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