/* $FreeBSD$ */
/* $NetBSD: pfil.h,v 1.22 2003/06/23 12:57:08 martin Exp $ */
/*-
* Copyright (c) 1996 Matthew R. Green
* All rights reserved.
*
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#ifndef _NET_PFIL_H_
#define _NET_PFIL_H_
#include <sys/systm.h>
#include <sys/queue.h>
#include <sys/_lock.h>
#include <sys/_mutex.h>
#include <sys/condvar.h> /* XXX */
struct mbuf;
struct ifnet;
struct inpcb;
/*
* The packet filter hooks are designed for anything to call them to
* possibly intercept the packet.
*/
struct packet_filter_hook {
TAILQ_ENTRY(packet_filter_hook) pfil_link;
int (*pfil_func)(void *, struct mbuf **, struct ifnet *, int, struct inpcb *);
void *pfil_arg;
int pfil_flags;
};
#define PFIL_IN 0x00000001
#define PFIL_OUT 0x00000002
#define PFIL_WAITOK 0x00000004
#define PFIL_ALL (PFIL_IN|PFIL_OUT)
typedef TAILQ_HEAD(pfil_list, packet_filter_hook) pfil_list_t;
#define PFIL_TYPE_AF 1 /* key is AF_* type */
#define PFIL_TYPE_IFNET 2 /* key is ifnet pointer */
struct pfil_head {
pfil_list_t ph_in;
pfil_list_t ph_out;
int ph_type;
/*
* Locking: use a busycounter per pfil_head.
* Use ph_busy_count = -1 to indicate pfil_head is empty.
*/
int ph_busy_count; /* count of threads with read lock */
int ph_want_write; /* want write lock flag */
struct cv ph_cv; /* for waking up writers */
struct mtx ph_mtx; /* mutex on locking state */
union {
u_long phu_val;
void *phu_ptr;
} ph_un;
#define ph_af ph_un.phu_val
#define ph_ifnet ph_un.phu_ptr
LIST_ENTRY(pfil_head) ph_list;
};
int pfil_run_hooks(struct pfil_head *, struct mbuf **, struct ifnet *,
int, struct inpcb *inp);
int pfil_add_hook(int (*func)(void *, struct mbuf **,
struct ifnet *, int, struct inpcb *), void *, int, struct pfil_head *);
int pfil_remove_hook(int (*func)(void *, struct mbuf **,
struct ifnet *, int, struct inpcb *), void *, int, struct pfil_head *);
int pfil_head_register(struct pfil_head *);
int pfil_head_unregister(struct pfil_head *);
struct pfil_head *pfil_head_get(int, u_long);
static __inline struct packet_filter_hook *
pfil_hook_get(int dir, struct pfil_head *ph)
{
KASSERT(ph->ph_busy_count > 0,
("pfil_hook_get: called on unbusy pfil_head"));
if (dir == PFIL_IN)
return (TAILQ_FIRST(&ph->ph_in));
else if (dir == PFIL_OUT)
return (TAILQ_FIRST(&ph->ph_out));
else
return (NULL);
}
#endif /* _NET_PFIL_H_ */
