1 /* $NetBSD: npf_ext_log.c,v 1.10 2016/12/26 23:05:06 christos 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 #ifdef _KERNEL 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: npf_ext_log.c,v 1.10 2016/12/26 23:05:06 christos Exp $"); 39 40 #include <sys/types.h> 41 #include <sys/module.h> 42 43 #include <sys/conf.h> 44 #include <sys/kmem.h> 45 #include <sys/mbuf.h> 46 #include <sys/mutex.h> 47 #include <sys/queue.h> 48 49 #include <net/if.h> 50 #include <net/if_types.h> 51 #include <net/bpf.h> 52 #endif 53 54 #include "npf_impl.h" 55 56 NPF_EXT_MODULE(npf_ext_log, ""); 57 58 #define NPFEXT_LOG_VER 1 59 60 static void * npf_ext_log_id; 61 62 typedef struct { 63 unsigned int if_idx; 64 } npf_ext_log_t; 65 66 static int 67 npf_log_ctor(npf_rproc_t *rp, prop_dictionary_t params) 68 { 69 npf_ext_log_t *meta; 70 71 meta = kmem_zalloc(sizeof(npf_ext_log_t), KM_SLEEP); 72 prop_dictionary_get_uint32(params, "log-interface", &meta->if_idx); 73 npf_rproc_assign(rp, meta); 74 return 0; 75 } 76 77 static void 78 npf_log_dtor(npf_rproc_t *rp, void *meta) 79 { 80 kmem_free(meta, sizeof(npf_ext_log_t)); 81 } 82 83 static bool 84 npf_log(npf_cache_t *npc, void *meta, int *decision) 85 { 86 struct mbuf *m = nbuf_head_mbuf(npc->npc_nbuf); 87 const npf_ext_log_t *log = meta; 88 struct psref psref; 89 ifnet_t *ifp; 90 int family; 91 92 /* Set the address family. */ 93 if (npf_iscached(npc, NPC_IP4)) { 94 family = AF_INET; 95 } else if (npf_iscached(npc, NPC_IP6)) { 96 family = AF_INET6; 97 } else { 98 family = AF_UNSPEC; 99 } 100 101 KERNEL_LOCK(1, NULL); 102 103 /* Find a pseudo-interface to log. */ 104 ifp = if_get_byindex(log->if_idx, &psref); 105 if (ifp == NULL) { 106 /* No interface. */ 107 KERNEL_UNLOCK_ONE(NULL); 108 return true; 109 } 110 111 /* Pass through BPF. */ 112 ifp->if_opackets++; 113 ifp->if_obytes += m->m_pkthdr.len; 114 bpf_mtap_af(ifp, family, m); 115 if_put(ifp, &psref); 116 117 KERNEL_UNLOCK_ONE(NULL); 118 119 return true; 120 } 121 122 /* 123 * Module interface. 124 */ 125 static int 126 npf_ext_log_modcmd(modcmd_t cmd, void *arg) 127 { 128 static const npf_ext_ops_t npf_log_ops = { 129 .version = NPFEXT_LOG_VER, 130 .ctx = NULL, 131 .ctor = npf_log_ctor, 132 .dtor = npf_log_dtor, 133 .proc = npf_log 134 }; 135 npf_t *npf = npf_getkernctx(); 136 int error; 137 138 switch (cmd) { 139 case MODULE_CMD_INIT: 140 /* 141 * Initialise the NPF logging extension. 142 */ 143 npf_ext_log_id = npf_ext_register(npf, "log", &npf_log_ops); 144 if (!npf_ext_log_id) { 145 return EEXIST; 146 } 147 break; 148 149 case MODULE_CMD_FINI: 150 error = npf_ext_unregister(npf, npf_ext_log_id); 151 if (error) { 152 return error; 153 } 154 break; 155 156 case MODULE_CMD_AUTOUNLOAD: 157 /* Allow auto-unload only if NPF permits it. */ 158 return npf_autounload_p() ? 0 : EBUSY; 159 160 default: 161 return ENOTTY; 162 } 163 return 0; 164 } 165