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1 /*
2  * Copyright (c) 1999 - 2005 NetGroup, Politecnico di Torino (Italy)
3  * Copyright (c) 2005 - 2007 CACE Technologies, Davis (California)
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  * notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  * notice, this list of conditions and the following disclaimer in the
14  * documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the Politecnico di Torino, CACE Technologies
16  * nor the names of its contributors may be used to endorse or promote
17  * products derived from this software without specific prior written
18  * permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  *
32  */
33 
34 #ifndef lint
35 static const char rcsid[] _U_ =
36     "@(#) $Header: /tcpdump/master/libpcap/pcap-win32.c,v 1.25.2.7 2007/06/14 22:07:14 gianluca Exp $ (LBL)";
37 #endif
38 
39 #include <pcap-int.h>
40 #include <Packet32.h>
41 #include <Ntddndis.h>
42 #ifdef HAVE_DAG_API
43 #include <dagnew.h>
44 #include <dagapi.h>
45 #endif /* HAVE_DAG_API */
46 #ifdef __MINGW32__
47 int* _errno();
48 #define errno (*_errno())
49 #endif /* __MINGW32__ */
50 
51 static int pcap_setfilter_win32_npf(pcap_t *, struct bpf_program *);
52 static int pcap_setfilter_win32_dag(pcap_t *, struct bpf_program *);
53 static int pcap_getnonblock_win32(pcap_t *, char *);
54 static int pcap_setnonblock_win32(pcap_t *, int, char *);
55 
56 #define	PcapBufSize 256000	/*dimension of the buffer in the pcap_t structure*/
57 #define	SIZE_BUF 1000000
58 
59 /* Equivalent to ntohs(), but a lot faster under Windows */
60 #define SWAPS(_X) ((_X & 0xff) << 8) | (_X >> 8)
61 
62 /*
63  * Header that the WinPcap driver associates to the packets.
64  * Once was in bpf.h
65  */
66 struct bpf_hdr {
67 	struct timeval	bh_tstamp;	/* time stamp */
68 	bpf_u_int32	bh_caplen;	/* length of captured portion */
69 	bpf_u_int32	bh_datalen;	/* original length of packet */
70 	u_short		bh_hdrlen;	/* length of bpf header (this struct
71 					   plus alignment padding) */
72 };
73 
74 /* Start winsock */
75 int
wsockinit()76 wsockinit()
77 {
78 	WORD wVersionRequested;
79 	WSADATA wsaData;
80 	int err;
81 	wVersionRequested = MAKEWORD( 1, 1);
82 	err = WSAStartup( wVersionRequested, &wsaData );
83 	if ( err != 0 )
84 	{
85 		return -1;
86 	}
87 	return 0;
88 }
89 
90 
91 static int
pcap_stats_win32(pcap_t * p,struct pcap_stat * ps)92 pcap_stats_win32(pcap_t *p, struct pcap_stat *ps)
93 {
94 
95 	if(PacketGetStats(p->adapter, (struct bpf_stat*)ps) != TRUE){
96 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "PacketGetStats error: %s", pcap_win32strerror());
97 		return -1;
98 	}
99 
100 	return 0;
101 }
102 
103 static int
pcap_read_win32_npf(pcap_t * p,int cnt,pcap_handler callback,u_char * user)104 pcap_read_win32_npf(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
105 {
106 	int cc;
107 	int n = 0;
108 	register u_char *bp, *ep;
109 
110 	cc = p->cc;
111 	if (p->cc == 0) {
112 		/*
113 		 * Has "pcap_breakloop()" been called?
114 		 */
115 		if (p->break_loop) {
116 			/*
117 			 * Yes - clear the flag that indicates that it
118 			 * has, and return -2 to indicate that we were
119 			 * told to break out of the loop.
120 			 */
121 			p->break_loop = 0;
122 			return (-2);
123 		}
124 
125 	    /* capture the packets */
126 		if(PacketReceivePacket(p->adapter,p->Packet,TRUE)==FALSE){
127 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "read error: PacketReceivePacket failed");
128 			return (-1);
129 		}
130 
131 		cc = p->Packet->ulBytesReceived;
132 
133 		bp = p->Packet->Buffer;
134 	}
135 	else
136 		bp = p->bp;
137 
138 	/*
139 	 * Loop through each packet.
140 	 */
141 #define bhp ((struct bpf_hdr *)bp)
142 	ep = bp + cc;
143 	while (1) {
144 		register int caplen, hdrlen;
145 
146 		/*
147 		 * Has "pcap_breakloop()" been called?
