1/*- 2 * Copyright (c) 2005-2006 The FreeBSD Project 3 * All rights reserved. 4 * 5 * Author: Victor Cruceru <soc-victor@freebsd.org> 6 * 7 * Redistribution of this software and documentation and use in source and 8 * binary forms, with or without modification, are permitted provided that 9 * the following conditions are met: 10 * 11 * 1. Redistributions of source code or documentation must retain the above 12 * copyright notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD: releng/11.0/usr.sbin/bsnmpd/modules/snmp_hostres/hostres_network_tbl.c 160341 2006-07-14 09:07:56Z harti $ 30 */ 31 32/* 33 * Host Resources MIB implementation for SNMPd: instrumentation for 34 * hrNetworkTable 35 */ 36 37#include <sys/types.h> 38#include <sys/ioctl.h> 39#include <sys/socket.h> 40#include <sys/sysctl.h> 41 42#include <net/if.h> 43#include <net/if_mib.h> 44 45#include <assert.h> 46#include <ctype.h> 47#include <err.h> 48#include <errno.h> 49#include <ifaddrs.h> 50#include <stdarg.h> 51#include <stdlib.h> 52#include <string.h> 53#include <syslog.h> 54#include <unistd.h> 55 56#include "hostres_snmp.h" 57#include "hostres_oid.h" 58#include "hostres_tree.h" 59 60#include <bsnmp/snmp_mibII.h> 61 62/* 63 * This structure is used to hold a SNMP table entry 64 * for HOST-RESOURCES-MIB's hrNetworkTable 65 */ 66struct network_entry { 67 int32_t index; 68 int32_t ifIndex; 69 TAILQ_ENTRY(network_entry) link; 70#define HR_NETWORK_FOUND 0x001 71 uint32_t flags; 72 73}; 74TAILQ_HEAD(network_tbl, network_entry); 75 76/* the head of the list with hrNetworkTable's entries */ 77static struct network_tbl network_tbl = TAILQ_HEAD_INITIALIZER(network_tbl); 78 79/* last (agent) tick when hrNetworkTable was updated */ 80static uint64_t network_tick; 81 82/* maximum number of ticks between updates of network table */ 83uint32_t network_tbl_refresh = HR_NETWORK_TBL_REFRESH * 100; 84 85/* Constants */ 86static const struct asn_oid OIDX_hrDeviceNetwork_c = OIDX_hrDeviceNetwork; 87 88/** 89 * Create a new entry into the network table 90 */ 91static struct network_entry * 92network_entry_create(const struct device_entry *devEntry) 93{ 94 struct network_entry *entry; 95 96 assert(devEntry != NULL); 97 if (devEntry == NULL) 98 return (NULL); 99 100 if ((entry = malloc(sizeof(*entry))) == NULL) { 101 syslog(LOG_WARNING, "%s: %m", __func__); 102 return (NULL); 103 } 104 105 memset(entry, 0, sizeof(*entry)); 106 entry->index = devEntry->index; 107 INSERT_OBJECT_INT(entry, &network_tbl); 108 109 return (entry); 110} 111 112/** 113 * Delete an entry in the network table 114 */ 115static void 116network_entry_delete(struct network_entry* entry) 117{ 118 119 TAILQ_REMOVE(&network_tbl, entry, link); 120 free(entry); 121} 122 123/** 124 * Fetch the interfaces from the mibII module, get their real name from the 125 * kernel and try to find it in the device table. 126 */ 127static void 128network_get_interfaces(void) 129{ 130 struct device_entry *dev; 131 struct network_entry *net; 132 struct mibif *ifp; 133 int name[6]; 134 size_t len; 135 char *dname; 136 137 name[0] = CTL_NET; 138 name[1] = PF_LINK; 139 name[2] = NETLINK_GENERIC; 140 name[3] = IFMIB_IFDATA; 141 name[5] = IFDATA_DRIVERNAME; 142 143 for (ifp = mib_first_if(); ifp != NULL; ifp = mib_next_if(ifp)) { 144 HRDBG("%s %s", ifp->name, ifp->descr); 145 146 name[4] = ifp->sysindex; 147 148 /* get the original name */ 149 len = 0; 150 if (sysctl(name, 6, NULL, &len, 0, 0) < 0) { 151 syslog(LOG_ERR, "sysctl(net.link.ifdata.