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
  13 #include <ctype.h>
  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_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_get_stats: %s",
  59                          pcap_strerror(rc));
  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         n = 0;
 144         timeout = ps->snf_timeout;
 145         while (n < cnt || PACKET_COUNT_IS_UNLIMITED(cnt)) {
 146                 /*
 147                  * Has "pcap_breakloop()" been called?
 148                  */
 149                 if (p->break_loop) {
 150                         if (n == 0) {
 151                                 p->break_loop = 0;
 152                                 return (-2);
 153                         } else {
 154                                 return (n);
 155                         }
 156                 }
 157
 158                 err = snf_ring_recv(ps->snf_ring, timeout, &req);
 159
 160                 if (err) {
 161                         if (err == EBUSY || err == EAGAIN) {
 162                                 return (n);
 163                         }
 164                         else if (err == EINTR) {
 165                                 timeout = 0;
 166                                 continue;
 167                         }
 168                         else {
 169                                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_read: %s",
 170                                          pcap_strerror(err));
 171                                 return -1;
 172                         }
 173                 }
 174
 175                 caplen = req.length;
 176                 if (caplen > p->snapshot)
 177                         caplen = p->snapshot;
 178
 179                 if ((p->fcode.bf_insns == NULL) ||
 180                      bpf_filter(p->fcode.bf_insns, req.pkt_addr, req.length, caplen)) {
 181                         hdr.ts = snf_timestamp_to_timeval(req.timestamp, p->opt.tstamp_precision);
 182                         hdr.caplen = caplen;
 183                         hdr.len = req.length;
 184                         callback(user, &hdr, req.pkt_addr);
 185                 }
 186                 n++;
 187
 188                 /* After one successful packet is received, we won't block
 189                 * again for that timeout. */
 190                 if (timeout != 0)
 191                         timeout = 0;
 192         }
 193         return (n);
 194 }
 195
 196 static int
 197 snf_setfilter(pcap_t *p, struct bpf_program *fp)
 198 {
 199         if (!p)
 200                 return -1;
 201         if (!fp) {
 202                 strncpy(p->errbuf, "setfilter: No filter specified",
 203                         sizeof(p->errbuf));
 204                 return -1;
 205         }
 206
 207         /* Make our private copy of the filter */
 208
 209         if (install_bpf_program(p, fp) < 0)
 210                 return -1;
 211
 212         return (0);
 213 }
 214
 215 static int
 216 snf_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
 217 {
 218 #ifdef SNF_HAVE_INJECT_API
 219         struct pcap_snf *ps = p->priv;
 220         int rc;
 221         if (ps->snf_inj == NULL) {
 222                 rc = snf_inject_open(ps->snf_boardnum, 0, &ps->snf_inj);
 223                 if (rc) {
 224                         pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 225                                 "snf_inject_open: %s", pcap_strerror(rc));
 226                         return (-1);
 227                 }
 228         }
 229
 230         rc = snf_inject_send(ps->snf_inj, -1, 0, buf, size);
 231         if (!rc) {
 232                 return (size);
 233         }
 234         else {
 235                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "snf_inject_send: %s",
 236                          pcap_strerror(rc));
 237                 return (-1);
 238         }
 239 #else
 240         strlcpy(p->errbuf, "Sending packets isn't supported with this snf version",
 241             PCAP_ERRBUF_SIZE);
 242         return (-1);
 243 #endif
 244 }
 245
 246 static int
 247 snf_activate(pcap_t* p)
 248 {
 249         struct pcap_snf *ps = p->priv;
 250         char *device = p->opt.device;
 251         const char *nr = NULL;
 252         int err;
 253         int flags = -1, ring_id = -1;
 254
 255         if (device == NULL) {
 256                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 257                          "device is NULL: %s", pcap_strerror(errno));
 258                 return -1;
 259         }
 260
 261         /* In Libpcap, we set pshared by default if NUM_RINGS is set to > 1.
 262          * Since libpcap isn't thread-safe */
 263         if ((nr = getenv("SNF_FLAGS")) && *nr)
 264                 flags = strtol(nr, NULL, 0);
 265         else if ((nr = getenv("SNF_NUM_RINGS")) && *nr && atoi(nr) > 1)
 266                 flags = SNF_F_PSHARED;
 267         else
 268                 nr = NULL;
 269
 270
 271         /* Allow pcap_set_buffer_size() to set dataring_size.
