freebsd-dev/sys/net/bpf.h
Pedro F. Giffuni 51369649b0 sys: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:43:44 +00:00

476 lines
15 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1990, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from the Stanford/CMU enet packet filter,
* (net/enet.c) distributed as part of 4.3BSD, and code contributed
* to Berkeley by Steven McCanne and Van Jacobson both of Lawrence
* Berkeley Laboratory.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)bpf.h 8.1 (Berkeley) 6/10/93
* @(#)bpf.h 1.34 (LBL) 6/16/96
*
* $FreeBSD$
*/
#ifndef _NET_BPF_H_
#define _NET_BPF_H_
/* BSD style release date */
#define BPF_RELEASE 199606
typedef int32_t bpf_int32;
typedef u_int32_t bpf_u_int32;
typedef int64_t bpf_int64;
typedef u_int64_t bpf_u_int64;
/*
* Alignment macros. BPF_WORDALIGN rounds up to the next
* even multiple of BPF_ALIGNMENT.
*/
#define BPF_ALIGNMENT sizeof(long)
#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
#define BPF_MAXINSNS 512
#define BPF_MAXBUFSIZE 0x80000
#define BPF_MINBUFSIZE 32
/*
* Structure for BIOCSETF.
*/
struct bpf_program {
u_int bf_len;
struct bpf_insn *bf_insns;
};
/*
* Struct returned by BIOCGSTATS.
*/
struct bpf_stat {
u_int bs_recv; /* number of packets received */
u_int bs_drop; /* number of packets dropped */
};
/*
* Struct return by BIOCVERSION. This represents the version number of
* the filter language described by the instruction encodings below.
* bpf understands a program iff kernel_major == filter_major &&
* kernel_minor >= filter_minor, that is, if the value returned by the
* running kernel has the same major number and a minor number equal
* equal to or less than the filter being downloaded. Otherwise, the
* results are undefined, meaning an error may be returned or packets
* may be accepted haphazardly.
* It has nothing to do with the source code version.
*/
struct bpf_version {
u_short bv_major;
u_short bv_minor;
};
/* Current version number of filter architecture. */
#define BPF_MAJOR_VERSION 1
#define BPF_MINOR_VERSION 1
/*
* Historically, BPF has supported a single buffering model, first using mbuf
* clusters in kernel, and later using malloc(9) buffers in kernel. We now
* support multiple buffering modes, which may be queried and set using
* BIOCGETBUFMODE and BIOCSETBUFMODE. So as to avoid handling the complexity
* of changing modes while sniffing packets, the mode becomes fixed once an
* interface has been attached to the BPF descriptor.
*/
#define BPF_BUFMODE_BUFFER 1 /* Kernel buffers with read(). */
#define BPF_BUFMODE_ZBUF 2 /* Zero-copy buffers. */
/*-
* Struct used by BIOCSETZBUF, BIOCROTZBUF: describes up to two zero-copy
* buffer as used by BPF.
*/
struct bpf_zbuf {
void *bz_bufa; /* Location of 'a' zero-copy buffer. */
void *bz_bufb; /* Location of 'b' zero-copy buffer. */
size_t bz_buflen; /* Size of zero-copy buffers. */
};
#define BIOCGBLEN _IOR('B', 102, u_int)
#define BIOCSBLEN _IOWR('B', 102, u_int)
#define BIOCSETF _IOW('B', 103, struct bpf_program)
#define BIOCFLUSH _IO('B', 104)
#define BIOCPROMISC _IO('B', 105)
#define BIOCGDLT _IOR('B', 106, u_int)
#define BIOCGETIF _IOR('B', 107, struct ifreq)
#define BIOCSETIF _IOW('B', 108, struct ifreq)
#define BIOCSRTIMEOUT _IOW('B', 109, struct timeval)
#define BIOCGRTIMEOUT _IOR('B', 110, struct timeval)
#define BIOCGSTATS _IOR('B', 111, struct bpf_stat)
#define BIOCIMMEDIATE _IOW('B', 112, u_int)
#define BIOCVERSION _IOR('B', 113, struct bpf_version)
