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 1.39 2008-04-14 20:40:58 guy Exp $ (LBL)";
  21 #endif
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include <sys/param.h>                  /* optionally get BSD define */
  28
  29 #include <stdlib.h>
  30 #include <string.h>
  31 #include <errno.h>
  32
  33 #include "pcap-int.h"
  34
  35 #include <ctype.h>
  36 #include <netinet/in.h>
  37 #include <sys/mman.h>
  38 #include <sys/socket.h>
  39 #include <sys/types.h>
  40 #include <unistd.h>
  41
  42 struct mbuf;            /* Squelch compiler warnings on some platforms for */
  43 struct rtentry;         /* declarations in <net/if.h> */
  44 #include <net/if.h>
  45
  46 #include "dagnew.h"
  47 #include "dagapi.h"
  48
  49 #include "pcap-dag.h"
  50
  51 #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                         case TYPE_MC_RAW_CHANNEL:
 372                         case TYPE_MC_RAW:
 373                         case TYPE_MC_AAL2:
 374                         case TYPE_COLOR_MC_HDLC_POS:
 375                                 packet_len += 4; /* MC header */
 376                                 break;
 377
 378                         case TYPE_COLOR_HASH_ETH:
 379                         case TYPE_DSM_COLOR_ETH:
 380                         case TYPE_COLOR_ETH:
 381                         case TYPE_ETH:
 382                                 packet_len += 2; /* ETH header */
 383                                 break;
 384                         } /* switch type */
 385
 386                         /* Include ERF extension headers */
 387                         packet_len += (8 * num_ext_hdr);
 388
 389                         if (caplen > packet_len) {
 390                                 caplen = packet_len;
 391                         }
 392                 } else {
 393                         /* Other kind of encapsulation according to the header Type */
 394
 395                         /* Skip over generic ERF header */
 396                         dp += dag_record_size;
 397                         /* Skip over extension headers */
 398                         dp += 8 * num_ext_hdr;
 399
 400                         switch((header->type & 0x7f)) {
 401                         case TYPE_ATM:
 402                         case TYPE_AAL5:
 403                                 if (header->type == TYPE_AAL5) {
 404                                         packet_len = ntohs(header->wlen);
 405                                         caplen = rlen - dag_record_size;
 406                                 }
 407                         case TYPE_MC_ATM:
 408                                 if (header->type == TYPE_MC_ATM) {
 409                                         caplen = packet_len = ATM_CELL_SIZE;
 410                                         dp+=4;
 411                                 }
 412                         case TYPE_MC_AAL5:
 413                                 if (header->type == TYPE_MC_AAL5) {
 414                                         packet_len = ntohs(header->wlen);
 415                                         caplen = rlen - dag_record_size - 4;
 416                                         dp+=4;
 417                                 }
 418                                 if (header->type == TYPE_ATM) {
 419                                         caplen = packet_len = ATM_CELL_SIZE;
 420                                 }
 421                                 if (p->linktype == DLT_SUNATM) {
 422                                         struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
 423                                         unsigned long rawatm;
 424
 425                                         rawatm = ntohl(*((unsigned long *)dp));
 426                                         sunatm->vci = htons((rawatm >>  4) & 0xffff);
 427                                         sunatm->vpi = (rawatm >> 20) & 0x00ff;
 428                                         sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) |
 429                                                 ((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
 430                                                  ((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 :
 431                                                   ((dp[ATM_HDR_SIZE] == 0xaa &&
 432                                                     dp[ATM_HDR_SIZE+1] == 0xaa &&
 433                                                     dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
 434
 435                                 } else {
 436                                         packet_len -= ATM_HDR_SIZE;
 437                                         caplen -= ATM_HDR_SIZE;
 438                                         dp += ATM_HDR_SIZE;
 439                                 }
 440                                 break;
 441
 442                         case TYPE_COLOR_HASH_ETH:
 443                         case TYPE_DSM_COLOR_ETH:
 444                         case TYPE_COLOR_ETH:
 445                         case TYPE_ETH:
 446                                 packet_len = ntohs(header->wlen);
 447                                 packet_len -= (p->md.dag_fcs_bits >> 3);
 448                                 caplen = rlen - dag_record_size - 2;
 449                                 if (caplen > packet_len) {
 450                                         caplen = packet_len;
 451                                 }
 452                                 dp += 2;
 453                                 break;
 454
 455                         case TYPE_COLOR_HASH_POS:
 456                         case TYPE_DSM_COLOR_HDLC_POS:
 457                         case TYPE_COLOR_HDLC_POS:
 458                         case TYPE_HDLC_POS:
 459                                 packet_len = ntohs(header->wlen);
 460                                 packet_len -= (p->md.dag_fcs_bits >> 3);
