contrib/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 1.31.2.8 2008-04-14 20:41:51 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 #define ATM_CELL_SIZE           52
  52 #define ATM_HDR_SIZE            4
  53
  54 /*
  55  * A header containing additional MTP information.
  56  */
  57 #define MTP2_SENT_OFFSET                0       /* 1 byte */
  58 #define MTP2_ANNEX_A_USED_OFFSET        1       /* 1 byte */
  59 #define MTP2_LINK_NUMBER_OFFSET         2       /* 2 bytes */
  60 #define MTP2_HDR_LEN                    4       /* length of the header */
  61
  62 #define MTP2_ANNEX_A_NOT_USED      0
  63 #define MTP2_ANNEX_A_USED          1
  64 #define MTP2_ANNEX_A_USED_UNKNOWN  2
  65
  66 /* SunATM pseudo header */
  67 struct sunatm_hdr {
  68         unsigned char   flags;          /* destination and traffic type */
  69         unsigned char   vpi;            /* VPI */
  70         unsigned short  vci;            /* VCI */
  71 };
  72
  73 typedef struct pcap_dag_node {
  74         struct pcap_dag_node *next;
  75         pcap_t *p;
  76         pid_t pid;
  77 } pcap_dag_node_t;
  78
  79 static pcap_dag_node_t *pcap_dags = NULL;
  80 static int atexit_handler_installed = 0;
  81 static const unsigned short endian_test_word = 0x0100;
  82
  83 #define IS_BIGENDIAN() (*((unsigned char *)&endian_test_word))
  84
  85
  86 #ifdef DAG_ONLY
  87 /* This code is required when compiling for a DAG device only. */
  88
  89 /* Replace dag function names with pcap equivalent. */
  90 #define dag_create pcap_create
  91 #define dag_platform_finddevs pcap_platform_finddevs
  92 #endif /* DAG_ONLY */
  93
  94 #define MAX_DAG_PACKET 65536
  95
  96 static unsigned char TempPkt[MAX_DAG_PACKET];
  97
  98 static int dag_setfilter(pcap_t *p, struct bpf_program *fp);
  99 static int dag_stats(pcap_t *p, struct pcap_stat *ps);
 100 static int dag_set_datalink(pcap_t *p, int dlt);
 101 static int dag_get_datalink(pcap_t *p);
 102 static int dag_setnonblock(pcap_t *p, int nonblock, char *errbuf);
 103
 104 static void
 105 delete_pcap_dag(pcap_t *p)
 106 {
 107         pcap_dag_node_t *curr = NULL, *prev = NULL;
 108
 109         for (prev = NULL, curr = pcap_dags; curr != NULL && curr->p != p; prev = curr, curr = curr->next) {
 110                 /* empty */
 111         }
 112
 113         if (curr != NULL && curr->p == p) {
 114                 if (prev != NULL) {
 115                         prev->next = curr->next;
 116                 } else {
 117                         pcap_dags = curr->next;
 118                 }
 119         }
 120 }
 121
 122 /*
 123  * Performs a graceful shutdown of the DAG card, frees dynamic memory held
 124  * in the pcap_t structure, and closes the file descriptor for the DAG card.
 125  */
 126
 127 static void
 128 dag_platform_cleanup(pcap_t *p)
 129 {
 130
 131         if (p != NULL) {
 132 #ifdef HAVE_DAG_STREAMS_API
 133                 if(dag_stop_stream(p->fd, p->md.dag_stream) < 0)
 134                         fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
 135
 136                 if(dag_detach_stream(p->fd, p->md.dag_stream) < 0)
 137                         fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
 138 #else
 139                 if(dag_stop(p->fd) < 0)
 140                         fprintf(stderr,"dag_stop: %s\n", strerror(errno));
 141 #endif /* HAVE_DAG_STREAMS_API */
 142                 if(p->fd != -1) {
 143                         if(dag_close(p->fd) < 0)
 144                                 fprintf(stderr,"dag_close: %s\n", strerror(errno));
 145                         p->fd = -1;
 146                 }
 147                 delete_pcap_dag(p);
 148                 pcap_cleanup_live_common(p);
 149         }
 150         /* Note: don't need to call close(p->fd) here as dag_close(p->fd) does this. */
 151 }
 152
 153 static void
 154 atexit_handler(void)
 155 {
 156         while (pcap_dags != NULL) {
 157                 if (pcap_dags->pid == getpid()) {
 158                         dag_platform_cleanup(pcap_dags->p);
 159                 } else {
 160                         delete_pcap_dag(pcap_dags->p);
 161                 }
 162         }
 163 }
 164
 165 static int
 166 new_pcap_dag(pcap_t *p)
 167 {
 168         pcap_dag_node_t *node = NULL;
 169
 170         if ((node = malloc(sizeof(pcap_dag_node_t))) == NULL) {
 171                 return -1;
 172         }
 173
 174         if (!atexit_handler_installed) {
 175                 atexit(atexit_handler);
 176                 atexit_handler_installed = 1;
 177         }
 178
 179         node->next = pcap_dags;
 180         node->p = p;
 181         node->pid = getpid();
 182
 183         pcap_dags = node;
 184
 185         return 0;
 186 }
 187
 188 static unsigned int
 189 dag_erf_ext_header_count(uint8_t * erf, size_t len)
 190 {
 191         uint32_t hdr_num = 0;
 192         uint8_t  hdr_type;
 193
 194         /* basic sanity checks */
 195         if ( erf == NULL )
 196                 return 0;
 197         if ( len < 16 )
 198                 return 0;
 199
 200         /* check if we have any extension headers */
 201         if ( (erf[8] & 0x80) == 0x00 )
 202                 return 0;
 203
 204         /* loop over the extension headers */
 205         do {
 206
 207                 /* sanity check we have enough bytes */
 208                 if ( len <= (24 + (hdr_num * 8)) )
 209                         return hdr_num;
 210
 211                 /* get the header type */
 212                 hdr_type = erf[(16 + (hdr_num * 8))];
 213                 hdr_num++;
 214
 215         } while ( hdr_type & 0x80 );
 216
 217         return hdr_num;
 218 }
 219
 220 /*
 221  *  Read at most max_packets from the capture stream and call the callback
 222  *  for each of them. Returns the number of packets handled, -1 if an
 223  *  error occured, or -2 if we were told to break out of the loop.
