sys/net/bpf.h

   1 /*
   2  * Copyright (c) 1990, 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from the Stanford/CMU enet packet filter,
   6  * (net/enet.c) distributed as part of 4.3BSD, and code contributed
   7  * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
   8  * Berkeley Laboratory.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)bpf.h       8.1 (Berkeley) 6/10/93
  39  *      @(#)bpf.h       1.34 (LBL)     6/16/96
  40  *
  41  * $FreeBSD: src/sys/net/bpf.h,v 1.21.2.4 2002/07/05 14:40:00 fenner Exp $
  42  * $DragonFly: src/sys/net/bpf.h,v 1.11 2006/05/20 16:48:51 dillon Exp $
  43  */
  44
  45 #ifndef _NET_BPF_H_
  46 #define _NET_BPF_H_
  47
  48 #ifndef _SYS_TYPES_H_
  49 #include <sys/types.h>
  50 #endif
  51 #ifndef _SYS_TIME_H_
  52 #include <sys/time.h>
  53 #endif
  54
  55 /* BSD style release date */
  56 #define BPF_RELEASE 199606
  57
  58 typedef int32_t   bpf_int32;
  59 typedef u_int32_t bpf_u_int32;
  60
  61 /*
  62  * Alignment macros.  BPF_WORDALIGN rounds up to the next
  63  * even multiple of BPF_ALIGNMENT.
  64  */
  65 #define BPF_ALIGNMENT sizeof(long)
  66 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
  67
  68 #define BPF_MAXINSNS 512
  69 #define BPF_MAXBUFSIZE 0x80000
  70 #define BPF_DEFAULTBUFSIZE 4096
  71 #define BPF_MINBUFSIZE 32
  72
  73 /*
  74  *  Structure for BIOCSETF.
  75  */
  76 struct bpf_program {
  77         u_int bf_len;
  78         struct bpf_insn *bf_insns;
  79 };
  80
  81 /*
  82  * Struct returned by BIOCGSTATS.
  83  */
  84 struct bpf_stat {
  85         u_int bs_recv;          /* number of packets received */
  86         u_int bs_drop;          /* number of packets dropped */
  87 };
  88
  89 /*
  90  * Struct return by BIOCVERSION.  This represents the version number of
  91  * the filter language described by the instruction encodings below.
  92  * bpf understands a program iff kernel_major == filter_major &&
  93  * kernel_minor >= filter_minor, that is, if the value returned by the
  94  * running kernel has the same major number and a minor number equal
  95  * equal to or less than the filter being downloaded.  Otherwise, the
  96  * results are undefined, meaning an error may be returned or packets
  97  * may be accepted haphazardly.
  98  * It has nothing to do with the source code version.
  99  */
 100 struct bpf_version {
 101         u_short bv_major;
 102         u_short bv_minor;
 103 };
 104 /* Current version number of filter architecture. */
 105 #define BPF_MAJOR_VERSION 1
 106 #define BPF_MINOR_VERSION 1
 107
 108 #define BIOCGBLEN       _IOR('B',102, u_int)
 109 #define BIOCSBLEN       _IOWR('B',102, u_int)
 110 #define BIOCSETF        _IOW('B',103, struct bpf_program)
 111 #define BIOCFLUSH       _IO('B',104)
 112 #define BIOCPROMISC     _IO('B',105)
 113 #define BIOCGDLT        _IOR('B',106, u_int)
 114 #define BIOCGETIF       _IOR('B',107, struct ifreq)
 115 #define BIOCSETIF       _IOW('B',108, struct ifreq)
 116 #define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
 117 #define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
 118 #define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
 119 #define BIOCIMMEDIATE   _IOW('B',112, u_int)
 120 #define BIOCVERSION     _IOR('B',113, struct bpf_version)
 121 #define BIOCGRSIG       _IOR('B',114, u_int)
 122 #define BIOCSRSIG       _IOW('B',115, u_int)
 123 #define BIOCGHDRCMPLT   _IOR('B',116, u_int)
 124 #define BIOCSHDRCMPLT   _IOW('B',117, u_int)
 125 #define BIOCGSEESENT    _IOR('B',118, u_int)
 126 #define BIOCSSEESENT    _IOW('B',119, u_int)
 127 #define BIOCSDLT        _IOW('B',120, u_int)
 128 #define BIOCGDLTLIST    _IOWR('B',121, struct bpf_dltlist)
 129
 130 /*
 131  * Structure prepended to each packet.
