The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 1990, 1991, 1992, 1993, 1994, 1995, 1996 |
| 3 | * The Regents of the University of California. All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that: (1) source code distributions |
| 7 | * retain the above copyright notice and this paragraph in its entirety, (2) |
| 8 | * distributions including binary code include the above copyright notice and |
| 9 | * this paragraph in its entirety in the documentation or other materials |
| 10 | * provided with the distribution, and (3) all advertising materials mentioning |
| 11 | * features or use of this software display the following acknowledgement: |
| 12 | * ``This product includes software developed by the University of California, |
| 13 | * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
| 14 | * the University nor the names of its contributors may be used to endorse |
| 15 | * or promote products derived from this software without specific prior |
| 16 | * written permission. |
| 17 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
| 18 | * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
| 19 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 20 | * |
| 21 | * packet filter subroutines for tcpdump |
| 22 | * Extraction/creation by Jeffrey Mogul, DECWRL |
| 23 | */ |
| 24 | |
| 25 | #ifndef lint |
| 26 | static const char rcsid[] _U_ = |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 27 | "@(#) $Header: /tcpdump/master/libpcap/pcap-pf.c,v 1.97 2008-04-14 20:40:58 guy Exp $ (LBL)"; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 28 | #endif |
| 29 | |
| 30 | #ifdef HAVE_CONFIG_H |
| 31 | #include "config.h" |
| 32 | #endif |
| 33 | |
| 34 | #include <sys/types.h> |
| 35 | #include <sys/time.h> |
| 36 | #include <sys/timeb.h> |
| 37 | #include <sys/socket.h> |
| 38 | #include <sys/file.h> |
| 39 | #include <sys/ioctl.h> |
| 40 | #include <net/pfilt.h> |
| 41 | |
| 42 | struct mbuf; |
| 43 | struct rtentry; |
| 44 | #include <net/if.h> |
| 45 | |
| 46 | #include <netinet/in.h> |
| 47 | #include <netinet/in_systm.h> |
| 48 | #include <netinet/ip.h> |
| 49 | #include <netinet/if_ether.h> |
| 50 | #include <netinet/ip_var.h> |
| 51 | #include <netinet/udp.h> |
| 52 | #include <netinet/udp_var.h> |
| 53 | #include <netinet/tcp.h> |
| 54 | #include <netinet/tcpip.h> |
| 55 | |
| 56 | #include <ctype.h> |
| 57 | #include <errno.h> |
| 58 | #include <netdb.h> |
| 59 | #include <stdio.h> |
| 60 | #include <stdlib.h> |
| 61 | #include <string.h> |
| 62 | #include <unistd.h> |
| 63 | |
| 64 | /* |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 65 | * Make "pcap.h" not include "pcap/bpf.h"; we are going to include the |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 66 | * native OS version, as we need various BPF ioctls from it. |
| 67 | */ |
| 68 | #define PCAP_DONT_INCLUDE_PCAP_BPF_H |
| 69 | #include <net/bpf.h> |
| 70 | |
| 71 | #include "pcap-int.h" |
| 72 | |
| 73 | #ifdef HAVE_OS_PROTO_H |
| 74 | #include "os-proto.h" |
| 75 | #endif |
| 76 | |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 77 | /* |
| 78 | * FDDI packets are padded to make everything line up on a nice boundary. |
| 79 | */ |
| 80 | #define PCAP_FDDIPAD 3 |
| 81 | |
| 82 | /* |
| 83 | * Private data for capturing on Ultrix and DEC OSF/1^WDigital UNIX^W^W |
| 84 | * Tru64 UNIX packetfilter devices. |
| 85 | */ |
| 86 | struct pcap_pf { |
| 87 | int filtering_in_kernel; /* using kernel filter */ |
| 88 | u_long TotPkts; /* can't oflow for 79 hrs on ether */ |
| 89 | u_long TotAccepted; /* count accepted by filter */ |
| 90 | u_long TotDrops; /* count of dropped packets */ |
| 91 | long TotMissed; /* missed by i/f during this run */ |
| 92 | long OrigMissed; /* missed by i/f before this run */ |
