1 /* $NetBSD: pfil.h,v 1.22 2003/06/23 12:57:08 martin 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_WAITOK 0x00000004 59 #define PFIL_ALL (PFIL_IN|PFIL_OUT) 60 61 typedef TAILQ_HEAD(pfil_list, packet_filter_hook) pfil_list_t; 62 63 #define PFIL_TYPE_AF 1 /* key is AF_* type */ 64 #define PFIL_TYPE_IFNET 2 /* key is ifnet pointer */ 65 66 struct pfil_head { 67 pfil_list_t ph_in; 68 pfil_list_t ph_out; 69 int ph_type; 70 union { 71 u_long phu_val; 72 void *phu_ptr; 73 } ph_un; 74 #define ph_af ph_un.phu_val 75 #define ph_ifnet ph_un.phu_ptr 76 LIST_ENTRY(pfil_head) ph_list; 77 }; 78 typedef struct pfil_head pfil_head_t; 79 80 int pfil_run_hooks(struct pfil_head *, struct mbuf **, struct ifnet *, 81 int); 82 83 int pfil_add_hook(int (*func)(void *, struct mbuf **, 84 struct ifnet *, int), void *, int, struct pfil_head *); 85 int pfil_remove_hook(int (*func)(void *, struct mbuf **, 86 struct ifnet *, int), void *, int, struct pfil_head *); 87 88 int pfil_head_register(struct pfil_head *); 89 int pfil_head_unregister(struct pfil_head *); 90 91 struct pfil_head *pfil_head_get(int, u_long); 92 93 static __inline struct packet_filter_hook * 94 pfil_hook_get(int dir, struct pfil_head *ph) 95 { 96 97 if (dir == PFIL_IN) 98 return (TAILQ_FIRST(&ph->ph_in)); 99 else if (dir == PFIL_OUT) 100 return (TAILQ_FIRST(&ph->ph_out)); 101 else 102 return (NULL); 103 } 104 105 /* XXX */ 106 #if defined(_KERNEL_OPT) 107 #include "ipfilter.h" 108 #endif 109 110 #if NIPFILTER > 0 111 #ifdef PFIL_HOOKS 112 #undef PFIL_HOOKS 113 #endif 114 #define PFIL_HOOKS 115 #endif /* NIPFILTER */ 116 117 #endif /* _NET_PFIL_H_ */ 118