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