 461                                 caplen = rlen - dag_record_size;
 462                                 if (caplen > packet_len) {
 463                                         caplen = packet_len;
 464                                 }
 465                                 break;
 466
 467                         case TYPE_COLOR_MC_HDLC_POS:
 468                         case TYPE_MC_HDLC:
 469                                 packet_len = ntohs(header->wlen);
 470                                 packet_len -= (p->md.dag_fcs_bits >> 3);
 471                                 caplen = rlen - dag_record_size - 4;
 472                                 if (caplen > packet_len) {
 473                                         caplen = packet_len;
 474                                 }
 475                                 /* jump the MC_HDLC_HEADER */
 476                                 dp += 4;
 477 #ifdef DLT_MTP2_WITH_PHDR
 478                                 if (p->linktype == DLT_MTP2_WITH_PHDR) {
 479                                         /* Add the MTP2 Pseudo Header */
 480                                         caplen += MTP2_HDR_LEN;
 481                                         packet_len += MTP2_HDR_LEN;
 482
 483                                         TempPkt[MTP2_SENT_OFFSET] = 0;
 484                                         TempPkt[MTP2_ANNEX_A_USED_OFFSET] = MTP2_ANNEX_A_USED_UNKNOWN;
 485                                         *(TempPkt+MTP2_LINK_NUMBER_OFFSET) = ((header->rec.mc_hdlc.mc_header>>16)&0x01);
 486                                         *(TempPkt+MTP2_LINK_NUMBER_OFFSET+1) = ((header->rec.mc_hdlc.mc_header>>24)&0xff);
 487                                         memcpy(TempPkt+MTP2_HDR_LEN, dp, caplen);
 488                                         dp = TempPkt;
 489                                 }
 490 #endif
 491                                 break;
 492
 493                         case TYPE_IPV4:
 494                         case TYPE_IPV6:
 495                                 packet_len = ntohs(header->wlen);
 496                                 caplen = rlen - dag_record_size;
 497                                 if (caplen > packet_len) {
 498                                         caplen = packet_len;
 499                                 }
 500                                 break;
 501
 502                         /* These types have no matching 'native' DLT, but can be used with DLT_ERF above */
 503                         case TYPE_MC_RAW:
 504                         case TYPE_MC_RAW_CHANNEL:
 505                         case TYPE_IP_COUNTER:
 506                         case TYPE_TCP_FLOW_COUNTER:
 507                         case TYPE_INFINIBAND:
 508                         case TYPE_RAW_LINK:
 509                         case TYPE_INFINIBAND_LINK:
 510                         default:
 511                                 /* Unhandled ERF type.
 512                                  * Ignore rather than generating error
 513                                  */
 514                                 continue;
 515                         } /* switch type */
 516
 517                         /* Skip over extension headers */
 518                         caplen -= (8 * num_ext_hdr);
 519
 520                 } /* ERF encapsulation */
 521
 522                 if (caplen > p->snapshot)
 523                         caplen = p->snapshot;
 524
 525                 /* Run the packet filter if there is one. */
 526                 if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
 527
 528                         /* convert between timestamp formats */
 529                         register unsigned long long ts;
 530
 531                         if (IS_BIGENDIAN()) {
 532                                 ts = SWAPLL(header->ts);
 533                         } else {
 534                                 ts = header->ts;
 535                         }
 536
 537                         pcap_header.ts.tv_sec = ts >> 32;
 538                         ts = (ts & 0xffffffffULL) * 1000000;
 539                         ts += 0x80000000; /* rounding */
 540                         pcap_header.ts.tv_usec = ts >> 32;
 541                         if (pcap_header.ts.tv_usec >= 1000000) {
 542                                 pcap_header.ts.tv_usec -= 1000000;
 543                                 pcap_header.ts.tv_sec++;
 544                         }
 545
 546                         /* Fill in our own header data */
 547                         pcap_header.caplen = caplen;
 548                         pcap_header.len = packet_len;
 549
 550                         /* Count the packet. */
 551                         p->md.stat.ps_recv++;
 552
 553                         /* Call the user supplied callback function */
 554                         callback(user, &pcap_header, dp);
 555
 556                         /* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
 557                         processed++;
 558                         if (processed == cnt && cnt > 0)
 559                         {
 560                                 /* Reached the user-specified limit. */
 561                                 return cnt;
 562                         }
 563                 }
 564         }
 565
 566         return processed;
 567 }
 568
 569 static int
 570 dag_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
 571 {
 572         strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
 573             PCAP_ERRBUF_SIZE);
 574         return (-1);
 575 }
 576
 577 /*
 578  *  Get a handle for a live capture from the given DAG device.  Passing a NULL
 579  *  device will result in a failure.  The promisc flag is ignored because DAG
 580  *  cards are always promiscuous.  The to_ms parameter is used in setting the
 581  *  API polling parameters.