#define BIOCGRSIG _IOR('B', 114, u_int)
#define BIOCSRSIG _IOW('B', 115, u_int)
#define BIOCGHDRCMPLT _IOR('B', 116, u_int)
#define BIOCSHDRCMPLT _IOW('B', 117, u_int)
#define BIOCGDIRECTION _IOR('B', 118, u_int)
#define BIOCSDIRECTION _IOW('B', 119, u_int)
#define BIOCSDLT _IOW('B', 120, u_int)
#define BIOCGDLTLIST _IOWR('B', 121, struct bpf_dltlist)
#define BIOCLOCK _IO('B', 122)
#define BIOCSETWF _IOW('B', 123, struct bpf_program)
#define BIOCFEEDBACK _IOW('B', 124, u_int)
#define BIOCGETBUFMODE _IOR('B', 125, u_int)
#define BIOCSETBUFMODE _IOW('B', 126, u_int)
#define BIOCGETZMAX _IOR('B', 127, size_t)
#define BIOCROTZBUF _IOR('B', 128, struct bpf_zbuf)
#define BIOCSETZBUF _IOW('B', 129, struct bpf_zbuf)
#define BIOCSETFNR _IOW('B', 130, struct bpf_program)
#define BIOCGTSTAMP _IOR('B', 131, u_int)
#define BIOCSTSTAMP _IOW('B', 132, u_int)
/* Obsolete */
#define BIOCGSEESENT BIOCGDIRECTION
#define BIOCSSEESENT BIOCSDIRECTION
/* Packet directions */
enum bpf_direction {
BPF_D_IN, /* See incoming packets */
BPF_D_INOUT, /* See incoming and outgoing packets */
BPF_D_OUT /* See outgoing packets */
};
/* Time stamping functions */
#define BPF_T_MICROTIME 0x0000
#define BPF_T_NANOTIME 0x0001
#define BPF_T_BINTIME 0x0002
#define BPF_T_NONE 0x0003
#define BPF_T_FORMAT_MASK 0x0003
#define BPF_T_NORMAL 0x0000
#define BPF_T_FAST 0x0100
#define BPF_T_MONOTONIC 0x0200
#define BPF_T_MONOTONIC_FAST (BPF_T_FAST | BPF_T_MONOTONIC)
#define BPF_T_FLAG_MASK 0x0300
#define BPF_T_FORMAT(t) ((t) & BPF_T_FORMAT_MASK)
#define BPF_T_FLAG(t) ((t) & BPF_T_FLAG_MASK)
#define BPF_T_VALID(t) \
((t) == BPF_T_NONE || (BPF_T_FORMAT(t) != BPF_T_NONE && \
((t) & ~(BPF_T_FORMAT_MASK | BPF_T_FLAG_MASK)) == 0))
#define BPF_T_MICROTIME_FAST (BPF_T_MICROTIME | BPF_T_FAST)
#define BPF_T_NANOTIME_FAST (BPF_T_NANOTIME | BPF_T_FAST)
#define BPF_T_BINTIME_FAST (BPF_T_BINTIME | BPF_T_FAST)
#define BPF_T_MICROTIME_MONOTONIC (BPF_T_MICROTIME | BPF_T_MONOTONIC)
#define BPF_T_NANOTIME_MONOTONIC (BPF_T_NANOTIME | BPF_T_MONOTONIC)
#define BPF_T_BINTIME_MONOTONIC (BPF_T_BINTIME | BPF_T_MONOTONIC)
#define BPF_T_MICROTIME_MONOTONIC_FAST (BPF_T_MICROTIME | BPF_T_MONOTONIC_FAST)
#define BPF_T_NANOTIME_MONOTONIC_FAST (BPF_T_NANOTIME | BPF_T_MONOTONIC_FAST)
#define BPF_T_BINTIME_MONOTONIC_FAST (BPF_T_BINTIME | BPF_T_MONOTONIC_FAST)
/*
* Structure prepended to each packet.
*/
struct bpf_ts {
bpf_int64 bt_sec; /* seconds */
bpf_u_int64 bt_frac; /* fraction */
};
struct bpf_xhdr {
struct bpf_ts bh_tstamp; /* time stamp */
bpf_u_int32 bh_caplen; /* length of captured portion */
bpf_u_int32 bh_datalen; /* original length of packet */
u_short bh_hdrlen; /* length of bpf header (this struct
plus alignment padding) */
};
/* Obsolete */
struct bpf_hdr {
struct timeval bh_tstamp; /* time stamp */
bpf_u_int32 bh_caplen; /* length of captured portion */
bpf_u_int32 bh_datalen; /* original length of packet */
u_short bh_hdrlen; /* length of bpf header (this struct
plus alignment padding) */
};
#ifdef _KERNEL
#define MTAG_BPF 0x627066
#define MTAG_BPF_TIMESTAMP 0
#endif
/*
* When using zero-copy BPF buffers, a shared memory header is present
* allowing the kernel BPF implementation and user process to synchronize
* without using system calls. This structure defines that header. When
* accessing these fields, appropriate atomic operation and memory barriers
* are required in order not to see stale or out-of-order data; see bpf(4)
* for reference code to access these fields from userspace.
