1/* 2 * Copyright (c) 1999 - 2005 NetGroup, Politecnico di Torino (Italy) 3 * Copyright (c) 2005 - 2006 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 35static const char rcsid[] _U_ = 36 "@(#) $Header: /tcpdump/master/libpcap/pcap-win32.c,v 1.25.2.5 2006/08/09 19:18:41 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__ 47int* _errno(); 48#define errno (*_errno()) 49#endif /* __MINGW32__ */ 50 51static int pcap_setfilter_win32_npf(pcap_t *, struct bpf_program *); 52static int pcap_setfilter_win32_dag(pcap_t *, struct bpf_program *); 53static int pcap_getnonblock_win32(pcap_t *, char *); 54static 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 */ 66struct 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 */ 75int 76wsockinit() 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 91static int 92pcap_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 103static int 104pcap_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 188static int 189pcap_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 */ 349static int 350pcap_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 378static void 379pcap_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 392pcap_t * 393pcap_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 default: 499 p->linktype = DLT_EN10MB; /*an unknown adapter is assumed to be ethernet*/ 500 break; 501 } 502 503 /* Set promisquous mode */ 504 if (promisc) PacketSetHwFilter(p->adapter,NDIS_PACKET_TYPE_PROMISCUOUS); 505 else PacketSetHwFilter(p->adapter,NDIS_PACKET_TYPE_ALL_LOCAL); 506 507 /* Set the buffer size */ 508 p->bufsize = PcapBufSize; 509 510 /* Store the timeout. Used by pcap_setnonblock() */ 511 p->timeout= to_ms; 512 513 /* allocate Packet structure used during the capture */ 514 if((p->Packet = PacketAllocatePacket())==NULL) 515 { 516 snprintf(ebuf, PCAP_ERRBUF_SIZE, "failed to allocate the PACKET structure"); 517 goto bad; 518 } 519 520 if(!(p->adapter->Flags & INFO_FLAG_DAG_CARD)) 521 { 522 /* 523 * Traditional Adapter 524 */ 525 526 p->buffer = (u_char *)malloc(PcapBufSize); 527 if (p->buffer == NULL) 528 { 529 snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno)); 530 goto bad; 531 } 532 533 PacketInitPacket(p->Packet,(BYTE*)p->buffer,p->bufsize); 534 535 p->snapshot = snaplen; 536 537 /* allocate the standard buffer in the driver */ 538 if(PacketSetBuff( p->adapter, SIZE_BUF)==FALSE) 539 { 540 snprintf(ebuf, PCAP_ERRBUF_SIZE,"driver error: not enough memory to allocate the kernel buffer\n"); 541 goto bad; 542 } 543 544 /* tell the driver to copy the buffer only if it contains at least 16K */ 545 if(PacketSetMinToCopy(p->adapter,16000)==FALSE) 546 { 547 snprintf(ebuf, PCAP_ERRBUF_SIZE,"Error calling PacketSetMinToCopy: %s\n", pcap_win32strerror()); 548 goto bad; 549 } 550 } 551 else 552#ifdef HAVE_DAG_API 553 { 554 /* 555 * Dag Card 556 */ 557 LONG status; 558 HKEY dagkey; 559 DWORD lptype; 560 DWORD lpcbdata; 561 int postype = 0; 562 char keyname[512]; 563 564 snprintf(keyname, sizeof(keyname), "%s\\CardParams\\%s", 565 "SYSTEM\\CurrentControlSet\\Services\\DAG", 566 strstr(_strlwr((char*)device), "dag")); 567 do 568 { 569 status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, keyname, 0, KEY_READ, &dagkey); 570 if(status != ERROR_SUCCESS) 571 break; 572 573 status = RegQueryValueEx(dagkey, 574 "PosType", 575 NULL, 576 &lptype, 577 (char*)&postype, 578 &lpcbdata); 579 580 if(status != ERROR_SUCCESS) 581 { 582 postype = 0; 583 } 584 585 RegCloseKey(dagkey); 586 } 587 while(FALSE); 588 589 590 p->snapshot = PacketSetSnapLen(p->adapter, snaplen); 591 592 /* Set the length of the FCS associated to any packet. This value 593 * will be subtracted to the packet length */ 594 p->md.dag_fcs_bits = p->adapter->DagFcsLen; 595 } 596#else 597 goto bad; 598#endif /* HAVE_DAG_API */ 599 600 PacketSetReadTimeout(p->adapter, to_ms); 601 602#ifdef HAVE_DAG_API 603 if(p->adapter->Flags & INFO_FLAG_DAG_CARD) 604 { 605 /* install dag specific handlers for read and setfilter */ 606 p->read_op = pcap_read_win32_dag; 607 p->setfilter_op = pcap_setfilter_win32_dag; 608 } 609 else 610 { 611#endif /* HAVE_DAG_API */ 612 /* install traditional npf handlers for read and setfilter */ 613 p->read_op = pcap_read_win32_npf; 614 p->setfilter_op = pcap_setfilter_win32_npf; 615#ifdef HAVE_DAG_API 616 } 617#endif /* HAVE_DAG_API */ 618 p->setdirection_op = NULL; /* Not implemented. */ 619 /* XXX - can this be implemented on some versions of Windows? */ 620 p->inject_op = pcap_inject_win32; 621 p->set_datalink_op = NULL; /* can't change data link type */ 622 p->getnonblock_op = pcap_getnonblock_win32; 623 p->setnonblock_op = pcap_setnonblock_win32; 624 p->stats_op = pcap_stats_win32; 625 p->close_op = pcap_close_win32; 626 627 return (p); 628bad: 629 if (p->adapter) 630 PacketCloseAdapter(p->adapter); 631 if (p->buffer != NULL) 632 free(p->buffer); 633 if(p->Packet) 634 PacketFreePacket(p->Packet); 635 /* 636 * Get rid of any link-layer type list we allocated. 