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 #ifdef HAVE_CONFIG_H
  19 #include "config.h"
  20 #endif
  21
  22 #include <sys/param.h>                  /* optionally get BSD define */
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <errno.h>
  27
  28 #include "pcap-int.h"
  29
  30 #include <ctype.h>
  31 #include <netinet/in.h>
  32 #include <sys/mman.h>
  33 #include <sys/socket.h>
  34 #include <sys/types.h>
  35 #include <unistd.h>
  36
  37 struct mbuf;            /* Squelch compiler warnings on some platforms for */
  38 struct rtentry;         /* declarations in <net/if.h> */
  39 #include <net/if.h>
  40
  41 #include "dagnew.h"
  42 #include "dagapi.h"
  43
  44 #include "pcap-dag.h"
  45
  46 /*
  47  * DAG devices have names beginning with "dag", followed by a number
  48  * from 0 to DAG_MAX_BOARDS, then optionally a colon and a stream number
  49  * from 0 to DAG_STREAM_MAX.
  50  */
  51 #ifndef DAG_MAX_BOARDS
  52 #define DAG_MAX_BOARDS 32
  53 #endif
  54
  55 #define ATM_CELL_SIZE           52
  56 #define ATM_HDR_SIZE            4
  57
  58 /*
  59  * A header containing additional MTP information.
  60  */
  61 #define MTP2_SENT_OFFSET                0       /* 1 byte */
  62 #define MTP2_ANNEX_A_USED_OFFSET        1       /* 1 byte */
  63 #define MTP2_LINK_NUMBER_OFFSET         2       /* 2 bytes */
  64 #define MTP2_HDR_LEN                    4       /* length of the header */
  65
  66 #define MTP2_ANNEX_A_NOT_USED      0
  67 #define MTP2_ANNEX_A_USED          1
  68 #define MTP2_ANNEX_A_USED_UNKNOWN  2
  69
  70 /* SunATM pseudo header */
  71 struct sunatm_hdr {
  72         unsigned char   flags;          /* destination and traffic type */
  73         unsigned char   vpi;            /* VPI */
  74         unsigned short  vci;            /* VCI */
  75 };
  76
  77 /*
  78  * Private data for capturing on DAG devices.
  79  */
  80 struct pcap_dag {
  81         struct pcap_stat stat;
  82 #ifdef HAVE_DAG_STREAMS_API
  83         u_char  *dag_mem_bottom;        /* DAG card current memory bottom pointer */
  84         u_char  *dag_mem_top;   /* DAG card current memory top pointer */
  85 #else /* HAVE_DAG_STREAMS_API */
  86         void    *dag_mem_base;  /* DAG card memory base address */
  87         u_int   dag_mem_bottom; /* DAG card current memory bottom offset */
  88         u_int   dag_mem_top;    /* DAG card current memory top offset */
  89 #endif /* HAVE_DAG_STREAMS_API */
  90         int     dag_fcs_bits;   /* Number of checksum bits from link layer */
  91         int     dag_offset_flags; /* Flags to pass to dag_offset(). */
  92         int     dag_stream;     /* DAG stream number */
  93         int     dag_timeout;    /* timeout specified to pcap_open_live.
  94                                  * Same as in linux above, introduce
  95                                  * generally? */
  96 };
  97
  98 typedef struct pcap_dag_node {
  99         struct pcap_dag_node *next;
 100         pcap_t *p;
 101         pid_t pid;
 102 } pcap_dag_node_t;
 103
 104 static pcap_dag_node_t *pcap_dags = NULL;
 105 static int atexit_handler_installed = 0;
 106 static const unsigned short endian_test_word = 0x0100;
 107
 108 #define IS_BIGENDIAN() (*((unsigned char *)&endian_test_word))
 109
 110 #define MAX_DAG_PACKET 65536
 111
 112 static unsigned char TempPkt[MAX_DAG_PACKET];
 113
 114 static int dag_setfilter(pcap_t *p, struct bpf_program *fp);
 115 static int dag_stats(pcap_t *p, struct pcap_stat *ps);
 116 static int dag_set_datalink(pcap_t *p, int dlt);
 117 static int dag_get_datalink(pcap_t *p);
 118 static int dag_setnonblock(pcap_t *p, int nonblock, char *errbuf);
 119
 120 static void
 121 delete_pcap_dag(pcap_t *p)
 122 {
 123         pcap_dag_node_t *curr = NULL, *prev = NULL;
 124
 125         for (prev = NULL, curr = pcap_dags; curr != NULL && curr->p != p; prev = curr, curr = curr->next) {
 126                 /* empty */
 127         }
 128
 129         if (curr != NULL && curr->p == p) {
 130                 if (prev != NULL) {
 131                         prev->next = curr->next;
 132                 } else {
 133                         pcap_dags = curr->next;
 134                 }
 135         }
 136 }
 137
 138 /*
 139  * Performs a graceful shutdown of the DAG card, frees dynamic memory held
 140  * in the pcap_t structure, and closes the file descriptor for the DAG card.
