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

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4
   5 #ifndef _WIN32
   6 #include <sys/param.h>
   7 #endif /* !_WIN32 */
   8
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <errno.h>
  12 #include <limits.h> /* for INT_MAX */
  13
  14 #ifndef _WIN32
  15 #include <netinet/in.h>
  16 #include <sys/mman.h>
  17 #include <sys/socket.h>
  18 #include <sys/types.h>
  19 #include <unistd.h>
  20 #endif /* !_WIN32 */
  21
  22 #include <snf.h>
  23 #if SNF_VERSION_API >= 0x0003
  24 #define SNF_HAVE_INJECT_API
  25 #endif
  26
  27 #include "pcap-int.h"
  28 #include "pcap-snf.h"
  29
  30 /*
  31  * Private data for capturing on SNF devices.
  32  */
  33 struct pcap_snf {
  34         snf_handle_t snf_handle; /* opaque device handle */
  35         snf_ring_t   snf_ring;   /* opaque device ring handle */
  36 #ifdef SNF_HAVE_INJECT_API
  37         snf_inject_t snf_inj;    /* inject handle, if inject is used */
  38 #endif
  39         int          snf_timeout;
  40         int          snf_boardnum;
  41 };
  42
  43 static int
  44 snf_set_datalink(pcap_t *p, int dlt)
  45 {
  46         p->linktype = dlt;
  47         return (0);
  48 }
  49
  50 static int
  51 snf_pcap_stats(pcap_t *p, struct pcap_stat *ps)
  52 {
  53         struct snf_ring_stats stats;
  54         struct pcap_snf *snfps = p->priv;
  55         int rc;
  56
  57         if ((rc = snf_ring_getstats(snfps->snf_ring, &stats))) {
  58                 pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
  59                     rc, "snf_get_stats");
  60                 return -1;
  61         }
  62         ps->ps_recv = stats.ring_pkt_recv + stats.ring_pkt_overflow;
  63         ps->ps_drop = stats.ring_pkt_overflow;
  64         ps->ps_ifdrop = stats.nic_pkt_overflow + stats.nic_pkt_bad;
  65         return 0;
  66 }
  67
  68 static void
  69 snf_platform_cleanup(pcap_t *p)
  70 {
  71         struct pcap_snf *ps = p->priv;
  72
  73 #ifdef SNF_HAVE_INJECT_API
  74         if (ps->snf_inj)
  75                 snf_inject_close(ps->snf_inj);
  76 #endif
  77         snf_ring_close(ps->snf_ring);
  78         snf_close(ps->snf_handle);
  79         pcap_cleanup_live_common(p);
  80 }
  81
  82 static int
  83 snf_getnonblock(pcap_t *p)
  84 {
  85         struct pcap_snf *ps = p->priv;
  86
  87         return (ps->snf_timeout == 0);
  88 }
  89
  90 static int
  91 snf_setnonblock(pcap_t *p, int nonblock)
  92 {
  93         struct pcap_snf *ps = p->priv;
  94
  95         if (nonblock)
  96                 ps->snf_timeout = 0;
  97         else {
  98                 if (p->opt.timeout <= 0)
  99                         ps->snf_timeout = -1; /* forever */
 100                 else
 101                         ps->snf_timeout = p->opt.timeout;
 102         }
 103         return (0);
 104 }
 105
 106 #define _NSEC_PER_SEC 1000000000
 107
 108 static inline
 109 struct timeval
 110 snf_timestamp_to_timeval(const int64_t ts_nanosec, const int tstamp_precision)
 111 {
 112         struct timeval tv;
 113         long tv_nsec;
 114         const static struct timeval zero_timeval;
 115
 116         if (ts_nanosec == 0)
 117                 return zero_timeval;
 118
 119         tv.tv_sec = ts_nanosec / _NSEC_PER_SEC;
 120         tv_nsec = (ts_nanosec % _NSEC_PER_SEC);
 121
 122         /* libpcap expects tv_usec to be nanos if using nanosecond precision. */
 123         if (tstamp_precision == PCAP_TSTAMP_PRECISION_NANO)
 124                 tv.tv_usec = tv_nsec;
 125         else
 126                 tv.tv_usec = tv_nsec / 1000;
 127
 128         return tv;
 129 }
 130
 131 static int
 132 snf_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
 133 {
 134         struct pcap_snf *ps = p->priv;
 135         struct pcap_pkthdr hdr;
 136         int i, flags, err, caplen, n;
 137         struct snf_recv_req req;
 138         int nonblock, timeout;
 139
 140         if (!p)
 141                 return -1;
 142
 143         /*
 144          * This can conceivably process more than INT_MAX packets,
 145          * which would overflow the packet count, causing it either
 146          * to look like a negative number, and thus cause us to
 147          * return a value that looks like an error, or overflow
 148          * back into positive territory, and thus cause us to
 149          * return a too-low count.
