1 /* $NetBSD: pfil.h,v 1.20 2001/05/30 12:04:53 mrg Exp $ */ 2 3 /* 4 * Copyright (c) 1996 Matthew R. Green 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 23 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 25 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #ifndef _NET_PFIL_H_ 32 #define _NET_PFIL_H_ 33 34 #include <sys/queue.h> 35 #include <net/dlt.h> 36 #include <sys/null.h> 37 38 struct mbuf; 39 struct ifnet; 40 41 /* 42 * The packet filter hooks are designed for anything to call them to 43 * possibly intercept the packet. 44 */ 45 struct packet_filter_hook { 46 TAILQ_ENTRY(packet_filter_hook) pfil_link; 47 int (*pfil_func)(void *, struct mbuf **, struct ifnet *, int); 48 void *pfil_arg; 49 int pfil_flags; 50 }; 51 52 #define PFIL_IN 0x00000001 53 #define PFIL_OUT 0x00000002 54 #define PFIL_WAITOK 0x00000004 55 #define PFIL_ALL (PFIL_IN|PFIL_OUT) 56 57 typedef TAILQ_HEAD(pfil_list, packet_filter_hook) pfil_list_t; 58 59 #define PFIL_TYPE_AF 1 /* key is AF_* type */ 60 #define PFIL_TYPE_IFNET 2 /* key is ifnet pointer */ 61 62 struct pfil_head { 63 pfil_list_t ph_in; 64 pfil_list_t ph_out; 65 int ph_type; 66 union { 67 u_long phu_val; 68 void *phu_ptr; 69 } ph_un; 70 #define ph_af ph_un.phu_val 71 #define ph_ifnet ph_un.phu_ptr 72 LIST_ENTRY(pfil_head) ph_list; 73 }; 74 typedef struct pfil_head pfil_head_t; 75 76 int pfil_run_hooks(struct pfil_head *, struct mbuf **, struct ifnet *, 77 int); 78 79 int pfil_add_hook(int (*func)(void *, struct mbuf **, 80 struct ifnet *, int), void *, int, struct pfil_head *); 81 int pfil_remove_hook(int (*func)(void *, struct mbuf **, 82 struct ifnet *, int), void *, int, struct pfil_head *); 83 84 int pfil_head_register(struct pfil_head *); 85 int pfil_head_unregister(struct pfil_head *); 86 87 struct pfil_head *pfil_head_get(int, u_long); 88 89 static __inline struct packet_filter_hook * 90 pfil_hook_get(int dir, struct pfil_head *ph) 91 { 92 93 if (dir == PFIL_IN) 94 return (TAILQ_FIRST(&ph->ph_in)); 95 else if (dir == PFIL_OUT) 96 return (TAILQ_FIRST(&ph->ph_out)); 97 else 98 return (NULL); 99 } 100 101 /* XXX */ 102 #if defined(_KERNEL_OPT) 103 #include "ipfilter.h" 104 #endif 105 106 #if NIPFILTER > 0 107 #ifdef PFIL_HOOKS 108 #undef PFIL_HOOKS 109 #endif 110 #define PFIL_HOOKS 111 #endif /* NIPFILTER */ 112 113 #endif /* _NET_PFIL_H_ */ 114