NetBSD/sys/net/bpf.h

567 lines
16 KiB
C

/* $NetBSD: bpf.h,v 1.75 2020/06/11 13:36:20 roy Exp $ */
/*
* 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 8.2 (Berkeley) 1/9/95
* @(#) Header: bpf.h,v 1.36 97/06/12 14:29:53 leres Exp (LBL)
*/
#ifndef _NET_BPF_H_
#define _NET_BPF_H_
#include <sys/ioccom.h>
#include <sys/time.h>
/* BSD style release date */
#define BPF_RELEASE 199606
/* Date when COP instructions and external memory have been released. */
#define BPF_COP_EXTMEM_RELEASE 20140624
__BEGIN_DECLS
typedef int bpf_int32;
typedef u_int bpf_u_int32;
/*
* Alignment macros. BPF_WORDALIGN rounds up to the next
* even multiple of BPF_ALIGNMENT.
*/
#define BPF_ALIGNMENT sizeof(long)
#define BPF_ALIGNMENT32 sizeof(int)
#define BPF_WORDALIGN(x) (((x)+(BPF_ALIGNMENT-1))&~(BPF_ALIGNMENT-1))
#define BPF_WORDALIGN32(x) (((x)+(BPF_ALIGNMENT32-1))&~(BPF_ALIGNMENT32-1))
#define BPF_MAXINSNS 512
#define BPF_DFLTBUFSIZE (1024*1024) /* default static upper limit */
#define BPF_MAXBUFSIZE (1024*1024*16) /* hard limit on sysctl'able value */
#define BPF_MINBUFSIZE 32
/*
* Structure for BIOCSETF.
*/
struct bpf_program {
u_int bf_len;
struct bpf_insn *bf_insns;
};
/*
* Struct returned by BIOCGSTATS and net.bpf.stats sysctl.
*/
struct bpf_stat {
uint64_t bs_recv; /* number of packets received */
uint64_t bs_drop; /* number of packets dropped */
uint64_t bs_capt; /* number of packets captured */
uint64_t bs_padding[13];
};
/*
* Struct returned by BIOCGSTATSOLD.
*/
struct bpf_stat_old {
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
/*
* BPF ioctls
*
* The first set is for compatibility with Sun's pcc style
* header files. If your using gcc, we assume that you
* have run fixincludes so the latter set should work.
*/
#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)
#ifdef COMPAT_50
#include <compat/sys/time.h>
#define BIOCSORTIMEOUT _IOW('B', 109, struct timeval50)
#define BIOCGORTIMEOUT _IOR('B', 110, struct timeval50)
#endif
#define BIOCGSTATS _IOR('B', 111, struct bpf_stat)
#define BIOCGSTATSOLD _IOR('B', 111, struct bpf_stat_old)
#define BIOCIMMEDIATE _IOW('B', 112, u_int)
#define BIOCVERSION _IOR('B', 113, struct bpf_version)
#define BIOCSTCPF _IOW('B', 114, struct bpf_program)
#define BIOCSUDPF _IOW('B', 115, struct bpf_program)
#define BIOCGHDRCMPLT _IOR('B', 116, u_int)
#define BIOCSHDRCMPLT _IOW('B', 117, u_int)
#define BIOCSDLT _IOW('B', 118, u_int)
#define BIOCGDLTLIST _IOWR('B', 119, struct bpf_dltlist)
#define BIOCGDIRECTION _IOR('B', 120, u_int)
#define BIOCSDIRECTION _IOW('B', 121, u_int)
#define BIOCSRTIMEOUT _IOW('B', 122, struct timeval)
#define BIOCGRTIMEOUT _IOR('B', 123, struct timeval)
#define BIOCGFEEDBACK _IOR('B', 124, u_int)
#define BIOCSFEEDBACK _IOW('B', 125, u_int)
#define BIOCFEEDBACK BIOCSFEEDBACK /* FreeBSD name */
#define BIOCLOCK _IO('B', 126)
#define BIOCSETWF _IOW('B', 127, struct bpf_program)
/* Obsolete */
#define BIOCGSEESENT BIOCGDIRECTION
#define BIOCSSEESENT BIOCSDIRECTION
/*
* Packet directions.
* BPF_D_IN = 0, BPF_D_INOUT =1 for backward compatibility of BIOC[GS]SEESENT.
*/
#define BPF_D_IN 0 /* See incoming packets */
#define BPF_D_INOUT 1 /* See incoming and outgoing packets */
#define BPF_D_OUT 2 /* See outgoing packets */
/*
* Structure prepended to each packet. This is "wire" format, so we
* cannot change it unfortunately to 64 bit times on 32 bit systems [yet].
