
791
792 /*
793 * Did the user request that they not be stripped?
794 */
795 if ((s = getenv("ERF_DONT_STRIP_FCS")) != NULL) {
796 /* Yes. Note the number of bytes that will be
797 supplied. */
798 handle->linktype_ext = LT_FCS_DATALINK_EXT(handlep->dag_fcs_bits/16);
799
800 /* And don't strip them. */
801 handlep->dag_fcs_bits = 0;
802 }
803 }
804
805 handlep->dag_timeout = handle->opt.timeout;
806
807 handle->linktype = -1;
808 if (dag_get_datalink(handle) < 0)
809 goto failstop;
810
811 handle->bufsize = 0;
812
813 if (new_pcap_dag(handle) < 0) {
814 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "new_pcap_dag %s: %s\n", device, pcap_strerror(errno));
815 goto failstop;
816 }
817
818 /*
819 * "select()" and "poll()" don't work on DAG device descriptors.
820 */
821 handle->selectable_fd = -1;
822
823 if (newDev != NULL) {
824 free((char *)newDev);
825 }
826
827 handle->read_op = dag_read;
828 handle->inject_op = dag_inject;
829 handle->setfilter_op = dag_setfilter;
830 handle->setdirection_op = NULL; /* Not implemented.*/
831 handle->set_datalink_op = dag_set_datalink;
832 handle->getnonblock_op = pcap_getnonblock_fd;
833 handle->setnonblock_op = dag_setnonblock;
834 handle->stats_op = dag_stats;
835 handle->cleanup_op = dag_platform_cleanup;
836 handlep->stat.ps_drop = 0;
837 handlep->stat.ps_recv = 0;
838 handlep->stat.ps_ifdrop = 0;
839 return 0;
840
841 #ifdef HAVE_DAG_STREAMS_API
842 failstop:
843 if (dag_stop_stream(handle->fd, handlep->dag_stream) < 0) {
844 fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
845 }
846
847 faildetach:
848 if (dag_detach_stream(handle->fd, handlep->dag_stream) < 0)
849 fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
850 #else
851 failstop:
852 if (dag_stop(handle->fd) < 0)
853 fprintf(stderr,"dag_stop: %s\n", strerror(errno));
854 #endif /* HAVE_DAG_STREAMS_API */
855
856 failclose:
857 if (dag_close(handle->fd) < 0)
858 fprintf(stderr,"dag_close: %s\n", strerror(errno));
859 delete_pcap_dag(handle);
860
861 fail:
862 pcap_cleanup_live_common(handle);
863 if (newDev != NULL) {
864 free((char *)newDev);
865 }
866
867 return PCAP_ERROR;
868 }
869
dag_create(const char * device,char * ebuf,int * is_ours)870 pcap_t *dag_create(const char *device, char *ebuf, int *is_ours)
871 {
872 const char *cp;
873 char *cpend;
874 long devnum;
875 pcap_t *p;
876 #ifdef HAVE_DAG_STREAMS_API
877 long stream = 0;
878 #endif
879
880 /* Does this look like a DAG device? */
881 cp = strrchr(device, '/');
882 if (cp == NULL)
883 cp = device;
884 /* Does it begin with "dag"? */
885 if (strncmp(cp, "dag", 3) != 0) {
886 /* Nope, doesn't begin with "dag" */
887 *is_ours = 0;
888 return NULL;
889 }
890 /* Yes - is "dag" followed by a number from 0 to DAG_MAX_BOARDS-1 */
891 cp += 3;
892 devnum = strtol(cp, &cpend, 10);
893 #ifdef HAVE_DAG_STREAMS_API
894 if (*cpend == ':') {
895 /* Followed by a stream number. */
896 stream = strtol(++cpend, &cpend, 10);
897 }
898 #endif
899 if (cpend == cp || *cpend != '\0') {
900 /* Not followed by a number. */
901 *is_ours = 0;
902 return NULL;
903 }
904 if (devnum < 0 || devnum >= DAG_MAX_BOARDS) {
905 /* Followed by a non-valid number. */
906 *is_ours = 0;
907 return NULL;
908 }
909 #ifdef HAVE_DAG_STREAMS_API
910 if (stream <0 || stream >= DAG_STREAM_MAX) {
911 /* Followed by a non-valid stream number. */
912 *is_ours = 0;
913 return NULL;
914 }
915 #endif
916
917 /* OK, it's probably ours. */
918 *is_ours = 1;
919
920 p = pcap_create_common(device, ebuf, sizeof (struct pcap_dag));
921 if (p == NULL)
922 return NULL;
923
924 p->activate_op = dag_activate;
925 return p;
926 }
927
928 static int
dag_stats(pcap_t * p,struct pcap_stat * ps)929 dag_stats(pcap_t *p, struct pcap_stat *ps) {
930 struct pcap_dag *pd = p->priv;
931
932 /* This needs to be filled out correctly. Hopefully a dagapi call will
933 provide all necessary information.
