external/bsd/libpcap/dist/pcap-nit.c

   1 /*      $NetBSD: pcap-nit.c,v 1.3 2015/03/31 21:39:42 christos Exp $    */
   2
   3 /*
   4  * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that: (1) source code distributions
   9  * retain the above copyright notice and this paragraph in its entirety, (2)
  10  * distributions including binary code include the above copyright notice and
  11  * this paragraph in its entirety in the documentation or other materials
  12  * provided with the distribution, and (3) all advertising materials mentioning
  13  * features or use of this software display the following acknowledgement:
  14  * ``This product includes software developed by the University of California,
  15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  16  * the University nor the names of its contributors may be used to endorse
  17  * or promote products derived from this software without specific prior
  18  * written permission.
  19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  22  */
  23
  24 #include <sys/cdefs.h>
  25 __RCSID("$NetBSD: pcap-nit.c,v 1.3 2015/03/31 21:39:42 christos Exp $");
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <sys/types.h>
  32 #include <sys/time.h>
  33 #include <sys/timeb.h>
  34 #include <sys/file.h>
  35 #include <sys/ioctl.h>
  36 #include <sys/socket.h>
  37
  38 #include <net/if.h>
  39 #include <net/nit.h>
  40
  41 #include <netinet/in.h>
  42 #include <netinet/in_systm.h>
  43 #include <netinet/ip.h>
  44 #include <netinet/if_ether.h>
  45 #include <netinet/ip_var.h>
  46 #include <netinet/udp.h>
  47 #include <netinet/udp_var.h>
  48 #include <netinet/tcp.h>
  49 #include <netinet/tcpip.h>
  50
  51 #include <ctype.h>
  52 #include <errno.h>
  53 #include <stdio.h>
  54
  55 #include "pcap-int.h"
  56
  57 #ifdef HAVE_OS_PROTO_H
  58 #include "os-proto.h"
  59 #endif
  60
  61 /*
  62  * The chunk size for NIT.  This is the amount of buffering
  63  * done for read calls.
  64  */
  65 #define CHUNKSIZE (2*1024)
  66
  67 /*
  68  * The total buffer space used by NIT.
  69  */
  70 #define BUFSPACE (4*CHUNKSIZE)
  71
  72 /* Forwards */
  73 static int nit_setflags(int, int, int, char *);
  74
  75 /*
  76  * Private data for capturing on NIT devices.
  77  */
  78 struct pcap_nit {
  79         struct pcap_stat stat;
  80 };
  81
  82 static int
  83 pcap_stats_nit(pcap_t *p, struct pcap_stat *ps)
  84 {
  85         struct pcap_nit *pn = p->priv;
  86
  87         /*
  88          * "ps_recv" counts packets handed to the filter, not packets
  89          * that passed the filter.  As filtering is done in userland,
  90          * this does not include packets dropped because we ran out
  91          * of buffer space.
  92          *
  93          * "ps_drop" presumably counts packets dropped by the socket
  94          * because of flow control requirements or resource exhaustion;
  95          * it doesn't count packets dropped by the interface driver.
  96          * As filtering is done in userland, it counts packets regardless
  97          * of whether they would've passed the filter.
  98          *
  99          * These statistics don't include packets not yet read from the
 100          * kernel by libpcap or packets not yet read from libpcap by the
 101          * application.
 102          */
 103         *ps = pn->stat;
 104         return (0);
 105 }
 106
 107 static int
 108 pcap_read_nit(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
 109 {
 110         struct pcap_nit *pn = p->priv;
 111         register int cc, n;
 112         register u_char *bp, *cp, *ep;
 113         register struct nit_hdr *nh;
 114         register int caplen;
 115
 116         cc = p->cc;
 117         if (cc == 0) {
 118                 cc = read(p->fd, (char *)p->buffer, p->bufsize);
 119                 if (cc < 0) {
 120                         if (errno == EWOULDBLOCK)
 121                                 return (0);
 122                         snprintf(p->errbuf, sizeof(p->errbuf), "pcap_read: %s",
 123                                 pcap_strerror(errno));
 124                         return (-1);
 125                 }
 126                 bp = p->buffer;
 127         } else
 128                 bp = p->bp;
 129
 130         /*
 131          * Loop through each packet.  The increment expression
 132          * rounds up to the next int boundary past the end of
 133          * the previous packet.
