1 /* 2 * Copyright (c) 2003 3 * Fraunhofer Institute for Open Communication Systems (FhG Fokus). 4 * All rights reserved. 5 * 6 * Author: Harti Brandt <harti@freebsd.org> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * 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 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 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 * $Begemot: bsnmp/snmpd/trans_udp.c,v 1.5 2005/10/04 08:46:56 brandt_h Exp $ 30 * 31 * UDP transport 32 */ 33 #include <sys/types.h> 34 #include <sys/queue.h> 35 36 #include <stdlib.h> 37 #include <syslog.h> 38 #include <string.h> 39 #include <errno.h> 40 #include <unistd.h> 41 42 #include <netinet/in.h> 43 #include <arpa/inet.h> 44 45 #include "snmpmod.h" 46 #include "snmpd.h" 47 #include "trans_udp.h" 48 #include "tree.h" 49 #include "oid.h" 50 51 static int udp_start(void); 52 static int udp_stop(int); 53 static void udp_close_port(struct tport *); 54 static int udp_init_port(struct tport *); 55 static ssize_t udp_send(struct tport *, const u_char *, size_t, 56 const struct sockaddr *, size_t); 57 58 /* exported */ 59 const struct transport_def udp_trans = { 60 "udp", 61 OIDX_begemotSnmpdTransUdp, 62 udp_start, 63 udp_stop, 64 udp_close_port, 65 udp_init_port, 66 udp_send 67 }; 68 static struct transport *my_trans; 69 70 static int 71 udp_start(void) 72 { 73 return (trans_register(&udp_trans, &my_trans)); 74 } 75 76 static int 77 udp_stop(int force __unused) 78 { 79 if (my_trans != NULL) 80 if (trans_unregister(my_trans) != 0) 81 return (SNMP_ERR_GENERR); 82 return (SNMP_ERR_NOERROR); 83 } 84 85 /* 86 * A UDP port is ready 87 */ 88 static void 89 udp_input(int fd __unused, void *udata) 90 { 91 struct udp_port *p = udata; 92 93 p->input.peerlen = sizeof(p->ret); 94 snmpd_input(&p->input, &p->tport); 95 } 96 97 /* 98 * Create a UDP socket and bind it to the given port 99 */ 100 static int 101 udp_init_port(struct tport *tp) 102 { 103 struct udp_port *p = (struct udp_port *)tp; 104 struct sockaddr_in addr; 105 u_int32_t ip; 106 const int on = 1; 107 108 if ((p->input.fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) { 109 syslog(LOG_ERR, "creating UDP socket: %m"); 110 return (SNMP_ERR_RES_UNAVAIL); 111 } 112 ip = (p->addr[0] << 24) | (p->addr[1] << 16) | (p->addr[2] << 8) | 113 p->addr[3]; 114 memset(&addr, 0, sizeof(addr)); 115 addr.sin_addr.s_addr = htonl(ip); 116 addr.sin_port = htons(p->port); 117 addr.sin_family = AF_INET; 118 addr.sin_len = sizeof(addr); 119 if (addr.sin_addr.s_addr == INADDR_ANY && 120 setsockopt(p->input.fd, IPPROTO_IP, IP_RECVDSTADDR, &on, 121 sizeof(on)) == -1) { 122 syslog(LOG_ERR, "setsockopt(IP_RECVDSTADDR): %m"); 123 close(p->input.fd); 124 p->input.fd = -1; 125 return (SNMP_ERR_GENERR); 126 } 127 if (bind(p->input.fd, (struct sockaddr *)&addr, sizeof(addr))) { 128 if (errno == EADDRNOTAVAIL) { 129 close(p->input.fd); 130 p->input.fd = -1; 131 return (SNMP_ERR_INCONS_NAME); 132 } 133 syslog(LOG_ERR, "bind: %s:%u %m", inet_ntoa(addr.sin_addr), 134 p->port); 135 close(p->input.fd); 136 p->input.fd = -1; 137 return (SNMP_ERR_GENERR); 138 } 139 if ((p->input.id = fd_select(p->input.fd, udp_input, 140 p, NULL)) == NULL) { 141 close(p->input.fd); 142 p->input.fd = -1; 143 return (SNMP_ERR_GENERR); 144 } 145 return (SNMP_ERR_NOERROR); 146 } 147 148 /* 149 * Create a new SNMP Port object and start it, if we are not 150 * in initialization mode. The arguments are in host byte order. 