 224  */
 225 static int
 226 dag_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
 227 {
 228         unsigned int processed = 0;
 229         int flags = p->md.dag_offset_flags;
 230         unsigned int nonblocking = flags & DAGF_NONBLOCK;
 231         unsigned int num_ext_hdr = 0;
 232
 233         /* Get the next bufferful of packets (if necessary). */
 234         while (p->md.dag_mem_top - p->md.dag_mem_bottom < dag_record_size) {
 235
 236                 /*
 237                  * Has "pcap_breakloop()" been called?
 238                  */
 239                 if (p->break_loop) {
 240                         /*
 241                          * Yes - clear the flag that indicates that
 242                          * it has, and return -2 to indicate that
 243                          * we were told to break out of the loop.
 244                          */
 245                         p->break_loop = 0;
 246                         return -2;
 247                 }
 248
 249 #ifdef HAVE_DAG_STREAMS_API
 250                 /* dag_advance_stream() will block (unless nonblock is called)
 251                  * until 64kB of data has accumulated.
 252                  * If to_ms is set, it will timeout before 64kB has accumulated.
 253                  * We wait for 64kB because processing a few packets at a time
 254                  * can cause problems at high packet rates (>200kpps) due
 255                  * to inefficiencies.
 256                  * This does mean if to_ms is not specified the capture may 'hang'
 257                  * for long periods if the data rate is extremely slow (<64kB/sec)
 258                  * If non-block is specified it will return immediately. The user
 259                  * is then responsible for efficiency.
 260                  */
 261                 if ( NULL == (p->md.dag_mem_top = dag_advance_stream(p->fd, p->md.dag_stream, &(p->md.dag_mem_bottom))) ) {
 262                      return -1;
 263                 }
 264 #else
 265                 /* dag_offset does not support timeouts */
 266                 p->md.dag_mem_top = dag_offset(p->fd, &(p->md.dag_mem_bottom), flags);
 267 #endif /* HAVE_DAG_STREAMS_API */
 268
 269                 if (nonblocking && (p->md.dag_mem_top - p->md.dag_mem_bottom < dag_record_size))
 270                 {
 271                         /* Pcap is configured to process only available packets, and there aren't any, return immediately. */
 272                         return 0;
 273                 }
 274
 275                 if(!nonblocking &&
 276                    p->md.dag_timeout &&
 277                    (p->md.dag_mem_top - p->md.dag_mem_bottom < dag_record_size))
 278                 {
 279                         /* Blocking mode, but timeout set and no data has arrived, return anyway.*/
 280                         return 0;
 281                 }
 282
 283         }
 284
 285         /* Process the packets. */
 286         while (p->md.dag_mem_top - p->md.dag_mem_bottom >= dag_record_size) {
 287
 288                 unsigned short packet_len = 0;
 289                 int caplen = 0;
 290                 struct pcap_pkthdr      pcap_header;
 291
 292 #ifdef HAVE_DAG_STREAMS_API
 293                 dag_record_t *header = (dag_record_t *)(p->md.dag_mem_bottom);
 294 #else
 295                 dag_record_t *header = (dag_record_t *)(p->md.dag_mem_base + p->md.dag_mem_bottom);
 296 #endif /* HAVE_DAG_STREAMS_API */
 297
 298                 u_char *dp = ((u_char *)header); /* + dag_record_size; */
 299                 unsigned short rlen;
 300
 301                 /*
 302                  * Has "pcap_breakloop()" been called?
 303                  */
 304                 if (p->break_loop) {
 305                         /*
 306                          * Yes - clear the flag that indicates that
 307                          * it has, and return -2 to indicate that
 308                          * we were told to break out of the loop.