 150          *
 151          * Therefore, if the packet count is unlimited, we clip
 152          * it at INT_MAX; this routine is not expected to
 153          * process packets indefinitely, so that's not an issue.
 154          */
 155         if (PACKET_COUNT_IS_UNLIMITED(cnt))
 156                 cnt = INT_MAX;
 157
 158         n = 0;
 159         timeout = ps->snf_timeout;
 160         while (n < cnt) {
 161                 /*
 162                  * Has "pcap_breakloop()" been called?
 163                  */
 164                 if (p->break_loop) {
 165                         if (n == 0) {
 166                                 p->break_loop = 0;
 167                                 return (-2);
 168                         } else {
 169                                 return (n);
 170                         }
 171                 }
 172
 173                 err = snf_ring_recv(ps->snf_ring, timeout, &req);
 174
 175                 if (err) {
 176                         if (err == EBUSY || err == EAGAIN) {
 177                                 return (n);
 178                         }
 179                         else if (err == EINTR) {
 180                                 timeout = 0;
 181                                 continue;
 182                         }
 183                         else {
 184                                 pcap_fmt_errmsg_for_errno(p->errbuf,
 185                                     PCAP_ERRBUF_SIZE, err, "snf_read");
 186                                 return -1;
 187                         }
 188                 }
 189
 190                 caplen = req.length;
 191                 if (caplen > p->snapshot)
 192                         caplen = p->snapshot;
 193
 194                 if ((p->fcode.bf_insns == NULL) ||
 195                      pcap_filter(p->fcode.bf_insns, req.pkt_addr, req.length, caplen)) {
 196                         hdr.ts = snf_timestamp_to_timeval(req.timestamp, p->opt.tstamp_precision);
 197                         hdr.caplen = caplen;
 198                         hdr.len = req.length;
 199                         callback(user, &hdr, req.pkt_addr);
 200                         n++;
 201                 }
 202
 203                 /* After one successful packet is received, we won't block
 204                 * again for that timeout. */
 205                 if (timeout != 0)
 206                         timeout = 0;
 207         }
 208         return (n);
 209 }
 210
 211 static int
 212 snf_inject(pcap_t *p, const void *buf _U_, int size _U_)
 213 {
 214 #ifdef SNF_HAVE_INJECT_API
 215         struct pcap_snf *ps = p->priv;
 216         int rc;
 217         if (ps->snf_inj == NULL) {
 218                 rc = snf_inject_open(ps->snf_boardnum, 0, &ps->snf_inj);
 219                 if (rc) {
 220                         pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
 221                             rc, "snf_inject_open");
 222                         return (-1);
 223                 }
 224         }
 225
 226         rc = snf_inject_send(ps->snf_inj, -1, 0, buf, size);
 227         if (!rc) {
 228                 return (size);
 229         }
 230         else {
 231                 pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
 232                     rc, "snf_inject_send");
 233                 return (-1);
 234         }
 235 #else
 236         pcap_strlcpy(p->errbuf, "Sending packets isn't supported with this snf version",
 237             PCAP_ERRBUF_SIZE);
 238         return (-1);
 239 #endif
 240 }
 241
 242 static int
 243 snf_activate(pcap_t* p)
 244 {
 245         struct pcap_snf *ps = p->priv;
 246         char *device = p->opt.device;
 247         const char *nr = NULL;
 248         int err;
 249         int flags = -1, ring_id = -1;
 250
 251         if (device == NULL) {
 252                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "device is NULL");
 253                 return -1;
 254         }
 255
 256         /* In Libpcap, we set pshared by default if NUM_RINGS is set to > 1.
 257          * Since libpcap isn't thread-safe */
 258         if ((nr = getenv("SNF_FLAGS")) && *nr)
 259                 flags = strtol(nr, NULL, 0);
 260         else if ((nr = getenv("SNF_NUM_RINGS")) && *nr && atoi(nr) > 1)
 261                 flags = SNF_F_PSHARED;
 262         else
 263                 nr = NULL;
 264
 265
 266         /* Allow pcap_set_buffer_size() to set dataring_size.