637 */ 638 if (p->dlt_list != NULL) 639 free(p->dlt_list); 640 free(p); 641 return (NULL); 642} 643 644 645static int 646pcap_setfilter_win32_npf(pcap_t *p, struct bpf_program *fp) 647{ 648 if(PacketSetBpf(p->adapter,fp)==FALSE){ 649 /* 650 * Kernel filter not installed. 651 * XXX - fall back on userland filtering, as is done 652 * on other platforms? 653 */ 654 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Driver error: cannot set bpf filter: %s", pcap_win32strerror()); 655 return (-1); 656 } 657 658 /* 659 * Discard any previously-received packets, as they might have 660 * passed whatever filter was formerly in effect, but might 661 * not pass this filter (BIOCSETF discards packets buffered 662 * in the kernel, so you can lose packets in any case). 663 */ 664 p->cc = 0; 665 return (0); 666} 667 668/* 669 * We filter at user level, since the kernel driver does't process the packets 670 */ 671static int 672pcap_setfilter_win32_dag(pcap_t *p, struct bpf_program *fp) { 673 674 if(!fp) 675 { 676 strncpy(p->errbuf, "setfilter: No filter specified", sizeof(p->errbuf)); 677 return -1; 678 } 679 680 /* Install a user level filter */ 681 if (install_bpf_program(p, fp) < 0) 682 { 683 snprintf(p->errbuf, sizeof(p->errbuf), 684 "setfilter, unable to install the filter: %s", pcap_strerror(errno)); 685 return -1; 686 } 687 688 p->md.use_bpf = 0; 689 690 return (0); 691} 692 693static int 694pcap_getnonblock_win32(pcap_t *p, char *errbuf) 695{ 696 /* 697 * XXX - if there were a PacketGetReadTimeout() call, we 698 * would use it, and return 1 if the timeout is -1 699 * and 0 otherwise. 700 */ 701 return (p->nonblock); 702} 703 704static int 705pcap_setnonblock_win32(pcap_t *p, int nonblock, char *errbuf) 706{ 707 int newtimeout; 708 709 if (nonblock) { 710 /* 711 * Set the read timeout to -1 for non-blocking mode. 712 */ 713 newtimeout = -1; 714 } else { 715 /* 716 * Restore the timeout set when the device was opened. 717 * (Note that this may be -1, in which case we're not 718 * really leaving non-blocking mode.) 719 */ 720 newtimeout = p->timeout; 721 } 722 if (!PacketSetReadTimeout(p->adapter, newtimeout)) { 723 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 724 "PacketSetReadTimeout: %s", pcap_win32strerror()); 725 return (-1); 726 } 727 p->nonblock = (newtimeout == -1); 728 return (0); 729} 730 731/* Set the driver working mode */ 732int 733pcap_setmode(pcap_t *p, int mode){ 734 735 if (p->adapter==NULL) 736 { 737 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "impossible to set mode while reading from a file"); 738 return -1; 739 } 740 741 if(PacketSetMode(p->adapter,mode)==FALSE) 742 { 743 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: working mode not recognized"); 744 return -1; 745 } 746 747 return 0; 748} 749 750/* Set the dimension of the kernel-level capture buffer */ 751int 752pcap_setbuff(pcap_t *p, int dim) 753{ 754 if (p->adapter==NULL) 755 { 756 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "The kernel buffer size cannot be set while reading from a file"); 757 return -1; 758 } 759 760 if(PacketSetBuff(p->adapter,dim)==FALSE) 761 { 762 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: not enough memory to allocate the kernel buffer"); 763 return -1; 764 } 765 return 0; 766} 767 768/*set the minimum amount of data that will release a read call*/ 769int 770pcap_setmintocopy(pcap_t *p, int size) 771{ 772 if (p->adapter==NULL) 773 { 774 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Impossible to set the mintocopy parameter on an offline capture"); 775 return -1; 776 } 777 778 if(PacketSetMinToCopy(p->adapter, size)==FALSE) 779 { 780 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: unable to set the requested mintocopy size"); 781 return -1; 782 } 783 return 0; 784} 785