*/
struct bpf_timeval {
long tv_sec;
long tv_usec;
};
struct bpf_timeval32 {
int32_t tv_sec;
int32_t tv_usec;
};
struct bpf_hdr {
struct bpf_timeval bh_tstamp; /* time stamp */
uint32_t bh_caplen; /* length of captured portion */
uint32_t bh_datalen; /* original length of packet */
uint16_t bh_hdrlen; /* length of bpf header (this struct
plus alignment padding) */
};
struct bpf_hdr32 {
struct bpf_timeval32 bh_tstamp; /* time stamp */
uint32_t bh_caplen; /* length of captured portion */
uint32_t bh_datalen; /* original length of packet */
uint16_t bh_hdrlen; /* length of bpf header (this struct
plus alignment padding) */
};
/*
* Because the structure above is not a multiple of 4 bytes, some compilers
* will insist on inserting padding; hence, sizeof(struct bpf_hdr) won't work.
* Only the kernel needs to know about it; applications use bh_hdrlen.
* XXX To save a few bytes on 32-bit machines, we avoid end-of-struct
* XXX padding by using the size of the header data elements. This is
* XXX fail-safe: on new machines, we just use the 'safe' sizeof.
*/
#ifdef _KERNEL
#if defined(__arm32__) || defined(__i386__) || defined(__m68k__) || \
defined(__mips__) || defined(__ns32k__) || defined(__vax__) || \
defined(__sh__) || (defined(__sparc__) && !defined(__sparc64__))
#define SIZEOF_BPF_HDR 18
#define SIZEOF_BPF_HDR32 18
#else
#define SIZEOF_BPF_HDR sizeof(struct bpf_hdr)
#define SIZEOF_BPF_HDR32 sizeof(struct bpf_hdr32)
#endif
#endif
/* Pull in data-link level type codes. */
#include <net/dlt.h>
/*
* The instruction encodings.
*/
/* 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 by 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
/* 0x10 reserved */
/* 0x18 reserved */
#define BPF_COP 0x20
/* 0x28 reserved */
/* 0x30 reserved */
/* 0x38 reserved */
#define BPF_COPX 0x40 /* XXX: also used by 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 by BSD/OS */
/* 0xc8 reserved */
/* 0xd0 reserved */
/* 0xd8 reserved */
/* 0xe0 reserved */
/* 0xe8 reserved */
/* 0xf0 reserved */
/* 0xf8 reserved */
/*
* The instruction data structure.
*/
struct bpf_insn {
uint16_t code;
u_char jt;
u_char jf;
uint32_t k;
};
/*
* Auxiliary data, for use when interpreting a filter intended for the
* Linux kernel when the kernel rejects the filter (requiring us to
* run it in userland). It contains VLAN tag information.
*/
struct bpf_aux_data {
u_short vlan_tag_present;
u_short vlan_tag;
};
/*
* Macros for insn array initializers.
*/
#define BPF_STMT(code, k) { (uint16_t)(code), 0, 0, k }
#define BPF_JUMP(code, k, jt, jf) { (uint16_t)(code), jt, jf, k }
/*
* Number of scratch memory words (for BPF_LD|BPF_MEM and BPF_ST).
*/
#define BPF_MEMWORDS 16
/*
* bpf_memword_init_t: bits indicate which words in the external memory
* store will be initialised by the caller before BPF program execution.
*/
typedef uint32_t bpf_memword_init_t;
#define BPF_MEMWORD_INIT(k) (UINT32_C(1) << (k))
/* Note: two most significant bits are reserved by bpfjit. */
__CTASSERT(BPF_MEMWORDS + 2 <= sizeof(bpf_memword_init_t) * NBBY);
#ifdef _KERNEL
/*
* Max number of external memory words (for BPF_LD|BPF_MEM and BPF_ST).
*/
#define BPF_MAX_MEMWORDS 30
__CTASSERT(BPF_MAX_MEMWORDS >= BPF_MEMWORDS);
__CTASSERT(BPF_MAX_MEMWORDS + 2 <= sizeof(bpf_memword_init_t) * NBBY);
#endif
/*
* 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 */
};
struct bpf_ctx;
typedef struct bpf_ctx bpf_ctx_t;
typedef struct bpf_args {
const uint8_t * pkt;
size_t wirelen;
size_t buflen;
/*
* The following arguments are used only by some kernel
* subsystems.
* They aren't required for classical bpf filter programs.
* For such programs, bpfjit generated code doesn't read
* those arguments at all. Note however that bpf interpreter
* always needs a pointer to memstore.
*/
uint32_t * mem; /* pointer to external memory store */
void * arg; /* auxiliary argument for a copfunc */
} bpf_args_t;
#if defined(_KERNEL) || defined(__BPF_PRIVATE)
typedef uint32_t (*bpf_copfunc_t)(const bpf_ctx_t *, bpf_args_t *, uint32_t);
struct bpf_ctx {
/*
* BPF coprocessor functions and the number of them.
*/
const bpf_copfunc_t * copfuncs;
size_t nfuncs;
/*
* The number of memory words in the external memory store.