 309                          */
 310                         p->break_loop = 0;
 311                         return -2;
 312                 }
 313
 314                 rlen = ntohs(header->rlen);
 315                 if (rlen < dag_record_size)
 316                 {
 317                         strncpy(p->errbuf, "dag_read: record too small", PCAP_ERRBUF_SIZE);
 318                         return -1;
 319                 }
 320                 p->md.dag_mem_bottom += rlen;
 321
 322                 /* Count lost packets. */
 323                 switch((header->type & 0x7f)) {
 324                         /* in these types the color value overwrites the lctr */
 325                 case TYPE_COLOR_HDLC_POS:
 326                 case TYPE_COLOR_ETH:
 327                 case TYPE_DSM_COLOR_HDLC_POS:
 328                 case TYPE_DSM_COLOR_ETH:
 329                 case TYPE_COLOR_MC_HDLC_POS:
 330                 case TYPE_COLOR_HASH_ETH:
 331                 case TYPE_COLOR_HASH_POS:
 332                         break;
 333
 334                 default:
 335                         if (header->lctr) {
 336                                 if (p->md.stat.ps_drop > (UINT_MAX - ntohs(header->lctr))) {
 337                                         p->md.stat.ps_drop = UINT_MAX;
 338                                 } else {
 339                                         p->md.stat.ps_drop += ntohs(header->lctr);
 340                                 }
 341                         }
 342                 }
 343
 344                 if ((header->type & 0x7f) == TYPE_PAD) {
 345                         continue;
 346                 }
 347
 348                 num_ext_hdr = dag_erf_ext_header_count(dp, rlen);
 349
 350                 /* ERF encapsulation */
 351                 /* The Extensible Record Format is not dropped for this kind of encapsulation,
 352                  * and will be handled as a pseudo header by the decoding application.
 353                  * The information carried in the ERF header and in the optional subheader (if present)
 354                  * could be merged with the libpcap information, to offer a better decoding.
 355                  * The packet length is
 356                  * o the length of the packet on the link (header->wlen),
 357                  * o plus the length of the ERF header (dag_record_size), as the length of the
 358                  *   pseudo header will be adjusted during the decoding,
 359                  * o plus the length of the optional subheader (if present).
 360                  *
 361                  * The capture length is header.rlen and the byte stuffing for alignment will be dropped
 362                  * if the capture length is greater than the packet length.
 363                  */
 364                 if (p->linktype == DLT_ERF) {
 365                         packet_len = ntohs(header->wlen) + dag_record_size;
 366                         caplen = rlen;
 367                         switch ((header->type & 0x7f)) {
 368                         case TYPE_MC_AAL5:
 369                         case TYPE_MC_ATM:
 370                         case TYPE_MC_HDLC:
 371                                 packet_len += 4; /* MC header */
 372                                 break;
 373
 374                         case TYPE_COLOR_HASH_ETH:
 375                         case TYPE_DSM_COLOR_ETH:
 376                         case TYPE_COLOR_ETH:
 377                         case TYPE_ETH:
 378                                 packet_len += 2; /* ETH header */
 379                                 break;
 380                         } /* switch type */
 381
 382                         /* Include ERF extension headers */
 383                         packet_len += (8 * num_ext_hdr);
 384
 385                         if (caplen > packet_len) {
 386                                 caplen = packet_len;
 387                         }
 388                 } else {
 389                         /* Other kind of encapsulation according to the header Type */
 390
 391                         /* Skip over generic ERF header */
 392                         dp += dag_record_size;
 393                         /* Skip over extension headers */
 394                         dp += 8 * num_ext_hdr;
 395
 396                         switch((header->type & 0x7f)) {
 397                         case TYPE_ATM:
 398                         case TYPE_AAL5:
 399                                 if (header->type == TYPE_AAL5) {
 400                                         packet_len = ntohs(header->wlen);
 401                                         caplen = rlen - dag_record_size;
 402                                 }
 403                         case TYPE_MC_ATM:
 404                                 if (header->type == TYPE_MC_ATM) {
 405                                         caplen = packet_len = ATM_CELL_SIZE;
 406                                         dp+=4;
 407                                 }
 408                         case TYPE_MC_AAL5:
 409                                 if (header->type == TYPE_MC_AAL5) {
 410                                         packet_len = ntohs(header->wlen);
 411                                         caplen = rlen - dag_record_size - 4;
 412                                         dp+=4;
 413                                 }
 414                                 if (header->type == TYPE_ATM) {
 415                                         caplen = packet_len = ATM_CELL_SIZE;
 416                                 }
 417                                 if (p->linktype == DLT_SUNATM) {
 418                                         struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
 419                                         unsigned long rawatm;
 420
 421                                         rawatm = ntohl(*((unsigned long *)dp));
 422                                         sunatm->vci = htons((rawatm >>  4) & 0xffff);
 423                                         sunatm->vpi = (rawatm >> 20) & 0x00ff;
 424                                         sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) |
 425                                                 ((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
 426                                                  ((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 :
 427                                                   ((dp[ATM_HDR_SIZE] == 0xaa &&
 428                                                     dp[ATM_HDR_SIZE+1] == 0xaa &&
 429                                                     dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
 430
 431                                 } else {