 141  */
 142
 143 static void
 144 dag_platform_cleanup(pcap_t *p)
 145 {
 146         struct pcap_dag *pd;
 147
 148         if (p != NULL) {
 149                 pd = p->priv;
 150 #ifdef HAVE_DAG_STREAMS_API
 151                 if(dag_stop_stream(p->fd, pd->dag_stream) < 0)
 152                         fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
 153
 154                 if(dag_detach_stream(p->fd, pd->dag_stream) < 0)
 155                         fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
 156 #else
 157                 if(dag_stop(p->fd) < 0)
 158                         fprintf(stderr,"dag_stop: %s\n", strerror(errno));
 159 #endif /* HAVE_DAG_STREAMS_API */
 160                 if(p->fd != -1) {
 161                         if(dag_close(p->fd) < 0)
 162                                 fprintf(stderr,"dag_close: %s\n", strerror(errno));
 163                         p->fd = -1;
 164                 }
 165                 delete_pcap_dag(p);
 166                 pcap_cleanup_live_common(p);
 167         }
 168         /* Note: don't need to call close(p->fd) here as dag_close(p->fd) does this. */
 169 }
 170
 171 static void
 172 atexit_handler(void)
 173 {
 174         while (pcap_dags != NULL) {
 175                 if (pcap_dags->pid == getpid()) {
 176                         dag_platform_cleanup(pcap_dags->p);
 177                 } else {
 178                         delete_pcap_dag(pcap_dags->p);
 179                 }
 180         }
 181 }
 182
 183 static int
 184 new_pcap_dag(pcap_t *p)
 185 {
 186         pcap_dag_node_t *node = NULL;
 187
 188         if ((node = malloc(sizeof(pcap_dag_node_t))) == NULL) {
 189                 return -1;
 190         }
 191
 192         if (!atexit_handler_installed) {
 193                 atexit(atexit_handler);
 194                 atexit_handler_installed = 1;
 195         }
 196
 197         node->next = pcap_dags;
 198         node->p = p;
 199         node->pid = getpid();
 200
 201         pcap_dags = node;
 202
 203         return 0;
 204 }
 205
 206 static unsigned int
 207 dag_erf_ext_header_count(uint8_t * erf, size_t len)
 208 {
 209         uint32_t hdr_num = 0;
 210         uint8_t  hdr_type;
 211
 212         /* basic sanity checks */
 213         if ( erf == NULL )
 214                 return 0;
 215         if ( len < 16 )
 216                 return 0;
 217
 218         /* check if we have any extension headers */
 219         if ( (erf[8] & 0x80) == 0x00 )
 220                 return 0;
 221
 222         /* loop over the extension headers */
 223         do {
 224
 225                 /* sanity check we have enough bytes */
 226                 if ( len < (24 + (hdr_num * 8)) )
 227                         return hdr_num;
 228
 229                 /* get the header type */
 230                 hdr_type = erf[(16 + (hdr_num * 8))];
 231                 hdr_num++;
 232
 233         } while ( hdr_type & 0x80 );
 234
 235         return hdr_num;
 236 }
 237
 238 /*
 239  *  Read at most max_packets from the capture stream and call the callback
 240  *  for each of them. Returns the number of packets handled, -1 if an
 241  *  error occured, or -2 if we were told to break out of the loop.
 242  */
 243 static int
 244 dag_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
 245 {
 246         struct pcap_dag *pd = p->priv;
 247         unsigned int processed = 0;
 248         int flags = pd->dag_offset_flags;
 249         unsigned int nonblocking = flags & DAGF_NONBLOCK;
 250         unsigned int num_ext_hdr = 0;
 251
 252         /* Get the next bufferful of packets (if necessary). */
 253         while (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size) {
 254
 255                 /*
 256                  * Has "pcap_breakloop()" been called?
 257                  */
 258                 if (p->break_loop) {
 259                         /*
 260                          * Yes - clear the flag that indicates that
 261                          * it has, and return -2 to indicate that
 262                          * we were told to break out of the loop.
 263                          */
 264                         p->break_loop = 0;
 265                         return -2;
 266                 }
 267
 268 #ifdef HAVE_DAG_STREAMS_API
 269                 /* dag_advance_stream() will block (unless nonblock is called)
 270                  * until 64kB of data has accumulated.
 271                  * If to_ms is set, it will timeout before 64kB has accumulated.
 272                  * We wait for 64kB because processing a few packets at a time
 273                  * can cause problems at high packet rates (>200kpps) due
 274                  * to inefficiencies.
 275                  * This does mean if to_ms is not specified the capture may 'hang'
 276                  * for long periods if the data rate is extremely slow (<64kB/sec)
 277                  * If non-block is specified it will return immediately. The user
 278                  * is then responsible for efficiency.
 279                  */
 280                 if ( NULL == (pd->dag_mem_top = dag_advance_stream(p->fd, pd->dag_stream, &(pd->dag_mem_bottom))) ) {
 281                      return -1;
 282                 }
 283 #else
 284                 /* dag_offset does not support timeouts */
 285                 pd->dag_mem_top = dag_offset(p->fd, &(pd->dag_mem_bottom), flags);
 286 #endif /* HAVE_DAG_STREAMS_API */
 287
 288                 if (nonblocking && (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size))
 289                 {
 290                         /* Pcap is configured to process only available packets, and there aren't any, return immediately. */
 291                         return 0;
 292                 }
 293
 294                 if(!nonblocking &&
 295                    pd->dag_timeout &&
 296                    (pd->dag_mem_top - pd->dag_mem_bottom < dag_record_size))
 297                 {
 298                         /* Blocking mode, but timeout set and no data has arrived, return anyway.*/
 299                         return 0;
 300                 }
 301
 302         }
 303
 304         /* Process the packets. */
 305         while (pd->dag_mem_top - pd->dag_mem_bottom >= dag_record_size) {
 306
 307                 unsigned short packet_len = 0;
 308                 int caplen = 0;
 309                 struct pcap_pkthdr      pcap_header;
 310
 311 #ifdef HAVE_DAG_STREAMS_API
 312                 dag_record_t *header = (dag_record_t *)(pd->dag_mem_bottom);
 313 #else
 314                 dag_record_t *header = (dag_record_t *)(pd->dag_mem_base + pd->dag_mem_bottom);
 315 #endif /* HAVE_DAG_STREAMS_API */
 316
 317                 u_char *dp = ((u_char *)header); /* + dag_record_size; */
 318                 unsigned short rlen;
 319
 320                 /*
 321                  * Has "pcap_breakloop()" been called?
 322                  */
 323                 if (p->break_loop) {
 324                         /*
 325                          * Yes - clear the flag that indicates that
 326                          * it has, and return -2 to indicate that
 327                          * we were told to break out of the loop.