| 93 | }; |
| 94 | |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 95 | static int pcap_setfilter_pf(pcap_t *, struct bpf_program *); |
| 96 | |
| 97 | /* |
| 98 | * BUFSPACE is the size in bytes of the packet read buffer. Most tcpdump |
| 99 | * applications aren't going to need more than 200 bytes of packet header |
| 100 | * and the read shouldn't return more packets than packetfilter's internal |
| 101 | * queue limit (bounded at 256). |
| 102 | */ |
| 103 | #define BUFSPACE (200 * 256) |
| 104 | |
| 105 | static int |
| 106 | pcap_read_pf(pcap_t *pc, int cnt, pcap_handler callback, u_char *user) |
| 107 | { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 108 | struct pcap_pf *pf = pc->priv; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 109 | register u_char *p, *bp; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 110 | register int cc, n, buflen, inc; |
| 111 | register struct enstamp *sp; |
| 112 | #ifdef LBL_ALIGN |
| 113 | struct enstamp stamp; |
| 114 | #endif |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 115 | register int pad; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 116 | |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 117 | again: |
| 118 | cc = pc->cc; |
| 119 | if (cc == 0) { |
| 120 | cc = read(pc->fd, (char *)pc->buffer + pc->offset, pc->bufsize); |
| 121 | if (cc < 0) { |
| 122 | if (errno == EWOULDBLOCK) |
| 123 | return (0); |
| 124 | if (errno == EINVAL && |
| 125 | lseek(pc->fd, 0L, SEEK_CUR) + pc->bufsize < 0) { |
| 126 | /* |
| 127 | * Due to a kernel bug, after 2^31 bytes, |
| 128 | * the kernel file offset overflows and |
| 129 | * read fails with EINVAL. The lseek() |
| 130 | * to 0 will fix things. |
| 131 | */ |
| 132 | (void)lseek(pc->fd, 0L, SEEK_SET); |
| 133 | goto again; |
| 134 | } |
| 135 | snprintf(pc->errbuf, sizeof(pc->errbuf), "pf read: %s", |
| 136 | pcap_strerror(errno)); |
| 137 | return (-1); |
| 138 | } |
| 139 | bp = pc->buffer + pc->offset; |
| 140 | } else |
| 141 | bp = pc->bp; |
| 142 | /* |
| 143 | * Loop through each packet. |
| 144 | */ |
| 145 | n = 0; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 146 | pad = pc->fddipad; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 147 | while (cc > 0) { |
| 148 | /* |
| 149 | * Has "pcap_breakloop()" been called? |
| 150 | * If so, return immediately - if we haven't read any |
| 151 | * packets, clear the flag and return -2 to indicate |
| 152 | * that we were told to break out of the loop, otherwise |
| 153 | * leave the flag set, so that the *next* call will break |
| 154 | * out of the loop without having read any packets, and |
| 155 | * return the number of packets we've processed so far. |
| 156 | */ |
| 157 | if (pc->break_loop) { |
| 158 | if (n == 0) { |
| 159 | pc->break_loop = 0; |
| 160 | return (-2); |
| 161 | } else { |
| 162 | pc->cc = cc; |
| 163 | pc->bp = bp; |
| 164 | return (n); |
| 165 | } |
| 166 | } |
| 167 | if (cc < sizeof(*sp)) { |
| 168 | snprintf(pc->errbuf, sizeof(pc->errbuf), |
| 169 | "pf short read (%d)", cc); |
| 170 | return (-1); |
| 171 | } |
| 172 | #ifdef LBL_ALIGN |
| 173 | if ((long)bp & 3) { |
| 174 | sp = &stamp; |
| 175 | memcpy((char *)sp, (char *)bp, sizeof(*sp)); |
| 176 | } else |
| 177 | #endif |
| 178 | sp = (struct enstamp *)bp; |
| 179 | if (sp->ens_stamplen != sizeof(*sp)) { |
| 180 | snprintf(pc->errbuf, sizeof(pc->errbuf), |
| 181 | "pf short stamplen (%d)", |
| 182 | sp->ens_stamplen); |
| 183 | return (-1); |
| 184 | } |
| 185 | |
| 186 | p = bp + sp->ens_stamplen; |
| 187 | buflen = sp->ens_count; |
| 188 | if (buflen > pc->snapshot) |
| 189 | buflen = pc->snapshot; |
| 190 | |
| 191 | /* Calculate inc before possible pad update */ |
| 192 | inc = ENALIGN(buflen + sp->ens_stamplen); |
| 193 | cc -= inc; |