 432                                         packet_len -= ATM_HDR_SIZE;
 433                                         caplen -= ATM_HDR_SIZE;
 434                                         dp += ATM_HDR_SIZE;
 435                                 }
 436                                 break;
 437
 438                         case TYPE_COLOR_HASH_ETH:
 439                         case TYPE_DSM_COLOR_ETH:
 440                         case TYPE_COLOR_ETH:
 441                         case TYPE_ETH:
 442                                 packet_len = ntohs(header->wlen);
 443                                 packet_len -= (p->md.dag_fcs_bits >> 3);
 444                                 caplen = rlen - dag_record_size - 2;
 445                                 if (caplen > packet_len) {
 446                                         caplen = packet_len;
 447                                 }
 448                                 dp += 2;
 449                                 break;
 450
 451                         case TYPE_COLOR_HASH_POS:
 452                         case TYPE_DSM_COLOR_HDLC_POS:
 453                         case TYPE_COLOR_HDLC_POS:
 454                         case TYPE_HDLC_POS:
 455                                 packet_len = ntohs(header->wlen);
 456                                 packet_len -= (p->md.dag_fcs_bits >> 3);
 457                                 caplen = rlen - dag_record_size;
 458                                 if (caplen > packet_len) {
 459                                         caplen = packet_len;
 460                                 }
 461                                 break;
 462
 463                         case TYPE_COLOR_MC_HDLC_POS:
 464                         case TYPE_MC_HDLC:
 465                                 packet_len = ntohs(header->wlen);
 466                                 packet_len -= (p->md.dag_fcs_bits >> 3);
 467                                 caplen = rlen - dag_record_size - 4;
 468                                 if (caplen > packet_len) {
 469                                         caplen = packet_len;
 470                                 }
 471                                 /* jump the MC_HDLC_HEADER */
 472                                 dp += 4;
 473 #ifdef DLT_MTP2_WITH_PHDR
 474                                 if (p->linktype == DLT_MTP2_WITH_PHDR) {
 475                                         /* Add the MTP2 Pseudo Header */
 476                                         caplen += MTP2_HDR_LEN;
 477                                         packet_len += MTP2_HDR_LEN;
 478
 479                                         TempPkt[MTP2_SENT_OFFSET] = 0;
 480                                         TempPkt[MTP2_ANNEX_A_USED_OFFSET] = MTP2_ANNEX_A_USED_UNKNOWN;
 481                                         *(TempPkt+MTP2_LINK_NUMBER_OFFSET) = ((header->rec.mc_hdlc.mc_header>>16)&0x01);
 482                                         *(TempPkt+MTP2_LINK_NUMBER_OFFSET+1) = ((header->rec.mc_hdlc.mc_header>>24)&0xff);
 483                                         memcpy(TempPkt+MTP2_HDR_LEN, dp, caplen);
 484                                         dp = TempPkt;
 485                                 }
 486 #endif
 487                                 break;
 488
 489                         case TYPE_IPV4:
 490                                 packet_len = ntohs(header->wlen);
 491                                 caplen = rlen - dag_record_size;
 492                                 if (caplen > packet_len) {
 493                                         caplen = packet_len;
 494                                 }
 495                                 break;
 496
 497                         default:
 498                                 /* Unhandled ERF type.
 499                                  * Ignore rather than generating error
 500                                  */
 501                                 continue;
 502                         } /* switch type */
 503
 504                         /* Skip over extension headers */
 505                         caplen -= (8 * num_ext_hdr);
 506
 507                 } /* ERF encapsulation */
 508
 509                 if (caplen > p->snapshot)
 510                         caplen = p->snapshot;
 511
 512                 /* Run the packet filter if there is one. */
 513                 if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
 514
 515                         /* convert between timestamp formats */
 516                         register unsigned long long ts;
 517
 518                         if (IS_BIGENDIAN()) {
 519                                 ts = SWAPLL(header->ts);
 520                         } else {
 521                                 ts = header->ts;
 522                         }
 523
 524                         pcap_header.ts.tv_sec = ts >> 32;
 525                         ts = (ts & 0xffffffffULL) * 1000000;
 526                         ts += 0x80000000; /* rounding */
 527                         pcap_header.ts.tv_usec = ts >> 32;
 528                         if (pcap_header.ts.tv_usec >= 1000000) {
 529                                 pcap_header.ts.tv_usec -= 1000000;
 530                                 pcap_header.ts.tv_sec++;
 531                         }
 532
 533                         /* Fill in our own header data */
 534                         pcap_header.caplen = caplen;
 535                         pcap_header.len = packet_len;
 536
 537                         /* Count the packet. */
 538                         p->md.stat.ps_recv++;
 539
 540                         /* Call the user supplied callback function */
 541                         callback(user, &pcap_header, dp);
 542
 543                         /* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
 544                         processed++;
 545                         if (processed == cnt && cnt > 0)
 546                         {
 547                                 /* Reached the user-specified limit. */
 548                                 return cnt;
 549                         }
 550                 }
 551         }
 552
 553         return processed;
 554 }
 555
 556 static int
 557 dag_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
 558 {
 559         strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
 560             PCAP_ERRBUF_SIZE);
 561         return (-1);
 562 }
 563
 564 /*
 565  *  Get a handle for a live capture from the given DAG device.  Passing a NULL
 566  *  device will result in a failure.  The promisc flag is ignored because DAG
 567  *  cards are always promiscuous.  The to_ms parameter is used in setting the
 568  *  API polling parameters.