 328                          */
 329                         p->break_loop = 0;
 330                         return -2;
 331                 }
 332
 333                 rlen = ntohs(header->rlen);
 334                 if (rlen < dag_record_size)
 335                 {
 336                         strncpy(p->errbuf, "dag_read: record too small", PCAP_ERRBUF_SIZE);
 337                         return -1;
 338                 }
 339                 pd->dag_mem_bottom += rlen;
 340
 341                 /* Count lost packets. */
 342                 switch((header->type & 0x7f)) {
 343                         /* in these types the color value overwrites the lctr */
 344                 case TYPE_COLOR_HDLC_POS:
 345                 case TYPE_COLOR_ETH:
 346                 case TYPE_DSM_COLOR_HDLC_POS:
 347                 case TYPE_DSM_COLOR_ETH:
 348                 case TYPE_COLOR_MC_HDLC_POS:
 349                 case TYPE_COLOR_HASH_ETH:
 350                 case TYPE_COLOR_HASH_POS:
 351                         break;
 352
 353                 default:
 354                         if (header->lctr) {
 355                                 if (pd->stat.ps_drop > (UINT_MAX - ntohs(header->lctr))) {
 356                                         pd->stat.ps_drop = UINT_MAX;
 357                                 } else {
 358                                         pd->stat.ps_drop += ntohs(header->lctr);
 359                                 }
 360                         }
 361                 }
 362
 363                 if ((header->type & 0x7f) == TYPE_PAD) {
 364                         continue;
 365                 }
 366
 367                 num_ext_hdr = dag_erf_ext_header_count(dp, rlen);
 368
 369                 /* ERF encapsulation */
 370                 /* The Extensible Record Format is not dropped for this kind of encapsulation,
 371                  * and will be handled as a pseudo header by the decoding application.
 372                  * The information carried in the ERF header and in the optional subheader (if present)
 373                  * could be merged with the libpcap information, to offer a better decoding.
 374                  * The packet length is
 375                  * o the length of the packet on the link (header->wlen),
 376                  * o plus the length of the ERF header (dag_record_size), as the length of the
 377                  *   pseudo header will be adjusted during the decoding,
 378                  * o plus the length of the optional subheader (if present).
 379                  *
 380                  * The capture length is header.rlen and the byte stuffing for alignment will be dropped
 381                  * if the capture length is greater than the packet length.
 382                  */
 383                 if (p->linktype == DLT_ERF) {
 384                         packet_len = ntohs(header->wlen) + dag_record_size;
 385                         caplen = rlen;
 386                         switch ((header->type & 0x7f)) {
 387                         case TYPE_MC_AAL5:
 388                         case TYPE_MC_ATM:
 389                         case TYPE_MC_HDLC:
 390                         case TYPE_MC_RAW_CHANNEL:
 391                         case TYPE_MC_RAW:
 392                         case TYPE_MC_AAL2:
 393                         case TYPE_COLOR_MC_HDLC_POS:
 394                                 packet_len += 4; /* MC header */
 395                                 break;
 396
 397                         case TYPE_COLOR_HASH_ETH:
 398                         case TYPE_DSM_COLOR_ETH:
 399                         case TYPE_COLOR_ETH:
 400                         case TYPE_ETH:
 401                                 packet_len += 2; /* ETH header */
 402                                 break;
 403                         } /* switch type */
 404
 405                         /* Include ERF extension headers */
 406                         packet_len += (8 * num_ext_hdr);
 407
 408                         if (caplen > packet_len) {
 409                                 caplen = packet_len;
 410                         }
 411                 } else {
 412                         /* Other kind of encapsulation according to the header Type */
 413
 414                         /* Skip over generic ERF header */
 415                         dp += dag_record_size;
 416                         /* Skip over extension headers */
 417                         dp += 8 * num_ext_hdr;
 418
 419                         switch((header->type & 0x7f)) {
 420                         case TYPE_ATM:
 421                         case TYPE_AAL5:
 422                                 if (header->type == TYPE_AAL5) {
 423                                         packet_len = ntohs(header->wlen);
 424                                         caplen = rlen - dag_record_size;
 425                                 }
 426                         case TYPE_MC_ATM:
 427                                 if (header->type == TYPE_MC_ATM) {
 428                                         caplen = packet_len = ATM_CELL_SIZE;
 429                                         dp+=4;
 430                                 }
 431                         case TYPE_MC_AAL5:
 432                                 if (header->type == TYPE_MC_AAL5) {
 433                                         packet_len = ntohs(header->wlen);
 434                                         caplen = rlen - dag_record_size - 4;
 435                                         dp+=4;
 436                                 }
 437                                 if (header->type == TYPE_ATM) {
 438                                         caplen = packet_len = ATM_CELL_SIZE;
 439                                 }
 440                                 if (p->linktype == DLT_SUNATM) {
 441                                         struct sunatm_hdr *sunatm = (struct sunatm_hdr *)dp;
 442                                         unsigned long rawatm;
 443
 444                                         rawatm = ntohl(*((unsigned long *)dp));
 445                                         sunatm->vci = htons((rawatm >>  4) & 0xffff);
 446                                         sunatm->vpi = (rawatm >> 20) & 0x00ff;
 447                                         sunatm->flags = ((header->flags.iface & 1) ? 0x80 : 0x00) |
 448                                                 ((sunatm->vpi == 0 && sunatm->vci == htons(5)) ? 6 :
 449                                                  ((sunatm->vpi == 0 && sunatm->vci == htons(16)) ? 5 :
 450                                                   ((dp[ATM_HDR_SIZE] == 0xaa &&
 451                                                     dp[ATM_HDR_SIZE+1] == 0xaa &&
 452                                                     dp[ATM_HDR_SIZE+2] == 0x03) ? 2 : 1)));
 453
 454                                 } else {
 455                                         packet_len -= ATM_HDR_SIZE;
 456                                         caplen -= ATM_HDR_SIZE;
 457                                         dp += ATM_HDR_SIZE;
 458                                 }
