xref: /dragonfly/sys/net/pfil.h (revision af79c6e5)
1 /*	$NetBSD: pfil.h,v 1.22 2003/06/23 12:57:08 martin Exp $	*/
2 /* $DragonFly: src/sys/net/pfil.h,v 1.1 2003/12/02 09:18:17 asmodai Exp $ */
3 
4 /*
5  * Copyright (c) 1996 Matthew R. Green
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
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.
18  *
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
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef _NET_PFIL_H_
33 #define _NET_PFIL_H_
34 
35 #ifdef _KERNEL_OPT
36 #include "opt_pfil_hooks.h"
37 #endif
38 
39 #include <sys/queue.h>
40 
41 struct mbuf;
42 struct ifnet;
43 
44 /*
45  * The packet filter hooks are designed for anything to call them to
46  * possibly intercept the packet.
47  */
48 struct packet_filter_hook {
49         TAILQ_ENTRY(packet_filter_hook) pfil_link;
50 	int	(*pfil_func)(void *, struct mbuf **, struct ifnet *, int);
51 	void	*pfil_arg;
52 	int	pfil_flags;
53 };
54 
55 #define PFIL_IN		0x00000001
56 #define PFIL_OUT	0x00000002
57 #define PFIL_WAITOK	0x00000004
58 #define PFIL_ALL	(PFIL_IN|PFIL_OUT)
59 
60 typedef	TAILQ_HEAD(pfil_list, packet_filter_hook) pfil_list_t;
61 
62 #define	PFIL_TYPE_AF		1	/* key is AF_* type */
63 #define	PFIL_TYPE_IFNET		2	/* key is ifnet pointer */
64 
65 struct pfil_head {
66 	pfil_list_t	ph_in;
67 	pfil_list_t	ph_out;
68 	int		ph_type;
69 	union {
70 		u_long		phu_val;
71 		void		*phu_ptr;
72 	} ph_un;
73 #define	ph_af		ph_un.phu_val
74 #define	ph_ifnet	ph_un.phu_ptr
75 	LIST_ENTRY(pfil_head) ph_list;
76 };
77 typedef struct pfil_head pfil_head_t;
78 
79 int	pfil_run_hooks(struct pfil_head *, struct mbuf **, struct ifnet *,
80 	    int);
81 
82 int	pfil_add_hook(int (*func)(void *, struct mbuf **,
83 	    struct ifnet *, int), void *, int, struct pfil_head *);
84 int	pfil_remove_hook(int (*func)(void *, struct mbuf **,
85 	    struct ifnet *, int), void *, int, struct pfil_head *);
86 
87 int	pfil_head_register(struct pfil_head *);
88 int	pfil_head_unregister(struct pfil_head *);
89 
90 struct pfil_head *pfil_head_get(int, u_long);
91 
92 static __inline struct packet_filter_hook *
93 pfil_hook_get(int dir, struct pfil_head *ph)
94 {
95 
96 	if (dir == PFIL_IN)
97 		return (TAILQ_FIRST(&ph->ph_in));
98 	else if (dir == PFIL_OUT)
99 		return (TAILQ_FIRST(&ph->ph_out));
100 	else
101 		return (NULL);
102 }
103 
104 /* XXX */
105 #if defined(_KERNEL_OPT)
106 #include "ipfilter.h"
107 #endif
108 
109 #if NIPFILTER > 0
110 #ifdef PFIL_HOOKS
111 #undef PFIL_HOOKS
112 #endif
113 #define PFIL_HOOKS
114 #endif /* NIPFILTER */
115 
116 #endif /* _NET_PFIL_H_ */
117