 569  *
 570  *  snaplen is now also ignored, until we get per-stream slen support. Set
 571  *  slen with approprite DAG tool BEFORE pcap_activate().
 572  *
 573  *  See also pcap(3).
 574  */
 575 static int dag_activate(pcap_t* handle)
 576 {
 577 #if 0
 578         char conf[30]; /* dag configure string */
 579 #endif
 580         char *s;
 581         int n;
 582         daginf_t* daginf;
 583         char * newDev = NULL;
 584         char * device = handle->opt.source;
 585 #ifdef HAVE_DAG_STREAMS_API
 586         uint32_t mindata;
 587         struct timeval maxwait;
 588         struct timeval poll;
 589 #endif
 590
 591         if (device == NULL) {
 592                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "device is NULL: %s", pcap_strerror(errno));
 593                 return -1;
 594         }
 595
 596         /* Initialize some components of the pcap structure. */
 597
 598 #ifdef HAVE_DAG_STREAMS_API
 599         newDev = (char *)malloc(strlen(device) + 16);
 600         if (newDev == NULL) {
 601                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
 602                 goto fail;
 603         }
 604
 605         /* Parse input name to get dag device and stream number if provided */
 606         if (dag_parse_name(device, newDev, strlen(device) + 16, &handle->md.dag_stream) < 0) {
 607                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: %s\n", pcap_strerror(errno));
 608                 goto fail;
 609         }
 610         device = newDev;
 611
 612         if (handle->md.dag_stream%2) {
 613                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: tx (even numbered) streams not supported for capture\n");
 614                 goto fail;
 615         }
 616 #else
 617         if (strncmp(device, "/dev/", 5) != 0) {
 618                 newDev = (char *)malloc(strlen(device) + 5);
 619                 if (newDev == NULL) {
 620                         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
 621                         goto fail;
 622                 }
 623                 strcpy(newDev, "/dev/");
 624                 strcat(newDev, device);
 625                 device = newDev;
 626         }
 627 #endif /* HAVE_DAG_STREAMS_API */
 628
 629         /* setup device parameters */
 630         if((handle->fd = dag_open((char *)device)) < 0) {
 631                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_open %s: %s", device, pcap_strerror(errno));
 632                 goto fail;
 633         }
 634
 635 #ifdef HAVE_DAG_STREAMS_API
 636         /* Open requested stream. Can fail if already locked or on error */
 637         if (dag_attach_stream(handle->fd, handle->md.dag_stream, 0, 0) < 0) {
 638                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_attach_stream: %s\n", pcap_strerror(errno));
 639                 goto failclose;
 640         }
 641
 642         /* Set up default poll parameters for stream
 643          * Can be overridden by pcap_set_nonblock()
 644          */
 645         if (dag_get_stream_poll(handle->fd, handle->md.dag_stream,
 646                                 &mindata, &maxwait, &poll) < 0) {
 647                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
 648                 goto faildetach;
 649         }
 650
 651         /* Amount of data to collect in Bytes before calling callbacks.
 652          * Important for efficiency, but can introduce latency
 653          * at low packet rates if to_ms not set!
 654          */
 655         mindata = 65536;
 656
 657         /* Obey md.timeout (was to_ms) if supplied. This is a good idea!
 658          * Recommend 10-100ms. Calls will time out even if no data arrived.
 659          */
 660         maxwait.tv_sec = handle->md.timeout/1000;
 661         maxwait.tv_usec = (handle->md.timeout%1000) * 1000;
 662
 663         if (dag_set_stream_poll(handle->fd, handle->md.dag_stream,
 664                                 mindata, &maxwait, &poll) < 0) {
 665                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
 666                 goto faildetach;
 667         }
 668
 669 #else
 670         if((handle->md.dag_mem_base = dag_mmap(handle->fd)) == MAP_FAILED) {
 671                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_mmap %s: %s\n", device, pcap_strerror(errno));
 672                 goto failclose;
 673         }
 674
 675 #endif /* HAVE_DAG_STREAMS_API */
 676
 677         /* XXX Not calling dag_configure() to set slen; this is unsafe in
 678          * multi-stream environments as the gpp config is global.
 679          * Once the firmware provides 'per-stream slen' this can be supported
 680          * again via the Config API without side-effects */
 681 #if 0
 682         /* set the card snap length to the specified snaplen parameter */
 683         /* This is a really bad idea, as different cards have different
 684          * valid slen ranges. Should fix in Config API. */
 685         if (handle->snapshot == 0 || handle->snapshot > MAX_DAG_SNAPLEN) {
 686                 handle->snapshot = MAX_DAG_SNAPLEN;
 687         } else if (snaplen < MIN_DAG_SNAPLEN) {
 688                 handle->snapshot = MIN_DAG_SNAPLEN;
 689         }
 690         /* snap len has to be a multiple of 4 */
 691         snprintf(conf, 30, "varlen slen=%d", (snaplen + 3) & ~3);
 692
 693         if(dag_configure(handle->fd, conf) < 0) {
 694                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_configure %s: %s\n", device, pcap_strerror(errno));
 695                 goto faildetach;
 696         }
 697 #endif
 698
 699 #ifdef HAVE_DAG_STREAMS_API
 700         if(dag_start_stream(handle->fd, handle->md.dag_stream) < 0) {
 701                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start_stream %s: %s\n", device, pcap_strerror(errno));
 702                 goto faildetach;
 703         }
 704 #else
 705         if(dag_start(handle->fd) < 0) {
 706                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start %s: %s\n", device, pcap_strerror(errno));
 707                 goto failclose;
 708         }
 709 #endif /* HAVE_DAG_STREAMS_API */
 710
 711         /*
 712          * Important! You have to ensure bottom is properly
 713          * initialized to zero on startup, it won't give you
 714          * a compiler warning if you make this mistake!