 132  */
 133 struct bpf_hdr {
 134         struct timeval  bh_tstamp;      /* time stamp */
 135         bpf_u_int32     bh_caplen;      /* length of captured portion */
 136         bpf_u_int32     bh_datalen;     /* original length of packet */
 137         u_short         bh_hdrlen;      /* length of bpf header (this struct
 138                                            plus alignment padding) */
 139 };
 140 /*
 141  * Because the structure above is not a multiple of 4 bytes, some compilers
 142  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 143  * Only the kernel needs to know about it; applications use bh_hdrlen.
 144  */
 145 #ifdef _KERNEL
 146 #define SIZEOF_BPF_HDR  (sizeof(struct bpf_hdr) <= 20 ? 18 : \
 147     sizeof(struct bpf_hdr))
 148 #endif
 149
 150 /*
 151  * Data-link level type codes.
 152  */
 153 #define DLT_NULL        0       /* no link-layer encapsulation */
 154 #define DLT_EN10MB      1       /* Ethernet (10Mb) */
 155 #define DLT_EN3MB       2       /* Experimental Ethernet (3Mb) */
 156 #define DLT_AX25        3       /* Amateur Radio AX.25 */
 157 #define DLT_PRONET      4       /* Proteon ProNET Token Ring */
 158 #define DLT_CHAOS       5       /* Chaos */
 159 #define DLT_IEEE802     6       /* IEEE 802 Networks */
 160 #define DLT_ARCNET      7       /* ARCNET */
 161 #define DLT_SLIP        8       /* Serial Line IP */
 162 #define DLT_PPP         9       /* Point-to-point Protocol */
 163 #define DLT_FDDI        10      /* FDDI */
 164 #define DLT_ATM_RFC1483 11      /* LLC/SNAP encapsulated atm */
 165 #define DLT_RAW         12      /* raw IP */
 166
 167 /*
 168  * These are values from BSD/OS's "bpf.h".
 169  * These are not the same as the values from the traditional libpcap
 170  * "bpf.h"; however, these values shouldn't be generated by any
 171  * OS other than BSD/OS, so the correct values to use here are the
 172  * BSD/OS values.
 173  *
 174  * Platforms that have already assigned these values to other
 175  * DLT_ codes, however, should give these codes the values
 176  * from that platform, so that programs that use these codes will
 177  * continue to compile - even though they won't correctly read
 178  * files of these types.
 179  */
 180 #define DLT_SLIP_BSDOS  15      /* BSD/OS Serial Line IP */
 181 #define DLT_PPP_BSDOS   16      /* BSD/OS Point-to-point Protocol */
 182
 183 #define DLT_ATM_CLIP    19      /* Linux Classical-IP over ATM */
 184
 185 /*
 186  * These values are defined by NetBSD; other platforms should refrain from
 187  * using them for other purposes, so that NetBSD savefiles with link
 188  * types of 50 or 51 can be read as this type on all platforms.
 189  */
 190 #define DLT_PPP_SERIAL  50      /* PPP over serial with HDLC encapsulation */
 191 #define DLT_PPP_ETHER   51      /* PPP over Ethernet */
 192
 193 /*
 194  * This value was defined by libpcap 0.5; platforms that have defined
 195  * it with a different value should define it here with that value -
 196  * a link type of 104 in a save file will be mapped to DLT_C_HDLC,
 197  * whatever value that happens to be, so programs will correctly
 198  * handle files with that link type regardless of the value of
 199  * DLT_C_HDLC.