 272          * Default is zero which allows setting from env SNF_DATARING_SIZE.
 273          * pcap_set_buffer_size() is in bytes while snf_open() accepts values
 274          * between 0 and 1048576 in Megabytes. Values in this range are
 275          * mapped to 1MB.
 276          */
 277         err = snf_open(ps->snf_boardnum,
 278                         0, /* let SNF API parse SNF_NUM_RINGS, if set */
 279                         NULL, /* default RSS, or use SNF_RSS_FLAGS env */
 280                         (p->opt.buffer_size > 0 && p->opt.buffer_size < 1048576) ? 1048576 : p->opt.buffer_size, /* default to SNF_DATARING_SIZE from env */
 281                         flags, /* may want pshared */
 282                         &ps->snf_handle);
 283         if (err != 0) {
 284                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 285                          "snf_open failed: %s", pcap_strerror(err));
 286                 return -1;
 287         }
 288
 289         if ((nr = getenv("SNF_PCAP_RING_ID")) && *nr) {
 290                 ring_id = (int) strtol(nr, NULL, 0);
 291         }
 292         err = snf_ring_open_id(ps->snf_handle, ring_id, &ps->snf_ring);
 293         if (err != 0) {
 294                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 295                          "snf_ring_open_id(ring=%d) failed: %s",
 296                          ring_id, pcap_strerror(err));
 297                 return -1;
 298         }
 299
 300         /*
 301          * Turn a negative snapshot value (invalid), a snapshot value of
 302          * 0 (unspecified), or a value bigger than the normal maximum
 303          * value, into the maximum allowed value.
 304          *
 305          * If some application really *needs* a bigger snapshot
 306          * length, we should just increase MAXIMUM_SNAPLEN.
 307          */
 308         if (p->snapshot <= 0 || p->snapshot > MAXIMUM_SNAPLEN)
 309                 p->snapshot = MAXIMUM_SNAPLEN;
 310
 311         if (p->opt.timeout <= 0)
 312                 ps->snf_timeout = -1;
 313         else
 314                 ps->snf_timeout = p->opt.timeout;
 315
 316         err = snf_start(ps->snf_handle);
 317         if (err != 0) {
 318                 pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 319                          "snf_start failed: %s", pcap_strerror(err));
 320                 return -1;
 321         }
 322
 323         /*
 324          * "select()" and "poll()" don't work on snf descriptors.
 325          */
 326 #ifndef _WIN32
 327         p->selectable_fd = -1;
 328 #endif /* !_WIN32 */
 329         p->linktype = DLT_EN10MB;
 330         p->read_op = snf_read;
 331         p->inject_op = snf_inject;
 332         p->setfilter_op = snf_setfilter;
 333         p->setdirection_op = NULL; /* Not implemented.*/
 334         p->set_datalink_op = snf_set_datalink;
 335         p->getnonblock_op = snf_getnonblock;
 336         p->setnonblock_op = snf_setnonblock;
 337         p->stats_op = snf_pcap_stats;
 338         p->cleanup_op = snf_platform_cleanup;
 339 #ifdef SNF_HAVE_INJECT_API
 340         ps->snf_inj = NULL;
 341 #endif
 342         return 0;
 343 }
 344
 345 #define MAX_DESC_LENGTH 128
 346 int
 347 snf_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
 348 {
 349         pcap_if_t *dev;
 350 #ifdef _WIN32
 351         struct sockaddr_in addr;
 352 #endif
 353         struct snf_ifaddrs *ifaddrs, *ifa;
 354         char name[MAX_DESC_LENGTH];
 355         char desc[MAX_DESC_LENGTH];
 356         int ret, allports = 0, merge = 0;
 357         const char *nr = NULL;
 358
 359         if (snf_init(SNF_VERSION_API)) {
 360                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 361                     "snf_getifaddrs: snf_init failed");
 362                 return (-1);
 363         }
 364
 365         if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL)
 366         {
 367                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 368                         "snf_getifaddrs: %s", pcap_strerror(errno));
 369                 return (-1);
 370         }
 371         if ((nr = getenv("SNF_FLAGS")) && *nr) {
 372                 errno = 0;
 373                 merge = strtol(nr, NULL, 0);
 374                 if (errno) {
 375                         (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 376                                 "snf_getifaddrs: SNF_FLAGS is not a valid number");
 377                         return (-1);
 378                 }
 379                 merge = merge & SNF_F_AGGREGATE_PORTMASK;
 380         }
 381
 382         for (ifa = ifaddrs; ifa != NULL; ifa = ifa->snf_ifa_next) {
 383                 /*
 384                  * Myricom SNF adapter ports may appear as regular
 385                  * network interfaces, which would already have been
 386                  * added to the list of adapters by pcap_platform_finddevs()
 387                  * if this isn't an SNF-only version of libpcap.
