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