1 /* $NetBSD: pfil.h,v 1.28 2006/02/16 20:17:20 perry 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 #ifdef _KERNEL_OPT 35 #include "opt_pfil_hooks.h" 36 #endif 37 38 #include <sys/queue.h> 39 #include <net/dlt.h> 40 #include <sys/null.h> 41 42 struct mbuf; 43 struct ifnet; 44 45 /* 46 * The packet filter hooks are designed for anything to call them to 47 * possibly intercept the packet. 48 */ 49 struct packet_filter_hook { 50 TAILQ_ENTRY(packet_filter_hook) pfil_link; 51 int (*pfil_func)(void *, struct mbuf **, struct ifnet *, int); 52 void *pfil_arg; 53 int pfil_flags; 54 }; 55 56 #define PFIL_IN 0x00000001 57 #define PFIL_OUT 0x00000002 58 #define PFIL_ALL (PFIL_IN|PFIL_OUT) 59 #define PFIL_WAITOK 0x00000004 60 #define PFIL_IFADDR 0x00000008 61 #define PFIL_IFNET 0x00000010 62 63 /* events notified by PFIL_IFNET */ 64 #define PFIL_IFNET_ATTACH 0 65 #define PFIL_IFNET_DETACH 1 66 67 typedef TAILQ_HEAD(pfil_list, packet_filter_hook) pfil_list_t; 68 69 #define PFIL_TYPE_AF 1 /* key is AF_* type */ 70 #define PFIL_TYPE_IFNET 2 /* key is ifnet pointer */ 71 72 struct pfil_head { 73 pfil_list_t ph_in; 74 pfil_list_t ph_out; 75 pfil_list_t ph_ifaddr; 76 pfil_list_t ph_ifnetevent; /* XXX naming collision */ 77 int ph_type; 78 union { 79 u_long phu_val; 80 void *phu_ptr; 81 } ph_un; 82 #define ph_af ph_un.phu_val 83 #define ph_ifnet ph_un.phu_ptr 84 LIST_ENTRY(pfil_head) ph_list; 85 }; 86 typedef struct pfil_head pfil_head_t; 87 88 #ifdef _KERNEL 89 90 int pfil_run_hooks(struct pfil_head *, struct mbuf **, struct ifnet *, 91 int); 92 93 int pfil_add_hook(int (*func)(void *, struct mbuf **, 94 struct ifnet *, int), void *, int, struct pfil_head *); 95 int pfil_remove_hook(int (*func)(void *, struct mbuf **, 96 struct ifnet *, int), void *, int, struct pfil_head *); 97 98 int pfil_head_register(struct pfil_head *); 99 int pfil_head_unregister(struct pfil_head *); 100 101 struct pfil_head *pfil_head_get(int, u_long); 102 103 static __inline struct packet_filter_hook * 104 pfil_hook_get(int dir, struct pfil_head *ph) 105 { 106 107 if (dir == PFIL_IN) 108 return (TAILQ_FIRST(&ph->ph_in)); 109 else if (dir == PFIL_OUT) 110 return (TAILQ_FIRST(&ph->ph_out)); 111 else if (dir == PFIL_IFADDR) 112 return (TAILQ_FIRST(&ph->ph_ifaddr)); 113 else if (dir == PFIL_IFNET) 114 return (TAILQ_FIRST(&ph->ph_ifnetevent)); 115 else 116 return (NULL); 117 } 118 119 #endif /* _KERNEL */ 120 121 /* XXX */ 122 #if defined(_KERNEL_OPT) 123 #include "ipfilter.h" 124 #endif 125 126 #if NIPFILTER > 0 127 #ifdef PFIL_HOOKS 128 #undef PFIL_HOOKS 129 #endif 130 #define PFIL_HOOKS 131 #endif /* NIPFILTER */ 132 133 #ifdef _KERNEL 134 /* in sys/net/if.c */ 135 extern struct pfil_head if_pfil; /* packet filtering hook for interfaces */ 136 #endif /* _KERNEL */ 137 138 #endif /* !_NET_PFIL_H_ */ 139