934 */
935 /*pd->stat.ps_recv = 0;*/
936 /*pd->stat.ps_drop = 0;*/
937
938 *ps = pd->stat;
939
940 return 0;
941 }
942
943 /*
944 * Previously we just generated a list of all possible names and let
945 * pcap_add_if() attempt to open each one, but with streams this adds up
946 * to 81 possibilities which is inefficient.
947 *
948 * Since we know more about the devices we can prune the tree here.
949 * pcap_add_if() will still retest each device but the total number of
950 * open attempts will still be much less than the naive approach.
951 */
952 int
dag_findalldevs(pcap_if_t ** devlistp,char * errbuf)953 dag_findalldevs(pcap_if_t **devlistp, char *errbuf)
954 {
955 char name[12]; /* XXX - pick a size */
956 int ret = 0;
957 int c;
958 char dagname[DAGNAME_BUFSIZE];
959 int dagstream;
960 int dagfd;
961
962 /* Try all the DAGs 0-DAG_MAX_BOARDS */
963 for (c = 0; c < DAG_MAX_BOARDS; c++) {
964 snprintf(name, 12, "dag%d", c);
965 if (-1 == dag_parse_name(name, dagname, DAGNAME_BUFSIZE, &dagstream))
966 {
967 return -1;
968 }
969 if ( (dagfd = dag_open(dagname)) >= 0 ) {
970 if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
971 /*
972 * Failure.
973 */
974 ret = -1;
975 }
976 #ifdef HAVE_DAG_STREAMS_API
977 {
978 int stream, rxstreams;
979 rxstreams = dag_rx_get_stream_count(dagfd);
980 for(stream=0;stream<DAG_STREAM_MAX;stream+=2) {
981 if (0 == dag_attach_stream(dagfd, stream, 0, 0)) {
982 dag_detach_stream(dagfd, stream);
983
984 snprintf(name, 10, "dag%d:%d", c, stream);
985 if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
986 /*
987 * Failure.
988 */
989 ret = -1;
990 }
991
992 rxstreams--;
993 if(rxstreams <= 0) {
994 break;
995 }
996 }
997 }
998 }
999 #endif /* HAVE_DAG_STREAMS_API */
1000 dag_close(dagfd);
1001 }
1002
1003 }
1004 return (ret);
1005 }
1006
1007 /*
1008 * Installs the given bpf filter program in the given pcap structure. There is
1009 * no attempt to store the filter in kernel memory as that is not supported
1010 * with DAG cards.
1011 */
1012 static int
dag_setfilter(pcap_t * p,struct bpf_program * fp)1013 dag_setfilter(pcap_t *p, struct bpf_program *fp)
1014 {
1015 if (!p)
1016 return -1;
1017 if (!fp) {
1018 strncpy(p->errbuf, "setfilter: No filter specified",
1019 sizeof(p->errbuf));
1020 return -1;
1021 }
1022
1023 /* Make our private copy of the filter */
1024
1025 if (install_bpf_program(p, fp) < 0)
1026 return -1;
1027
1028 return (0);
1029 }
1030
1031 static int
dag_set_datalink(pcap_t * p,int dlt)1032 dag_set_datalink(pcap_t *p, int dlt)
1033 {
1034 p->linktype = dlt;
1035
1036 return (0);
1037 }
1038
1039 static int
dag_setnonblock(pcap_t * p,int nonblock,char * errbuf)1040 dag_setnonblock(pcap_t *p, int nonblock, char *errbuf)
1041 {
1042 struct pcap_dag *pd = p->priv;
1043
1044 /*
1045 * Set non-blocking mode on the FD.
1046 * XXX - is that necessary? If not, don't bother calling it,
1047 * and have a "dag_getnonblock()" function that looks at
1048 * "pd->dag_offset_flags".
1049 */
1050 if (pcap_setnonblock_fd(p, nonblock, errbuf) < 0)
1051 return (-1);
1052 #ifdef HAVE_DAG_STREAMS_API
1053 {
1054 uint32_t mindata;
1055 struct timeval maxwait;
1056 struct timeval poll;
1057
1058 if (dag_get_stream_poll(p->fd, pd->dag_stream,
1059 &mindata, &maxwait, &poll) < 0) {
1060 snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
1061 return -1;
1062 }
1063
1064 /* Amount of data to collect in Bytes before calling callbacks.
1065 * Important for efficiency, but can introduce latency
1066 * at low packet rates if to_ms not set!