151 */ 152 static int 153 udp_open_port(u_int8_t *addr, u_int32_t udp_port, struct udp_port **pp) 154 { 155 struct udp_port *port; 156 int err; 157 158 if (udp_port > 0xffff) 159 return (SNMP_ERR_NO_CREATION); 160 if ((port = malloc(sizeof(*port))) == NULL) 161 return (SNMP_ERR_GENERR); 162 memset(port, 0, sizeof(*port)); 163 164 /* initialize common part */ 165 port->tport.index.len = 5; 166 port->tport.index.subs[0] = addr[0]; 167 port->tport.index.subs[1] = addr[1]; 168 port->tport.index.subs[2] = addr[2]; 169 port->tport.index.subs[3] = addr[3]; 170 port->tport.index.subs[4] = udp_port; 171 172 port->addr[0] = addr[0]; 173 port->addr[1] = addr[1]; 174 port->addr[2] = addr[2]; 175 port->addr[3] = addr[3]; 176 port->port = udp_port; 177 178 port->input.fd = -1; 179 port->input.id = NULL; 180 port->input.stream = 0; 181 port->input.cred = 0; 182 port->input.peer = (struct sockaddr *)&port->ret; 183 port->input.peerlen = sizeof(port->ret); 184 185 trans_insert_port(my_trans, &port->tport); 186 187 if (community != COMM_INITIALIZE && 188 (err = udp_init_port(&port->tport)) != SNMP_ERR_NOERROR) { 189 udp_close_port(&port->tport); 190 return (err); 191 } 192 *pp = port; 193 return (SNMP_ERR_NOERROR); 194 } 195 196 /* 197 * Close an SNMP port 198 */ 199 static void 200 udp_close_port(struct tport *tp) 201 { 202 struct udp_port *port = (struct udp_port *)tp; 203 204 snmpd_input_close(&port->input); 205 trans_remove_port(tp); 206 free(port); 207 } 208 209 /* 210 * Send something 211 */ 212 static ssize_t 213 udp_send(struct tport *tp, const u_char *buf, size_t len, 214 const struct sockaddr *addr, size_t addrlen) 215 { 216 struct udp_port *p = (struct udp_port *)tp; 217 218 return (sendto(p->input.fd, buf, len, 0, addr, addrlen)); 219 } 220 221 /* 222 * Port table 223 */ 224 int 225 op_snmp_port(struct snmp_context *ctx, struct snmp_value *value, 226 u_int sub, u_int iidx, enum snmp_op op) 227 { 228 asn_subid_t which = value->var.subs[sub-1]; 229 struct udp_port *p; 230 u_int8_t addr[4]; 231 u_int32_t port; 232 233 switch (op) { 234 235 case SNMP_OP_GETNEXT: 236 if ((p = (struct udp_port *)trans_next_port(my_trans, 237 &value->var, sub)) == NULL) 238 return (SNMP_ERR_NOSUCHNAME); 239 index_append(&value->var, sub, &p->tport.index); 240 break; 241 242 case SNMP_OP_GET: 243 if ((p = (struct udp_port *)trans_find_port(my_trans, 244 &value->var, sub)) == NULL) 245 return (SNMP_ERR_NOSUCHNAME); 246 break; 247 248 case SNMP_OP_SET: 249 p = (struct udp_port *)trans_find_port(my_trans, 250 &value->var, sub); 251 ctx->scratch->int1 = (p != NULL); 252 253 if (which != LEAF_begemotSnmpdPortStatus) 254 abort(); 255 if (!TRUTH_OK(value->v.integer)) 256 return (SNMP_ERR_WRONG_VALUE); 257 258 ctx->scratch->int2 = TRUTH_GET(value->v.integer); 259 260 if (ctx->scratch->int2) { 261 /* open an SNMP port */ 262 if (p != NULL) 263 /* already open - do nothing */ 264 return (SNMP_ERR_NOERROR); 265 266 if (index_decode(&value->var, sub, iidx, addr, &port)) 267 return (SNMP_ERR_NO_CREATION); 268 return (udp_open_port(addr, port, &p)); 269 270 } else { 271 /* close SNMP port - do in commit */ 272 } 273 return (SNMP_ERR_NOERROR); 274 275 case SNMP_OP_ROLLBACK: 276 p = (struct udp_port *)trans_find_port(my_trans, 277 &value->var, sub); 278 if (ctx->scratch->int1 == 0) { 279 /* did not exist */ 280 if (ctx->scratch->int2 == 1) { 281 /* created */ 282 if (p != NULL) 283 udp_close_port(&p->tport); 284 } 285 } 286 return (SNMP_ERR_NOERROR); 287 288 case SNMP_OP_COMMIT: 289 p = (struct udp_port *)trans_find_port(my_trans, 290 &value->var, sub); 291 if (ctx->scratch->int1 == 1) { 292 /* did exist */ 293 if (ctx->scratch->int2 == 0) { 294 /* delete */ 295 if (p != NULL) 296 udp_close_port(&p->tport); 297 } 298 } 299 return (SNMP_ERR_NOERROR); 300 301 default: 302 abort(); 303 } 304 305 /* 306 * Come here to fetch the value 307 */ 308 switch (which) { 309 310 case LEAF_begemotSnmpdPortStatus: 311 value->v.integer = 1; 312 break; 313 314 default: 315 abort(); 316 } 317 318 return (SNMP_ERR_NOERROR); 319 } 320