*
* The layout of this structure is critical, and must not be changed; if must
* fit in a single page on all architectures.
*/
struct bpf_zbuf_header {
volatile u_int bzh_kernel_gen; /* Kernel generation number. */
volatile u_int bzh_kernel_len; /* Length of data in the buffer. */
volatile u_int bzh_user_gen; /* User generation number. */
u_int _bzh_pad[5];
};
/* Pull in data-link level type codes. */
#include <net/dlt.h>
/*
* The instruction encodings.
*
* Please inform tcpdump-workers@lists.tcpdump.org if you use any
* of the reserved values, so that we can note that they're used
* (and perhaps implement it in the reference BPF implementation
* and encourage its implementation elsewhere).
*/
/*
* The upper 8 bits of the opcode aren't used. BSD/OS used 0x8000.
*/
/* instruction classes */
#define BPF_CLASS(code) ((code) & 0x07)
#define BPF_LD 0x00
#define BPF_LDX 0x01
#define BPF_ST 0x02
#define BPF_STX 0x03
#define BPF_ALU 0x04
#define BPF_JMP 0x05
#define BPF_RET 0x06
#define BPF_MISC 0x07
/* ld/ldx fields */
#define BPF_SIZE(code) ((code) & 0x18)
#define BPF_W 0x00
#define BPF_H 0x08
#define BPF_B 0x10
/* 0x18 reserved; used by BSD/OS */
#define BPF_MODE(code) ((code) & 0xe0)
#define BPF_IMM 0x00
#define BPF_ABS 0x20
#define BPF_IND 0x40
#define BPF_MEM 0x60
#define BPF_LEN 0x80
#define BPF_MSH 0xa0
/* 0xc0 reserved; used by BSD/OS */
/* 0xe0 reserved; used by BSD/OS */
/* alu/jmp fields */
#define BPF_OP(code) ((code) & 0xf0)
#define BPF_ADD 0x00
#define BPF_SUB 0x10
#define BPF_MUL 0x20
#define BPF_DIV 0x30
#define BPF_OR 0x40
#define BPF_AND 0x50
#define BPF_LSH 0x60
#define BPF_RSH 0x70
#define BPF_NEG 0x80
#define BPF_MOD 0x90
#define BPF_XOR 0xa0
/* 0xb0 reserved */
/* 0xc0 reserved */
/* 0xd0 reserved */
/* 0xe0 reserved */
/* 0xf0 reserved */
#define BPF_JA 0x00
#define BPF_JEQ 0x10
#define BPF_JGT 0x20
#define BPF_JGE 0x30
#define BPF_JSET 0x40
/* 0x50 reserved; used on BSD/OS */
/* 0x60 reserved */
/* 0x70 reserved */
/* 0x80 reserved */
/* 0x90 reserved */
/* 0xa0 reserved */
/* 0xb0 reserved */
/* 0xc0 reserved */
/* 0xd0 reserved */
/* 0xe0 reserved */
/* 0xf0 reserved */
#define BPF_SRC(code) ((code) & 0x08)
#define BPF_K 0x00
#define BPF_X 0x08
/* ret - BPF_K and BPF_X also apply */
#define BPF_RVAL(code) ((code) & 0x18)
#define BPF_A 0x10
/* 0x18 reserved */
/* misc */
#define BPF_MISCOP(code) ((code) & 0xf8)
#define BPF_TAX 0x00
/* 0x08 reserved */
/* 0x10 reserved */
/* 0x18 reserved */
/* #define BPF_COP 0x20 NetBSD "coprocessor" extensions */
/* 0x28 reserved */
/* 0x30 reserved */
/* 0x38 reserved */
/* #define BPF_COPX 0x40 NetBSD "coprocessor" extensions */
/* also used on BSD/OS */
/* 0x48 reserved */
/* 0x50 reserved */
/* 0x58 reserved */
/* 0x60 reserved */
/* 0x68 reserved */
/* 0x70 reserved */
/* 0x78 reserved */
#define BPF_TXA 0x80
/* 0x88 reserved */
/* 0x90 reserved */
/* 0x98 reserved */
/* 0xa0 reserved */
/* 0xa8 reserved */
/* 0xb0 reserved */
/* 0xb8 reserved */
/* 0xc0 reserved; used on BSD/OS */
/* 0xc8 reserved */
/* 0xd0 reserved */
/* 0xd8 reserved */
/* 0xe0 reserved */
/* 0xe8 reserved */
/* 0xf0 reserved */
/* 0xf8 reserved */
/*
* The instruction data structure.