%d." 152 "drivername): %m", ifp->sysindex); 153 continue; 154 } 155 if ((dname = malloc(len)) == NULL) { 156 syslog(LOG_ERR, "malloc: %m"); 157 continue; 158 } 159 if (sysctl(name, 6, dname, &len, 0, 0) < 0) { 160 syslog(LOG_ERR, "sysctl(net.link.ifdata.%d." 161 "drivername): %m", ifp->sysindex); 162 free(dname); 163 continue; 164 } 165 166 HRDBG("got device %s (%s)", ifp->name, dname); 167 168 if ((dev = device_find_by_name(dname)) == NULL) { 169 HRDBG("%s not in hrDeviceTable", dname); 170 free(dname); 171 continue; 172 } 173 HRDBG("%s found in hrDeviceTable", dname); 174 175 dev->type = &OIDX_hrDeviceNetwork_c; 176 dev->flags |= HR_DEVICE_IMMUTABLE; 177 178 free(dname); 179 180 /* Then check hrNetworkTable for this device */ 181 TAILQ_FOREACH(net, &network_tbl, link) 182 if (net->index == dev->index) 183 break; 184 185 if (net == NULL && (net = network_entry_create(dev)) == NULL) 186 continue; 187 188 net->flags |= HR_NETWORK_FOUND; 189 net->ifIndex = ifp->index; 190 } 191 192 network_tick = this_tick; 193} 194 195/** 196 * Finalization routine for hrNetworkTable. 197 * It destroys the lists and frees any allocated heap memory. 198 */ 199void 200fini_network_tbl(void) 201{ 202 struct network_entry *n1; 203 204 while ((n1 = TAILQ_FIRST(&network_tbl)) != NULL) { 205 TAILQ_REMOVE(&network_tbl, n1, link); 206 free(n1); 207 } 208} 209 210/** 211 * Get the interface list from mibII only at this point to be sure that 212 * it is there already. 213 */ 214void 215start_network_tbl(void) 216{ 217 218 mib_refresh_iflist(); 219 network_get_interfaces(); 220} 221 222/** 223 * Refresh the table. 224 */ 225static void 226refresh_network_tbl(void) 227{ 228 struct network_entry *entry, *entry_tmp; 229 230 if (this_tick - network_tick < network_tbl_refresh) { 231 HRDBG("no refresh needed"); 232 return; 233 } 234 235 /* mark each entry as missing */ 236 TAILQ_FOREACH(entry, &network_tbl, link) 237 entry->flags &= ~HR_NETWORK_FOUND; 238 239 network_get_interfaces(); 240 241 /* 242 * Purge items that disappeared 243 */ 244 TAILQ_FOREACH_SAFE(entry, &network_tbl, link, entry_tmp) { 245 if (!(entry->flags & HR_NETWORK_FOUND)) 246 network_entry_delete(entry); 247 } 248 249 HRDBG("refresh DONE"); 250} 251 252/* 253 * This is the implementation for a generated (by our SNMP tool) 254 * function prototype, see hostres_tree.h 255 * It handles the SNMP operations for hrNetworkTable 256 */ 257int 258op_hrNetworkTable(struct snmp_context *ctx __unused, struct snmp_value *value, 259 u_int sub, u_int iidx __unused, enum snmp_op curr_op) 260{ 261 struct network_entry *entry; 262 263 refresh_network_tbl(); 264 265 switch (curr_op) { 266 267 case SNMP_OP_GETNEXT: 268 if ((entry = NEXT_OBJECT_INT(&network_tbl, 269 &value->var, sub)) == NULL) 270 return (SNMP_ERR_NOSUCHNAME); 271 value->var.len = sub + 1; 272 value->var.subs[sub] = entry->index; 273 goto get; 274 275 case SNMP_OP_GET: 276 if ((entry = FIND_OBJECT_INT(&network_tbl, 277 &value->var, sub)) == NULL) 278 return (SNMP_ERR_NOSUCHNAME); 279 goto get; 280 281 case SNMP_OP_SET: 282 if ((entry = FIND_OBJECT_INT(&network_tbl, 283 &value->var, sub)) == NULL) 284 return (SNMP_ERR_NO_CREATION); 285 return (SNMP_ERR_NOT_WRITEABLE); 286 287 case SNMP_OP_ROLLBACK: 288 case SNMP_OP_COMMIT: 289 abort(); 290 } 291 abort(); 292 293 get: 294 switch (value->var.subs[sub - 1]) { 295 296 case LEAF_hrNetworkIfIndex: 297 value->v.integer = entry->ifIndex; 298 return (SNMP_ERR_NOERROR); 299 300 } 301 abort(); 302} 303