148 		 * If so, return immediately - if we haven't read any
149 		 * packets, clear the flag and return -2 to indicate
150 		 * that we were told to break out of the loop, otherwise
151 		 * leave the flag set, so that the *next* call will break
152 		 * out of the loop without having read any packets, and
153 		 * return the number of packets we've processed so far.
154 		 */
155 		if (p->break_loop) {
156 			if (n == 0) {
157 				p->break_loop = 0;
158 				return (-2);
159 			} else {
160 				p->bp = bp;
161 				p->cc = ep - bp;
162 				return (n);
163 			}
164 		}
165 		if (bp >= ep)
166 			break;
167 
168 		caplen = bhp->bh_caplen;
169 		hdrlen = bhp->bh_hdrlen;
170 
171 		/*
172 		 * XXX A bpf_hdr matches a pcap_pkthdr.
173 		 */
174 		(*callback)(user, (struct pcap_pkthdr*)bp, bp + hdrlen);
175 		bp += BPF_WORDALIGN(caplen + hdrlen);
176 		if (++n >= cnt && cnt > 0) {
177 			p->bp = bp;
178 			p->cc = ep - bp;
179 			return (n);
180 		}
181 	}
182 #undef bhp
183 	p->cc = 0;
184 	return (n);
185 }
186 
187 #ifdef HAVE_DAG_API
188 static int
pcap_read_win32_dag(pcap_t * p,int cnt,pcap_handler callback,u_char * user)189 pcap_read_win32_dag(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
190 {
191 	u_char *dp = NULL;
192 	int	packet_len = 0, caplen = 0;
193 	struct pcap_pkthdr	pcap_header;
194 	u_char *endofbuf;
195 	int n = 0;
196 	dag_record_t *header;
197 	unsigned erf_record_len;
198 	ULONGLONG ts;
199 	int cc;
200 	unsigned swt;
201 	unsigned dfp = p->adapter->DagFastProcess;
202 
203 	cc = p->cc;
204 	if (cc == 0) /* Get new packets only if we have processed all the ones of the previous read */
205 	{
206 	    /* Get new packets from the network */
207 		if(PacketReceivePacket(p->adapter, p->Packet, TRUE)==FALSE){
208 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "read error: PacketReceivePacket failed");
209 			return (-1);
210 		}
211 
212 		cc = p->Packet->ulBytesReceived;
213 		if(cc == 0)
214 			/* The timeout has expired but we no packets arrived */
215 			return 0;
216 		header = (dag_record_t*)p->adapter->DagBuffer;
217 	}
218 	else
219 		header = (dag_record_t*)p->bp;
220 
221 	endofbuf = (char*)header + cc;
222 
223 	/*
224 	 * Cycle through the packets
225 	 */
226 	do
227 	{
228 		erf_record_len = SWAPS(header->rlen);
229 		if((char*)header + erf_record_len > endofbuf)
230 			break;
231 
232 		/* Increase the number of captured packets */
233 		p->md.stat.ps_recv++;
234 
235 		/* Find the beginning of the packet */
236 		dp = ((u_char *)header) + dag_record_size;
237 
238 		/* Determine actual packet len */
239 		switch(header->type)
240 		{
241 		case TYPE_ATM:
242 			packet_len = ATM_SNAPLEN;
243 			caplen = ATM_SNAPLEN;
244 			dp += 4;
245 
246 			break;
247 
248 		case TYPE_ETH:
249 			swt = SWAPS(header->wlen);
250 			packet_len = swt - (p->md.dag_fcs_bits);
251 			caplen = erf_record_len - dag_record_size - 2;
252 			if (caplen > packet_len)
253 			{
254 				caplen = packet_len;
255 			}
256 			dp += 2;
257 
258 			break;
259 
260 		case TYPE_HDLC_POS:
261 			swt = SWAPS(header->wlen);
262 			packet_len = swt - (p->md.dag_fcs_bits);
263 			caplen = erf_record_len - dag_record_size;
264 			if (caplen > packet_len)
265 			{
266 				caplen = packet_len;
267 			}
268 
269 			break;
270 		}
271 
272 		if(caplen > p->snapshot)
273 			caplen = p->snapshot;
274 
275 		/*
276 		 * Has "pcap_breakloop()" been called?
277 		 * If so, return immediately - if we haven't read any
278 		 * packets, clear the flag and return -2 to indicate
279 		 * that we were told to break out of the loop, otherwise
280 		 * leave the flag set, so that the *next* call will break
281 		 * out of the loop without having read any packets, and
282 		 * return the number of packets we've processed so far.