 459                                 break;
 460
 461                         case TYPE_COLOR_HASH_ETH:
 462                         case TYPE_DSM_COLOR_ETH:
 463                         case TYPE_COLOR_ETH:
 464                         case TYPE_ETH:
 465                                 packet_len = ntohs(header->wlen);
 466                                 packet_len -= (pd->dag_fcs_bits >> 3);
 467                                 caplen = rlen - dag_record_size - 2;
 468                                 if (caplen > packet_len) {
 469                                         caplen = packet_len;
 470                                 }
 471                                 dp += 2;
 472                                 break;
 473
 474                         case TYPE_COLOR_HASH_POS:
 475                         case TYPE_DSM_COLOR_HDLC_POS:
 476                         case TYPE_COLOR_HDLC_POS:
 477                         case TYPE_HDLC_POS:
 478                                 packet_len = ntohs(header->wlen);
 479                                 packet_len -= (pd->dag_fcs_bits >> 3);
 480                                 caplen = rlen - dag_record_size;
 481                                 if (caplen > packet_len) {
 482                                         caplen = packet_len;
 483                                 }
 484                                 break;
 485
 486                         case TYPE_COLOR_MC_HDLC_POS:
 487                         case TYPE_MC_HDLC:
 488                                 packet_len = ntohs(header->wlen);
 489                                 packet_len -= (pd->dag_fcs_bits >> 3);
 490                                 caplen = rlen - dag_record_size - 4;
 491                                 if (caplen > packet_len) {
 492                                         caplen = packet_len;
 493                                 }
 494                                 /* jump the MC_HDLC_HEADER */
 495                                 dp += 4;
 496 #ifdef DLT_MTP2_WITH_PHDR
 497                                 if (p->linktype == DLT_MTP2_WITH_PHDR) {
 498                                         /* Add the MTP2 Pseudo Header */
 499                                         caplen += MTP2_HDR_LEN;
 500                                         packet_len += MTP2_HDR_LEN;
 501
 502                                         TempPkt[MTP2_SENT_OFFSET] = 0;
 503                                         TempPkt[MTP2_ANNEX_A_USED_OFFSET] = MTP2_ANNEX_A_USED_UNKNOWN;
 504                                         *(TempPkt+MTP2_LINK_NUMBER_OFFSET) = ((header->rec.mc_hdlc.mc_header>>16)&0x01);
 505                                         *(TempPkt+MTP2_LINK_NUMBER_OFFSET+1) = ((header->rec.mc_hdlc.mc_header>>24)&0xff);
 506                                         memcpy(TempPkt+MTP2_HDR_LEN, dp, caplen);
 507                                         dp = TempPkt;
 508                                 }
 509 #endif
 510                                 break;
 511
 512                         case TYPE_IPV4:
 513                         case TYPE_IPV6:
 514                                 packet_len = ntohs(header->wlen);
 515                                 caplen = rlen - dag_record_size;
 516                                 if (caplen > packet_len) {
 517                                         caplen = packet_len;
 518                                 }
 519                                 break;
 520
 521                         /* These types have no matching 'native' DLT, but can be used with DLT_ERF above */
 522                         case TYPE_MC_RAW:
 523                         case TYPE_MC_RAW_CHANNEL:
 524                         case TYPE_IP_COUNTER:
 525                         case TYPE_TCP_FLOW_COUNTER:
 526                         case TYPE_INFINIBAND:
 527                         case TYPE_RAW_LINK:
 528                         case TYPE_INFINIBAND_LINK:
 529                         default:
 530                                 /* Unhandled ERF type.
 531                                  * Ignore rather than generating error
 532                                  */
 533                                 continue;
 534                         } /* switch type */
 535
 536                         /* Skip over extension headers */
 537                         caplen -= (8 * num_ext_hdr);
 538
 539                 } /* ERF encapsulation */
 540
 541                 if (caplen > p->snapshot)
 542                         caplen = p->snapshot;
 543
 544                 /* Run the packet filter if there is one. */
 545                 if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
 546
 547                         /* convert between timestamp formats */
 548                         register unsigned long long ts;
 549
 550                         if (IS_BIGENDIAN()) {
 551                                 ts = SWAPLL(header->ts);
 552                         } else {
 553                                 ts = header->ts;
 554                         }
 555
 556                         pcap_header.ts.tv_sec = ts >> 32;
 557                         ts = (ts & 0xffffffffULL) * 1000000;
 558                         ts += 0x80000000; /* rounding */
 559                         pcap_header.ts.tv_usec = ts >> 32;
 560                         if (pcap_header.ts.tv_usec >= 1000000) {
 561                                 pcap_header.ts.tv_usec -= 1000000;
 562                                 pcap_header.ts.tv_sec++;
 563                         }
 564
 565                         /* Fill in our own header data */
 566                         pcap_header.caplen = caplen;
 567                         pcap_header.len = packet_len;
 568
 569                         /* Count the packet. */
 570                         pd->stat.ps_recv++;
 571
 572                         /* Call the user supplied callback function */
 573                         callback(user, &pcap_header, dp);
 574
 575                         /* Only count packets that pass the filter, for consistency with standard Linux behaviour. */
 576                         processed++;
 577                         if (processed == cnt && !PACKET_COUNT_IS_UNLIMITED(cnt))
 578                         {
 579                                 /* Reached the user-specified limit. */
 580                                 return cnt;
 581                         }
 582                 }
 583         }
 584
 585         return processed;
 586 }
 587
 588 static int
 589 dag_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
 590 {
 591         strlcpy(p->errbuf, "Sending packets isn't supported on DAG cards",
 592             PCAP_ERRBUF_SIZE);
 593         return (-1);
 594 }
 595
 596 /*
 597  *  Get a handle for a live capture from the given DAG device.  Passing a NULL
 598  *  device will result in a failure.  The promisc flag is ignored because DAG
 599  *  cards are always promiscuous.  The to_ms parameter is used in setting the
 600  *  API polling parameters.
 601  *
 602  *  snaplen is now also ignored, until we get per-stream slen support. Set
 603  *  slen with approprite DAG tool BEFORE pcap_activate().
