The Tcpdump Group git mirrors - libpcap/blob - pcap-win32.c

   1 /*
   2  * Copyright (c) 1999 - 2005 NetGroup, Politecnico di Torino (Italy)
   3  * Copyright (c) 2005 - 2008 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 #include <pcap-int.h>
  35 #include <Packet32.h>
  36 #ifdef __MINGW32__
  37 #ifdef __MINGW64__
  38 #include <ntddndis.h>
  39 #else  /*__MINGW64__*/
  40 #include <ddk/ntddndis.h>
  41 #include <ddk/ndis.h>
  42 #endif /*__MINGW64__*/
  43 #else /*__MINGW32__*/
  44 #include <ntddndis.h>
  45 #endif /*__MINGW32__*/
  46 #ifdef HAVE_DAG_API
  47 #include <dagnew.h>
  48 #include <dagapi.h>
  49 #endif /* HAVE_DAG_API */
  50 #ifdef __MINGW32__
  51 int* _errno();
  52 #define errno (*_errno())
  53 #endif /* __MINGW32__ */
  54
  55 static int pcap_setfilter_win32_npf(pcap_t *, struct bpf_program *);
  56 static int pcap_setfilter_win32_dag(pcap_t *, struct bpf_program *);
  57 static int pcap_getnonblock_win32(pcap_t *, char *);
  58 static int pcap_setnonblock_win32(pcap_t *, int, char *);
  59
  60 /*dimension of the buffer in the pcap_t structure*/
  61 #define WIN32_DEFAULT_USER_BUFFER_SIZE 256000
  62
  63 /*dimension of the buffer in the kernel driver NPF */
  64 #define WIN32_DEFAULT_KERNEL_BUFFER_SIZE 1000000
  65
  66 /* Equivalent to ntohs(), but a lot faster under Windows */
  67 #define SWAPS(_X) ((_X & 0xff) << 8) | (_X >> 8)
  68
  69 /*
  70  * Private data for capturing on WinPcap devices.
  71  */
  72 struct pcap_win {
  73         int nonblock;
  74
  75         int filtering_in_kernel; /* using kernel filter */
  76
  77 #ifdef HAVE_DAG_API
  78         int     dag_fcs_bits;   /* Number of checksum bits from link layer */
  79 #endif
  80 };
  81
  82 /*
  83  * Header that the WinPcap driver associates to the packets.
  84  * Once was in bpf.h
  85  */
  86 struct bpf_hdr {
  87         struct timeval  bh_tstamp;      /* time stamp */
  88         bpf_u_int32     bh_caplen;      /* length of captured portion */
  89         bpf_u_int32     bh_datalen;     /* original length of packet */
  90         u_short         bh_hdrlen;      /* length of bpf header (this struct
  91                                            plus alignment padding) */
  92 };
  93
  94 CRITICAL_SECTION g_PcapCompileCriticalSection;
  95
  96 BOOL WINAPI DllMain(
  97   HANDLE hinstDLL,
  98   DWORD dwReason,
  99   LPVOID lpvReserved
 100 )
 101 {
 102         if (dwReason == DLL_PROCESS_ATTACH)
 103         {
 104                 InitializeCriticalSection(&g_PcapCompileCriticalSection);
 105         }
 106
 107         return TRUE;
 108 }
 109
 110 /* Start winsock */
 111 int
 112 wsockinit()
 113 {
 114         WORD wVersionRequested;
 115         WSADATA wsaData;
 116         static int err = -1;
 117         static int done = 0;
 118
 119         if (done)
 120                 return err;
 121
 122         wVersionRequested = MAKEWORD( 1, 1);
 123         err = WSAStartup( wVersionRequested, &wsaData );
 124         atexit ((void(*)(void))WSACleanup);
 125         InitializeCriticalSection(&g_PcapCompileCriticalSection);
 126         done = 1;
 127
 128         if ( err != 0 )
 129                 err = -1;
 130         return err;
 131 }
 132
 133 int pcap_wsockinit()
 134 {
 135        return wsockinit();
 136 }
 137
 138 static int
 139 pcap_stats_win32(pcap_t *p, struct pcap_stat *ps)
 140 {
 141
 142         if(PacketGetStats(p->adapter, (struct bpf_stat*)ps) != TRUE){
 143                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "PacketGetStats error: %s", pcap_win32strerror());
 144                 return -1;
 145         }
 146
 147         return 0;
 148 }
 149
 150 /* Set the dimension of the kernel-level capture buffer */
 151 static int
 152 pcap_setbuff_win32(pcap_t *p, int dim)
 153 {
 154         if(PacketSetBuff(p->adapter,dim)==FALSE)
 155         {
 156                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: not enough memory to allocate the kernel buffer");
 157                 return -1;
 158         }
 159         return 0;