| 194 | bp += inc; |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 195 | pf->TotPkts++; |
| 196 | pf->TotDrops += sp->ens_dropped; |
| 197 | pf->TotMissed = sp->ens_ifoverflows; |
| 198 | if (pf->OrigMissed < 0) |
| 199 | pf->OrigMissed = pf->TotMissed; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 200 | |
| 201 | /* |
| 202 | * Short-circuit evaluation: if using BPF filter |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 203 | * in kernel, no need to do it now - we already know |
| 204 | * the packet passed the filter. |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 205 | * |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 206 | * Note: the filter code was generated assuming |
| 207 | * that pc->fddipad was the amount of padding |
| 208 | * before the header, as that's what's required |
| 209 | * in the kernel, so we run the filter before |
| 210 | * skipping that padding. |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 211 | */ |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 212 | if (pf->filtering_in_kernel || |
| 213 | bpf_filter(pc->fcode.bf_insns, p, sp->ens_count, buflen)) { |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 214 | struct pcap_pkthdr h; |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 215 | pf->TotAccepted++; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 216 | h.ts = sp->ens_tstamp; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 217 | h.len = sp->ens_count - pad; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 218 | p += pad; |
| 219 | buflen -= pad; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 220 | h.caplen = buflen; |
| 221 | (*callback)(user, &h, p); |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 222 | if (++n >= cnt && !PACKET_COUNT_IS_UNLIMITED(cnt)) { |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 223 | pc->cc = cc; |
| 224 | pc->bp = bp; |
| 225 | return (n); |
| 226 | } |
| 227 | } |
| 228 | } |
| 229 | pc->cc = 0; |
| 230 | return (n); |
| 231 | } |
| 232 | |
| 233 | static int |
| 234 | pcap_inject_pf(pcap_t *p, const void *buf, size_t size) |
| 235 | { |
| 236 | int ret; |
| 237 | |
| 238 | ret = write(p->fd, buf, size); |
| 239 | if (ret == -1) { |
| 240 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "send: %s", |
| 241 | pcap_strerror(errno)); |
| 242 | return (-1); |
| 243 | } |
| 244 | return (ret); |
| 245 | } |
| 246 | |
| 247 | static int |
| 248 | pcap_stats_pf(pcap_t *p, struct pcap_stat *ps) |
| 249 | { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 250 | struct pcap_pf *pf = p->priv; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 251 | |
| 252 | /* |
| 253 | * If packet filtering is being done in the kernel: |
| 254 | * |
| 255 | * "ps_recv" counts only packets that passed the filter. |
| 256 | * This does not include packets dropped because we |
| 257 | * ran out of buffer space. (XXX - perhaps it should, |
| 258 | * by adding "ps_drop" to "ps_recv", for compatibility |
| 259 | * with some other platforms. On the other hand, on |
| 260 | * some platforms "ps_recv" counts only packets that |
| 261 | * passed the filter, and on others it counts packets |
| 262 | * that didn't pass the filter....) |
| 263 | * |
| 264 | * "ps_drop" counts packets that passed the kernel filter |
| 265 | * (if any) but were dropped because the input queue was |
| 266 | * full. |
| 267 | * |
| 268 | * "ps_ifdrop" counts packets dropped by the network |
| 269 | * inteface (regardless of whether they would have passed |
| 270 | * the input filter, of course). |
| 271 | * |
| 272 | * If packet filtering is not being done in the kernel: |
| 273 | * |
| 274 | * "ps_recv" counts only packets that passed the filter. |
| 275 | * |
| 276 | * "ps_drop" counts packets that were dropped because the |