 200  *
 201  * The name DLT_C_HDLC was used by BSD/OS; we use that name for source
 202  * compatibility with programs written for BSD/OS.
 203  *
 204  * libpcap 0.5 defined it as DLT_CHDLC; we define DLT_CHDLC as well,
 205  * for source compatibility with programs written for libpcap 0.5.
 206  */
 207 #define DLT_C_HDLC      104     /* Cisco HDLC */
 208 #define DLT_CHDLC       DLT_C_HDLC
 209
 210 #define DLT_IEEE802_11  105     /* IEEE 802.11 wireless */
 211
 212 /*
 213  * Values between 106 and 107 are used in capture file headers as
 214  * link-layer types corresponding to DLT_ types that might differ
 215  * between platforms; don't use those values for new DLT_ new types.
 216  */
 217
 218 /*
 219  * OpenBSD DLT_LOOP, for loopback devices; it's like DLT_NULL, except
 220  * that the AF_ type in the link-layer header is in network byte order.
 221  *
 222  * OpenBSD defines it as 12, but that collides with DLT_RAW, so we
 223  * define it as 108 here.  If OpenBSD picks up this file, it should
 224  * define DLT_LOOP as 12 in its version, as per the comment above -
 225  * and should not use 108 as a DLT_ value.
 226  */
 227 #define DLT_LOOP        108
 228
 229 /*
 230  * Values between 109 and 112 are used in capture file headers as
 231  * link-layer types corresponding to DLT_ types that might differ
 232  * between platforms; don't use those values for new DLT_ new types.
 233  */
 234
 235 /*
 236  * This is for Linux cooked sockets.
 237  */
 238 #define DLT_LINUX_SLL   113
 239
 240 /*
 241  * Apple LocalTalk hardware.
 242  */
 243 #define DLT_LTALK       114
 244
 245 /*
 246  * Acorn Econet.
 247  */
 248 #define DLT_ECONET      115
 249
 250 /*
 251  * Reserved for use with OpenBSD ipfilter.
 252  */
 253 #define DLT_IPFILTER    116
 254
 255 /*
 256  * Reserved for use in capture-file headers as a link-layer type
 257  * corresponding to OpenBSD DLT_PFLOG; DLT_PFLOG is 17 in OpenBSD,
 258  * but that's DLT_LANE8023 in SuSE 6.3, so we can't use 17 for it
 259  * in capture-file headers.
 260  */
 261 #define DLT_PFLOG       117
 262
 263 /*
 264  * Registered for Cisco-internal use.
 265  */
 266 #define DLT_CISCO_IOS   118
 267
 268 /*
 269  * Reserved for 802.11 cards using the Prism II chips, with a link-layer
 270  * header including Prism monitor mode information plus an 802.11
 271  * header.
 272  */
 273 #define DLT_PRISM_HEADER        119
 274
 275 /*
 276  * Reserved for Aironet 802.11 cards, with an Aironet link-layer header
 277  * (see Doug Ambrisko's FreeBSD patches).
 278  */
 279 #define DLT_AIRONET_HEADER      120
 280
 281 /*
 282  * Reserved for use by OpenBSD's pfsync device.
 283  */
 284 #define DLT_PFSYNC      121
 285
 286 /*
 287  * The instruction encodings.