 715          */
 716         handle->md.dag_mem_bottom = 0;
 717         handle->md.dag_mem_top = 0;
 718
 719         /*
 720          * Find out how many FCS bits we should strip.
 721          * First, query the card to see if it strips the FCS.
 722          */
 723         daginf = dag_info(handle->fd);
 724         if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code)) {
 725                 /* DAG 4.2S and 4.23S already strip the FCS.  Stripping the final word again truncates the packet. */
 726                 handle->md.dag_fcs_bits = 0;
 727
 728                 /* Note that no FCS will be supplied. */
 729                 handle->linktype_ext = LT_FCS_DATALINK_EXT(0);
 730         } else {
 731                 /*
 732                  * Start out assuming it's 32 bits.
 733                  */
 734                 handle->md.dag_fcs_bits = 32;
 735
 736                 /* Allow an environment variable to override. */
 737                 if ((s = getenv("ERF_FCS_BITS")) != NULL) {
 738                         if ((n = atoi(s)) == 0 || n == 16 || n == 32) {
 739                                 handle->md.dag_fcs_bits = n;
 740                         } else {
 741                                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 742                                         "pcap_activate %s: bad ERF_FCS_BITS value (%d) in environment\n", device, n);
 743                                 goto failstop;
 744                         }
 745                 }
 746
 747                 /*
 748                  * Did the user request that they not be stripped?
 749                  */
 750                 if ((s = getenv("ERF_DONT_STRIP_FCS")) != NULL) {
 751                         /* Yes.  Note the number of bytes that will be
 752                            supplied. */
 753                         handle->linktype_ext = LT_FCS_DATALINK_EXT(handle->md.dag_fcs_bits/16);
 754
 755                         /* And don't strip them. */
 756                         handle->md.dag_fcs_bits = 0;
 757                 }
 758         }
 759
 760         handle->md.dag_timeout  = handle->md.timeout;
 761
 762         handle->linktype = -1;
 763         if (dag_get_datalink(handle) < 0)
 764                 goto failstop;
 765
 766         handle->bufsize = 0;
 767
 768         if (new_pcap_dag(handle) < 0) {
 769                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "new_pcap_dag %s: %s\n", device, pcap_strerror(errno));
 770                 goto failstop;
 771         }
 772
 773         /*
 774          * "select()" and "poll()" don't work on DAG device descriptors.
 775          */
 776         handle->selectable_fd = -1;
 777
 778         if (newDev != NULL) {
 779                 free((char *)newDev);
 780         }
 781
 782         handle->read_op = dag_read;
 783         handle->inject_op = dag_inject;
 784         handle->setfilter_op = dag_setfilter;
 785         handle->setdirection_op = NULL; /* Not implemented.*/
 786         handle->set_datalink_op = dag_set_datalink;
 787         handle->getnonblock_op = pcap_getnonblock_fd;
 788         handle->setnonblock_op = dag_setnonblock;
 789         handle->stats_op = dag_stats;
 790         handle->cleanup_op = dag_platform_cleanup;
 791         handle->md.stat.ps_drop = 0;
 792         handle->md.stat.ps_recv = 0;
 793         return 0;
 794
 795 #ifdef HAVE_DAG_STREAMS_API
 796 failstop:
 797         if (dag_stop_stream(handle->fd, handle->md.dag_stream) < 0) {
 798                 fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
 799         }
 800
 801 faildetach:
 802         if (dag_detach_stream(handle->fd, handle->md.dag_stream) < 0)
 803                 fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
 804 #else
 805 failstop:
 806         if (dag_stop(handle->fd) < 0)
 807                 fprintf(stderr,"dag_stop: %s\n", strerror(errno));
 808 #endif /* HAVE_DAG_STREAMS_API */
 809
 810 failclose:
 811         if (dag_close(handle->fd) < 0)
 812                 fprintf(stderr,"dag_close: %s\n", strerror(errno));
 813         delete_pcap_dag(handle);
 814
 815 fail:
 816         pcap_cleanup_live_common(handle);
 817         if (newDev != NULL) {
 818                 free((char *)newDev);
 819         }
 820
 821         return PCAP_ERROR;
 822 }
 823
 824 pcap_t *dag_create(const char *device, char *ebuf)
 825 {
 826         pcap_t *p;
 827
 828         p = pcap_create_common(device, ebuf);
 829         if (p == NULL)
 830                 return NULL;
 831
 832         p->activate_op = dag_activate;
 833         return p;
 834 }
 835
 836 static int
 837 dag_stats(pcap_t *p, struct pcap_stat *ps) {
 838         /* This needs to be filled out correctly.  Hopefully a dagapi call will
 839                  provide all necessary information.