 604  *
 605  *  See also pcap(3).
 606  */
 607 static int dag_activate(pcap_t* handle)
 608 {
 609         struct pcap_dag *handlep = handle->priv;
 610 #if 0
 611         char conf[30]; /* dag configure string */
 612 #endif
 613         char *s;
 614         int n;
 615         daginf_t* daginf;
 616         char * newDev = NULL;
 617         char * device = handle->opt.source;
 618 #ifdef HAVE_DAG_STREAMS_API
 619         uint32_t mindata;
 620         struct timeval maxwait;
 621         struct timeval poll;
 622 #endif
 623
 624         if (device == NULL) {
 625                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "device is NULL: %s", pcap_strerror(errno));
 626                 return -1;
 627         }
 628
 629         /* Initialize some components of the pcap structure. */
 630
 631 #ifdef HAVE_DAG_STREAMS_API
 632         newDev = (char *)malloc(strlen(device) + 16);
 633         if (newDev == NULL) {
 634                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
 635                 goto fail;
 636         }
 637
 638         /* Parse input name to get dag device and stream number if provided */
 639         if (dag_parse_name(device, newDev, strlen(device) + 16, &handlep->dag_stream) < 0) {
 640                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: %s\n", pcap_strerror(errno));
 641                 goto fail;
 642         }
 643         device = newDev;
 644
 645         if (handlep->dag_stream%2) {
 646                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_parse_name: tx (even numbered) streams not supported for capture\n");
 647                 goto fail;
 648         }
 649 #else
 650         if (strncmp(device, "/dev/", 5) != 0) {
 651                 newDev = (char *)malloc(strlen(device) + 5);
 652                 if (newDev == NULL) {
 653                         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate string for device name: %s\n", pcap_strerror(errno));
 654                         goto fail;
 655                 }
 656                 strcpy(newDev, "/dev/");
 657                 strcat(newDev, device);
 658                 device = newDev;
 659         }
 660 #endif /* HAVE_DAG_STREAMS_API */
 661
 662         /* setup device parameters */
 663         if((handle->fd = dag_open((char *)device)) < 0) {
 664                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_open %s: %s", device, pcap_strerror(errno));
 665                 goto fail;
 666         }
 667
 668 #ifdef HAVE_DAG_STREAMS_API
 669         /* Open requested stream. Can fail if already locked or on error */
 670         if (dag_attach_stream(handle->fd, handlep->dag_stream, 0, 0) < 0) {
 671                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_attach_stream: %s\n", pcap_strerror(errno));
 672                 goto failclose;
 673         }
 674
 675         /* Set up default poll parameters for stream
 676          * Can be overridden by pcap_set_nonblock()
 677          */
 678         if (dag_get_stream_poll(handle->fd, handlep->dag_stream,
 679                                 &mindata, &maxwait, &poll) < 0) {
 680                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
 681                 goto faildetach;
 682         }
 683
 684         if (handle->opt.immediate) {
 685                 /* Call callback immediately.
 686                  * XXX - is this the right way to handle this?
 687                  */
 688                 mindata = 0;
 689         } else {
 690                 /* Amount of data to collect in Bytes before calling callbacks.
 691                  * Important for efficiency, but can introduce latency
 692                  * at low packet rates if to_ms not set!
 693                  */
 694                 mindata = 65536;
 695         }
 696
 697         /* Obey opt.timeout (was to_ms) if supplied. This is a good idea!
 698          * Recommend 10-100ms. Calls will time out even if no data arrived.
 699          */
 700         maxwait.tv_sec = handle->opt.timeout/1000;
 701         maxwait.tv_usec = (handle->opt.timeout%1000) * 1000;
 702
 703         if (dag_set_stream_poll(handle->fd, handlep->dag_stream,
 704                                 mindata, &maxwait, &poll) < 0) {
 705                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
 706                 goto faildetach;
 707         }
 708
 709 #else
 710         if((handlep->dag_mem_base = dag_mmap(handle->fd)) == MAP_FAILED) {
 711                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_mmap %s: %s\n", device, pcap_strerror(errno));
 712                 goto failclose;
 713         }
 714
 715 #endif /* HAVE_DAG_STREAMS_API */
 716
 717         /* XXX Not calling dag_configure() to set slen; this is unsafe in
 718          * multi-stream environments as the gpp config is global.
 719          * Once the firmware provides 'per-stream slen' this can be supported
 720          * again via the Config API without side-effects */
 721 #if 0
 722         /* set the card snap length to the specified snaplen parameter */
 723         /* This is a really bad idea, as different cards have different
 724          * valid slen ranges. Should fix in Config API. */
 725         if (handle->snapshot == 0 || handle->snapshot > MAX_DAG_SNAPLEN) {
 726                 handle->snapshot = MAX_DAG_SNAPLEN;
 727         } else if (snaplen < MIN_DAG_SNAPLEN) {
 728                 handle->snapshot = MIN_DAG_SNAPLEN;
 729         }
 730         /* snap len has to be a multiple of 4 */
 731         snprintf(conf, 30, "varlen slen=%d", (snaplen + 3) & ~3);
 732
 733         if(dag_configure(handle->fd, conf) < 0) {
 734                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,"dag_configure %s: %s\n", device, pcap_strerror(errno));
 735                 goto faildetach;
 736         }
 737 #endif
 738
 739 #ifdef HAVE_DAG_STREAMS_API
 740         if(dag_start_stream(handle->fd, handlep->dag_stream) < 0) {
 741                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start_stream %s: %s\n", device, pcap_strerror(errno));
 742                 goto faildetach;
 743         }
 744 #else
 745         if(dag_start(handle->fd) < 0) {
 746                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dag_start %s: %s\n", device, pcap_strerror(errno));
 747                 goto failclose;
 748         }
 749 #endif /* HAVE_DAG_STREAMS_API */
 750
 751         /*
 752          * Important! You have to ensure bottom is properly
 753          * initialized to zero on startup, it won't give you
 754          * a compiler warning if you make this mistake!