*/
struct bpf_insn {
u_short code;
u_char jt;
u_char jf;
bpf_u_int32 k;
};
/*
* Macros for insn array initializers.
*/
#define BPF_STMT(code, k) { (u_short)(code), 0, 0, k }
#define BPF_JUMP(code, k, jt, jf) { (u_short)(code), jt, jf, k }
/*
* Structure to retrieve available DLTs for the interface.
*/
struct bpf_dltlist {
u_int bfl_len; /* number of bfd_list array */
u_int *bfl_list; /* array of DLTs */
};
#ifdef _KERNEL
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_BPF);
#endif
#ifdef SYSCTL_DECL
SYSCTL_DECL(_net_bpf);
#endif
/*
* Rotate the packet buffers in descriptor d. Move the store buffer into the
* hold slot, and the free buffer into the store slot. Zero the length of the
* new store buffer. Descriptor lock should be held. One must be careful to
* not rotate the buffers twice, i.e. if fbuf != NULL.
*/
#define ROTATE_BUFFERS(d) do { \
(d)->bd_hbuf = (d)->bd_sbuf; \
(d)->bd_hlen = (d)->bd_slen; \
(d)->bd_sbuf = (d)->bd_fbuf; \
(d)->bd_slen = 0; \
(d)->bd_fbuf = NULL; \
bpf_bufheld(d); \
} while (0)
/*
* Descriptor associated with each attached hardware interface.
* Part of this structure is exposed to external callers to speed up
* bpf_peers_present() calls.
*/
struct bpf_if;
struct bpf_if_ext {
LIST_ENTRY(bpf_if) bif_next; /* list of all interfaces */
LIST_HEAD(, bpf_d) bif_dlist; /* descriptor list */
};
void bpf_bufheld(struct bpf_d *d);
int bpf_validate(const struct bpf_insn *, int);
void bpf_tap(struct bpf_if *, u_char *, u_int);
void bpf_mtap(struct bpf_if *, struct mbuf *);
void bpf_mtap2(struct bpf_if *, void *, u_int, struct mbuf *);
void bpfattach(struct ifnet *, u_int, u_int);
void bpfattach2(struct ifnet *, u_int, u_int, struct bpf_if **);
void bpfdetach(struct ifnet *);
#ifdef VIMAGE
int bpf_get_bp_params(struct bpf_if *, u_int *, u_int *);
#endif
void bpfilterattach(int);
u_int bpf_filter(const struct bpf_insn *, u_char *, u_int, u_int);
static __inline int
bpf_peers_present(struct bpf_if *bpf)
{
struct bpf_if_ext *ext;
ext = (struct bpf_if_ext *)bpf;
if (!LIST_EMPTY(&ext->bif_dlist))
return (1);
return (0);
}
#define BPF_TAP(_ifp,_pkt,_pktlen) do { \
if (bpf_peers_present((_ifp)->if_bpf)) \
bpf_tap((_ifp)->if_bpf, (_pkt), (_pktlen)); \
} while (0)
#define BPF_MTAP(_ifp,_m) do { \
if (bpf_peers_present((_ifp)->if_bpf)) { \
M_ASSERTVALID(_m); \
bpf_mtap((_ifp)->if_bpf, (_m)); \
} \
} while (0)
#define BPF_MTAP2(_ifp,_data,_dlen,_m) do { \
if (bpf_peers_present((_ifp)->if_bpf)) { \
M_ASSERTVALID(_m); \
bpf_mtap2((_ifp)->if_bpf,(_data),(_dlen),(_m)); \
} \
} while (0)
#endif
/*
* Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
*/
#define BPF_MEMWORDS 16
#ifdef _SYS_EVENTHANDLER_H_
/* BPF attach/detach events */
struct ifnet;
typedef void (*bpf_track_fn)(void *, struct ifnet *, int /* dlt */,
int /* 1 =>'s attach */);
EVENTHANDLER_DECLARE(bpf_track, bpf_track_fn);
#endif /* _SYS_EVENTHANDLER_H_ */
#endif /* _NET_BPF_H_ */