| 277 | * input queue was full, regardless of whether they passed |
| 278 | * the userland filter. |
| 279 | * |
| 280 | * "ps_ifdrop" counts packets dropped by the network |
| 281 | * inteface (regardless of whether they would have passed |
| 282 | * the input filter, of course). |
| 283 | * |
| 284 | * These statistics don't include packets not yet read from |
| 285 | * the kernel by libpcap, but they may include packets not |
| 286 | * yet read from libpcap by the application. |
| 287 | */ |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 288 | ps->ps_recv = pf->TotAccepted; |
| 289 | ps->ps_drop = pf->TotDrops; |
| 290 | ps->ps_ifdrop = pf->TotMissed - pf->OrigMissed; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 291 | return (0); |
| 292 | } |
| 293 | |
| 294 | /* |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 295 | * We include the OS's <net/bpf.h>, not our "pcap/bpf.h", so we probably |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 296 | * don't get DLT_DOCSIS defined. |
| 297 | */ |
| 298 | #ifndef DLT_DOCSIS |
| 299 | #define DLT_DOCSIS 143 |
| 300 | #endif |
| 301 | |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 302 | static int |
| 303 | pcap_activate_pf(pcap_t *p) |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 304 | { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 305 | struct pcap_pf *pf = p->priv; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 306 | short enmode; |
| 307 | int backlog = -1; /* request the most */ |
| 308 | struct enfilter Filter; |
| 309 | struct endevp devparams; |
| 310 | |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 311 | /* |
| 312 | * Initially try a read/write open (to allow the inject |
| 313 | * method to work). If that fails due to permission |
| 314 | * issues, fall back to read-only. This allows a |
| 315 | * non-root user to be granted specific access to pcap |
| 316 | * capabilities via file permissions. |
| 317 | * |
| 318 | * XXX - we should have an API that has a flag that |
| 319 | * controls whether to open read-only or read-write, |
| 320 | * so that denial of permission to send (or inability |
| 321 | * to send, if sending packets isn't supported on |
| 322 | * the device in question) can be indicated at open |
| 323 | * time. |
| 324 | * |
| 325 | * XXX - we assume here that "pfopen()" does not, in fact, modify |
| 326 | * its argument, even though it takes a "char *" rather than a |
| 327 | * "const char *" as its first argument. That appears to be |
| 328 | * the case, at least on Digital UNIX 4.0. |
| 329 | */ |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 330 | p->fd = pfopen(p->opt.source, O_RDWR); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 331 | if (p->fd == -1 && errno == EACCES) |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 332 | p->fd = pfopen(p->opt.source, O_RDONLY); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 333 | if (p->fd < 0) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 334 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "pf open: %s: %s\n\ |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 335 | your system may not be properly configured; see the packetfilter(4) man page\n", |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 336 | p->opt.source, pcap_strerror(errno)); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 337 | goto bad; |
| 338 | } |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 339 | pf->OrigMissed = -1; |
| 340 | enmode = ENTSTAMP|ENNONEXCL; |
| 341 | if (!p->opt.immediate) |
| 342 | enmode |= ENBATCH; |
| 343 | if (p->opt.promisc) |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 344 | enmode |= ENPROMISC; |