 388                  *
 389                  * Our create routine intercepts pcap_create() calls for
 390                  * those interfaces and arranges that they will be
 391                  * opened using the SNF API instead.
 392                  *
 393                  * So if we already have an entry for the device, we
 394                  * don't add an additional entry for it, we just
 395                  * update the description for it, if any, to indicate
 396                  * which snfN device it is.  Otherwise, we add an entry
 397                  * for it.
 398                  *
 399                  * In either case, if SNF_F_AGGREGATE_PORTMASK is set
 400                  * in SNF_FLAGS, we add this port to the bitmask
 401                  * of ports, which we use to generate a device
 402                  * we can use to capture on all ports.
 403                  *
 404                  * Generate the description string.  If port aggregation
 405                  * is set, use 2^{port number} as the unit number,
 406                  * rather than {port number}.
 407                  *
 408                  * XXX - do entries in this list have IP addresses for
 409                  * the port?  If so, should we add them to the
 410                  * entry for the device, if they're not already in the
 411                  * list of IP addresses for the device?
 412                  */
 413                 (void)pcap_snprintf(desc,MAX_DESC_LENGTH,"Myricom %ssnf%d",
 414                         merge ? "Merge Bitmask Port " : "",
 415                         merge ? 1 << ifa->snf_ifa_portnum : ifa->snf_ifa_portnum);
 416                 /*
 417                  * Add the port to the bitmask.
 418                  */
 419                 if (merge)
 420                         allports |= 1 << ifa->snf_ifa_portnum;
 421                 /*
 422                  * See if there's already an entry for the device
 423                  * with the name ifa->snf_ifa_name.
 424                  */
 425                 dev = find_dev(devlistp, ifa->snf_ifa_name);
 426                 if (dev != NULL) {
 427                         /*
 428                          * Yes.  Update its description.
 429                          */
 430                         char *desc_str;
 431
 432                         desc_str = strdup(desc);
 433                         if (desc_str == NULL) {
 434                                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 435                                     "snf_findalldevs strdup: %s", pcap_strerror(errno));
 436                                 return -1;
 437                         }
 438                         free(dev->description);
 439                         dev->description = desc_str;
 440                 } else {
 441                         /*
 442                          * No.  Add an entry for it.
 443                          */
 444                         dev = add_dev(devlistp, ifa->snf_ifa_name, 0, desc,
 445                             errbuf);
 446                         if (dev == NULL)
 447                                 return -1;
 448 #ifdef _WIN32
 449                         /*
 450                          * On Windows, fill in IP# from device name
 451                          */
 452                         ret = inet_pton(AF_INET, dev->name, &addr.sin_addr);
 453                         if (ret == 1) {
 454                                 /*
 455                                  * Successful conversion of device name
 456                                  * to IPv4 address.
 457                                  */
 458                                 addr.sin_family = AF_INET;
 459                                 if (add_addr_to_dev(dev, &addr, sizeof(addr),
 460                                     NULL, 0, NULL, 0, NULL, 0, errbuf) == -1)
 461                                         return -1;
 462                         } else if (ret == -1) {
 463                                 /*
 464                                  * Error.