283 		 */
284 		if (p->break_loop)
285 		{
286 			if (n == 0)
287 			{
288 				p->break_loop = 0;
289 				return (-2);
290 			}
291 			else
292 			{
293 				p->bp = (char*)header;
294 				p->cc = endofbuf - (char*)header;
295 				return (n);
296 			}
297 		}
298 
299 		if(!dfp)
300 		{
301 			/* convert between timestamp formats */
302 			ts = header->ts;
303 			pcap_header.ts.tv_sec = (int)(ts >> 32);
304 			ts = (ts & 0xffffffffi64) * 1000000;
305 			ts += 0x80000000; /* rounding */
306 			pcap_header.ts.tv_usec = (int)(ts >> 32);
307 			if (pcap_header.ts.tv_usec >= 1000000) {
308 				pcap_header.ts.tv_usec -= 1000000;
309 				pcap_header.ts.tv_sec++;
310 			}
311 		}
312 
313 		/* No underlaying filtering system. We need to filter on our own */
314 		if (p->fcode.bf_insns)
315 		{
316 			if (bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen) == 0)
317 			{
318 				/* Move to next packet */
319 				header = (dag_record_t*)((char*)header + erf_record_len);
320 				continue;
321 			}
322 		}
323 
324 		/* Fill the header for the user suppplied callback function */
325 		pcap_header.caplen = caplen;
326 		pcap_header.len = packet_len;
327 
328 		/* Call the callback function */
329 		(*callback)(user, &pcap_header, dp);
330 
331 		/* Move to next packet */
332 		header = (dag_record_t*)((char*)header + erf_record_len);
333 
334 		/* Stop if the number of packets requested by user has been reached*/
335 		if (++n >= cnt && cnt > 0)
336 		{
337 			p->bp = (char*)header;
338 			p->cc = endofbuf - (char*)header;
339 			return (n);
340 		}
341 	}
342 	while((u_char*)header < endofbuf);
343 
344   return 1;
345 }
346 #endif /* HAVE_DAG_API */
347 
348 /* Send a packet to the network */
349 static int
pcap_inject_win32(pcap_t * p,const void * buf,size_t size)350 pcap_inject_win32(pcap_t *p, const void *buf, size_t size){
351 	LPPACKET PacketToSend;
352 
353 	PacketToSend=PacketAllocatePacket();
354 
355 	if (PacketToSend == NULL)
356 	{
357 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send error: PacketAllocatePacket failed");
358 		return -1;
359 	}
360 
361 	PacketInitPacket(PacketToSend,(PVOID)buf,size);
362 	if(PacketSendPacket(p->adapter,PacketToSend,TRUE) == FALSE){
363 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send error: PacketSendPacket failed");
364 		PacketFreePacket(PacketToSend);
365 		return -1;
366 	}
367 
368 	PacketFreePacket(PacketToSend);
369 
370 	/*
371 	 * We assume it all got sent if "PacketSendPacket()" succeeded.
372 	 * "pcap_inject()" is expected to return the number of bytes
373 	 * sent.
374 	 */
375 	return size;
376 }
377 
378 static void
pcap_close_win32(pcap_t * p)379 pcap_close_win32(pcap_t *p)
380 {
381 	pcap_close_common(p);
382 	if (p->adapter != NULL) {
383 		PacketCloseAdapter(p->adapter);
384 		p->adapter = NULL;
385 	}
386 	if (p->Packet) {
387 		PacketFreePacket(p->Packet);
388 		p->Packet = NULL;
389 	}
390 }
391 
392 pcap_t *
pcap_open_live(const char * device,int snaplen,int promisc,int to_ms,char * ebuf)393 pcap_open_live(const char *device, int snaplen, int promisc, int to_ms,
394     char *ebuf)
395 {
396 	register pcap_t *p;
397 	NetType type;
398 
399 	/* Init WinSock */
400 	wsockinit();
401 
402 	p = (pcap_t *)malloc(sizeof(*p));
403 	if (p == NULL)
404 	{
405 		snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno));
406 		return (NULL);
407 	}
408 	memset(p, 0, sizeof(*p));
409 	p->adapter=NULL;
410 
411 	p->adapter = PacketOpenAdapter((char*)device);
412 
413 	if (p->adapter == NULL)
414 	{
415 		free(p);
416 		/* Adapter detected but we are not able to open it. Return failure. */
417 		snprintf(ebuf, PCAP_ERRBUF_SIZE, "Error opening adapter: %s", pcap_win32strerror());
418 		return NULL;
419 	}
420 
421 	/*get network type*/
422 	if(PacketGetNetType (p->adapter,&type) == FALSE)
423 	{
424 		snprintf(ebuf, PCAP_ERRBUF_SIZE, "Cannot determine the network type: %s", pcap_win32strerror());
425 		goto bad;
426 	}
427 
428 	/*Set the linktype*/
429 	switch (type.LinkType)
430 	{
431 	case NdisMediumWan:
432 		p->linktype = DLT_EN10MB;
433 		break;
434 
435 	case NdisMedium802_3:
436 		p->linktype = DLT_EN10MB;
437 		/*
438 		 * This is (presumably) a real Ethernet capture; give it a
439 		 * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
440 		 * that an application can let you choose it, in case you're
441 		 * capturing DOCSIS traffic that a Cisco Cable Modem
442 		 * Termination System is putting out onto an Ethernet (it
443 		 * doesn't put an Ethernet header onto the wire, it puts raw
444 		 * DOCSIS frames out on the wire inside the low-level
445 		 * Ethernet framing).