 160 }
 161
 162 /* Set the driver working mode */
 163 static int
 164 pcap_setmode_win32(pcap_t *p, int mode)
 165 {
 166         if(PacketSetMode(p->adapter,mode)==FALSE)
 167         {
 168                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: working mode not recognized");
 169                 return -1;
 170         }
 171
 172         return 0;
 173 }
 174
 175 /*set the minimum amount of data that will release a read call*/
 176 static int
 177 pcap_setmintocopy_win32(pcap_t *p, int size)
 178 {
 179         if(PacketSetMinToCopy(p->adapter, size)==FALSE)
 180         {
 181                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: unable to set the requested mintocopy size");
 182                 return -1;
 183         }
 184         return 0;
 185 }
 186
 187 /*return the Adapter for a pcap_t*/
 188 static Adapter *
 189 pcap_getadapter_win32(pcap_t *p)
 190 {
 191         return p->adapter;
 192 }
 193
 194 static int
 195 pcap_read_win32_npf(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
 196 {
 197         int cc;
 198         int n = 0;
 199         register u_char *bp, *ep;
 200         u_char *datap;
 201         struct pcap_win *pw = p->priv;
 202
 203         cc = p->cc;
 204         if (p->cc == 0) {
 205                 /*
 206                  * Has "pcap_breakloop()" been called?
 207                  */
 208                 if (p->break_loop) {
 209                         /*
 210                          * Yes - clear the flag that indicates that it
 211                          * has, and return PCAP_ERROR_BREAK to indicate
 212                          * that we were told to break out of the loop.
 213                          */
 214                         p->break_loop = 0;
 215                         return (PCAP_ERROR_BREAK);
 216                 }
 217
 218             /* capture the packets */
 219                 if(PacketReceivePacket(p->adapter,p->Packet,TRUE)==FALSE){
 220                         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "read error: PacketReceivePacket failed");
 221                         return (PCAP_ERROR);
 222                 }
 223
 224                 cc = p->Packet->ulBytesReceived;
 225
 226                 bp = p->Packet->Buffer;
 227         }
 228         else
 229                 bp = p->bp;
 230
 231         /*
 232          * Loop through each packet.
 233          */
 234 #define bhp ((struct bpf_hdr *)bp)
 235         ep = bp + cc;
 236         while (1) {
 237                 register int caplen, hdrlen;
 238
 239                 /*
 240                  * Has "pcap_breakloop()" been called?
 241                  * If so, return immediately - if we haven't read any
 242                  * packets, clear the flag and return PCAP_ERROR_BREAK
 243                  * to indicate that we were told to break out of the loop,
 244                  * otherwise leave the flag set, so that the *next* call
 245                  * will break out of the loop without having read any
 246                  * packets, and return the number of packets we've
 247                  * processed so far.
 248                  */
 249                 if (p->break_loop) {
 250                         if (n == 0) {
 251                                 p->break_loop = 0;
 252                                 return (PCAP_ERROR_BREAK);
 253                         } else {
 254                                 p->bp = bp;
 255                                 p->cc = ep - bp;
 256                                 return (n);
 257                         }
 258                 }
 259                 if (bp >= ep)
 260                         break;
 261
 262                 caplen = bhp->bh_caplen;
 263                 hdrlen = bhp->bh_hdrlen;
 264                 datap = bp + hdrlen;
 265
 266                 /*
 267                  * Short-circuit evaluation: if using BPF filter
 268                  * in kernel, no need to do it now - we already know
 269                  * the packet passed the filter.