 755          */
 756         handlep->dag_mem_bottom = 0;
 757         handlep->dag_mem_top = 0;
 758
 759         /*
 760          * Find out how many FCS bits we should strip.
 761          * First, query the card to see if it strips the FCS.
 762          */
 763         daginf = dag_info(handle->fd);
 764         if ((0x4200 == daginf->device_code) || (0x4230 == daginf->device_code)) {
 765                 /* DAG 4.2S and 4.23S already strip the FCS.  Stripping the final word again truncates the packet. */
 766                 handlep->dag_fcs_bits = 0;
 767
 768                 /* Note that no FCS will be supplied. */
 769                 handle->linktype_ext = LT_FCS_DATALINK_EXT(0);
 770         } else {
 771                 /*
 772                  * Start out assuming it's 32 bits.
 773                  */
 774                 handlep->dag_fcs_bits = 32;
 775
 776                 /* Allow an environment variable to override. */
 777                 if ((s = getenv("ERF_FCS_BITS")) != NULL) {
 778                         if ((n = atoi(s)) == 0 || n == 16 || n == 32) {
 779                                 handlep->dag_fcs_bits = n;
 780                         } else {
 781                                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 782                                         "pcap_activate %s: bad ERF_FCS_BITS value (%d) in environment\n", device, n);
 783                                 goto failstop;
 784                         }
 785                 }
 786
 787                 /*
 788                  * Did the user request that they not be stripped?
 789                  */
 790                 if ((s = getenv("ERF_DONT_STRIP_FCS")) != NULL) {
 791                         /* Yes.  Note the number of bytes that will be
 792                            supplied. */
 793                         handle->linktype_ext = LT_FCS_DATALINK_EXT(handlep->dag_fcs_bits/16);
 794
 795                         /* And don't strip them. */
 796                         handlep->dag_fcs_bits = 0;
 797                 }
 798         }
 799
 800         handlep->dag_timeout    = handle->opt.timeout;
 801
 802         handle->linktype = -1;
 803         if (dag_get_datalink(handle) < 0)
 804                 goto failstop;
 805
 806         handle->bufsize = 0;
 807
 808         if (new_pcap_dag(handle) < 0) {
 809                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "new_pcap_dag %s: %s\n", device, pcap_strerror(errno));
 810                 goto failstop;
 811         }
 812
 813         /*
 814          * "select()" and "poll()" don't work on DAG device descriptors.
 815          */
 816         handle->selectable_fd = -1;
 817
 818         if (newDev != NULL) {
 819                 free((char *)newDev);
 820         }
 821
 822         handle->read_op = dag_read;
 823         handle->inject_op = dag_inject;
 824         handle->setfilter_op = dag_setfilter;
 825         handle->setdirection_op = NULL; /* Not implemented.*/
 826         handle->set_datalink_op = dag_set_datalink;
 827         handle->getnonblock_op = pcap_getnonblock_fd;
 828         handle->setnonblock_op = dag_setnonblock;
 829         handle->stats_op = dag_stats;
 830         handle->cleanup_op = dag_platform_cleanup;
 831         handlep->stat.ps_drop = 0;
 832         handlep->stat.ps_recv = 0;
 833         handlep->stat.ps_ifdrop = 0;
 834         return 0;
 835
 836 #ifdef HAVE_DAG_STREAMS_API
 837 failstop:
 838         if (dag_stop_stream(handle->fd, handlep->dag_stream) < 0) {
 839                 fprintf(stderr,"dag_stop_stream: %s\n", strerror(errno));
 840         }
 841
 842 faildetach:
 843         if (dag_detach_stream(handle->fd, handlep->dag_stream) < 0)
 844                 fprintf(stderr,"dag_detach_stream: %s\n", strerror(errno));
 845 #else
 846 failstop:
 847         if (dag_stop(handle->fd) < 0)
 848                 fprintf(stderr,"dag_stop: %s\n", strerror(errno));
 849 #endif /* HAVE_DAG_STREAMS_API */
 850
 851 failclose:
 852         if (dag_close(handle->fd) < 0)
 853                 fprintf(stderr,"dag_close: %s\n", strerror(errno));
 854         delete_pcap_dag(handle);
 855
 856 fail:
 857         pcap_cleanup_live_common(handle);
 858         if (newDev != NULL) {
 859                 free((char *)newDev);
 860         }
 861
 862         return PCAP_ERROR;
 863 }
 864
 865 pcap_t *dag_create(const char *device, char *ebuf, int *is_ours)
 866 {
 867         const char *cp;
 868         char *cpend;
 869         long devnum;
 870         pcap_t *p;
 871 #ifdef HAVE_DAG_STREAMS_API
 872         long stream = 0;
 873 #endif
 874
 875         /* Does this look like a DAG device? */
 876         cp = strrchr(device, '/');
 877         if (cp == NULL)
 878                 cp = device;
 879         /* Does it begin with "dag"? */
 880         if (strncmp(cp, "dag", 3) != 0) {
 881                 /* Nope, doesn't begin with "dag" */
 882                 *is_ours = 0;
 883                 return NULL;
 884         }
 885         /* Yes - is "dag" followed by a number from 0 to DAG_MAX_BOARDS-1 */
 886         cp += 3;
 887         devnum = strtol(cp, &cpend, 10);
 888 #ifdef HAVE_DAG_STREAMS_API
 889         if (*cpend == ':') {
 890                 /* Followed by a stream number. */
 891                 stream = strtol(++cpend, &cpend, 10);
 892         }
 893 #endif
 894         if (cpend == cp || *cpend != '\0') {
 895                 /* Not followed by a number. */
 896                 *is_ours = 0;
 897                 return NULL;
 898         }
 899         if (devnum < 0 || devnum >= DAG_MAX_BOARDS) {
 900                 /* Followed by a non-valid number. */
 901                 *is_ours = 0;
 902                 return NULL;
 903         }
 904 #ifdef HAVE_DAG_STREAMS_API
 905         if (stream <0 || stream >= DAG_STREAM_MAX) {
 906                 /* Followed by a non-valid stream number. */
 907                 *is_ours = 0;
 908                 return NULL;
 909         }
 910 #endif
 911
 912         /* OK, it's probably ours. */
 913         *is_ours = 1;
 914
 915         p = pcap_create_common(device, ebuf, sizeof (struct pcap_dag));
 916         if (p == NULL)
 917                 return NULL;
 918
 919         p->activate_op = dag_activate;
 920         return p;
 921 }
 922
 923 static int
 924 dag_stats(pcap_t *p, struct pcap_stat *ps) {
 925         struct pcap_dag *pd = p->priv;
 926
 927         /* This needs to be filled out correctly.  Hopefully a dagapi call will
 928                  provide all necessary information.
