xref: /openbsd-src/sys/net/bpfdesc.h (revision 1511e544c2133eb425911df1402f18e15bb5ab0c)

/*	$OpenBSD: bpfdesc.h,v 1.50 2024/11/19 23:26:35 dlg Exp $	*/
/*	$NetBSD: bpfdesc.h,v 1.11 1995/09/27 18:30:42 thorpej 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.
 *
 *	@(#)bpfdesc.h	8.1 (Berkeley) 6/10/93
 */

#ifndef _NET_BPFDESC_H_
#define _NET_BPFDESC_H_

#ifdef _KERNEL

/*
 * Locks used to protect struct members in this file:
 *
 *	m	the per-descriptor mutex (bpf_d.bd_mtx)
 */

struct bpf_program_smr {
	struct bpf_program	bps_bf;
	struct smr_entry	bps_smr;
};

/*
 * Descriptor associated with each open bpf file.
 */
struct bpf_d {
	SMR_SLIST_ENTRY(bpf_d) bd_next;	/* Linked list of descriptors */
	/*
	 * Buffer slots: two mbuf clusters buffer the incoming packets.
	 *   The model has three slots.  Sbuf is always occupied.
	 *   sbuf (store) - Receive interrupt puts packets here.
	 *   hbuf (hold) - When sbuf is full, put cluster here and
	 *                 wakeup read (replace sbuf with fbuf).
	 *   fbuf (free) - When read is done, put cluster here.
	 * On receiving, if sbuf is full and fbuf is 0, packet is dropped.
	 */
	struct mutex	bd_mtx;		/* protect buffer slots below */
	caddr_t		bd_sbuf;	/* store slot */
	caddr_t		bd_hbuf;	/* hold slot */
	caddr_t		bd_fbuf;	/* free slot */
	int		bd_slen;	/* current length of store buffer */
	int		bd_hlen;	/* current length of hold buffer */
	int		bd_bufsize;	/* absolute length of buffers */

	int		bd_in_uiomove;	/* for debugging purpose */

	struct bpf_if  *bd_bif;		/* interface descriptor */
	uint64_t	bd_rtout;	/* [m] Read timeout in nanoseconds */
	uint64_t	bd_wtout;	/* [m] Wait time in nanoseconds */
	u_long		bd_nreaders;	/* [m] # threads asleep in bpfread() */
	struct bpf_program_smr
		       *bd_rfilter;	/* read filter code */
	struct bpf_program_smr
		       *bd_wfilter;	/* write filter code */
	u_long		bd_rcount;	/* number of packets received */
	u_long		bd_dcount;	/* number of packets dropped */

	u_char		bd_promisc;	/* true if listening promiscuously */
	u_char		bd_state;	/* [m] idle, waiting, or timed out */
	u_char		bd_locked;	/* true if descriptor is locked */
	u_char		bd_fildrop;	/* true if filtered packets will be dropped */
	u_char		bd_dirfilt;	/* direction filter */
	int		bd_hdrcmplt;	/* false to fill in src lladdr automatically */
	int		bd_async;	/* non-zero if packet reception should generate signal */
	int		bd_sig;		/* signal to send upon packet reception */
	struct sigio_ref
			bd_sigio;	/* async I/O registration */
	struct refcnt	bd_refcnt;	/* reference count */
	struct klist	bd_klist;	/* list of knotes */
	int		bd_unit;	/* logical unit number */
	LIST_ENTRY(bpf_d) bd_list;	/* descriptor list */

	struct task	bd_wake_task;	/* defer pgsigio() and selwakeup() */
	struct timeout	bd_wait_tmo;	/* delay wakeup after catching pkt */

	struct smr_entry
			bd_smr;
};

/*
 * Descriptor associated with each attached hardware interface.
 */
struct bpf_if {
	TAILQ_ENTRY(bpf_if) bif_next;	/* list of all interfaces */
	SMR_SLIST_HEAD(, bpf_d) bif_dlist;		/* descriptor list */
	struct bpf_if **bif_driverp;	/* pointer into softc */
	u_int bif_dlt;			/* link layer type */
	u_int bif_hdrlen;		/* length of header (with padding) */
	const char *bif_name;		/* name of "subsystem" */
	struct ifnet *bif_ifp;		/* corresponding interface */
};

int	 bpf_setf(struct bpf_d *, struct bpf_program *, u_long);
#endif /* _KERNEL */
#endif /* _NET_BPFDESC_H_ */