 840         */
 841         /*p->md.stat.ps_recv = 0;*/
 842         /*p->md.stat.ps_drop = 0;*/
 843
 844         *ps = p->md.stat;
 845
 846         return 0;
 847 }
 848
 849 /*
 850  * Previously we just generated a list of all possible names and let
 851  * pcap_add_if() attempt to open each one, but with streams this adds up
 852  * to 81 possibilities which is inefficient.
 853  *
 854  * Since we know more about the devices we can prune the tree here.
 855  * pcap_add_if() will still retest each device but the total number of
 856  * open attempts will still be much less than the naive approach.
 857  */
 858 int
 859 dag_platform_finddevs(pcap_if_t **devlistp, char *errbuf)
 860 {
 861         char name[12];  /* XXX - pick a size */
 862         int ret = 0;
 863         int c;
 864         char dagname[DAGNAME_BUFSIZE];
 865         int dagstream;
 866         int dagfd;
 867
 868         /* Try all the DAGs 0-9 */
 869         for (c = 0; c < 9; c++) {
 870                 snprintf(name, 12, "dag%d", c);
 871                 if (-1 == dag_parse_name(name, dagname, DAGNAME_BUFSIZE, &dagstream))
 872                 {
 873                         return -1;
 874                 }
 875                 if ( (dagfd = dag_open(dagname)) >= 0 ) {
 876                         if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
 877                                 /*
 878                                  * Failure.
 879                                  */
 880                                 ret = -1;
 881                         }
 882 #ifdef HAVE_DAG_STREAMS_API
 883                         {
 884                                 int stream, rxstreams;
 885                                 rxstreams = dag_rx_get_stream_count(dagfd);
 886                                 for(stream=0;stream<16;stream+=2) {
 887                                         if (0 == dag_attach_stream(dagfd, stream, 0, 0)) {
 888                                                 dag_detach_stream(dagfd, stream);
 889
 890                                                 snprintf(name,  10, "dag%d:%d", c, stream);
 891                                                 if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
 892                                                         /*
 893                                                          * Failure.
 894                                                          */
 895                                                         ret = -1;
 896                                                 }
 897                                         }
 898                                 }
 899                         }
 900 #endif  /* HAVE_DAG_STREAMS_API */
 901                         dag_close(dagfd);
 902                 }
 903
 904         }
 905         return (ret);
 906 }
 907
 908 /*
 909  * Installs the given bpf filter program in the given pcap structure.  There is
 910  * no attempt to store the filter in kernel memory as that is not supported
 911  * with DAG cards.
 912  */
 913 static int
 914 dag_setfilter(pcap_t *p, struct bpf_program *fp)
 915 {
 916         if (!p)
 917                 return -1;
 918         if (!fp) {
 919                 strncpy(p->errbuf, "setfilter: No filter specified",
 920                         sizeof(p->errbuf));
 921                 return -1;
 922         }
 923
 924         /* Make our private copy of the filter */
 925
 926         if (install_bpf_program(p, fp) < 0)
 927                 return -1;
 928
 929         p->md.use_bpf = 0;
 930
 931         return (0);
 932 }
 933
 934 static int
 935 dag_set_datalink(pcap_t *p, int dlt)
 936 {
 937         p->linktype = dlt;
 938
 939         return (0);
 940 }
 941
 942 static int
 943 dag_setnonblock(pcap_t *p, int nonblock, char *errbuf)
 944 {
 945         /*
 946          * Set non-blocking mode on the FD.
 947          * XXX - is that necessary?  If not, don't bother calling it,
 948          * and have a "dag_getnonblock()" function that looks at
 949          * "p->md.dag_offset_flags".
 950          */
 951         if (pcap_setnonblock_fd(p, nonblock, errbuf) < 0)
 952                 return (-1);
 953 #ifdef HAVE_DAG_STREAMS_API
 954         {
 955                 uint32_t mindata;
 956                 struct timeval maxwait;
 957                 struct timeval poll;
 958
 959                 if (dag_get_stream_poll(p->fd, p->md.dag_stream,
 960                                         &mindata, &maxwait, &poll) < 0) {
 961                         snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
 962                         return -1;
 963                 }
 964
 965                 /* Amount of data to collect in Bytes before calling callbacks.
 966                  * Important for efficiency, but can introduce latency
 967                  * at low packet rates if to_ms not set!