| 345 | if (ioctl(p->fd, EIOCMBIS, (caddr_t)&enmode) < 0) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 346 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "EIOCMBIS: %s", |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 347 | pcap_strerror(errno)); |
| 348 | goto bad; |
| 349 | } |
| 350 | #ifdef ENCOPYALL |
| 351 | /* Try to set COPYALL mode so that we see packets to ourself */ |
| 352 | enmode = ENCOPYALL; |
| 353 | (void)ioctl(p->fd, EIOCMBIS, (caddr_t)&enmode);/* OK if this fails */ |
| 354 | #endif |
| 355 | /* set the backlog */ |
| 356 | if (ioctl(p->fd, EIOCSETW, (caddr_t)&backlog) < 0) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 357 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "EIOCSETW: %s", |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 358 | pcap_strerror(errno)); |
| 359 | goto bad; |
| 360 | } |
| 361 | /* discover interface type */ |
| 362 | if (ioctl(p->fd, EIOCDEVP, (caddr_t)&devparams) < 0) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 363 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "EIOCDEVP: %s", |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 364 | pcap_strerror(errno)); |
| 365 | goto bad; |
| 366 | } |
| 367 | /* HACK: to compile prior to Ultrix 4.2 */ |
| 368 | #ifndef ENDT_FDDI |
| 369 | #define ENDT_FDDI 4 |
| 370 | #endif |
| 371 | switch (devparams.end_dev_type) { |
| 372 | |
| 373 | case ENDT_10MB: |
| 374 | p->linktype = DLT_EN10MB; |
| 375 | p->offset = 2; |
| 376 | /* |
| 377 | * This is (presumably) a real Ethernet capture; give it a |
| 378 | * link-layer-type list with DLT_EN10MB and DLT_DOCSIS, so |
| 379 | * that an application can let you choose it, in case you're |
| 380 | * capturing DOCSIS traffic that a Cisco Cable Modem |
| 381 | * Termination System is putting out onto an Ethernet (it |
| 382 | * doesn't put an Ethernet header onto the wire, it puts raw |
| 383 | * DOCSIS frames out on the wire inside the low-level |
| 384 | * Ethernet framing). |
| 385 | */ |
| 386 | p->dlt_list = (u_int *) malloc(sizeof(u_int) * 2); |
| 387 | /* |
| 388 | * If that fails, just leave the list empty. |
| 389 | */ |
| 390 | if (p->dlt_list != NULL) { |
| 391 | p->dlt_list[0] = DLT_EN10MB; |
| 392 | p->dlt_list[1] = DLT_DOCSIS; |
| 393 | p->dlt_count = 2; |
| 394 | } |
| 395 | break; |
| 396 | |
| 397 | case ENDT_FDDI: |
| 398 | p->linktype = DLT_FDDI; |
| 399 | break; |
| 400 | |
| 401 | #ifdef ENDT_SLIP |
| 402 | case ENDT_SLIP: |
| 403 | p->linktype = DLT_SLIP; |
| 404 | break; |
| 405 | #endif |
| 406 | |
| 407 | #ifdef ENDT_PPP |
| 408 | case ENDT_PPP: |
| 409 | p->linktype = DLT_PPP; |
| 410 | break; |
| 411 | #endif |
| 412 | |
| 413 | #ifdef ENDT_LOOPBACK |
| 414 | case ENDT_LOOPBACK: |
| 415 | /* |
| 416 | * It appears to use Ethernet framing, at least on |
| 417 | * Digital UNIX 4.0. |
| 418 | */ |
| 419 | p->linktype = DLT_EN10MB; |
| 420 | p->offset = 2; |
| 421 | break; |
| 422 | #endif |
| 423 | |
| 424 | #ifdef ENDT_TRN |
| 425 | case ENDT_TRN: |
| 426 | p->linktype = DLT_IEEE802; |
| 427 | break; |
| 428 | #endif |
| 429 | |
| 430 | default: |
| 431 | /* |
| 432 | * XXX - what about ENDT_IEEE802? The pfilt.h header |
| 433 | * file calls this "IEEE 802 networks (non-Ethernet)", |
| 434 | * but that doesn't specify a specific link layer type; |
| 435 | * it could be 802.4, or 802.5 (except that 802.5 is |
| 436 | * ENDT_TRN), or 802.6, or 802.11, or.... That's why |
| 437 | * DLT_IEEE802 was hijacked to mean Token Ring in various |
| 438 | * BSDs, and why we went along with that hijacking. |
| 439 | * |
| 440 | * XXX - what about ENDT_HDLC and ENDT_NULL? |
| 441 | * Presumably, as ENDT_OTHER is just "Miscellaneous |
| 442 | * framing", there's not much we can do, as that |
| 443 | * doesn't specify a particular type of header. |