 270                  *
 271                  * XXX - bpf_filter() should always return TRUE if
 272                  * handed a null pointer for the program, but it might
 273                  * just try to "run" the filter, so we check here.
 274                  */
 275                 if (pw->filtering_in_kernel ||
 276                     p->fcode.bf_insns == NULL ||
 277                     bpf_filter(p->fcode.bf_insns, datap, bhp->bh_datalen, caplen)) {
 278                         /*
 279                          * XXX A bpf_hdr matches a pcap_pkthdr.
 280                          */
 281                         (*callback)(user, (struct pcap_pkthdr*)bp, datap);
 282                         bp += Packet_WORDALIGN(caplen + hdrlen);
 283                         if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {
 284                                 p->bp = bp;
 285                                 p->cc = ep - bp;
 286                                 return (n);
 287                         }
 288                 } else {
 289                         /*
 290                          * Skip this packet.
 291                          */
 292                         bp += Packet_WORDALIGN(caplen + hdrlen);
 293                 }
 294         }
 295 #undef bhp
 296         p->cc = 0;
 297         return (n);
 298 }
 299
 300 #ifdef HAVE_DAG_API
 301 static int
 302 pcap_read_win32_dag(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
 303 {
 304         struct pcap_win *pw = p->priv;
 305         u_char *dp = NULL;
 306         int     packet_len = 0, caplen = 0;
 307         struct pcap_pkthdr      pcap_header;
 308         u_char *endofbuf;
 309         int n = 0;
 310         dag_record_t *header;
 311         unsigned erf_record_len;
 312         ULONGLONG ts;
 313         int cc;
 314         unsigned swt;
 315         unsigned dfp = p->adapter->DagFastProcess;
 316
 317         cc = p->cc;
 318         if (cc == 0) /* Get new packets only if we have processed all the ones of the previous read */
 319         {
 320             /* Get new packets from the network */
 321                 if(PacketReceivePacket(p->adapter, p->Packet, TRUE)==FALSE){
 322                         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "read error: PacketReceivePacket failed");
 323                         return (-1);
 324                 }
 325
 326                 cc = p->Packet->ulBytesReceived;
 327                 if(cc == 0)
 328                         /* The timeout has expired but we no packets arrived */
 329                         return 0;
 330                 header = (dag_record_t*)p->adapter->DagBuffer;
 331         }
 332         else
 333                 header = (dag_record_t*)p->bp;
 334
 335         endofbuf = (char*)header + cc;
 336
 337         /*
 338          * Cycle through the packets
 339          */
 340         do
 341         {
 342                 erf_record_len = SWAPS(header->rlen);
 343                 if((char*)header + erf_record_len > endofbuf)
 344                         break;
 345
 346                 /* Increase the number of captured packets */
 347                 pw->stat.ps_recv++;
 348
 349                 /* Find the beginning of the packet */
 350                 dp = ((u_char *)header) + dag_record_size;
 351
 352                 /* Determine actual packet len */
 353                 switch(header->type)
 354                 {
 355                 case TYPE_ATM:
 356                         packet_len = ATM_SNAPLEN;
 357                         caplen = ATM_SNAPLEN;
 358                         dp += 4;
 359
 360                         break;
 361
 362                 case TYPE_ETH:
 363                         swt = SWAPS(header->wlen);
 364                         packet_len = swt - (pw->dag_fcs_bits);
 365                         caplen = erf_record_len - dag_record_size - 2;
 366                         if (caplen > packet_len)
 367                         {
 368                                 caplen = packet_len;
 369                         }
 370                         dp += 2;
 371
 372                         break;
 373
 374                 case TYPE_HDLC_POS:
 375                         swt = SWAPS(header->wlen);
 376                         packet_len = swt - (pw->dag_fcs_bits);
 377                         caplen = erf_record_len - dag_record_size;
 378                         if (caplen > packet_len)
 379                         {
 380                                 caplen = packet_len;
 381                         }
 382
 383                         break;
 384                 }
 385
 386                 if(caplen > p->snapshot)
 387                         caplen = p->snapshot;
 388
 389                 /*
 390                  * Has "pcap_breakloop()" been called?
