freebsd-skq/sys/net/bpfdesc.h
Robert Watson 2418d3ccec Modify BPF descriptor assertions to assert Giant when a BPF descriptor
lock is asserted and running non-MPSAFE.
2004-03-29 00:33:39 +00:00

133 lines
5.3 KiB
C

/*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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
*
* $FreeBSD$
*/
#ifndef _NET_BPFDESC_H_
#define _NET_BPFDESC_H_
#include <sys/callout.h>
#include <sys/selinfo.h>
/*
* Descriptor associated with each open bpf file.
*/
struct bpf_d {
struct 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.
*/
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 */
struct bpf_if * bd_bif; /* interface descriptor */
u_long bd_rtout; /* Read timeout in 'ticks' */
struct bpf_insn *bd_filter; /* 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; /* idle, waiting, or timed out */
u_char bd_immediate; /* true to return on packet arrival */
int bd_hdrcmplt; /* false to fill in src lladdr automatically */
int bd_seesent; /* true if bpf should see sent packets */
int bd_async; /* non-zero if packet reception should generate signal */
int bd_sig; /* signal to send upon packet reception */
struct sigio * bd_sigio; /* information for async I/O */
#if BSD < 199103
u_char bd_selcoll; /* true if selects collide */
int bd_timedout;
struct thread * bd_selthread; /* process that last selected us */
#else
u_char bd_pad; /* explicit alignment */
struct selinfo bd_sel; /* bsd select info */
#endif
struct mtx bd_mtx; /* mutex for this descriptor */
struct callout bd_callout; /* for BPF timeouts with select */
struct label *bd_label; /* MAC label for descriptor */
};
/* Values for bd_state */
#define BPF_IDLE 0 /* no select in progress */
#define BPF_WAITING 1 /* waiting for read timeout in select */
#define BPF_TIMED_OUT 2 /* read timeout has expired in select */
#define BPFD_LOCK(bd) mtx_lock(&(bd)->bd_mtx)
#define BPFD_UNLOCK(bd) mtx_unlock(&(bd)->bd_mtx)
#define BPFD_LOCK_ASSERT(bd) do { \
mtx_assert(&(bd)->bd_mtx, MA_OWNED); \
NET_ASSERT_GIANT(); \
} while (0)
/* Test whether a BPF is ready for read(). */
#define bpf_ready(bd) \
((bd)->bd_hlen != 0 || \
(((bd)->bd_immediate || (bd)->bd_state == BPF_TIMED_OUT) && \
(bd)->bd_slen != 0))
/*
* Descriptor associated with each attached hardware interface.
*/
struct bpf_if {
struct bpf_if *bif_next; /* list of all interfaces */
struct 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) */
struct ifnet *bif_ifp; /* corresponding interface */
struct mtx bif_mtx; /* mutex for interface */
};
#define BPFIF_LOCK(bif) mtx_lock(&(bif)->bif_mtx)
#define BPFIF_UNLOCK(bif) mtx_unlock(&(bif)->bif_mtx)
#endif