/*      $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_ */