 391                  * If so, return immediately - if we haven't read any
 392                  * packets, clear the flag and return -2 to indicate
 393                  * that we were told to break out of the loop, otherwise
 394                  * leave the flag set, so that the *next* call will break
 395                  * out of the loop without having read any packets, and
 396                  * return the number of packets we've processed so far.
 397                  */
 398                 if (p->break_loop)
 399                 {
 400                         if (n == 0)
 401                         {
 402                                 p->break_loop = 0;
 403                                 return (-2);
 404                         }
 405                         else
 406                         {
 407                                 p->bp = (char*)header;
 408                                 p->cc = endofbuf - (char*)header;
 409                                 return (n);
 410                         }
 411                 }
 412
 413                 if(!dfp)
 414                 {
 415                         /* convert between timestamp formats */
 416                         ts = header->ts;
 417                         pcap_header.ts.tv_sec = (int)(ts >> 32);
 418                         ts = (ts & 0xffffffffi64) * 1000000;
 419                         ts += 0x80000000; /* rounding */
 420                         pcap_header.ts.tv_usec = (int)(ts >> 32);
 421                         if (pcap_header.ts.tv_usec >= 1000000) {
 422                                 pcap_header.ts.tv_usec -= 1000000;
 423                                 pcap_header.ts.tv_sec++;
 424                         }
 425                 }
 426
 427                 /* No underlaying filtering system. We need to filter on our own */
 428                 if (p->fcode.bf_insns)
 429                 {
 430                         if (bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen) == 0)
 431                         {
 432                                 /* Move to next packet */
 433                                 header = (dag_record_t*)((char*)header + erf_record_len);
 434                                 continue;
 435                         }
 436                 }
 437
 438                 /* Fill the header for the user suppplied callback function */
 439                 pcap_header.caplen = caplen;
 440                 pcap_header.len = packet_len;
 441
 442                 /* Call the callback function */
 443                 (*callback)(user, &pcap_header, dp);
 444
 445                 /* Move to next packet */
 446                 header = (dag_record_t*)((char*)header + erf_record_len);
 447
 448                 /* Stop if the number of packets requested by user has been reached*/
 449                 if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt))
 450                 {
 451                         p->bp = (char*)header;
 452                         p->cc = endofbuf - (char*)header;
 453                         return (n);
 454                 }
 455         }
 456         while((u_char*)header < endofbuf);
 457
 458   return 1;
 459 }
 460 #endif /* HAVE_DAG_API */
 461
 462 /* Send a packet to the network */
 463 static int
 464 pcap_inject_win32(pcap_t *p, const void *buf, size_t size){
 465         LPPACKET PacketToSend;
 466
 467         PacketToSend=PacketAllocatePacket();
 468
 469         if (PacketToSend == NULL)
 470         {
 471                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send error: PacketAllocatePacket failed");
 472                 return -1;
 473         }
 474
 475         PacketInitPacket(PacketToSend,(PVOID)buf,size);
 476         if(PacketSendPacket(p->adapter,PacketToSend,TRUE) == FALSE){
 477                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send error: PacketSendPacket failed");
 478                 PacketFreePacket(PacketToSend);
 479                 return -1;
 480         }
 481
 482         PacketFreePacket(PacketToSend);
 483
 484         /*
 485          * We assume it all got sent if "PacketSendPacket()" succeeded.
 486          * "pcap_inject()" is expected to return the number of bytes
 487          * sent.