446 		 */
447 		p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
448 		/*
449 		 * If that fails, just leave the list empty.
450 		 */
451 		if (p->dlt_list != NULL) {
452 			p->dlt_list[0] = DLT_EN10MB;
453 			p->dlt_list[1] = DLT_DOCSIS;
454 			p->dlt_count = 2;
455 		}
456 		break;
457 
458 	case NdisMediumFddi:
459 		p->linktype = DLT_FDDI;
460 		break;
461 
462 	case NdisMedium802_5:
463 		p->linktype = DLT_IEEE802;
464 		break;
465 
466 	case NdisMediumArcnetRaw:
467 		p->linktype = DLT_ARCNET;
468 		break;
469 
470 	case NdisMediumArcnet878_2:
471 		p->linktype = DLT_ARCNET;
472 		break;
473 
474 	case NdisMediumAtm:
475 		p->linktype = DLT_ATM_RFC1483;
476 		break;
477 
478 	case NdisMediumCHDLC:
479 		p->linktype = DLT_CHDLC;
480 		break;
481 
482 	case NdisMediumPPPSerial:
483 		p->linktype = DLT_PPP_SERIAL;
484 		break;
485 
486 	case NdisMediumNull:
487 		p->linktype = DLT_NULL;
488 		break;
489 
490 	case NdisMediumBare80211:
491 		p->linktype = DLT_IEEE802_11;
492 		break;
493 
494 	case NdisMediumRadio80211:
495 		p->linktype = DLT_IEEE802_11_RADIO;
496 		break;
497 
498 	case NdisMediumPpi:
499 		p->linktype = DLT_PPI;
500 		break;
501 
502 	default:
503 		p->linktype = DLT_EN10MB;			/*an unknown adapter is assumed to be ethernet*/
504 		break;
505 	}
506 
507 	/* Set promiscuous mode */
508 	if (promisc)
509 	{
510 
511 		if (PacketSetHwFilter(p->adapter,NDIS_PACKET_TYPE_PROMISCUOUS) == FALSE)
512 		{
513 			snprintf(ebuf, PCAP_ERRBUF_SIZE, "failed to set hardware filter to promiscuous mode");
514 			goto bad;
515 		}
516 	}
517 	else
518 	{
519 		if (PacketSetHwFilter(p->adapter,NDIS_PACKET_TYPE_ALL_LOCAL) == FALSE)
520 		{
521 			snprintf(ebuf, PCAP_ERRBUF_SIZE, "failed to set hardware filter to non-promiscuous mode");
522 			goto bad;
523 		}
524 	}
525 
526 	/* Set the buffer size */
527 	p->bufsize = PcapBufSize;
528 
529 	/* Store the timeout. Used by pcap_setnonblock() */
530 	p->timeout= to_ms;
531 
532 	/* allocate Packet structure used during the capture */
533 	if((p->Packet = PacketAllocatePacket())==NULL)
534 	{
535 		snprintf(ebuf, PCAP_ERRBUF_SIZE, "failed to allocate the PACKET structure");
536 		goto bad;
537 	}
538 
539 	if(!(p->adapter->Flags & INFO_FLAG_DAG_CARD))
540 	{
541 	/*
542 	 * Traditional Adapter
543 	 */
544 
545 		p->buffer = (u_char *)malloc(PcapBufSize);
546 		if (p->buffer == NULL)
547 		{
548 			snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno));
549 			goto bad;
550 		}
551 
552 		PacketInitPacket(p->Packet,(BYTE*)p->buffer,p->bufsize);
553 
554 		p->snapshot = snaplen;
555 
556 		/* allocate the standard buffer in the driver */
557 		if(PacketSetBuff( p->adapter, SIZE_BUF)==FALSE)
558 		{
559 			snprintf(ebuf, PCAP_ERRBUF_SIZE,"driver error: not enough memory to allocate the kernel buffer\n");
560 			goto bad;
561 		}
562 
563 		/* tell the driver to copy the buffer only if it contains at least 16K */