 582  *
 583  *  snaplen is now also ignored, until we get per-stream slen support. Set
 584  *  slen with approprite DAG tool BEFORE pcap_activate().
 585  *
 586  *  See also pcap(3).
 587  */
 588 static int dag_activate(pcap_t* handle)
 589 {
 590 #if 0
 591         char conf[30]; /* dag configure string */
 592 #endif
 593         char *s;
 594         int n;
 595         daginf_t* daginf;
 596         char * newDev = NULL;
 597         char * device = handle->opt.source;
 598 #ifdef HAVE_DAG_STREAMS_API
 599         uint32_t mindata;
 600         struct timeval maxwait;
 601         struct timeval poll;
 602 #endif
 603
 604         if (device == NULL) {
 605                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "device is NULL: %s", pcap_strerror(errno));
 606                 return -1;
 607         }
 608
 609         /* Initialize some components of the pcap structure. */
 610
 611 #ifdef HAVE_DAG_STREAMS_API
 612         newDev = (char *)malloc(strlen(device) + 16);
 613         if (newDev == NULL) {
 614                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
 615                 goto fail;
 616         }
 617
 618         /* Parse input name to get dag device and stream number if provided */
 619         if (dag_parse_name(device, newDev, strlen(device) + 16, &handle->md.dag_stream) < 0) {
 620                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: %s\n", pcap_strerror(errno));
 621                 goto fail;
 622         }
 623         device = newDev;
 624
 625         if (handle->md.dag_stream%2) {
 626                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: tx (even numbered) streams not supported for capture\n");
 627                 goto fail;
 628         }
 629 #else
 630         if (strncmp(device, "/dev/", 5) != 0) {
 631                 newDev = (char *)malloc(strlen(device) + 5);
 632                 if (newDev == NULL) {
 633                         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
 634                         goto fail;
 635                 }
 636                 strcpy(newDev, "/dev/");
 637                 strcat(newDev, device);
 638                 device = newDev;
 639         }
 640 #endif /* HAVE_DAG_STREAMS_API */
 641
 642         /* setup device parameters */
 643         if((handle->fd = dag_open((char *)device)) < 0) {
 644                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_open %s: %s", device, pcap_strerror(errno));
 645                 goto fail;
 646         }
 647
 648 #ifdef HAVE_DAG_STREAMS_API
 649         /* Open requested stream. Can fail if already locked or on error */
 650         if (dag_attach_stream(handle->fd, handle->md.dag_stream, 0, 0) < 0) {
 651                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_attach_stream: %s\n", pcap_strerror(errno));
 652                 goto failclose;
 653         }
 654
 655         /* Set up default poll parameters for stream
 656          * Can be overridden by pcap_set_nonblock()
 657          */
 658         if (dag_get_stream_poll(handle->fd, handle->md.dag_stream,
 659                                 &mindata, &maxwait, &poll) < 0) {
 660                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
 661                 goto faildetach;
 662         }
 663
 664         /* Amount of data to collect in Bytes before calling callbacks.
 665          * Important for efficiency, but can introduce latency
 666          * at low packet rates if to_ms not set!
 667          */
 668         mindata = 65536;
 669
 670         /* Obey md.timeout (was to_ms) if supplied. This is a good idea!
 671          * Recommend 10-100ms. Calls will time out even if no data arrived.
