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 * $FreeBSD$ 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 */ 66 struct 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 }; 74 TAILQ_HEAD(network_tbl, network_entry); 75 76 /* the head of the list with hrNetworkTable's entries */ 77 static struct network_tbl network_tbl = TAILQ_HEAD_INITIALIZER(network_tbl); 78 79 /* last (agent) tick when hrNetworkTable was updated */ 80 static uint64_t network_tick; 81 82 /* maximum number of ticks between updates of network table */ 83 uint32_t network_tbl_refresh = HR_NETWORK_TBL_REFRESH * 100; 84 85 /* Constants */ 86 static const struct asn_oid OIDX_hrDeviceNetwork_c = OIDX_hrDeviceNetwork; 87 88 /** 89 * Create a new entry into the network table 90 */ 91 static struct network_entry * 92 network_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 */ 115 static void 116 network_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 */ 127 static void 128 network_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 */ 199 void 200 fini_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 */ 214 void 215 start_network_tbl(void) 216 { 217 218 mib_refresh_iflist(); 219 network_get_interfaces(); 220 } 221 222 /** 223 * Refresh the table. 224 */ 225 static void 226 refresh_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 */ 257 int 258 op_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