 465                                  */
 466                                 (void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,"sinf_findalldevs inet_pton: %s", pcap_strerror(errno));
 467                                 return -1;
 468                         }
 469 #endif _WIN32
 470                 }
 471         }
 472         snf_freeifaddrs(ifaddrs);
 473         /*
 474          * Create a snfX entry if port aggregation is enabled
 475          */
 476         if (merge) {
 477                 /*
 478                  * Add a new entry with all ports bitmask
 479                  */
 480                 (void)pcap_snprintf(name,MAX_DESC_LENGTH,"snf%d",allports);
 481                 (void)pcap_snprintf(desc,MAX_DESC_LENGTH,"Myricom Merge Bitmask All Ports snf%d",
 482                         allports);
 483                 if (add_dev(devlistp, name, 0, desc, errbuf) == NULL)
 484                         return (-1);
 485                 /*
 486                  * XXX - should we give it a list of addresses with all
 487                  * the addresses for all the ports?
 488                  */
 489         }
 490
 491         return 0;
 492 }
 493
 494 pcap_t *
 495 snf_create(const char *device, char *ebuf, int *is_ours)
 496 {
 497         pcap_t *p;
 498         int boardnum = -1;
 499         struct snf_ifaddrs *ifaddrs, *ifa;
 500         size_t devlen;
 501         struct pcap_snf *ps;
 502
 503         if (snf_init(SNF_VERSION_API)) {
 504                 /* Can't initialize the API, so no SNF devices */
 505                 *is_ours = 0;
 506                 return NULL;
 507         }
 508
 509         /*
 510          * Match a given interface name to our list of interface names, from
 511          * which we can obtain the intended board number
 512          */
 513         if (snf_getifaddrs(&ifaddrs) || ifaddrs == NULL) {
 514                 /* Can't get SNF addresses */
 515                 *is_ours = 0;
 516                 return NULL;
 517         }
 518         devlen = strlen(device) + 1;
 519         ifa = ifaddrs;
 520         while (ifa) {
 521                 if (strncmp(device, ifa->snf_ifa_name, devlen) == 0) {
 522                         boardnum = ifa->snf_ifa_boardnum;
 523                         break;
 524                 }
 525                 ifa = ifa->snf_ifa_next;
 526         }
 527         snf_freeifaddrs(ifaddrs);
 528
 529         if (ifa == NULL) {
 530                 /*
 531                  * If we can't find the device by name, support the name "snfX"
 532                  * and "snf10gX" where X is the board number.
 533                  */
 534                 if (sscanf(device, "snf10g%d", &boardnum) != 1 &&
 535                     sscanf(device, "snf%d", &boardnum) != 1) {
 536                         /* Nope, not a supported name */
 537                         *is_ours = 0;
 538                         return NULL;
 539                 }
 540         }
 541
 542         /* OK, it's probably ours. */
 543         *is_ours = 1;
 544
 545         p = pcap_create_common(ebuf, sizeof (struct pcap_snf));
 546         if (p == NULL)
 547                 return NULL;
 548         ps = p->priv;
 549
 550         /*
 551          * We support microsecond and nanosecond time stamps.
 552          */
 553         p->tstamp_precision_count = 2;
 554         p->tstamp_precision_list = malloc(2 * sizeof(u_int));
 555         if (p->tstamp_precision_list == NULL) {
 556                 pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
 557                     pcap_strerror(errno));
 558                 pcap_close(p);
 559                 return NULL;
 560         }
 561         p->tstamp_precision_list[0] = PCAP_TSTAMP_PRECISION_MICRO;
 562         p->tstamp_precision_list[1] = PCAP_TSTAMP_PRECISION_NANO;
 563
 564         p->activate_op = snf_activate;
 565         ps->snf_boardnum = boardnum;
 566         return p;
 567 }
 568
 569 #ifdef SNF_ONLY
 570 /*
 571  * This libpcap build supports only SNF cards, not regular network
 572  * interfaces..
 573  */
 574
 575 /*
 576  * There are no regular interfaces, just SNF interfaces.
 577  */
 578 int
 579 pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 580 {
 581         return (0);
 582 }
 583
 584 /*
 585  * Attempts to open a regular interface fail.
 586  */
 587 pcap_t *
 588 pcap_create_interface(const char *device, char *errbuf)
 589 {
 590         pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
 591             "This version of libpcap only supports SNF cards");
 592         return NULL;
 593 }
 594
 595 /*
 596  * Libpcap version string.
 597  */
 598 const char *
 599 pcap_lib_version(void)
 600 {
 601         return (PCAP_VERSION_STRING " (SNF-only)");
 602 }
 603 #endif