 672          */
 673         maxwait.tv_sec = handle->md.timeout/1000;
 674         maxwait.tv_usec = (handle->md.timeout%1000) * 1000;
 675
 676         if (dag_set_stream_poll(handle->fd, handle->md.dag_stream,
 677                                 mindata, &maxwait, &poll) < 0) {
 678                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
 679                 goto faildetach;
 680         }
 681
 682 #else
 683         if((handle->md.dag_mem_base = dag_mmap(handle->fd)) == MAP_FAILED) {
 684                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_mmap %s: %s\n", device, pcap_strerror(errno));
 685                 goto failclose;
 686         }
 687
 688 #endif /* HAVE_DAG_STREAMS_API */
 689
 690         /* XXX Not calling dag_configure() to set slen; this is unsafe in
 691          * multi-stream environments as the gpp config is global.
 692          * Once the firmware provides 'per-stream slen' this can be supported
 693          * again via the Config API without side-effects */
 694 #if 0
 695         /* set the card snap length to the specified snaplen parameter */
 696         /* This is a really bad idea, as different cards have different
 697          * valid slen ranges. Should fix in Config API. */
 698         if (handle->snapshot == 0 || handle->snapshot > MAX_DAG_SNAPLEN) {
 699                 handle->snapshot = MAX_DAG_SNAPLEN;
 700         } else if (snaplen < MIN_DAG_SNAPLEN) {
 701                 handle->snapshot = MIN_DAG_SNAPLEN;
 702         }
 703         /* snap len has to be a multiple of 4 */
 704         snprintf(conf, 30, "varlen slen=%d", (snaplen + 3) & ~3);
 705
 706         if(dag_configure(handle->fd, conf) < 0) {
 707                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_configure %s: %s\n", device, pcap_strerror(errno));
 708                 goto faildetach;
 709         }
 710 #endif
 711
 712 #ifdef HAVE_DAG_STREAMS_API
 713         if(dag_start_stream(handle->fd, handle->md.dag_stream) < 0) {
 714                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start_stream %s: %s\n", device, pcap_strerror(errno));
 715                 goto faildetach;
 716         }
 717 #else
 718         if(dag_start(handle->fd) < 0) {
 719                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start %s: %s\n", device, pcap_strerror(errno));
 720                 goto failclose;
 721         }
 722 #endif /* HAVE_DAG_STREAMS_API */
 723
 724         /*
 725          * Important! You have to ensure bottom is properly
 726          * initialized to zero on startup, it won't give you
 727          * a compiler warning if you make this mistake!
 728          */
 729         handle->md.dag_mem_bottom = 0;
 730         handle->md.dag_mem_top = 0;
 731
 732         /*
 733          * Find out how many FCS bits we should strip.
 734          * First, query the card to see if it strips the FCS.
 735          */
 736         daginf = dag_info(handle->fd);
 737         if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code)) {
 738                 /* DAG 4.2S and 4.23S already strip the FCS.  Stripping the final word again truncates the packet. */
 739                 handle->md.dag_fcs_bits = 0;
 740
 741                 /* Note that no FCS will be supplied. */
 742                 handle->linktype_ext = LT_FCS_DATALINK_EXT(0);
 743         } else {
 744                 /*
 745                  * Start out assuming it's 32 bits.
 746                  */
 747                 handle->md.dag_fcs_bits = 32;
 748
 749                 /* Allow an environment variable to override. */
 750                 if ((s = getenv("ERF_FCS_BITS")) != NULL) {
 751                         if ((n = atoi(s)) == 0 || n == 16 || n == 32) {
 752                                 handle->md.dag_fcs_bits = n;
 753                         } else {
 754                                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 755                                         "pcap_activate %s: bad ERF_FCS_BITS value (%d) in environment\n", device, n);
 756                                 goto failstop;
 757                         }
 758                 }
 759
 760                 /*
 761                  * Did the user request that they not be stripped?
 762                  */
 763                 if ((s = getenv("ERF_DONT_STRIP_FCS")) != NULL) {
 764                         /* Yes.  Note the number of bytes that will be
 765                            supplied. */
 766                         handle->linktype_ext = LT_FCS_DATALINK_EXT(handle->md.dag_fcs_bits/16);
 767
 768                         /* And don't strip them. */
 769                         handle->md.dag_fcs_bits = 0;
 770                 }
 771         }
 772
 773         handle->md.dag_timeout  = handle->md.timeout;
 774
 775         handle->linktype = -1;
 776         if (dag_get_datalink(handle) < 0)
 777                 goto failstop;
 778
 779         handle->bufsize = 0;
 780
 781         if (new_pcap_dag(handle) < 0) {
 782                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "new_pcap_dag %s: %s\n", device, pcap_strerror(errno));
 783                 goto failstop;
 784         }
 785
 786         /*
 787          * "select()" and "poll()" don't work on DAG device descriptors.