 488          */
 489         return size;
 490 }
 491
 492 static void
 493 pcap_cleanup_win32(pcap_t *p)
 494 {
 495         if (p->adapter != NULL) {
 496                 PacketCloseAdapter(p->adapter);
 497                 p->adapter = NULL;
 498         }
 499         if (p->Packet) {
 500                 PacketFreePacket(p->Packet);
 501                 p->Packet = NULL;
 502         }
 503         pcap_cleanup_live_common(p);
 504 }
 505
 506 static int
 507 pcap_activate_win32(pcap_t *p)
 508 {
 509         struct pcap_win *pw = p->priv;
 510         NetType type;
 511
 512         if (p->opt.rfmon) {
 513                 /*
 514                  * No monitor mode on Windows.  It could be done on
 515                  * Vista with drivers that support the native 802.11
 516                  * mechanism and monitor mode.
 517                  */
 518                 return (PCAP_ERROR_RFMON_NOTSUP);
 519         }
 520
 521         /* Init WinSock */
 522         wsockinit();
 523
 524         p->adapter = PacketOpenAdapter(p->opt.source);
 525
 526         if (p->adapter == NULL)
 527         {
 528                 /* Adapter detected but we are not able to open it. Return failure. */
 529                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Error opening adapter: %s", pcap_win32strerror());
 530                 return PCAP_ERROR;
 531         }
 532
 533         /*get network type*/
 534         if(PacketGetNetType (p->adapter,&type) == FALSE)
 535         {
 536                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Cannot determine the network type: %s", pcap_win32strerror());
 537                 goto bad;
 538         }
 539
 540         /*Set the linktype*/
 541         switch (type.LinkType)
 542         {
 543         case NdisMediumWan:
 544                 p->linktype = DLT_EN10MB;
 545                 break;
 546
 547         case NdisMedium802_3:
 548                 p->linktype = DLT_EN10MB;
 549                 /*
 550                  * This is (presumably) a real Ethernet capture; give it a
 551                  * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
 552                  * that an application can let you choose it, in case you're
 553                  * capturing DOCSIS traffic that a Cisco Cable Modem
 554                  * Termination System is putting out onto an Ethernet (it
 555                  * doesn't put an Ethernet header onto the wire, it puts raw
 556                  * DOCSIS frames out on the wire inside the low-level
 557                  * Ethernet framing).
 558                  */
 559                 p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
 560                 /*
 561                  * If that fails, just leave the list empty.
 562                  */
 563                 if (p->dlt_list != NULL) {
 564                         p->dlt_list[0] = DLT_EN10MB;
 565                         p->dlt_list[1] = DLT_DOCSIS;
 566                         p->dlt_count = 2;
 567                 }
 568                 break;
 569
 570         case NdisMediumFddi:
 571                 p->linktype = DLT_FDDI;
 572                 break;
 573
 574         case NdisMedium802_5:
 575                 p->linktype = DLT_IEEE802;
 576                 break;
 577
 578         case NdisMediumArcnetRaw:
 579                 p->linktype = DLT_ARCNET;
 580                 break;
 581
 582         case NdisMediumArcnet878_2:
 583                 p->linktype = DLT_ARCNET;
 584                 break;
 585
 586         case NdisMediumAtm:
 587                 p->linktype = DLT_ATM_RFC1483;
 588                 break;
 589
 590         case NdisMediumCHDLC:
 591                 p->linktype = DLT_CHDLC;
 592                 break;
 593
 594         case NdisMediumPPPSerial:
 595                 p->linktype = DLT_PPP_SERIAL;
 596                 break;
 597
 598         case NdisMediumNull:
 599                 p->linktype = DLT_NULL;
 600                 break;
 601
 602         case NdisMediumBare80211:
 603                 p->linktype = DLT_IEEE802_11;
 604                 break;
 605
 606         case NdisMediumRadio80211:
 607                 p->linktype = DLT_IEEE802_11_RADIO;
 608                 break;
 609
 610         case NdisMediumPpi:
 611                 p->linktype = DLT_PPI;
 612                 break;
 613
 614         default:
 615                 p->linktype = DLT_EN10MB;                       /*an unknown adapter is assumed to be ethernet*/
 616                 break;
 617         }
 618
 619         /* Set promiscuous mode */
 620         if (p->opt.promisc)
 621         {
 622
 623                 if (PacketSetHwFilter(p->adapter,NDIS_PACKET_TYPE_PROMISCUOUS) == FALSE)
 624                 {
 625                         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "failed to set hardware filter to promiscuous mode");
 626                         goto bad;
 627                 }
 628         }
 629         else
 630         {
 631                 if (PacketSetHwFilter(p->adapter,NDIS_PACKET_TYPE_ALL_LOCAL) == FALSE)
 632                 {
 633                         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "failed to set hardware filter to non-promiscuous mode");
 634                         goto bad;
 635                 }
 636         }
 637
 638         /* Set the buffer size */
 639         p->bufsize = WIN32_DEFAULT_USER_BUFFER_SIZE;
 640
 641         /* allocate Packet structure used during the capture */
 642         if((p->Packet = PacketAllocatePacket())==NULL)
 643         {
 644                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "failed to allocate the PACKET structure");
 645                 goto bad;
 646         }
 647
 648         if(!(p->adapter->Flags & INFO_FLAG_DAG_CARD))
 649         {
 650         /*
 651          * Traditional Adapter
 652          */
 653                 /*
 654                  * If the buffer size wasn't explicitly set, default to
 655                  * WIN32_DEFAULT_USER_BUFFER_SIZE.
 656                  */
 657                 if (p->opt.buffer_size == 0)
 658                         p->opt.buffer_size = WIN32_DEFAULT_KERNEL_BUFFER_SIZE;
 659
 660                 if(PacketSetBuff(p->adapter,p->opt.buffer_size)==FALSE)
 661                 {
 662                         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "driver error: not enough memory to allocate the kernel buffer");
 663                         goto bad;
 664                 }
 665
 666                 p->buffer = (u_char *)malloc(p->bufsize);
 667                 if (p->buffer == NULL)
 668                 {
 669                         snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", pcap_strerror(errno));
 670                         goto bad;
 671                 }
 672
 673                 PacketInitPacket(p->Packet,(BYTE*)p->buffer,p->bufsize);
 674
 675                 if (p->opt.immediate)
 676                 {
 677                         /* tell the driver to copy the buffer as soon as data arrives */
 678                         if(PacketSetMinToCopy(p->adapter,0)==FALSE)
 679                         {
 680                                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,"Error calling PacketSetMinToCopy: %s", pcap_win32strerror());
 681                                 goto bad;
 682                         }
 683                 }
 684                 else
 685                 {
 686                         /* tell the driver to copy the buffer only if it contains at least 16K */
 687                         if(PacketSetMinToCopy(p->adapter,16000)==FALSE)
 688                         {
 689                                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,"Error calling PacketSetMinToCopy: %s", pcap_win32strerror());
 690                                 goto bad;
 691                         }
 692                 }
 693         }
 694         else
 695 #ifdef HAVE_DAG_API
 696         {
 697         /*
 698          * Dag Card
 699          */
 700                 LONG    status;
 701                 HKEY    dagkey;
 702                 DWORD   lptype;
 703                 DWORD   lpcbdata;
 704                 int             postype = 0;
 705                 char    keyname[512];
 706
 707                 snprintf(keyname, sizeof(keyname), "%s\\CardParams\\%s",
 708                         "SYSTEM\\CurrentControlSet\\Services\\DAG",
 709                         strstr(_strlwr(p->opt.source), "dag"));
 710                 do
 711                 {
 712                         status = RegOpenKeyEx(HKEY_LOCAL_MACHINE, keyname, 0, KEY_READ, &dagkey);
 713                         if(status != ERROR_SUCCESS)