 968                  */
 969                 if(nonblock)
 970                         mindata = 0;
 971                 else
 972                         mindata = 65536;
 973
 974                 if (dag_set_stream_poll(p->fd, p->md.dag_stream,
 975                                         mindata, &maxwait, &poll) < 0) {
 976                         snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
 977                         return -1;
 978                 }
 979         }
 980 #endif /* HAVE_DAG_STREAMS_API */
 981         if (nonblock) {
 982                 p->md.dag_offset_flags |= DAGF_NONBLOCK;
 983         } else {
 984                 p->md.dag_offset_flags &= ~DAGF_NONBLOCK;
 985         }
 986         return (0);
 987 }
 988
 989 static int
 990 dag_get_datalink(pcap_t *p)
 991 {
 992         int index=0, dlt_index=0;
 993         uint8_t types[255];
 994
 995         memset(types, 0, 255);
 996
 997         if (p->dlt_list == NULL && (p->dlt_list = malloc(255*sizeof(*(p->dlt_list)))) == NULL) {
 998                 (void)snprintf(p->errbuf, sizeof(p->errbuf), "malloc: %s", pcap_strerror(errno));
 999                 return (-1);
1000         }
1001
1002         p->linktype = 0;
1003
1004 #ifdef HAVE_DAG_GET_STREAM_ERF_TYPES
1005         /* Get list of possible ERF types for this card */
1006         if (dag_get_stream_erf_types(p->fd, p->md.dag_stream, types, 255) < 0) {
1007                 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_stream_erf_types: %s", pcap_strerror(errno));
1008                 return (-1);
1009         }
1010
1011         while (types[index]) {
1012
1013 #elif defined HAVE_DAG_GET_ERF_TYPES
1014         /* Get list of possible ERF types for this card */
1015         if (dag_get_erf_types(p->fd, types, 255) < 0) {
1016                 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_erf_types: %s", pcap_strerror(errno));
1017                 return (-1);
1018         }
1019
1020         while (types[index]) {
1021 #else
1022         /* Check the type through a dagapi call. */
1023         types[index] = dag_linktype(p->fd);
1024
1025         {
1026 #endif
1027                 switch((types[index] & 0x7f)) {
1028
1029                 case TYPE_HDLC_POS:
1030                 case TYPE_COLOR_HDLC_POS:
1031                 case TYPE_DSM_COLOR_HDLC_POS:
1032                 case TYPE_COLOR_HASH_POS:
1033
1034                         if (p->dlt_list != NULL) {
1035                                 p->dlt_list[dlt_index++] = DLT_CHDLC;
1036                                 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1037                                 p->dlt_list[dlt_index++] = DLT_FRELAY;
1038                         }
1039                         if(!p->linktype)
1040                                 p->linktype = DLT_CHDLC;
1041                         break;
1042
1043                 case TYPE_ETH:
1044                 case TYPE_COLOR_ETH:
1045                 case TYPE_DSM_COLOR_ETH:
1046                 case TYPE_COLOR_HASH_ETH:
1047                         /*
1048                          * This is (presumably) a real Ethernet capture; give it a
1049                          * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
1050                          * that an application can let you choose it, in case you're
1051                          * capturing DOCSIS traffic that a Cisco Cable Modem
1052                          * Termination System is putting out onto an Ethernet (it
1053                          * doesn't put an Ethernet header onto the wire, it puts raw
1054                          * DOCSIS frames out on the wire inside the low-level
1055                          * Ethernet framing).
1056                          */
1057                         if (p->dlt_list != NULL) {
1058                                 p->dlt_list[dlt_index++] = DLT_EN10MB;
1059                                 p->dlt_list[dlt_index++] = DLT_DOCSIS;
1060                         }
1061                         if(!p->linktype)
1062                                 p->linktype = DLT_EN10MB;
1063                         break;
1064
1065                 case TYPE_ATM:
1066                 case TYPE_AAL5:
1067                 case TYPE_MC_ATM:
1068                 case TYPE_MC_AAL5:
1069                         if (p->dlt_list != NULL) {
1070                                 p->dlt_list[dlt_index++] = DLT_ATM_RFC1483;
1071                                 p->dlt_list[dlt_index++] = DLT_SUNATM;
1072                         }
1073                         if(!p->linktype)
1074                                 p->linktype = DLT_ATM_RFC1483;
1075                         break;
1076
1077                 case TYPE_COLOR_MC_HDLC_POS:
1078                 case TYPE_MC_HDLC:
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                                 p->dlt_list[dlt_index++] = DLT_MTP2;
1084                                 p->dlt_list[dlt_index++] = DLT_MTP2_WITH_PHDR;
1085                                 p->dlt_list[dlt_index++] = DLT_LAPD;
1086                         }
1087                         if(!p->linktype)
1088                                 p->linktype = DLT_CHDLC;
1089                         break;
1090
1091                 case TYPE_IPV4:
1092                         if(!p->linktype)
1093                                 p->linktype = DLT_RAW;
1094                         break;
1095
1096                 case TYPE_LEGACY:
1097                 case TYPE_MC_RAW:
1098                 case TYPE_MC_RAW_CHANNEL:
1099                 case TYPE_IP_COUNTER:
1100                 case TYPE_TCP_FLOW_COUNTER:
1101                 case TYPE_INFINIBAND:
1102                 case TYPE_IPV6:
1103                 default:
1104                         /* Libpcap cannot deal with these types yet */
1105                         /* Add no DLTs, but still covered by DLT_ERF */
1106                         break;
1107
1108                 } /* switch */
1109                 index++;
1110         }
1111
1112         p->dlt_list[dlt_index++] = DLT_ERF;
1113
1114         p->dlt_count = dlt_index;
1115
1116         if(!p->linktype)
1117                 p->linktype = DLT_ERF;
1118
1119         return p->linktype;
1120 }