 788          */
 789         handle->selectable_fd = -1;
 790
 791         if (newDev != NULL) {
 792                 free((char *)newDev);
 793         }
 794
 795         handle->read_op = dag_read;
 796         handle->inject_op = dag_inject;
 797         handle->setfilter_op = dag_setfilter;
 798         handle->setdirection_op = NULL; /* Not implemented.*/
 799         handle->set_datalink_op = dag_set_datalink;
 800         handle->getnonblock_op = pcap_getnonblock_fd;
 801         handle->setnonblock_op = dag_setnonblock;
 802         handle->stats_op = dag_stats;
 803         handle->cleanup_op = dag_platform_cleanup;
 804         handle->md.stat.ps_drop = 0;
 805         handle->md.stat.ps_recv = 0;
 806         handle->md.stat.ps_ifdrop = 0;
 807         return 0;
 808
 809 #ifdef HAVE_DAG_STREAMS_API
 810 failstop:
 811         if (dag_stop_stream(handle->fd, handle->md.dag_stream) < 0) {
 812                 fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
 813         }
 814
 815 faildetach:
 816         if (dag_detach_stream(handle->fd, handle->md.dag_stream) < 0)
 817                 fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
 818 #else
 819 failstop:
 820         if (dag_stop(handle->fd) < 0)
 821                 fprintf(stderr,"dag_stop: %s\n", strerror(errno));
 822 #endif /* HAVE_DAG_STREAMS_API */
 823
 824 failclose:
 825         if (dag_close(handle->fd) < 0)
 826                 fprintf(stderr,"dag_close: %s\n", strerror(errno));
 827         delete_pcap_dag(handle);
 828
 829 fail:
 830         pcap_cleanup_live_common(handle);
 831         if (newDev != NULL) {
 832                 free((char *)newDev);
 833         }
 834
 835         return PCAP_ERROR;
 836 }
 837
 838 pcap_t *dag_create(const char *device, char *ebuf)
 839 {
 840         pcap_t *p;
 841
 842         p = pcap_create_common(device, ebuf);
 843         if (p == NULL)
 844                 return NULL;
 845
 846         p->activate_op = dag_activate;
 847         return p;
 848 }
 849
 850 static int
 851 dag_stats(pcap_t *p, struct pcap_stat *ps) {
 852         /* This needs to be filled out correctly.  Hopefully a dagapi call will
 853                  provide all necessary information.
 854         */
 855         /*p->md.stat.ps_recv = 0;*/
 856         /*p->md.stat.ps_drop = 0;*/
 857
 858         *ps = p->md.stat;
 859
 860         return 0;
 861 }
 862
 863 /*
 864  * Previously we just generated a list of all possible names and let
 865  * pcap_add_if() attempt to open each one, but with streams this adds up
 866  * to 81 possibilities which is inefficient.
 867  *
 868  * Since we know more about the devices we can prune the tree here.
 869  * pcap_add_if() will still retest each device but the total number of
 870  * open attempts will still be much less than the naive approach.
 871  */
 872 int
 873 dag_platform_finddevs(pcap_if_t **devlistp, char *errbuf)
 874 {
 875         char name[12];  /* XXX - pick a size */
 876         int ret = 0;
 877         int c;
 878         char dagname[DAGNAME_BUFSIZE];
 879         int dagstream;
 880         int dagfd;
 881
 882         /* Try all the DAGs 0-9 */
 883         for (c = 0; c < 9; c++) {
 884                 snprintf(name, 12, "dag%d", c);
 885                 if (-1 == dag_parse_name(name, dagname, DAGNAME_BUFSIZE, &dagstream))
 886                 {
 887                         return -1;
 888                 }
 889                 if ( (dagfd = dag_open(dagname)) >= 0 ) {
 890                         if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
 891                                 /*
 892                                  * Failure.
 893                                  */
 894                                 ret = -1;
 895                         }
 896 #ifdef HAVE_DAG_STREAMS_API
 897                         {
 898                                 int stream, rxstreams;
 899                                 rxstreams = dag_rx_get_stream_count(dagfd);
 900                                 for(stream=0;stream<16;stream+=2) {
 901                                         if (0 == dag_attach_stream(dagfd, stream, 0, 0)) {
 902                                                 dag_detach_stream(dagfd, stream);
 903
 904                                                 snprintf(name,  10, "dag%d:%d", c, stream);
 905                                                 if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
 906                                                         /*
 907                                                          * Failure.