 714                                 break;
 715
 716                         status = RegQueryValueEx(dagkey,
 717                                 "PosType",
 718                                 NULL,
 719                                 &lptype,
 720                                 (char*)&postype,
 721                                 &lpcbdata);
 722
 723                         if(status != ERROR_SUCCESS)
 724                         {
 725                                 postype = 0;
 726                         }
 727
 728                         RegCloseKey(dagkey);
 729                 }
 730                 while(FALSE);
 731
 732
 733                 p->snapshot = PacketSetSnapLen(p->adapter, snaplen);
 734
 735                 /* Set the length of the FCS associated to any packet. This value
 736                  * will be subtracted to the packet length */
 737                 pw->dag_fcs_bits = p->adapter->DagFcsLen;
 738         }
 739 #else
 740         goto bad;
 741 #endif /* HAVE_DAG_API */
 742
 743         PacketSetReadTimeout(p->adapter, p->opt.timeout);
 744
 745 #ifdef HAVE_DAG_API
 746         if(p->adapter->Flags & INFO_FLAG_DAG_CARD)
 747         {
 748                 /* install dag specific handlers for read and setfilter */
 749                 p->read_op = pcap_read_win32_dag;
 750                 p->setfilter_op = pcap_setfilter_win32_dag;
 751         }
 752         else
 753         {
 754 #endif /* HAVE_DAG_API */
 755                 /* install traditional npf handlers for read and setfilter */
 756                 p->read_op = pcap_read_win32_npf;
 757                 p->setfilter_op = pcap_setfilter_win32_npf;
 758 #ifdef HAVE_DAG_API
 759         }
 760 #endif /* HAVE_DAG_API */
 761         p->setdirection_op = NULL;      /* Not implemented. */
 762             /* XXX - can this be implemented on some versions of Windows? */
 763         p->inject_op = pcap_inject_win32;
 764         p->set_datalink_op = NULL;      /* can't change data link type */
 765         p->getnonblock_op = pcap_getnonblock_win32;
 766         p->setnonblock_op = pcap_setnonblock_win32;
 767         p->stats_op = pcap_stats_win32;
 768         p->setbuff_op = pcap_setbuff_win32;
 769         p->setmode_op = pcap_setmode_win32;
 770         p->setmintocopy_op = pcap_setmintocopy_win32;
 771         p->getadapter_op = pcap_getadapter_win32;
 772         p->cleanup_op = pcap_cleanup_win32;
 773
 774         return (0);
 775 bad:
 776         pcap_cleanup_win32(p);
 777         return (PCAP_ERROR);
 778 }
 779
 780 pcap_t *
 781 pcap_create_interface(const char *device, char *ebuf)
 782 {
 783         pcap_t *p;
 784
 785         if (strlen(device) == 1)
 786         {
 787                 /*
 788                  * It's probably a unicode string
 789                  * Convert to ascii and pass it to pcap_create_common
 790                  *
 791                  * This wonderful hack is needed because pcap_lookupdev still returns
 792                  * unicode strings, and it's used by windump when no device is specified
 793                  * in the command line
 794                  */
 795                 size_t length;
 796                 char* deviceAscii;
 797
 798                 length = wcslen((wchar_t*)device);
 799
 800                 deviceAscii = (char*)malloc(length + 1);
 801
 802                 if (deviceAscii == NULL)
 803                 {
 804                         snprintf(ebuf, PCAP_ERRBUF_SIZE, "Malloc failed");
 805                         return NULL;
 806                 }
 807
 808                 snprintf(deviceAscii, length + 1, "%ws", (wchar_t*)device);
 809                 p = pcap_create_common(deviceAscii, ebuf, sizeof (struct pcap_win));
 810                 free(deviceAscii);
 811         }
 812         else
 813         {
 814                 p = pcap_create_common(device, ebuf, sizeof (struct pcap_win));
 815         }
 816
 817         if (p == NULL)
 818                 return (NULL);
 819
 820         p->activate_op = pcap_activate_win32;
 821         return (p);
 822 }
 823
 824 static int
 825 pcap_setfilter_win32_npf(pcap_t *p, struct bpf_program *fp)
 826 {
 827         struct pcap_win *pw = p->priv;
 828
 829         if(PacketSetBpf(p->adapter,fp)==FALSE){
 830                 /*
 831                  * Kernel filter not installed.
