bsd/net/bpf.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1990, 1991, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * This code is derived from the Stanford/CMU enet packet filter,
  27  * (net/enet.c) distributed as part of 4.3BSD, and code contributed
  28  * to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
  29  * Berkeley Laboratory.
  30  *
  31  * Redistribution and use in source and binary forms, with or without
  32  * modification, are permitted provided that the following conditions
  33  * are met:
  34  * 1. Redistributions of source code must retain the above copyright
  35  *    notice, this list of conditions and the following disclaimer.
  36  * 2. Redistributions in binary form must reproduce the above copyright
  37  *    notice, this list of conditions and the following disclaimer in the
  38  *    documentation and/or other materials provided with the distribution.
  39  * 3. All advertising materials mentioning features or use of this software
  40  *    must display the following acknowledgement:
  41  *      This product includes software developed by the University of
  42  *      California, Berkeley and its contributors.
  43  * 4. Neither the name of the University nor the names of its contributors
  44  *    may be used to endorse or promote products derived from this software
  45  *    without specific prior written permission.
  46  *
  47  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  48  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  49  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  50  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  51  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  52  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  53  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  54  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  55  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  56  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  57  * SUCH DAMAGE.
  58  *
  59  *      @(#)bpf.h       8.1 (Berkeley) 6/10/93
  60  *      @(#)bpf.h       1.34 (LBL)     6/16/96
  61  *
  62  * $FreeBSD: src/sys/net/bpf.h,v 1.21.2.3 2001/08/01 00:23:13 fenner Exp $
  63  */
  64
  65 #ifndef _NET_BPF_H_
  66 #define _NET_BPF_H_
  67 #include <sys/appleapiopts.h>
  68 #include <sys/types.h>
  69 #include <sys/time.h>
  70
  71 /* BSD style release date */
  72 #define BPF_RELEASE 199606
  73
  74 typedef int32_t   bpf_int32;
  75 typedef u_int32_t bpf_u_int32;
  76
  77 /*
  78  * Alignment macros.  BPF_WORDALIGN rounds up to the next
  79  * even multiple of BPF_ALIGNMENT.
  80  */
  81 #define BPF_ALIGNMENT sizeof(long)
  82 #define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
  83
  84 #define BPF_MAXINSNS 512
  85 #define BPF_MAXBUFSIZE 0x8000
  86 #define BPF_MINBUFSIZE 32
  87
  88 /*
  89  *  Structure for BIOCSETF.
  90  */
  91 struct bpf_program {
  92         u_int bf_len;
  93         struct bpf_insn *bf_insns;
  94 };
  95
  96 /*
  97  * Struct returned by BIOCGSTATS.
  98  */
  99 struct bpf_stat {
 100         u_int bs_recv;          /* number of packets received */
 101         u_int bs_drop;          /* number of packets dropped */
 102 };
 103
 104 /*
 105  * Struct return by BIOCVERSION.  This represents the version number of
 106  * the filter language described by the instruction encodings below.
 107  * bpf understands a program iff kernel_major == filter_major &&
 108  * kernel_minor >= filter_minor, that is, if the value returned by the
 109  * running kernel has the same major number and a minor number equal
 110  * equal to or less than the filter being downloaded.  Otherwise, the
 111  * results are undefined, meaning an error may be returned or packets
 112  * may be accepted haphazardly.
 113  * It has nothing to do with the source code version.
 114  */
 115 struct bpf_version {
 116         u_short bv_major;
 117         u_short bv_minor;
 118 };
 119 /* Current version number of filter architecture. */
 120 #define BPF_MAJOR_VERSION 1
 121 #define BPF_MINOR_VERSION 1
 122
 123 #define BIOCGBLEN       _IOR('B',102, u_int)
 124 #define BIOCSBLEN       _IOWR('B',102, u_int)
 125 #define BIOCSETF        _IOW('B',103, struct bpf_program)
 126 #define BIOCFLUSH       _IO('B',104)
 127 #define BIOCPROMISC     _IO('B',105)
 128 #define BIOCGDLT        _IOR('B',106, u_int)
 129 #define BIOCGETIF       _IOR('B',107, struct ifreq)
 130 #define BIOCSETIF       _IOW('B',108, struct ifreq)
 131 #define BIOCSRTIMEOUT   _IOW('B',109, struct timeval)
 132 #define BIOCGRTIMEOUT   _IOR('B',110, struct timeval)
 133 #define BIOCGSTATS      _IOR('B',111, struct bpf_stat)
 134 #define BIOCIMMEDIATE   _IOW('B',112, u_int)
 135 #define BIOCVERSION     _IOR('B',113, struct bpf_version)
 136 #define BIOCGRSIG       _IOR('B',114, u_int)
 137 #define BIOCSRSIG       _IOW('B',115, u_int)
 138 #define BIOCGHDRCMPLT   _IOR('B',116, u_int)
 139 #define BIOCSHDRCMPLT   _IOW('B',117, u_int)
 140 #define BIOCGSEESENT    _IOR('B',118, u_int)
 141 #define BIOCSSEESENT    _IOW('B',119, u_int)
 142
 143 /*
 144  * Structure prepended to each packet.
