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) 2019 Gleb Smirnoff <glebius@FreeBSD.org>
8 * Copyright (c) 1996 Matthew R. Green
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 #include <sys/ioccom.h>
46 #define MAXPFILNAME 64
49 char pio_name[MAXPFILNAME];
52 enum pfil_types pio_type;
56 char pio_module[MAXPFILNAME];
57 char pio_ruleset[MAXPFILNAME];
59 enum pfil_types pio_type;
65 struct pfilioc_head *pio_heads;
66 struct pfilioc_hook *pio_hooks;
70 char pio_name[MAXPFILNAME];
71 char pio_module[MAXPFILNAME];
72 char pio_ruleset[MAXPFILNAME];
76 #define PFILDEV "pfil"
77 #define PFILIOC_LISTHEADS _IOWR('P', 1, struct pfilioc_list)
78 #define PFILIOC_LISTHOOKS _IOWR('P', 2, struct pfilioc_list)
79 #define PFILIOC_LINK _IOW('P', 3, struct pfilioc_link)
81 #define PFIL_IN 0x00010000
82 #define PFIL_OUT 0x00020000
83 #define PFIL_FWD 0x00040000
84 #define PFIL_DIR(f) ((f) & (PFIL_IN|PFIL_OUT))
85 #define PFIL_MEMPTR 0x00080000
86 #define PFIL_HEADPTR 0x00100000
87 #define PFIL_HOOKPTR 0x00200000
88 #define PFIL_APPEND 0x00400000
89 #define PFIL_UNLINK 0x00800000
90 #define PFIL_LENMASK 0x0000ffff
91 #define PFIL_LENGTH(f) ((f) & PFIL_LENMASK)
102 } pfil_packet_t __attribute__((__transparent_union__));
104 static inline pfil_packet_t
105 pfil_packet_align(pfil_packet_t p)
108 return ((pfil_packet_t ) (((uintptr_t)(p).mem +
109 (_Alignof(void *) - 1)) & - _Alignof(void *)));
112 static inline struct mbuf *
113 pfil_mem2mbuf(void *v)
116 return (*(struct mbuf **) (((uintptr_t)(v) +
117 (_Alignof(void *) - 1)) & - _Alignof(void *)));
127 typedef pfil_return_t (*pfil_func_t)(pfil_packet_t, struct ifnet *, int,
128 void *, struct inpcb *);
130 * A pfil head is created by a packet intercept point.
132 * A pfil hook is created by a packet filter.
134 * Hooks are chained on heads. Historically some hooking happens
135 * automatically, e.g. ipfw(4), pf(4) and ipfilter(4) would register
136 * theirselves on IPv4 and IPv6 input/output.
139 typedef struct pfil_hook * pfil_hook_t;
140 typedef struct pfil_head * pfil_head_t;
143 * Give us a chance to modify pfil_xxx_args structures in future.
145 #define PFIL_VERSION 1
147 /* Argument structure used by packet filters to register themselves. */
148 struct pfil_hook_args {
151 enum pfil_types pa_type;
154 const char *pa_modname;
155 const char *pa_rulname;
158 /* Public functions for pfil hook management by packet filters. */
159 pfil_hook_t pfil_add_hook(struct pfil_hook_args *);
160 void pfil_remove_hook(pfil_hook_t);
162 /* Argument structure used by ioctl() and packet filters to set filters. */
163 struct pfil_link_args {
167 const char *pa_headname;
172 const char *pa_modname;
173 const char *pa_rulname;
179 /* Public function to configure filter chains. Used by ioctl() and filters. */
180 int pfil_link(struct pfil_link_args *);
182 /* Argument structure used by inspection points to register themselves. */
183 struct pfil_head_args {
186 enum pfil_types pa_type;
187 const char *pa_headname;
190 /* Public functions for pfil head management by inspection points. */
191 pfil_head_t pfil_head_register(struct pfil_head_args *);
192 void pfil_head_unregister(pfil_head_t);
194 /* Public functions to run the packet inspection by inspection points. */
195 int pfil_run_hooks(struct pfil_head *, pfil_packet_t, struct ifnet *, int,
198 * Minimally exposed structure to avoid function call in case of absence
199 * of any filters by protocols and macros to do the check.
205 #define PFIL_HOOKED_IN(p) (((struct _pfil_head *)(p))->head_nhooksin > 0)
206 #define PFIL_HOOKED_OUT(p) (((struct _pfil_head *)(p))->head_nhooksout > 0)
209 * Alloc mbuf to be used instead of memory pointer.
211 int pfil_realloc(pfil_packet_t *, int, struct ifnet *);
214 #endif /* _NET_PFIL_H_ */