 134          */
 135         n = 0;
 136         ep = bp + cc;
 137         while (bp < ep) {
 138                 /*
 139                  * Has "pcap_breakloop()" been called?
 140                  * If so, return immediately - if we haven't read any
 141                  * packets, clear the flag and return -2 to indicate
 142                  * that we were told to break out of the loop, otherwise
 143                  * leave the flag set, so that the *next* call will break
 144                  * out of the loop without having read any packets, and
 145                  * return the number of packets we've processed so far.
 146                  */
 147                 if (p->break_loop) {
 148                         if (n == 0) {
 149                                 p->break_loop = 0;
 150                                 return (-2);
 151                         } else {
 152                                 p->cc = ep - bp;
 153                                 p->bp = bp;
 154                                 return (n);
 155                         }
 156                 }
 157
 158                 nh = (struct nit_hdr *)bp;
 159                 cp = bp + sizeof(*nh);
 160
 161                 switch (nh->nh_state) {
 162
 163                 case NIT_CATCH:
 164                         break;
 165
 166                 case NIT_NOMBUF:
 167                 case NIT_NOCLUSTER:
 168                 case NIT_NOSPACE:
 169                         pn->stat.ps_drop = nh->nh_dropped;
 170                         continue;
 171
 172                 case NIT_SEQNO:
 173                         continue;
 174
 175                 default:
 176                         snprintf(p->errbuf, sizeof(p->errbuf),
 177                             "bad nit state %d", nh->nh_state);
 178                         return (-1);
 179                 }
 180                 ++pn->stat.ps_recv;
 181                 bp += ((sizeof(struct nit_hdr) + nh->nh_datalen +
 182                     sizeof(int) - 1) & ~(sizeof(int) - 1));
 183
 184                 caplen = nh->nh_wirelen;
 185                 if (caplen > p->snapshot)
 186                         caplen = p->snapshot;
 187                 if (bpf_filter(p->fcode.bf_insns, cp, nh->nh_wirelen, caplen)) {
 188                         struct pcap_pkthdr h;
 189                         h.ts = nh->nh_timestamp;
 190                         h.len = nh->nh_wirelen;
 191                         h.caplen = caplen;
 192                         (*callback)(user, &h, cp);
 193                         if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) {
 194                                 p->cc = ep - bp;
 195                                 p->bp = bp;
 196                                 return (n);
 197                         }
 198                 }
 199         }
 200         p->cc = 0;
 201         return (n);
 202 }
 203
 204 static int
 205 pcap_inject_nit(pcap_t *p, const void *buf, size_t size)
 206 {
 207         struct sockaddr sa;
 208         int ret;
 209
 210         memset(&sa, 0, sizeof(sa));
 211         strncpy(sa.sa_data, device, sizeof(sa.sa_data));
 212         ret = sendto(p->fd, buf, size, 0, &sa, sizeof(sa));
 213         if (ret == -1) {
 214                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s",
 215                     pcap_strerror(errno));
 216                 return (-1);
 217         }
 218         return (ret);
 219 }
 220
 221 static int
 222 nit_setflags(pcap_t *p)
 223 {
 224         struct nit_ioc nioc;
 225
 226         memset(&nioc, 0, sizeof(nioc));
 227         nioc.nioc_typetomatch = NT_ALLTYPES;
 228         nioc.nioc_snaplen = p->snapshot;
 229         nioc.nioc_bufalign = sizeof(int);
 230         nioc.nioc_bufoffset = 0;
 231
 232         if (p->opt.buffer_size != 0)
 233                 nioc.nioc_bufspace = p->opt.buffer_size;
 234         else {
 235                 /* Default buffer size */
 236                 nioc.nioc_bufspace = BUFSPACE;
 237         }
 238
 239         if (p->opt.immediate) {
 240                 /*
 241                  * XXX - will this cause packets to be delivered immediately?
 242                  * XXX - given that this is for SunOS prior to 4.0, do
 243                  * we care?