 145  */
 146 struct bpf_hdr {
 147         struct timeval  bh_tstamp;      /* time stamp */
 148         bpf_u_int32     bh_caplen;      /* length of captured portion */
 149         bpf_u_int32     bh_datalen;     /* original length of packet */
 150         u_short         bh_hdrlen;      /* length of bpf header (this struct
 151                                            plus alignment padding) */
 152 };
 153 /*
 154  * Because the structure above is not a multiple of 4 bytes, some compilers
 155  * will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
 156  * Only the kernel needs to know about it; applications use bh_hdrlen.
 157  */
 158 #ifdef KERNEL
 159 #define SIZEOF_BPF_HDR  (sizeof(struct bpf_hdr) <= 20 ? 18 : \
 160     sizeof(struct bpf_hdr))
 161 #endif
 162
 163 /*
 164  * Data-link level type codes.
 165  */
 166 #define DLT_NULL        0       /* no link-layer encapsulation */
 167 #define DLT_EN10MB      1       /* Ethernet (10Mb) */
 168 #define DLT_EN3MB       2       /* Experimental Ethernet (3Mb) */
 169 #define DLT_AX25        3       /* Amateur Radio AX.25 */
 170 #define DLT_PRONET      4       /* Proteon ProNET Token Ring */
 171 #define DLT_CHAOS       5       /* Chaos */
 172 #define DLT_IEEE802     6       /* IEEE 802 Networks */
 173 #define DLT_ARCNET      7       /* ARCNET */
 174 #define DLT_SLIP        8       /* Serial Line IP */
 175 #define DLT_PPP         9       /* Point-to-point Protocol */
 176 #define DLT_FDDI        10      /* FDDI */
 177 #define DLT_ATM_RFC1483 11      /* LLC/SNAP encapsulated atm */
 178 #define DLT_RAW         12      /* raw IP */
 179
 180 /*
 181  * These are values from BSD/OS's "bpf.h".
 182  * These are not the same as the values from the traditional libpcap
 183  * "bpf.h"; however, these values shouldn't be generated by any
 184  * OS other than BSD/OS, so the correct values to use here are the
 185  * BSD/OS values.
 186  *
 187  * Platforms that have already assigned these values to other
 188  * DLT_ codes, however, should give these codes the values
 189  * from that platform, so that programs that use these codes will
 190  * continue to compile - even though they won't correctly read
 191  * files of these types.
 192  */
 193 #define DLT_SLIP_BSDOS  15      /* BSD/OS Serial Line IP */
 194 #define DLT_PPP_BSDOS   16      /* BSD/OS Point-to-point Protocol */
 195
 196 #define DLT_ATM_CLIP    19      /* Linux Classical-IP over ATM */
 197
 198 /*
 199  * This value is defined by NetBSD; other platforms should refrain from
 200  * using it for other purposes, so that NetBSD savefiles with a link
 201  * type of 50 can be read as this type on all platforms.
 202  */
 203 #define DLT_PPP_SERIAL  50      /* PPP over serial with HDLC encapsulation */
 204
 205 /*
 206  * This value was defined by libpcap 0.5; platforms that have defined
 207  * it with a different value should define it here with that value -
 208  * a link type of 104 in a save file will be mapped to DLT_C_HDLC,
 209  * whatever value that happens to be, so programs will correctly
 210  * handle files with that link type regardless of the value of
 211  * DLT_C_HDLC.
 212  *
 213  * The name DLT_C_HDLC was used by BSD/OS; we use that name for source
 214  * compatibility with programs written for BSD/OS.
 215  *
 216  * libpcap 0.5 defined it as DLT_CHDLC; we define DLT_CHDLC as well,
 217  * for source compatibility with programs written for libpcap 0.5.
 218  */
 219 #define DLT_C_HDLC      104     /* Cisco HDLC */
 220 #define DLT_CHDLC       DLT_C_HDLC
 221
 222 /*
 223  * Reserved for future use.
 224  * Do not pick other numerical value for these unless you have also
 225  * picked up the tcpdump.org top-of-CVS-tree version of "savefile.c",
 226  * which will arrange that capture files for these DLT_ types have
 227  * the same "network" value on all platforms, regardless of what
 228  * value is chosen for their DLT_ type (thus allowing captures made
 229  * on one platform to be read on other platforms, even if the two
 230  * platforms don't use the same numerical values for all DLT_ types).
 231  */
 232 #define DLT_IEEE802_11  105     /* IEEE 802.11 wireless */
 233
 234 /*
 235  * Values between 106 and 107 are used in capture file headers as
 236  * link-layer types corresponding to DLT_ types that might differ
 237  * between platforms; don't use those values for new DLT_ new types.