564 		if(PacketSetMinToCopy(p->adapter,16000)==FALSE)
565 		{
566 			snprintf(ebuf, PCAP_ERRBUF_SIZE,"Error calling PacketSetMinToCopy: %s\n", pcap_win32strerror());
567 			goto bad;
568 		}
569 	}
570 	else
571 #ifdef HAVE_DAG_API
572 	{
573 	/*
574 	 * Dag Card
575 	 */
576 		LONG	status;
577 		HKEY	dagkey;
578 		DWORD	lptype;
579 		DWORD	lpcbdata;
580 		int		postype = 0;
581 		char	keyname[512];
582 
583 		snprintf(keyname, sizeof(keyname), "%s\\CardParams\\%s",
584 			"SYSTEM\\CurrentControlSet\\Services\\DAG",
585 			strstr(_strlwr((char*)device), "dag"));
586 		do
587 		{
588 			status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, keyname, 0, KEY_READ, &dagkey);
589 			if(status != ERROR_SUCCESS)
590 				break;
591 
592 			status = RegQueryValueEx(dagkey,
593 				"PosType",
594 				NULL,
595 				&lptype,
596 				(char*)&postype,
597 				&lpcbdata);
598 
599 			if(status != ERROR_SUCCESS)
600 			{
601 				postype = 0;
602 			}
603 
604 			RegCloseKey(dagkey);
605 		}
606 		while(FALSE);
607 
608 
609 		p->snapshot = PacketSetSnapLen(p->adapter, snaplen);
610 
611 		/* Set the length of the FCS associated to any packet. This value
612 		 * will be subtracted to the packet length */
613 		p->md.dag_fcs_bits = p->adapter->DagFcsLen;
614 	}
615 #else
616 	goto bad;
617 #endif /* HAVE_DAG_API */
618 
619 	PacketSetReadTimeout(p->adapter, to_ms);
620 
621 #ifdef HAVE_DAG_API
622 	if(p->adapter->Flags & INFO_FLAG_DAG_CARD)
623 	{
624 		/* install dag specific handlers for read and setfilter */
625 		p->read_op = pcap_read_win32_dag;
626 		p->setfilter_op = pcap_setfilter_win32_dag;
627 	}
628 	else
629 	{
630 #endif /* HAVE_DAG_API */
631 		/* install traditional npf handlers for read and setfilter */
632 		p->read_op = pcap_read_win32_npf;
633 		p->setfilter_op = pcap_setfilter_win32_npf;
634 #ifdef HAVE_DAG_API
635 	}
636 #endif /* HAVE_DAG_API */
637 	p->setdirection_op = NULL;	/* Not implemented. */
638 	    /* XXX - can this be implemented on some versions of Windows? */
639 	p->inject_op = pcap_inject_win32;
640 	p->set_datalink_op = NULL;	/* can't change data link type */
641 	p->getnonblock_op = pcap_getnonblock_win32;
642 	p->setnonblock_op = pcap_setnonblock_win32;
643 	p->stats_op = pcap_stats_win32;
644 	p->close_op = pcap_close_win32;
645 
646 	return (p);
647 bad:
648 	if (p->adapter)
649 	    PacketCloseAdapter(p->adapter);
650 	if (p->buffer != NULL)
651 		free(p->buffer);
652 	if(p->Packet)
653 		PacketFreePacket(p->Packet);
654 	/*
655 	 * Get rid of any link-layer type list we allocated.
656 	 */
657 	if (p->dlt_list != NULL)
658 		free(p->dlt_list);
659 	free(p);
660 	return (NULL);
661 }
662 
663 
664 static int
pcap_setfilter_win32_npf(pcap_t * p,struct bpf_program * fp)665 pcap_setfilter_win32_npf(pcap_t *p, struct bpf_program *fp)
666 {
667 	if(PacketSetBpf(p->adapter,fp)==FALSE){
668 		/*
669 		 * Kernel filter not installed.