| 444 | */ |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 445 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
| 446 | "unknown data-link type %u", devparams.end_dev_type); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 447 | goto bad; |
| 448 | } |
| 449 | /* set truncation */ |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 450 | if (p->linktype == DLT_FDDI) { |
| 451 | p->fddipad = PCAP_FDDIPAD; |
| 452 | |
| 453 | /* packetfilter includes the padding in the snapshot */ |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 454 | p->snapshot += PCAP_FDDIPAD; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 455 | } else |
| 456 | p->fddipad = 0; |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 457 | if (ioctl(p->fd, EIOCTRUNCATE, (caddr_t)&p->snapshot) < 0) { |
| 458 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "EIOCTRUNCATE: %s", |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 459 | pcap_strerror(errno)); |
| 460 | goto bad; |
| 461 | } |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 462 | /* accept all packets */ |
| 463 | memset(&Filter, 0, sizeof(Filter)); |
| 464 | Filter.enf_Priority = 37; /* anything > 2 */ |
| 465 | Filter.enf_FilterLen = 0; /* means "always true" */ |
| 466 | if (ioctl(p->fd, EIOCSETF, (caddr_t)&Filter) < 0) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 467 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "EIOCSETF: %s", |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 468 | pcap_strerror(errno)); |
| 469 | goto bad; |
| 470 | } |
| 471 | |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 472 | if (p->opt.timeout != 0) { |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 473 | struct timeval timeout; |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 474 | timeout.tv_sec = p->opt.timeout / 1000; |
| 475 | timeout.tv_usec = (p->opt.timeout * 1000) % 1000000; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 476 | if (ioctl(p->fd, EIOCSRTIMEOUT, (caddr_t)&timeout) < 0) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 477 | snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "EIOCSRTIMEOUT: %s", |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 478 | pcap_strerror(errno)); |
| 479 | goto bad; |
| 480 | } |
| 481 | } |
| 482 | |
| 483 | p->bufsize = BUFSPACE; |
| 484 | p->buffer = (u_char*)malloc(p->bufsize + p->offset); |
| 485 | if (p->buffer == NULL) { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 486 | strlcpy(p->errbuf, pcap_strerror(errno), PCAP_ERRBUF_SIZE); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 487 | goto bad; |
| 488 | } |
| 489 | |
| 490 | /* |
| 491 | * "select()" and "poll()" work on packetfilter devices. |
| 492 | */ |
| 493 | p->selectable_fd = p->fd; |
| 494 | |
| 495 | p->read_op = pcap_read_pf; |
| 496 | p->inject_op = pcap_inject_pf; |
| 497 | p->setfilter_op = pcap_setfilter_pf; |
| 498 | p->setdirection_op = NULL; /* Not implemented. */ |
| 499 | p->set_datalink_op = NULL; /* can't change data link type */ |
| 500 | p->getnonblock_op = pcap_getnonblock_fd; |
| 501 | p->setnonblock_op = pcap_setnonblock_fd; |
| 502 | p->stats_op = pcap_stats_pf; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 503 | |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 504 | return (0); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 505 | bad: |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 506 | pcap_cleanup_live_common(p); |
| 507 | return (PCAP_ERROR); |
| 508 | } |
| 509 | |
| 510 | pcap_t * |
| 511 | pcap_create_interface(const char *device, char *ebuf) |
| 512 | { |
| 513 | pcap_t *p; |
| 514 | |
| 515 | p = pcap_create_common(device, ebuf, sizeof (struct pcap_pf)); |
| 516 | if (p == NULL) |
| 517 | return (NULL); |
| 518 | |
| 519 | p->activate_op = pcap_activate_pf; |