 288  */
 289 /* instruction classes */
 290 #define BPF_CLASS(code) ((code) & 0x07)
 291 #define         BPF_LD          0x00
 292 #define         BPF_LDX         0x01
 293 #define         BPF_ST          0x02
 294 #define         BPF_STX         0x03
 295 #define         BPF_ALU         0x04
 296 #define         BPF_JMP         0x05
 297 #define         BPF_RET         0x06
 298 #define         BPF_MISC        0x07
 299
 300 /* ld/ldx fields */
 301 #define BPF_SIZE(code)  ((code) & 0x18)
 302 #define         BPF_W           0x00
 303 #define         BPF_H           0x08
 304 #define         BPF_B           0x10
 305 #define BPF_MODE(code)  ((code) & 0xe0)
 306 #define         BPF_IMM         0x00
 307 #define         BPF_ABS         0x20
 308 #define         BPF_IND         0x40
 309 #define         BPF_MEM         0x60
 310 #define         BPF_LEN         0x80
 311 #define         BPF_MSH         0xa0
 312
 313 /* alu/jmp fields */
 314 #define BPF_OP(code)    ((code) & 0xf0)
 315 #define         BPF_ADD         0x00
 316 #define         BPF_SUB         0x10
 317 #define         BPF_MUL         0x20
 318 #define         BPF_DIV         0x30
 319 #define         BPF_OR          0x40
 320 #define         BPF_AND         0x50
 321 #define         BPF_LSH         0x60
 322 #define         BPF_RSH         0x70
 323 #define         BPF_NEG         0x80
 324 #define         BPF_JA          0x00
 325 #define         BPF_JEQ         0x10
 326 #define         BPF_JGT         0x20
 327 #define         BPF_JGE         0x30
 328 #define         BPF_JSET        0x40
 329 #define BPF_SRC(code)   ((code) & 0x08)
 330 #define         BPF_K           0x00
 331 #define         BPF_X           0x08
 332
 333 /* ret - BPF_K and BPF_X also apply */
 334 #define BPF_RVAL(code)  ((code) & 0x18)
 335 #define         BPF_A           0x10
 336
 337 /* misc */
 338 #define BPF_MISCOP(code) ((code) & 0xf8)
 339 #define         BPF_TAX         0x00
 340 #define         BPF_TXA         0x80
 341
 342 /*
 343  * The instruction data structure.
 344  */
 345 struct bpf_insn {
 346         u_short         code;
 347         u_char          jt;
 348         u_char          jf;
 349         bpf_u_int32     k;
 350 };
 351
 352 /*
 353  * Macros for insn array initializers.
 354  */
 355 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
 356 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
 357
 358 /*
 359  * Structure to retrieve available DLTs for the interface.
 360  */
 361 struct bpf_dltlist {
 362         u_int   bfl_len;        /* number of bfd_list array */
 363         u_int   *bfl_list;      /* array of DLTs */
 364 };
 365
 366 #ifdef _KERNEL
 367 struct bpf_if;
 368 struct ifnet;
 369 struct mbuf;
 370
 371 int      bpf_validate(const struct bpf_insn *, int);
 372 void     bpf_tap(struct bpf_if *, u_char *, u_int);
 373 void     bpf_mtap(struct bpf_if *, struct mbuf *);
 374 void     bpf_mtap_family(struct bpf_if *, struct mbuf *m, __uint8_t family);
 375 void     bpf_ptap(struct bpf_if *, struct mbuf *, const void *, u_int);
 376 void     bpfattach(struct ifnet *, u_int, u_int);
 377 void     bpfattach_dlt(struct ifnet *, u_int, u_int, struct bpf_if **);
 378 void     bpfdetach(struct ifnet *);
 379
 380 void     bpfilterattach(int);
 381 u_int    bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
 382
 383 #define BPF_TAP(_ifp,_pkt,_pktlen) do {                         \
 384         if ((_ifp)->if_bpf)                                     \
 385                 bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen));     \
 386 } while (0)
 387 #define BPF_MTAP(_ifp,_m) do {                                  \
 388         if ((_ifp)->if_bpf)                                     \
 389                 bpf_mtap((_ifp)->if_bpf, (_m));                 \
 390 } while (0)
 391 #endif
 392
 393 /*
 394  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 395  */
 396 #define BPF_MEMWORDS 16
 397
 398 #endif