1067 */
1068 if(nonblock)
1069 mindata = 0;
1070 else
1071 mindata = 65536;
1072
1073 if (dag_set_stream_poll(p->fd, pd->dag_stream,
1074 mindata, &maxwait, &poll) < 0) {
1075 snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
1076 return -1;
1077 }
1078 }
1079 #endif /* HAVE_DAG_STREAMS_API */
1080 if (nonblock) {
1081 pd->dag_offset_flags |= DAGF_NONBLOCK;
1082 } else {
1083 pd->dag_offset_flags &= ~DAGF_NONBLOCK;
1084 }
1085 return (0);
1086 }
1087
1088 static int
dag_get_datalink(pcap_t * p)1089 dag_get_datalink(pcap_t *p)
1090 {
1091 struct pcap_dag *pd = p->priv;
1092 int index=0, dlt_index=0;
1093 uint8_t types[255];
1094
1095 memset(types, 0, 255);
1096
1097 if (p->dlt_list == NULL && (p->dlt_list = malloc(255*sizeof(*(p->dlt_list)))) == NULL) {
1098 (void)snprintf(p->errbuf, sizeof(p->errbuf), "malloc: %s", pcap_strerror(errno));
1099 return (-1);
1100 }
1101
1102 p->linktype = 0;
1103
1104 #ifdef HAVE_DAG_GET_STREAM_ERF_TYPES
1105 /* Get list of possible ERF types for this card */
1106 if (dag_get_stream_erf_types(p->fd, pd->dag_stream, types, 255) < 0) {
1107 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_stream_erf_types: %s", pcap_strerror(errno));
1108 return (-1);
1109 }
1110
1111 while (types[index]) {
1112
1113 #elif defined HAVE_DAG_GET_ERF_TYPES
1114 /* Get list of possible ERF types for this card */
1115 if (dag_get_erf_types(p->fd, types, 255) < 0) {
1116 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_erf_types: %s", pcap_strerror(errno));
1117 return (-1);
1118 }
1119
1120 while (types[index]) {
1121 #else
1122 /* Check the type through a dagapi call. */
1123 types[index] = dag_linktype(p->fd);
1124
1125 {
1126 #endif
1127 switch((types[index] & 0x7f)) {
1128
1129 case TYPE_HDLC_POS:
1130 case TYPE_COLOR_HDLC_POS:
1131 case TYPE_DSM_COLOR_HDLC_POS:
1132 case TYPE_COLOR_HASH_POS:
1133
1134 if (p->dlt_list != NULL) {
1135 p->dlt_list[dlt_index++] = DLT_CHDLC;
1136 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1137 p->dlt_list[dlt_index++] = DLT_FRELAY;
1138 }
1139 if(!p->linktype)
1140 p->linktype = DLT_CHDLC;
1141 break;
1142
1143 case TYPE_ETH:
1144 case TYPE_COLOR_ETH:
1145 case TYPE_DSM_COLOR_ETH:
1146 case TYPE_COLOR_HASH_ETH:
1147 /*
1148 * This is (presumably) a real Ethernet capture; give it a
1149 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
1150 * that an application can let you choose it, in case you're
1151 * capturing DOCSIS traffic that a Cisco Cable Modem
1152 * Termination System is putting out onto an Ethernet (it
1153 * doesn't put an Ethernet header onto the wire, it puts raw
1154 * DOCSIS frames out on the wire inside the low-level
1155 * Ethernet framing).
1156 */
1157 if (p->dlt_list != NULL) {
1158 p->dlt_list[dlt_index++] = DLT_EN10MB;
1159 p->dlt_list[dlt_index++] = DLT_DOCSIS;
1160 }
1161 if(!p->linktype)
1162 p->linktype = DLT_EN10MB;
1163 break;
1164
1165 case TYPE_ATM:
1166 case TYPE_AAL5:
1167 case TYPE_MC_ATM:
1168 case TYPE_MC_AAL5:
1169 if (p->dlt_list != NULL) {
1170 p->dlt_list[dlt_index++] = DLT_ATM_RFC1483;
1171 p->dlt_list[dlt_index++] = DLT_SUNATM;
1172 }
1173 if(!p->linktype)
1174 p->linktype = DLT_ATM_RFC1483;
1175 break;
1176
1177 case TYPE_COLOR_MC_HDLC_POS:
1178 case TYPE_MC_HDLC:
1179 if (p->dlt_list != NULL) {
1180 p->dlt_list[dlt_index++] = DLT_CHDLC;
1181 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1182 p->dlt_list[dlt_index++] = DLT_FRELAY;
1183 p->dlt_list[dlt_index++] = DLT_MTP2;
1184 p->dlt_list[dlt_index++] = DLT_MTP2_WITH_PHDR;
1185 p->dlt_list[dlt_index++] = DLT_LAPD;
1186 }
1187 if(!p->linktype)
1188 p->linktype = DLT_CHDLC;
1189 break;
1190
1191 case TYPE_IPV4:
1192 case TYPE_IPV6:
1193 if(!p->linktype)
1194 p->linktype = DLT_RAW;
1195 break;
1196
1197 case TYPE_LEGACY:
1198 case TYPE_MC_RAW:
1199 case TYPE_MC_RAW_CHANNEL:
1200 case TYPE_IP_COUNTER:
1201 case TYPE_TCP_FLOW_COUNTER:
1202 case TYPE_INFINIBAND:
1203 case TYPE_RAW_LINK:
1204 case TYPE_INFINIBAND_LINK:
1205 default:
1206 /* Libpcap cannot deal with these types yet */
1207 /* Add no 'native' DLTs, but still covered by DLT_ERF */
1208 break;
1209
1210 } /* switch */
1211 index++;
1212 }
1213
1214 p->dlt_list[dlt_index++] = DLT_ERF;
1215
1216 p->dlt_count = dlt_index;
1217
1218 if(!p->linktype)
1219 p->linktype = DLT_ERF;
1220
1221 return p->linktype;
1222 }
1223