 238  */
 239
 240 /*
 241  * OpenBSD DLT_LOOP, for loopback devices; it's like DLT_NULL, except
 242  * that the AF_ type in the link-layer header is in network byte order.
 243  *
 244  * OpenBSD defines it as 12, but that collides with DLT_RAW, so we
 245  * define it as 108 here.  If OpenBSD picks up this file, it should
 246  * define DLT_LOOP as 12 in its version, as per the comment above -
 247  * and should not use 108 for any purpose.
 248  */
 249 #define DLT_LOOP        108
 250
 251 /*
 252  * Values between 109 and 112 are used in capture file headers as
 253  * link-layer types corresponding to DLT_ types that might differ
 254  * between platforms; don't use those values for new DLT_ new types.
 255  */
 256
 257 /*
 258  * This is for Linux cooked sockets.
 259  */
 260 #define DLT_LINUX_SLL   113
 261
 262 /*
 263  * The instruction encodings.
 264  */
 265 /* instruction classes */
 266 #define BPF_CLASS(code) ((code) & 0x07)
 267 #define         BPF_LD          0x00
 268 #define         BPF_LDX         0x01
 269 #define         BPF_ST          0x02
 270 #define         BPF_STX         0x03
 271 #define         BPF_ALU         0x04
 272 #define         BPF_JMP         0x05
 273 #define         BPF_RET         0x06
 274 #define         BPF_MISC        0x07
 275
 276 /* ld/ldx fields */
 277 #define BPF_SIZE(code)  ((code) & 0x18)
 278 #define         BPF_W           0x00
 279 #define         BPF_H           0x08
 280 #define         BPF_B           0x10
 281 #define BPF_MODE(code)  ((code) & 0xe0)
 282 #define         BPF_IMM         0x00
 283 #define         BPF_ABS         0x20
 284 #define         BPF_IND         0x40
 285 #define         BPF_MEM         0x60
 286 #define         BPF_LEN         0x80
 287 #define         BPF_MSH         0xa0
 288
 289 /* alu/jmp fields */
 290 #define BPF_OP(code)    ((code) & 0xf0)
 291 #define         BPF_ADD         0x00
 292 #define         BPF_SUB         0x10
 293 #define         BPF_MUL         0x20
 294 #define         BPF_DIV         0x30
 295 #define         BPF_OR          0x40
 296 #define         BPF_AND         0x50
 297 #define         BPF_LSH         0x60
 298 #define         BPF_RSH         0x70
 299 #define         BPF_NEG         0x80
 300 #define         BPF_JA          0x00
 301 #define         BPF_JEQ         0x10
 302 #define         BPF_JGT         0x20
 303 #define         BPF_JGE         0x30
 304 #define         BPF_JSET        0x40
 305 #define BPF_SRC(code)   ((code) & 0x08)
 306 #define         BPF_K           0x00
 307 #define         BPF_X           0x08
 308
 309 /* ret - BPF_K and BPF_X also apply */
 310 #define BPF_RVAL(code)  ((code) & 0x18)
 311 #define         BPF_A           0x10
 312
 313 /* misc */
 314 #define BPF_MISCOP(code) ((code) & 0xf8)
 315 #define         BPF_TAX         0x00
 316 #define         BPF_TXA         0x80
 317
 318 /*
 319  * The instruction data structure.
 320  */
 321 struct bpf_insn {
 322         u_short         code;
 323         u_char          jt;
 324         u_char          jf;
 325         bpf_u_int32     k;
 326 };
 327
 328 /*
 329  * Macros for insn array initializers.
 330  */
 331 #define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
 332 #define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
 333
 334 /* Forward declerations */
 335 struct ifnet;
 336 struct mbuf;
 337
 338 #ifdef KERNEL
 339 #ifdef __APPLE_API_UNSTABLE
 340 int      bpf_validate __P((const struct bpf_insn *, int));
 341 void     bpf_tap __P((struct ifnet *, u_char *, u_int));
 342 void     bpf_mtap __P((struct ifnet *, struct mbuf *));
 343 void     bpfattach __P((struct ifnet *, u_int, u_int));
 344 void     bpfdetach __P((struct ifnet *));
 345
 346 void     bpfilterattach __P((int));
 347 u_int    bpf_filter __P((const struct bpf_insn *, u_char *, u_int, u_int));
 348
 349 #ifdef __APPLE__
 350 #define BPF_TAP(x, y, z) bpf_tap(x,y,z)
 351 #define BPF_MTAP(x, y) bpf_mtap(x, y)
 352 #endif /* __APPLE__ */
 353 #endif /* __APPLE_API_UNSTABLE */
 354 #endif /* KERNEL */
 355
 356 /*
 357  * Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
 358  */
 359 #define BPF_MEMWORDS 16
 360
 361 #endif