670 		 * XXX - fall back on userland filtering, as is done
671 		 * on other platforms?
672 		 */
673 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Driver error: cannot set bpf filter: %s", pcap_win32strerror());
674 		return (-1);
675 	}
676 
677 	/*
678 	 * Discard any previously-received packets, as they might have
679 	 * passed whatever filter was formerly in effect, but might
680 	 * not pass this filter (BIOCSETF discards packets buffered
681 	 * in the kernel, so you can lose packets in any case).
682 	 */
683 	p->cc = 0;
684 	return (0);
685 }
686 
687 /*
688  * We filter at user level, since the kernel driver does't process the packets
689  */
690 static int
pcap_setfilter_win32_dag(pcap_t * p,struct bpf_program * fp)691 pcap_setfilter_win32_dag(pcap_t *p, struct bpf_program *fp) {
692 
693 	if(!fp)
694 	{
695 		strncpy(p->errbuf, "setfilter: No filter specified", sizeof(p->errbuf));
696 		return -1;
697 	}
698 
699 	/* Install a user level filter */
700 	if (install_bpf_program(p, fp) < 0)
701 	{
702 		snprintf(p->errbuf, sizeof(p->errbuf),
703 			"setfilter, unable to install the filter: %s", pcap_strerror(errno));
704 		return -1;
705 	}
706 
707 	p->md.use_bpf = 0;
708 
709 	return (0);
710 }
711 
712 static int
pcap_getnonblock_win32(pcap_t * p,char * errbuf)713 pcap_getnonblock_win32(pcap_t *p, char *errbuf)
714 {
715 	/*
716 	 * XXX - if there were a PacketGetReadTimeout() call, we
717 	 * would use it, and return 1 if the timeout is -1
718 	 * and 0 otherwise.
719 	 */
720 	return (p->nonblock);
721 }
722 
723 static int
pcap_setnonblock_win32(pcap_t * p,int nonblock,char * errbuf)724 pcap_setnonblock_win32(pcap_t *p, int nonblock, char *errbuf)
725 {
726 	int newtimeout;
727 
728 	if (nonblock) {
729 		/*
730 		 * Set the read timeout to -1 for non-blocking mode.
731 		 */
732 		newtimeout = -1;
733 	} else {
734 		/*
735 		 * Restore the timeout set when the device was opened.
736 		 * (Note that this may be -1, in which case we're not
737 		 * really leaving non-blocking mode.)
738 		 */
739 		newtimeout = p->timeout;
740 	}
741 	if (!PacketSetReadTimeout(p->adapter, newtimeout)) {
742 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
743 		    "PacketSetReadTimeout: %s", pcap_win32strerror());
744 		return (-1);
745 	}
746 	p->nonblock = (newtimeout == -1);
747 	return (0);
748 }
749 
750 /* Set the driver working mode */
751 int
pcap_setmode(pcap_t * p,int mode)752 pcap_setmode(pcap_t *p, int mode){
753 
754 	if (p->adapter==NULL)
755 	{
756 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "impossible to set mode while reading from a file");
757 		return -1;
758 	}
759 
760 	if(PacketSetMode(p->adapter,mode)==FALSE)
761 	{
762 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: working mode not recognized");
763 		return -1;
764 	}
765 
766 	return 0;
767 }
768 
769 /* Set the dimension of the kernel-level capture buffer */
770 int
pcap_setbuff(pcap_t * p,int dim)771 pcap_setbuff(pcap_t *p, int dim)
772 {
773 	if (p->adapter==NULL)
774 	{
775 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "The kernel buffer size cannot be set while reading from a file");
776 		return -1;
777 	}
778 
779 	if(PacketSetBuff(p->adapter,dim)==FALSE)
780 	{
781 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: not enough memory to allocate the kernel buffer");
782 		return -1;
783 	}
784 	return 0;
785 }
786 
787 /*set the minimum amount of data that will release a read call*/
788 int
pcap_setmintocopy(pcap_t * p,int size)789 pcap_setmintocopy(pcap_t *p, int size)
790 {
791 	if (p->adapter==NULL)
792 	{
793 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Impossible to set the mintocopy parameter on an offline capture");
794 		return -1;
795 	}
796 
797 	if(PacketSetMinToCopy(p->adapter, size)==FALSE)
798 	{
799 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: unable to set the requested mintocopy size");
800 		return -1;
801 	}
802 	return 0;
803 }
804