 929         */
 930         /*pd->stat.ps_recv = 0;*/
 931         /*pd->stat.ps_drop = 0;*/
 932
 933         *ps = pd->stat;
 934
 935         return 0;
 936 }
 937
 938 /*
 939  * Previously we just generated a list of all possible names and let
 940  * pcap_add_if() attempt to open each one, but with streams this adds up
 941  * to 81 possibilities which is inefficient.
 942  *
 943  * Since we know more about the devices we can prune the tree here.
 944  * pcap_add_if() will still retest each device but the total number of
 945  * open attempts will still be much less than the naive approach.
 946  */
 947 int
 948 dag_findalldevs(pcap_if_t **devlistp, char *errbuf)
 949 {
 950         char name[12];  /* XXX - pick a size */
 951         int ret = 0;
 952         int c;
 953         char dagname[DAGNAME_BUFSIZE];
 954         int dagstream;
 955         int dagfd;
 956
 957         /* Try all the DAGs 0-DAG_MAX_BOARDS */
 958         for (c = 0; c < DAG_MAX_BOARDS; c++) {
 959                 snprintf(name, 12, "dag%d", c);
 960                 if (-1 == dag_parse_name(name, dagname, DAGNAME_BUFSIZE, &dagstream))
 961                 {
 962                         return -1;
 963                 }
 964                 if ( (dagfd = dag_open(dagname)) >= 0 ) {
 965                         if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
 966                                 /*
 967                                  * Failure.
 968                                  */
 969                                 ret = -1;
 970                         }
 971 #ifdef HAVE_DAG_STREAMS_API
 972                         {
 973                                 int stream, rxstreams;
 974                                 rxstreams = dag_rx_get_stream_count(dagfd);
 975                                 for(stream=0;stream<DAG_STREAM_MAX;stream+=2) {
 976                                         if (0 == dag_attach_stream(dagfd, stream, 0, 0)) {
 977                                                 dag_detach_stream(dagfd, stream);
 978
 979                                                 snprintf(name,  10, "dag%d:%d", c, stream);
 980                                                 if (pcap_add_if(devlistp, name, 0, NULL, errbuf) == -1) {
 981                                                         /*
 982                                                          * Failure.
 983                                                          */
 984                                                         ret = -1;
 985                                                 }
 986
 987                                                 rxstreams--;
 988                                                 if(rxstreams <= 0) {
 989                                                         break;
 990                                                 }
 991                                         }
 992                                 }
 993                         }
 994 #endif  /* HAVE_DAG_STREAMS_API */
 995                         dag_close(dagfd);
 996                 }
 997
 998         }
 999         return (ret);
1000 }
1001
1002 /*
1003  * Installs the given bpf filter program in the given pcap structure.  There is
1004  * no attempt to store the filter in kernel memory as that is not supported
1005  * with DAG cards.
1006  */
1007 static int
1008 dag_setfilter(pcap_t *p, struct bpf_program *fp)
1009 {
1010         if (!p)
1011                 return -1;
1012         if (!fp) {
1013                 strncpy(p->errbuf, "setfilter: No filter specified",
1014                         sizeof(p->errbuf));
1015                 return -1;
1016         }
1017
1018         /* Make our private copy of the filter */
1019
1020         if (install_bpf_program(p, fp) < 0)
1021                 return -1;
1022
1023         return (0);
1024 }
1025
1026 static int
1027 dag_set_datalink(pcap_t *p, int dlt)
1028 {
1029         p->linktype = dlt;
1030
1031         return (0);
1032 }
1033
1034 static int
1035 dag_setnonblock(pcap_t *p, int nonblock, char *errbuf)
1036 {
1037         struct pcap_dag *pd = p->priv;
1038
1039         /*
1040          * Set non-blocking mode on the FD.
1041          * XXX - is that necessary?  If not, don't bother calling it,
1042          * and have a "dag_getnonblock()" function that looks at
1043          * "pd->dag_offset_flags".
1044          */
1045         if (pcap_setnonblock_fd(p, nonblock, errbuf) < 0)
1046                 return (-1);
1047 #ifdef HAVE_DAG_STREAMS_API
1048         {
1049                 uint32_t mindata;
1050                 struct timeval maxwait;
1051                 struct timeval poll;
1052
1053                 if (dag_get_stream_poll(p->fd, pd->dag_stream,
1054                                         &mindata, &maxwait, &poll) < 0) {
1055                         snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_get_stream_poll: %s\n", pcap_strerror(errno));
1056                         return -1;
1057                 }
1058
1059                 /* Amount of data to collect in Bytes before calling callbacks.
1060                  * Important for efficiency, but can introduce latency
1061                  * at low packet rates if to_ms not set!