* There may be up to BPF_MAX_MEMWORDS words; if zero is set,
* then the internal memory store is used which has a fixed
* number of words (BPF_MEMWORDS).
*/
size_t extwords;
/*
* The bitmask indicating which words in the external memstore
* will be initialised by the caller.
*/
bpf_memword_init_t preinited;
};
#endif
#ifdef _KERNEL
#include <net/bpfjit.h>
#include <net/if.h>
struct bpf_if;
struct bpf_ops {
void (*bpf_attach)(struct ifnet *, u_int, u_int, struct bpf_if **);
void (*bpf_detach)(struct ifnet *);
void (*bpf_change_type)(struct ifnet *, u_int, u_int);
void (*bpf_mtap)(struct bpf_if *, struct mbuf *, u_int);
void (*bpf_mtap2)(struct bpf_if *, void *, u_int, struct mbuf *,
u_int);
void (*bpf_mtap_af)(struct bpf_if *, uint32_t, struct mbuf *, u_int);
void (*bpf_mtap_sl_in)(struct bpf_if *, u_char *, struct mbuf **);
void (*bpf_mtap_sl_out)(struct bpf_if *, u_char *, struct mbuf *);
void (*bpf_mtap_softint_init)(struct ifnet *);
void (*bpf_mtap_softint)(struct ifnet *, struct mbuf *);
};
extern struct bpf_ops *bpf_ops;
static __inline void
bpf_attach(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen)
{
bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, &_ifp->if_bpf);
}
static __inline void
bpf_attach2(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen, struct bpf_if **_dp)
{
bpf_ops->bpf_attach(_ifp, _dlt, _hdrlen, _dp);
}
static __inline void
bpf_mtap(struct ifnet *_ifp, struct mbuf *_m, u_int _direction)
{
if (_ifp->if_bpf)
bpf_ops->bpf_mtap(_ifp->if_bpf, _m, _direction);
}
static __inline void
bpf_mtap2(struct bpf_if *_bpf, void *_data, u_int _dlen, struct mbuf *_m,
u_int _direction)
{
bpf_ops->bpf_mtap2(_bpf, _data, _dlen, _m, _direction);
}
static __inline void
bpf_mtap3(struct bpf_if *_bpf, struct mbuf *_m, u_int _direction)
{
if (_bpf)
bpf_ops->bpf_mtap(_bpf, _m, _direction);
}
static __inline void
bpf_mtap_af(struct ifnet *_ifp, uint32_t _af, struct mbuf *_m,
u_int _direction)
{
if (_ifp->if_bpf)
bpf_ops->bpf_mtap_af(_ifp->if_bpf, _af, _m, _direction);
}
static __inline void
bpf_change_type(struct ifnet *_ifp, u_int _dlt, u_int _hdrlen)
{
bpf_ops->bpf_change_type(_ifp, _dlt, _hdrlen);
}
static __inline void
bpf_detach(struct ifnet *_ifp)
{
bpf_ops->bpf_detach(_ifp);
}
static __inline void
bpf_mtap_sl_in(struct ifnet *_ifp, u_char *_hdr, struct mbuf **_m)
{
bpf_ops->bpf_mtap_sl_in(_ifp->if_bpf, _hdr, _m);
}
static __inline void
bpf_mtap_sl_out(struct ifnet *_ifp, u_char *_hdr, struct mbuf *_m)
{
if (_ifp->if_bpf)
bpf_ops->bpf_mtap_sl_out(_ifp->if_bpf, _hdr, _m);
}
static __inline void
bpf_mtap_softint_init(struct ifnet *_ifp)
{
bpf_ops->bpf_mtap_softint_init(_ifp);
}
static __inline void
bpf_mtap_softint(struct ifnet *_ifp, struct mbuf *_m)
{
if (_ifp->if_bpf)
bpf_ops->bpf_mtap_softint(_ifp, _m);
}
void bpf_setops(void);
void bpf_ops_handover_enter(struct bpf_ops *);
void bpf_ops_handover_exit(void);
void bpfilterattach(int);
bpf_ctx_t *bpf_create(void);
void bpf_destroy(bpf_ctx_t *);
int bpf_set_cop(bpf_ctx_t *, const bpf_copfunc_t *, size_t);
int bpf_set_extmem(bpf_ctx_t *, size_t, bpf_memword_init_t);
u_int bpf_filter_ext(const bpf_ctx_t *, const struct bpf_insn *, bpf_args_t *);
int bpf_validate_ext(const bpf_ctx_t *, const struct bpf_insn *, int);
bpfjit_func_t bpf_jit_generate(bpf_ctx_t *, void *, size_t);
void bpf_jit_freecode(bpfjit_func_t);
#endif
int bpf_validate(const struct bpf_insn *, int);
u_int bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);
u_int bpf_filter_with_aux_data(const struct bpf_insn *, const u_char *, u_int, u_int, const struct bpf_aux_data *);
__END_DECLS
#endif /* !_NET_BPF_H_ */