1 /* $NetBSD: npf_ext_log.c,v 1.9 2016/06/16 03:03:33 ozaki-r 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 1.9 2016/06/16 03:03:33 ozaki-r 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 struct psref psref; 89 90 /* Set the address family. */ 91 if (npf_iscached(npc, NPC_IP4)) { 92 family = AF_INET; 93 } else if (npf_iscached(npc, NPC_IP6)) { 94 family = AF_INET6; 95 } else { 96 family = AF_UNSPEC; 97 } 98 99 KERNEL_LOCK(1, NULL); 100 101 /* Find a pseudo-interface to log. */ 102 ifp = if_get_byindex(log->if_idx, &psref); 103 if (ifp == NULL) { 104 /* No interface. */ 105 KERNEL_UNLOCK_ONE(NULL); 106 return true; 107 } 108 109 /* Pass through BPF. */ 110 ifp->if_opackets++; 111 ifp->if_obytes += m->m_pkthdr.len; 112 bpf_mtap_af(ifp, family, m); 113 if_put(ifp, &psref); 114 KERNEL_UNLOCK_ONE(NULL); 115 116 return true; 117 } 118 119 /* 120 * Module interface. 121 */ 122 static int 123 npf_ext_log_modcmd(modcmd_t cmd, void *arg) 124 { 125 static const npf_ext_ops_t npf_log_ops = { 126 .version = NPFEXT_LOG_VER, 127 .ctx = NULL, 128 .ctor = npf_log_ctor, 129 .dtor = npf_log_dtor, 130 .proc = npf_log 131 }; 132 int error; 133 134 switch (cmd) { 135 case MODULE_CMD_INIT: 136 /* 137 * Initialise the NPF logging extension. 138 */ 139 npf_ext_log_id = npf_ext_register("log", &npf_log_ops); 140 if (!npf_ext_log_id) { 141 return EEXIST; 142 } 143 break; 144 145 case MODULE_CMD_FINI: 146 error = npf_ext_unregister(npf_ext_log_id); 147 if (error) { 148 return error; 149 } 150 break; 151 152 case MODULE_CMD_AUTOUNLOAD: 153 /* Allow auto-unload only if NPF permits it. */ 154 return npf_autounload_p() ? 0 : EBUSY; 155 156 default: 157 return ENOTTY; 158 } 159 return 0; 160 } 161