1062                  */
1063                 if(nonblock)
1064                         mindata = 0;
1065                 else
1066                         mindata = 65536;
1067
1068                 if (dag_set_stream_poll(p->fd, pd->dag_stream,
1069                                         mindata, &maxwait, &poll) < 0) {
1070                         snprintf(errbuf, PCAP_ERRBUF_SIZE, "dag_set_stream_poll: %s\n", pcap_strerror(errno));
1071                         return -1;
1072                 }
1073         }
1074 #endif /* HAVE_DAG_STREAMS_API */
1075         if (nonblock) {
1076                 pd->dag_offset_flags |= DAGF_NONBLOCK;
1077         } else {
1078                 pd->dag_offset_flags &= ~DAGF_NONBLOCK;
1079         }
1080         return (0);
1081 }
1082
1083 static int
1084 dag_get_datalink(pcap_t *p)
1085 {
1086         struct pcap_dag *pd = p->priv;
1087         int index=0, dlt_index=0;
1088         uint8_t types[255];
1089
1090         memset(types, 0, 255);
1091
1092         if (p->dlt_list == NULL && (p->dlt_list = malloc(255*sizeof(*(p->dlt_list)))) == NULL) {
1093                 (void)snprintf(p->errbuf, sizeof(p->errbuf), "malloc: %s", pcap_strerror(errno));
1094                 return (-1);
1095         }
1096
1097         p->linktype = 0;
1098
1099 #ifdef HAVE_DAG_GET_STREAM_ERF_TYPES
1100         /* Get list of possible ERF types for this card */
1101         if (dag_get_stream_erf_types(p->fd, pd->dag_stream, types, 255) < 0) {
1102                 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_stream_erf_types: %s", pcap_strerror(errno));
1103                 return (-1);
1104         }
1105
1106         while (types[index]) {
1107
1108 #elif defined HAVE_DAG_GET_ERF_TYPES
1109         /* Get list of possible ERF types for this card */
1110         if (dag_get_erf_types(p->fd, types, 255) < 0) {
1111                 snprintf(p->errbuf, sizeof(p->errbuf), "dag_get_erf_types: %s", pcap_strerror(errno));
1112                 return (-1);
1113         }
1114
1115         while (types[index]) {
1116 #else
1117         /* Check the type through a dagapi call. */
1118         types[index] = dag_linktype(p->fd);
1119
1120         {
1121 #endif
1122                 switch((types[index] & 0x7f)) {
1123
1124                 case TYPE_HDLC_POS:
1125                 case TYPE_COLOR_HDLC_POS:
1126                 case TYPE_DSM_COLOR_HDLC_POS:
1127                 case TYPE_COLOR_HASH_POS:
1128
1129                         if (p->dlt_list != NULL) {
1130                                 p->dlt_list[dlt_index++] = DLT_CHDLC;
1131                                 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1132                                 p->dlt_list[dlt_index++] = DLT_FRELAY;
1133                         }
1134                         if(!p->linktype)
1135                                 p->linktype = DLT_CHDLC;
1136                         break;
1137
1138                 case TYPE_ETH:
1139                 case TYPE_COLOR_ETH:
1140                 case TYPE_DSM_COLOR_ETH:
1141                 case TYPE_COLOR_HASH_ETH:
1142                         /*
1143                          * This is (presumably) a real Ethernet capture; give it a
1144                          * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
1145                          * that an application can let you choose it, in case you're
1146                          * capturing DOCSIS traffic that a Cisco Cable Modem
1147                          * Termination System is putting out onto an Ethernet (it
1148                          * doesn't put an Ethernet header onto the wire, it puts raw
1149                          * DOCSIS frames out on the wire inside the low-level
1150                          * Ethernet framing).
1151                          */
1152                         if (p->dlt_list != NULL) {
1153                                 p->dlt_list[dlt_index++] = DLT_EN10MB;
1154                                 p->dlt_list[dlt_index++] = DLT_DOCSIS;
1155                         }
1156                         if(!p->linktype)
1157                                 p->linktype = DLT_EN10MB;
1158                         break;
1159
1160                 case TYPE_ATM:
1161                 case TYPE_AAL5:
1162                 case TYPE_MC_ATM:
1163                 case TYPE_MC_AAL5:
1164                         if (p->dlt_list != NULL) {
1165                                 p->dlt_list[dlt_index++] = DLT_ATM_RFC1483;
1166                                 p->dlt_list[dlt_index++] = DLT_SUNATM;
1167                         }
1168                         if(!p->linktype)
1169                                 p->linktype = DLT_ATM_RFC1483;
1170                         break;
1171
1172                 case TYPE_COLOR_MC_HDLC_POS:
1173                 case TYPE_MC_HDLC:
1174                         if (p->dlt_list != NULL) {
1175                                 p->dlt_list[dlt_index++] = DLT_CHDLC;
1176                                 p->dlt_list[dlt_index++] = DLT_PPP_SERIAL;
1177                                 p->dlt_list[dlt_index++] = DLT_FRELAY;
1178                                 p->dlt_list[dlt_index++] = DLT_MTP2;
1179                                 p->dlt_list[dlt_index++] = DLT_MTP2_WITH_PHDR;
1180                                 p->dlt_list[dlt_index++] = DLT_LAPD;
1181                         }
1182                         if(!p->linktype)
1183                                 p->linktype = DLT_CHDLC;
1184                         break;
1185
1186                 case TYPE_IPV4:
1187                 case TYPE_IPV6:
1188                         if(!p->linktype)
1189                                 p->linktype = DLT_RAW;
1190                         break;
1191
1192                 case TYPE_LEGACY:
1193                 case TYPE_MC_RAW:
1194                 case TYPE_MC_RAW_CHANNEL:
1195                 case TYPE_IP_COUNTER:
1196                 case TYPE_TCP_FLOW_COUNTER:
1197                 case TYPE_INFINIBAND:
1198                 case TYPE_RAW_LINK:
1199                 case TYPE_INFINIBAND_LINK:
1200                 default:
1201                         /* Libpcap cannot deal with these types yet */
1202                         /* Add no 'native' DLTs, but still covered by DLT_ERF */
1203                         break;
1204
1205                 } /* switch */
1206                 index++;
1207         }
1208
1209         p->dlt_list[dlt_index++] = DLT_ERF;
1210
1211         p->dlt_count = dlt_index;
1212
1213         if(!p->linktype)
1214                 p->linktype = DLT_ERF;
1215
1216         return p->linktype;
1217 }