2 /* $NetBSD: pfil.h,v 1.22 2003/06/23 12:57:08 martin Exp $ */
5 * SPDX-License-Identifier: BSD-3-Clause
7 * Copyright (c) 1996 Matthew R. Green
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 #include <sys/systm.h>
38 #include <sys/queue.h>
39 #include <sys/_lock.h>
40 #include <sys/_mutex.h>
42 #include <sys/rmlock.h>
49 typedef int (*pfil_func_t)(void *, struct mbuf **, struct ifnet *, int,
53 * The packet filter hooks are designed for anything to call them to
54 * possibly intercept the packet. Multiple filter hooks are chained
55 * together and after each other in the specified order.
57 struct packet_filter_hook {
58 TAILQ_ENTRY(packet_filter_hook) pfil_chain;
59 pfil_func_t pfil_func;
63 #define PFIL_IN 0x00000001
64 #define PFIL_OUT 0x00000002
65 #define PFIL_WAITOK 0x00000004
66 #define PFIL_ALL (PFIL_IN|PFIL_OUT)
68 typedef TAILQ_HEAD(pfil_chain, packet_filter_hook) pfil_chain_t;
70 #define PFIL_TYPE_AF 1 /* key is AF_* type */
71 #define PFIL_TYPE_IFNET 2 /* key is ifnet pointer */
73 #define PFIL_FLAG_PRIVATE_LOCK 0x01 /* Personal lock instead of global */
76 * A pfil head is created by each protocol or packet intercept point.
77 * For packet is then run through the hook chain for inspection.
84 #if defined( __linux__ ) || defined( _WIN32 )
87 struct rmlock *ph_plock; /* Pointer to the used lock */
88 struct rmlock ph_lock; /* Private lock storage */
95 #define ph_af ph_un.phu_val
96 #define ph_ifnet ph_un.phu_ptr
97 LIST_ENTRY(pfil_head) ph_list;
100 VNET_DECLARE(struct rmlock, pfil_lock);
101 #define V_pfil_lock VNET(pfil_lock)
103 /* Public functions for pfil hook management by packet filters. */
104 struct pfil_head *pfil_head_get(int, u_long);
105 int pfil_add_hook(pfil_func_t, void *, int, struct pfil_head *);
106 int pfil_remove_hook(pfil_func_t, void *, int, struct pfil_head *);
107 #define PFIL_HOOKED(p) ((p)->ph_nhooks > 0)
109 /* Public functions to run the packet inspection by protocols. */
110 int pfil_run_hooks(struct pfil_head *, struct mbuf **, struct ifnet *,
111 int, struct inpcb *inp);
113 /* Public functions for pfil head management by protocols. */
114 int pfil_head_register(struct pfil_head *);
115 int pfil_head_unregister(struct pfil_head *);
117 /* Public pfil locking functions for self managed locks by packet filters. */
118 int pfil_try_rlock(struct pfil_head *, struct rm_priotracker *);
119 void pfil_rlock(struct pfil_head *, struct rm_priotracker *);
120 void pfil_runlock(struct pfil_head *, struct rm_priotracker *);
121 void pfil_wlock(struct pfil_head *);
122 void pfil_wunlock(struct pfil_head *);
123 int pfil_wowned(struct pfil_head *ph);
125 #endif /* _NET_PFIL_H_ */