 244                  */
 245                 nioc.nioc_chunksize = 0;
 246         } else
 247                 nioc.nioc_chunksize = CHUNKSIZE;
 248         if (p->opt.timeout != 0) {
 249                 nioc.nioc_flags |= NF_TIMEOUT;
 250                 nioc.nioc_timeout.tv_sec = p->opt.timeout / 1000;
 251                 nioc.nioc_timeout.tv_usec = (p->opt.timeout * 1000) % 1000000;
 252         }
 253         if (p->opt.promisc)
 254                 nioc.nioc_flags |= NF_PROMISC;
 255
 256         if (ioctl(p->fd, SIOCSNIT, &nioc) < 0) {
 257                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCSNIT: %s",
 258                     pcap_strerror(errno));
 259                 return (-1);
 260         }
 261         return (0);
 262 }
 263
 264 static int
 265 pcap_activate_nit(pcap_t *p)
 266 {
 267         int fd;
 268         struct sockaddr_nit snit;
 269
 270         if (p->opt.rfmon) {
 271                 /*
 272                  * No monitor mode on SunOS 3.x or earlier (no
 273                  * Wi-Fi *devices* for the hardware that supported
 274                  * them!).
 275                  */
 276                 return (PCAP_ERROR_RFMON_NOTSUP);
 277         }
 278
 279         if (p->snapshot < 96)
 280                 /*
 281                  * NIT requires a snapshot length of at least 96.
 282                  */
 283                 p->snapshot = 96;
 284
 285         memset(p, 0, sizeof(*p));
 286         p->fd = fd = socket(AF_NIT, SOCK_RAW, NITPROTO_RAW);
 287         if (fd < 0) {
 288                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 289                     "socket: %s", pcap_strerror(errno));
 290                 goto bad;
 291         }
 292         snit.snit_family = AF_NIT;
 293         (void)strncpy(snit.snit_ifname, p->opt.source, NITIFSIZ);
 294
 295         if (bind(fd, (struct sockaddr *)&snit, sizeof(snit))) {
 296                 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
 297                     "bind: %s: %s", snit.snit_ifname, pcap_strerror(errno));
 298                 goto bad;
 299         }
 300         if (nit_setflags(p) < 0)
 301                 goto bad;
 302
 303         /*
 304          * NIT supports only ethernets.
 305          */
 306         p->linktype = DLT_EN10MB;
 307
 308         p->bufsize = BUFSPACE;
 309         p->buffer = (u_char *)malloc(p->bufsize);
 310         if (p->buffer == NULL) {
 311                 strlcpy(p->errbuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE);
 312                 goto bad;
 313         }
 314
 315         /*
 316          * "p->fd" is a socket, so "select()" should work on it.
 317          */
 318         p->selectable_fd = p->fd;
 319
 320         /*
 321          * This is (presumably) a real Ethernet capture; give it a
 322          * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so
 323          * that an application can let you choose it, in case you're
 324          * capturing DOCSIS traffic that a Cisco Cable Modem
 325          * Termination System is putting out onto an Ethernet (it
 326          * doesn't put an Ethernet header onto the wire, it puts raw
 327          * DOCSIS frames out on the wire inside the low-level
 328          * Ethernet framing).
 329          */
 330         p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2);
 331         /*
 332          * If that fails, just leave the list empty.
 333          */
 334         if (p->dlt_list != NULL) {
 335                 p->dlt_list[0] = DLT_EN10MB;
 336                 p->dlt_list[1] = DLT_DOCSIS;
 337                 p->dlt_count = 2;
 338         }
 339
 340         p->read_op = pcap_read_nit;
 341         p->inject_op = pcap_inject_nit;
 342         p->setfilter_op = install_bpf_program;  /* no kernel filtering */
 343         p->setdirection_op = NULL;      /* Not implemented. */
 344         p->set_datalink_op = NULL;      /* can't change data link type */
 345         p->getnonblock_op = pcap_getnonblock_fd;
 346         p->setnonblock_op = pcap_setnonblock_fd;
 347         p->stats_op = pcap_stats_nit;
 348
 349         return (0);
 350  bad:
 351         pcap_cleanup_live_common(p);
 352         return (PCAP_ERROR);
 353 }
 354
 355 pcap_t *
 356 pcap_create_interface(const char *device, char *ebuf)
 357 {
 358         pcap_t *p;
 359
 360         p = pcap_create_common(device, ebuf, sizeof (struct pcap_nit));
 361         if (p == NULL)
 362                 return (NULL);
 363
 364         p->activate_op = pcap_activate_nit;
 365         return (p);
 366 }
 367
 368 int
 369 pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 370 {
 371         return (0);
 372 }