 267          * Default is zero which allows setting from env SNF_DATARING_SIZE.
 268          * pcap_set_buffer_size() is in bytes while snf_open() accepts values
 269          * between 0 and 1048576 in Megabytes. Values in this range are
 270          * mapped to 1MB.
 271          */
 272         err = snf_open(ps->snf_boardnum,
 273                         0, /* let SNF API parse SNF_NUM_RINGS, if set */
 274                         NULL, /* default RSS, or use SNF_RSS_FLAGS env */
 275                         (p->opt.buffer_size > 0 && p->opt.buffer_size < 1048576) ? 1048576 : p->opt.buffer_size, /* default to SNF_DATARING_SIZE from env */
 276                         flags, /* may want pshared */
 277                         &ps->snf_handle);
 278         if (err != 0) {
 279                 pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
 280                     err, "snf_open failed");
 281                 return -1;
 282         }
 283
 284         if ((nr = getenv("SNF_PCAP_RING_ID")) && *nr) {
 285                 ring_id = (int) strtol(nr, NULL, 0);
 286         }
 287         err = snf_ring_open_id(ps->snf_handle, ring_id, &ps->snf_ring);
 288         if (err != 0) {
 289                 pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
 290                     err, "snf_ring_open_id(ring=%d) failed", ring_id);
 291                 return -1;
 292         }
 293
 294         /*
 295          * Turn a negative snapshot value (invalid), a snapshot value of
 296          * 0 (unspecified), or a value bigger than the normal maximum
 297          * value, into the maximum allowed value.
 298          *
 299          * If some application really *needs* a bigger snapshot
 300          * length, we should just increase MAXIMUM_SNAPLEN.
 301          */
 302         if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
 303                 p->snapshot = MAXIMUM_SNAPLEN;
 304
 305         if (p->opt.timeout <= 0)
 306                 ps->snf_timeout = -1;
 307         else
 308                 ps->snf_timeout = p->opt.timeout;
 309
 310         err = snf_start(ps->snf_handle);
 311         if (err != 0) {
 312                 pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
 313                     err, "snf_start failed");
 314                 return -1;
 315         }
 316
 317         /*
 318          * "select()" and "poll()" don't work on snf descriptors.
 319          */
 320 #ifndef _WIN32
 321         p->selectable_fd = -1;
 322 #endif /* !_WIN32 */
 323         p->linktype = DLT_EN10MB;
 324         p->read_op = snf_read;
 325         p->inject_op = snf_inject;
 326         p->setfilter_op = install_bpf_program;
 327         p->setdirection_op = NULL; /* Not implemented.*/
 328         p->set_datalink_op = snf_set_datalink;
 329         p->getnonblock_op = snf_getnonblock;
 330         p->setnonblock_op = snf_setnonblock;
 331         p->stats_op = snf_pcap_stats;
 332         p->cleanup_op = snf_platform_cleanup;
 333 #ifdef SNF_HAVE_INJECT_API
 334         ps->snf_inj = NULL;
 335 #endif
 336         return 0;
 337 }
 338
 339 #define MAX_DESC_LENGTH 128
 340 int
 341 snf_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
 342 {
 343         pcap_if_t *dev;
 344 #ifdef _WIN32
 345         struct sockaddr_in addr;
 346 #endif
 347         struct snf_ifaddrs *ifaddrs, *ifa;
 348         char name[MAX_DESC_LENGTH];
 349         char desc[MAX_DESC_LENGTH];
 350         int ret, allports = 0, merge = 0;
 351         const char *nr = NULL;
 352
 353         if (snf_init(SNF_VERSION_API)) {
 354                 (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 355                     "snf_getifaddrs: snf_init failed");
 356                 return (-1);
 357         }
 358
 359         if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL)
 360         {
 361                 pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
 362                     errno, "snf_getifaddrs");
 363                 return (-1);
 364         }
 365         if ((nr = getenv("SNF_FLAGS")) && *nr) {
 366                 errno = 0;
 367                 merge = strtol(nr, NULL, 0);
 368                 if (errno) {
 369                         (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 370                                 "snf_getifaddrs: SNF_FLAGS is not a valid number");
 371                         return (-1);
 372                 }
 373                 merge = merge & SNF_F_AGGREGATE_PORTMASK;
 374         }
 375
 376         for (ifa = ifaddrs; ifa != NULL; ifa = ifa->snf_ifa_next) {
 377                 /*
 378                  * Myricom SNF adapter ports may appear as regular
 379                  * network interfaces, which would already have been
 380                  * added to the list of adapters by pcap_platform_finddevs()
 381                  * if this isn't an SNF-only version of libpcap.