 908                                                          */
 909                                                         ret = -1;
 910                                                 }
 911                                         }
 912                                 }
 913                         }
 914 #endif  /* HAVE_DAG_STREAMS_API */
 915                         dag_close(dagfd);
 916                 }
 917
 918         }
 919         return (ret);
 920 }
 921
 922 /*
 923  * Installs the given bpf filter program in the given pcap structure.  There is
 924  * no attempt to store the filter in kernel memory as that is not supported
 925  * with DAG cards.
 926  */
 927 static int
 928 dag_setfilter(pcap_t *p, struct bpf_program *fp)
 929 {
 930         if (!p)
 931                 return -1;
 932         if (!fp) {
 933                 strncpy(p->errbuf, "setfilter: No filter specified",
 934                         sizeof(p->errbuf));
 935                 return -1;
 936         }
 937
 938         /* Make our private copy of the filter */
 939
 940         if (install_bpf_program(p, fp) < 0)
 941                 return -1;
 942
 943         p->md.use_bpf = 0;
 944
 945         return (0);
 946 }
 947
 948 static int
 949 dag_set_datalink(pcap_t *p, int dlt)
 950 {
 951         p->linktype = dlt;
 952
 953         return (0);
 954 }
 955
 956 static int
 957 dag_setnonblock(pcap_t *p, int nonblock, char *errbuf)
 958 {
 959         /*
 960          * Set non-blocking mode on the FD.
 961          * XXX - is that necessary?  If not, don't bother calling it,
 962          * and have a "dag_getnonblock()" function that looks at
 963          * "p->md.dag_offset_flags".
 964          */
 965         if (pcap_setnonblock_fd(p, nonblock, errbuf) < 0)
 966                 return (-1);
 967 #ifdef HAVE_DAG_STREAMS_API
 968         {
 969                 uint32_t mindata;
 970                 struct timeval maxwait;
 971                 struct timeval poll;
 972
 973                 if (dag_get_stream_poll(p->fd, p->md.dag_stream,
 974                                         &mindata, &maxwait, &poll) < 0) {
 975                         snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
 976                         return -1;
 977                 }
 978
 979                 /* Amount of data to collect in Bytes before calling callbacks.
 980                  * Important for efficiency, but can introduce latency
 981                  * at low packet rates if to_ms not set!
 982                  */
 983                 if(nonblock)
 984                         mindata = 0;
 985                 else
 986                         mindata = 65536;
 987
 988                 if (dag_set_stream_poll(p->fd, p->md.dag_stream,
 989                                         mindata, &maxwait, &poll) < 0) {
 990                         snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
 991                         return -1;
 992                 }
 993         }
 994 #endif /* HAVE_DAG_STREAMS_API */
 995         if (nonblock) {
 996                 p->md.dag_offset_flags |= DAGF_NONBLOCK;
 997         } else {
 998                 p->md.dag_offset_flags &= ~DAGF_NONBLOCK;
 999         }
1000         return (0);
1001 }
1002
1003 static int
1004 dag_get_datalink(pcap_t *p)
1005 {
1006         int index=0, dlt_index=0;
1007         uint8_t types[255];
1008
1009         memset(types, 0, 255);
1010
1011         if (p->dlt_list == NULL && (p->dlt_list = malloc(255*sizeof(*(p->dlt_list)))) == NULL) {
1012                 (void)snprintf(p->errbuf, sizeof(p->errbuf), "malloc: %s", pcap_strerror(errno));
1013                 return (-1);
1014         }
1015
1016         p->linktype = 0;
1017
1018 #ifdef HAVE_DAG_GET_STREAM_ERF_TYPES
1019         /* Get list of possible ERF types for this card */
1020         if (dag_get_stream_erf_types(p->fd, p->md.dag_stream, types, 255) < 0) {
1021                 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_stream_erf_types: %s", pcap_strerror(errno));
1022                 return (-1);
1023         }
1024
1025         while (types[index]) {
1026
1027 #elif defined HAVE_DAG_GET_ERF_TYPES
1028         /* Get list of possible ERF types for this card */
1029         if (dag_get_erf_types(p->fd, types, 255) < 0) {
1030                 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_erf_types: %s", pcap_strerror(errno));
1031                 return (-1);
1032         }
1033
1034         while (types[index]) {
1035 #else
1036         /* Check the type through a dagapi call. */