| 520 | return (p); |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 521 | } |
| 522 | |
| 523 | int |
| 524 | pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) |
| 525 | { |
| 526 | return (0); |
| 527 | } |
| 528 | |
| 529 | static int |
| 530 | pcap_setfilter_pf(pcap_t *p, struct bpf_program *fp) |
| 531 | { |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 532 | struct pcap_pf *pf = p->priv; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 533 | struct bpf_version bv; |
| 534 | |
| 535 | /* |
| 536 | * See if BIOCVERSION works. If not, we assume the kernel doesn't |
| 537 | * support BPF-style filters (it's not documented in the bpf(7) |
| 538 | * or packetfiler(7) man pages, but the code used to fail if |
| 539 | * BIOCSETF worked but BIOCVERSION didn't, and I've seen it do |
| 540 | * kernel filtering in DU 4.0, so presumably BIOCVERSION works |
| 541 | * there, at least). |
| 542 | */ |
| 543 | if (ioctl(p->fd, BIOCVERSION, (caddr_t)&bv) >= 0) { |
| 544 | /* |
| 545 | * OK, we have the version of the BPF interpreter; |
| 546 | * is it the same major version as us, and the same |
| 547 | * or better minor version? |
| 548 | */ |
| 549 | if (bv.bv_major == BPF_MAJOR_VERSION && |
| 550 | bv.bv_minor >= BPF_MINOR_VERSION) { |
| 551 | /* |
| 552 | * Yes. Try to install the filter. |
| 553 | */ |
| 554 | if (ioctl(p->fd, BIOCSETF, (caddr_t)fp) < 0) { |
| 555 | snprintf(p->errbuf, sizeof(p->errbuf), |
| 556 | "BIOCSETF: %s", pcap_strerror(errno)); |
| 557 | return (-1); |
| 558 | } |
| 559 | |
| 560 | /* |
| 561 | * OK, that succeeded. We're doing filtering in |
| 562 | * the kernel. (We assume we don't have a |
| 563 | * userland filter installed - that'd require |
| 564 | * a previous version check to have failed but |
| 565 | * this one to succeed.) |
| 566 | * |
| 567 | * XXX - this message should be supplied to the |
| 568 | * application as a warning of some sort, |
| 569 | * except that if it's a GUI application, it's |
| 570 | * not clear that it should be displayed in |
| 571 | * a window to annoy the user. |
| 572 | */ |
| 573 | fprintf(stderr, "tcpdump: Using kernel BPF filter\n"); |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 574 | pf->filtering_in_kernel = 1; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 575 | |
| 576 | /* |
| 577 | * Discard any previously-received packets, |
| 578 | * as they might have passed whatever filter |
| 579 | * was formerly in effect, but might not pass |
| 580 | * this filter (BIOCSETF discards packets buffered |
| 581 | * in the kernel, so you can lose packets in any |
| 582 | * case). |
| 583 | */ |
| 584 | p->cc = 0; |
| 585 | return (0); |
| 586 | } |
| 587 | |
| 588 | /* |
| 589 | * We can't use the kernel's BPF interpreter; don't give |
| 590 | * up, just log a message and be inefficient. |
| 591 | * |
| 592 | * XXX - this should really be supplied to the application |
| 593 | * as a warning of some sort. |
| 594 | */ |
| 595 | fprintf(stderr, |
| 596 | "tcpdump: Requires BPF language %d.%d or higher; kernel is %d.%d\n", |
| 597 | BPF_MAJOR_VERSION, BPF_MINOR_VERSION, |
| 598 | bv.bv_major, bv.bv_minor); |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * We couldn't do filtering in the kernel; do it in userland. |
| 603 | */ |
| 604 | if (install_bpf_program(p, fp) < 0) |
| 605 | return (-1); |
| 606 | |
| 607 | /* |
| 608 | * XXX - this message should be supplied by the application as |
| 609 | * a warning of some sort. |
| 610 | */ |
| 611 | fprintf(stderr, "tcpdump: Filtering in user process\n"); |
JP Abgrall | 511eca3 | 2014-02-12 13:46:45 -0800 | [diff] [blame] | 612 | pf->filtering_in_kernel = 0; |
The Android Open Source Project | 478ab6c | 2009-03-03 19:30:05 -0800 | [diff] [blame] | 613 | return (0); |
| 614 | } |