1 /* $NetBSD: npf_ext_log.c,v 1.8 2014/07/20 00:37:41 rmind Exp $ */ 2 3 /*- 4 * Copyright (c) 2010-2012 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This material is based upon work partially supported by The 8 * NetBSD Foundation under a contract with Mindaugas Rasiukevicius. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * NPF logging extension. 34 */ 35 36 #include <sys/cdefs.h> 37 __KERNEL_RCSID(0, "$NetBSD: npf_ext_log.c,v 1.8 2014/07/20 00:37:41 rmind Exp $"); 38 39 #include <sys/types.h> 40 #include <sys/module.h> 41 42 #include <sys/conf.h> 43 #include <sys/kmem.h> 44 #include <sys/mbuf.h> 45 #include <sys/mutex.h> 46 #include <sys/queue.h> 47 48 #include <net/if.h> 49 #include <net/if_types.h> 50 #include <net/bpf.h> 51 52 #include "npf_impl.h" 53 54 NPF_EXT_MODULE(npf_ext_log, ""); 55 56 #define NPFEXT_LOG_VER 1 57 58 static void * npf_ext_log_id; 59 60 typedef struct { 61 unsigned int if_idx; 62 } npf_ext_log_t; 63 64 static int 65 npf_log_ctor(npf_rproc_t *rp, prop_dictionary_t params) 66 { 67 npf_ext_log_t *meta; 68 69 meta = kmem_zalloc(sizeof(npf_ext_log_t), KM_SLEEP); 70 prop_dictionary_get_uint32(params, "log-interface", &meta->if_idx); 71 npf_rproc_assign(rp, meta); 72 return 0; 73 } 74 75 static void 76 npf_log_dtor(npf_rproc_t *rp, void *meta) 77 { 78 kmem_free(meta, sizeof(npf_ext_log_t)); 79 } 80 81 static bool 82 npf_log(npf_cache_t *npc, void *meta, int *decision) 83 { 84 struct mbuf *m = nbuf_head_mbuf(npc->npc_nbuf); 85 const npf_ext_log_t *log = meta; 86 ifnet_t *ifp; 87 int family; 88 89 /* Set the address family. */ 90 if (npf_iscached(npc, NPC_IP4)) { 91 family = AF_INET; 92 } else if (npf_iscached(npc, NPC_IP6)) { 93 family = AF_INET6; 94 } else { 95 family = AF_UNSPEC; 96 } 97 98 KERNEL_LOCK(1, NULL); 99 100 /* Find a pseudo-interface to log. */ 101 ifp = if_byindex(log->if_idx); 102 if (ifp == NULL) { 103 /* No interface. */ 104 KERNEL_UNLOCK_ONE(NULL); 105 return true; 106 } 107 108 /* Pass through BPF. */ 109 ifp->if_opackets++; 110 ifp->if_obytes += m->m_pkthdr.len; 111 bpf_mtap_af(ifp, family, m); 112 KERNEL_UNLOCK_ONE(NULL); 113 114 return true; 115 } 116 117 /* 118 * Module interface. 119 */ 120 static int 121 npf_ext_log_modcmd(modcmd_t cmd, void *arg) 122 { 123 static const npf_ext_ops_t npf_log_ops = { 124 .version = NPFEXT_LOG_VER, 125 .ctx = NULL, 126 .ctor = npf_log_ctor, 127 .dtor = npf_log_dtor, 128 .proc = npf_log 129 }; 130 int error; 131 132 switch (cmd) { 133 case MODULE_CMD_INIT: 134 /* 135 * Initialise the NPF logging extension. 136 */ 137 npf_ext_log_id = npf_ext_register("log", &npf_log_ops); 138 if (!npf_ext_log_id) { 139 return EEXIST; 140 } 141 break; 142 143 case MODULE_CMD_FINI: 144 error = npf_ext_unregister(npf_ext_log_id); 145 if (error) { 146 return error; 147 } 148 break; 149 150 case MODULE_CMD_AUTOUNLOAD: 151 /* Allow auto-unload only if NPF permits it. */ 152 return npf_autounload_p() ? 0 : EBUSY; 153 154 default: 155 return ENOTTY; 156 } 157 return 0; 158 } 159