1037         types[index] = dag_linktype(p->fd);
1038
1039         {
1040 #endif
1041                 switch((types[index] & 0x7f)) {
1042
1043                 case TYPE_HDLC_POS:
1044                 case TYPE_COLOR_HDLC_POS:
1045                 case TYPE_DSM_COLOR_HDLC_POS:
1046                 case TYPE_COLOR_HASH_POS:
1047
1048                         if (p->dlt_list != NULL) {
1049                                 p->dlt_list[dlt_index++] = DLT_CHDLC;
1050                                 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1051                                 p->dlt_list[dlt_index++] = DLT_FRELAY;
1052                         }
1053                         if(!p->linktype)
1054                                 p->linktype = DLT_CHDLC;
1055                         break;
1056
1057                 case TYPE_ETH:
1058                 case TYPE_COLOR_ETH:
1059                 case TYPE_DSM_COLOR_ETH:
1060                 case TYPE_COLOR_HASH_ETH:
1061                         /*
1062                          * This is (presumably) a real Ethernet capture; give it a
1063                          * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
1064                          * that an application can let you choose it, in case you're
1065                          * capturing DOCSIS traffic that a Cisco Cable Modem
1066                          * Termination System is putting out onto an Ethernet (it
1067                          * doesn't put an Ethernet header onto the wire, it puts raw
1068                          * DOCSIS frames out on the wire inside the low-level
1069                          * Ethernet framing).
1070                          */
1071                         if (p->dlt_list != NULL) {
1072                                 p->dlt_list[dlt_index++] = DLT_EN10MB;
1073                                 p->dlt_list[dlt_index++] = DLT_DOCSIS;
1074                         }
1075                         if(!p->linktype)
1076                                 p->linktype = DLT_EN10MB;
1077                         break;
1078
1079                 case TYPE_ATM:
1080                 case TYPE_AAL5:
1081                 case TYPE_MC_ATM:
1082                 case TYPE_MC_AAL5:
1083                         if (p->dlt_list != NULL) {
1084                                 p->dlt_list[dlt_index++] = DLT_ATM_RFC1483;
1085                                 p->dlt_list[dlt_index++] = DLT_SUNATM;
1086                         }
1087                         if(!p->linktype)
1088                                 p->linktype = DLT_ATM_RFC1483;
1089                         break;
1090
1091                 case TYPE_COLOR_MC_HDLC_POS:
1092                 case TYPE_MC_HDLC:
1093                         if (p->dlt_list != NULL) {
1094                                 p->dlt_list[dlt_index++] = DLT_CHDLC;
1095                                 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1096                                 p->dlt_list[dlt_index++] = DLT_FRELAY;
1097                                 p->dlt_list[dlt_index++] = DLT_MTP2;
1098                                 p->dlt_list[dlt_index++] = DLT_MTP2_WITH_PHDR;
1099                                 p->dlt_list[dlt_index++] = DLT_LAPD;
1100                         }
1101                         if(!p->linktype)
1102                                 p->linktype = DLT_CHDLC;
1103                         break;
1104
1105                 case TYPE_IPV4:
1106                 case TYPE_IPV6:
1107                         if(!p->linktype)
1108                                 p->linktype = DLT_RAW;
1109                         break;
1110
1111                 case TYPE_LEGACY:
1112                 case TYPE_MC_RAW:
1113                 case TYPE_MC_RAW_CHANNEL:
1114                 case TYPE_IP_COUNTER:
1115                 case TYPE_TCP_FLOW_COUNTER:
1116                 case TYPE_INFINIBAND:
1117                 case TYPE_RAW_LINK:
1118                 case TYPE_INFINIBAND_LINK:
1119                 default:
1120                         /* Libpcap cannot deal with these types yet */
1121                         /* Add no 'native' DLTs, but still covered by DLT_ERF */
1122                         break;
1123
1124                 } /* switch */
1125                 index++;
1126         }
1127
1128         p->dlt_list[dlt_index++] = DLT_ERF;
1129
1130         p->dlt_count = dlt_index;
1131
1132         if(!p->linktype)
1133                 p->linktype = DLT_ERF;
1134
1135         return p->linktype;
1136 }