 832                  *
 833                  * XXX - we don't know whether this failed because:
 834                  *
 835                  *  the kernel rejected the filter program as invalid,
 836                  *  in which case we should fall back on userland
 837                  *  filtering;
 838                  *
 839                  *  the kernel rejected the filter program as too big,
 840                  *  in which case we should again fall back on
 841                  *  userland filtering;
 842                  *
 843                  *  there was some other problem, in which case we
 844                  *  should probably report an error.
 845                  *
 846                  * For NPF devices, the Win32 status will be
 847                  * STATUS_INVALID_DEVICE_REQUEST for invalid
 848                  * filters, but I don't know what it'd be for
 849                  * other problems, and for some other devices
 850                  * it might not be set at all.
 851                  *
 852                  * So we just fall back on userland filtering in
 853                  * all cases.
 854                  */
 855
 856                 /*
 857                  * install_bpf_program() validates the program.
 858                  *
 859                  * XXX - what if we already have a filter in the kernel?
 860                  */
 861                 if (install_bpf_program(p, fp) < 0)
 862                         return (-1);
 863                 pw->filtering_in_kernel = 0;    /* filtering in userland */
 864                 return (0);
 865         }
 866
 867         /*
 868          * It worked.
 869          */
 870         pw->filtering_in_kernel = 1;    /* filtering in the kernel */
 871
 872         /*
 873          * Discard any previously-received packets, as they might have
 874          * passed whatever filter was formerly in effect, but might
 875          * not pass this filter (BIOCSETF discards packets buffered
 876          * in the kernel, so you can lose packets in any case).
 877          */
 878         p->cc = 0;
 879         return (0);
 880 }
 881
 882 /*
 883  * We filter at user level, since the kernel driver does't process the packets
 884  */
 885 static int
 886 pcap_setfilter_win32_dag(pcap_t *p, struct bpf_program *fp) {
 887
 888         if(!fp)
 889         {
 890                 strncpy(p->errbuf, "setfilter: No filter specified", sizeof(p->errbuf));
 891                 return -1;
 892         }
 893
 894         /* Install a user level filter */
 895         if (install_bpf_program(p, fp) < 0)
 896         {
 897                 snprintf(p->errbuf, sizeof(p->errbuf),
 898                         "setfilter, unable to install the filter: %s", pcap_strerror(errno));
 899                 return -1;
 900         }
 901
 902         return (0);
 903 }
 904
 905 static int
 906 pcap_getnonblock_win32(pcap_t *p, char *errbuf)
 907 {
 908         struct pcap_win *pw = p->priv;
 909
 910         /*
 911          * XXX - if there were a PacketGetReadTimeout() call, we
 912          * would use it, and return 1 if the timeout is -1
 913          * and 0 otherwise.
 914          */
 915         return (pw->nonblock);
 916 }
 917
 918 static int
 919 pcap_setnonblock_win32(pcap_t *p, int nonblock, char *errbuf)
 920 {
 921         struct pcap_win *pw = p->priv;
 922         int newtimeout;
 923
 924         if (nonblock) {
 925                 /*
 926                  * Set the read timeout to -1 for non-blocking mode.
 927                  */
 928                 newtimeout = -1;
 929         } else {
 930                 /*
 931                  * Restore the timeout set when the device was opened.
 932                  * (Note that this may be -1, in which case we're not
 933                  * really leaving non-blocking mode.)
 934                  */
 935                 newtimeout = p->opt.timeout;
 936         }
 937         if (!PacketSetReadTimeout(p->adapter, newtimeout)) {
 938                 snprintf(errbuf, PCAP_ERRBUF_SIZE,
 939                     "PacketSetReadTimeout: %s", pcap_win32strerror());
 940                 return (-1);
 941         }
 942         pw->nonblock = (newtimeout == -1);
 943         return (0);
 944 }
 945
 946 /*platform-dependent routine to add devices other than NDIS interfaces*/
 947 int
 948 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 949 {
 950         return (0);
 951 }