 382                  *
 383                  * Our create routine intercepts pcap_create() calls for
 384                  * those interfaces and arranges that they will be
 385                  * opened using the SNF API instead.
 386                  *
 387                  * So if we already have an entry for the device, we
 388                  * don't add an additional entry for it, we just
 389                  * update the description for it, if any, to indicate
 390                  * which snfN device it is.  Otherwise, we add an entry
 391                  * for it.
 392                  *
 393                  * In either case, if SNF_F_AGGREGATE_PORTMASK is set
 394                  * in SNF_FLAGS, we add this port to the bitmask
 395                  * of ports, which we use to generate a device
 396                  * we can use to capture on all ports.
 397                  *
 398                  * Generate the description string.  If port aggregation
 399                  * is set, use 2^{port number} as the unit number,
 400                  * rather than {port number}.
 401                  *
 402                  * XXX - do entries in this list have IP addresses for
 403                  * the port?  If so, should we add them to the
 404                  * entry for the device, if they're not already in the
 405                  * list of IP addresses for the device?
 406                  */
 407                 (void)snprintf(desc,MAX_DESC_LENGTH,"Myricom %ssnf%d",
 408                         merge ? "Merge Bitmask Port " : "",
 409                         merge ? 1 << ifa->snf_ifa_portnum : ifa->snf_ifa_portnum);
 410                 /*
 411                  * Add the port to the bitmask.
 412                  */
 413                 if (merge)
 414                         allports |= 1 << ifa->snf_ifa_portnum;
 415                 /*
 416                  * See if there's already an entry for the device
 417                  * with the name ifa->snf_ifa_name.
 418                  */
 419                 dev = find_dev(devlistp, ifa->snf_ifa_name);
 420                 if (dev != NULL) {
 421                         /*
 422                          * Yes.  Update its description.
 423                          */
 424                         char *desc_str;
 425
 426                         desc_str = strdup(desc);
 427                         if (desc_str == NULL) {
 428                                 pcap_fmt_errmsg_for_errno(errbuf,
 429                                     PCAP_ERRBUF_SIZE, errno,
 430                                     "snf_findalldevs strdup");
 431                                 return -1;
 432                         }
 433                         free(dev->description);
 434                         dev->description = desc_str;
 435                 } else {
 436                         /*
 437                          * No.  Add an entry for it.
 438                          *
 439                          * XXX - is there a notion of "up" or "running",
 440                          * and can we determine whether something's
 441                          * plugged into the adapter and set
 442                          * PCAP_IF_CONNECTION_STATUS_CONNECTED or
 443                          * PCAP_IF_CONNECTION_STATUS_DISCONNECTED?
 444                          */
 445                         dev = add_dev(devlistp, ifa->snf_ifa_name, 0, desc,
 446                             errbuf);
 447                         if (dev == NULL)
 448                                 return -1;
 449 #ifdef _WIN32
 450                         /*
 451                          * On Windows, fill in IP# from device name
 452                          */
 453                         ret = inet_pton(AF_INET, dev->name, &addr.sin_addr);
 454                         if (ret == 1) {
 455                                 /*
 456                                  * Successful conversion of device name
 457                                  * to IPv4 address.
 458                                  */
 459                                 addr.sin_family = AF_INET;
 460                                 if (add_addr_to_dev(dev, &addr, sizeof(addr),
 461                                     NULL, 0, NULL, 0, NULL, 0, errbuf) == -1)
 462                                         return -1;
 463                         } else if (ret == -1) {
 464                                 /*
 465                                  * Error.
 466                                  */
 467                                 pcap_fmt_errmsg_for_errno(errbuf,
 468                                     PCAP_ERRBUF_SIZE, errno,
 469                                     "sinf_findalldevs inet_pton");
 470                                 return -1;
 471                         }
 472 #endif _WIN32
 473                 }
 474         }
 475         snf_freeifaddrs(ifaddrs);
 476         /*
 477          * Create a snfX entry if port aggregation is enabled
 478          */
 479         if (merge) {
 480                 /*
 481                  * Add a new entry with all ports bitmask
 482                  */
 483                 (void)snprintf(name,MAX_DESC_LENGTH,"snf%d",allports);
 484                 (void)snprintf(desc,MAX_DESC_LENGTH,"Myricom Merge Bitmask All Ports snf%d",
 485                         allports);
 486                 /*
 487                  * XXX - is there any notion of "up" and "running" that
 488                  * would apply to this device, given that it handles
 489                  * multiple ports?
 490                  *
 491                  * Presumably, there's no notion of "connected" vs.
 492                  * "disconnected", as "is this plugged into a network?"
 493                  * would be a per-port property.
 494                  */
 495                 if (add_dev(devlistp, name,
 496                     PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE, desc,
 497                     errbuf) == NULL)
 498                         return (-1);
 499                 /*
 500                  * XXX - should we give it a list of addresses with all
 501                  * the addresses for all the ports?
 502                  */
 503         }
 504
 505         return 0;
 506 }
 507
 508 pcap_t *
 509 snf_create(const char *device, char *ebuf, int *is_ours)
 510 {
 511         pcap_t *p;
 512         int boardnum = -1;
 513         struct snf_ifaddrs *ifaddrs, *ifa;
 514         size_t devlen;
 515         struct pcap_snf *ps;
 516
 517         if (snf_init(SNF_VERSION_API)) {
 518                 /* Can't initialize the API, so no SNF devices */
 519                 *is_ours = 0;
 520                 return NULL;
 521         }
 522
 523         /*
 524          * Match a given interface name to our list of interface names, from
 525          * which we can obtain the intended board number
 526          */
 527         if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL) {
 528                 /* Can't get SNF addresses */
 529                 *is_ours = 0;
 530                 return NULL;
 531         }
 532         devlen = strlen(device) + 1;
 533         ifa = ifaddrs;
 534         while (ifa) {
 535                 if (strncmp(device, ifa->snf_ifa_name, devlen) == 0) {
 536                         boardnum = ifa->snf_ifa_boardnum;
 537                         break;
 538                 }
 539                 ifa = ifa->snf_ifa_next;
 540         }
 541         snf_freeifaddrs(ifaddrs);
 542
 543         if (ifa == NULL) {
 544                 /*
 545                  * If we can't find the device by name, support the name "snfX"
 546                  * and "snf10gX" where X is the board number.
 547                  */
 548                 if (sscanf(device, "snf10g%d", &boardnum) != 1 &&
 549                     sscanf(device, "snf%d", &boardnum) != 1) {
 550                         /* Nope, not a supported name */
 551                         *is_ours = 0;
 552                         return NULL;
 553                 }
 554         }
 555
 556         /* OK, it's probably ours. */
 557         *is_ours = 1;
 558
 559         p = PCAP_CREATE_COMMON(ebuf, struct pcap_snf);
 560         if (p == NULL)
 561                 return NULL;
 562         ps = p->priv;
 563
 564         /*
 565          * We support microsecond and nanosecond time stamps.
 566          */
 567         p->tstamp_precision_list = malloc(2 * sizeof(u_int));
 568         if (p->tstamp_precision_list == NULL) {
 569                 pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE, errno,
 570                     "malloc");
 571                 pcap_close(p);
 572                 return NULL;
 573         }
 574         p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
 575         p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
 576         p->tstamp_precision_count = 2;
 577
 578         p->activate_op = snf_activate;
 579         ps->snf_boardnum = boardnum;
 580         return p;
 581 }
 582
 583 #ifdef SNF_ONLY
 584 /*
 585  * This libpcap build supports only SNF cards, not regular network
 586  * interfaces..
 587  */
 588
 589 /*
 590  * There are no regular interfaces, just SNF interfaces.
 591  */
 592 int
 593 pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 594 {
 595         return (0);
 596 }
 597
 598 /*
 599  * Attempts to open a regular interface fail.
 600  */
 601 pcap_t *
 602 pcap_create_interface(const char *device, char *errbuf)
 603 {
 604         snprintf(errbuf, PCAP_ERRBUF_SIZE,
 605             "This version of libpcap only supports SNF cards");
 606         return NULL;
 607 }
 608
 609 /*
 610  * Libpcap version string.
 611  */
 612 const char *
 613 pcap_lib_version(void)
 614 {
 615         return (PCAP_VERSION_STRING " (SNF-only)");
 616 }
 617 #endif