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 35 #include <stdlib.h> 36 #include <syslog.h> 37 #include <string.h> 38 #include <errno.h> 39 #include <unistd.h> 40 41 #include <netinet/in.h> 42 #include <arpa/inet.h> 43 44 #include "snmpmod.h" 45 #include "snmpd.h" 46 #include "trans_udp.h" 47 #include "tree.h" 48 #include "oid.h" 49 50 static int udp_start(void); 51 static int udp_stop(int); 52 static void udp_close_port(struct tport *); 53 static int udp_init_port(struct tport *); 54 static ssize_t udp_send(struct tport *, const u_char *, size_t, 55 const struct sockaddr *, size_t); 56 57 /* exported */ 58 const struct transport_def udp_trans = { 59 "udp", 60 OIDX_begemotSnmpdTransUdp, 61 udp_start, 62 udp_stop, 63 udp_close_port, 64 udp_init_port, 65 udp_send 66 }; 67 static struct transport *my_trans; 68 69 static int 70 udp_start(void) 71 { 72 return (trans_register(&udp_trans, &my_trans)); 73 } 74 75 static int 76 udp_stop(int force __unused) 77 { 78 if (my_trans != NULL) 79 if (trans_unregister(my_trans) != 0) 80 return (SNMP_ERR_GENERR); 81 return (SNMP_ERR_NOERROR); 82 } 83 84 /* 85 * A UDP port is ready 86 */ 87 static void 88 udp_input(int fd __unused, void *udata) 89 { 90 struct udp_port *p = udata; 91 92 p->input.peerlen = sizeof(p->ret); 93 snmpd_input(&p->input, &p->tport); 94 } 95 96 /* 97 * Create a UDP socket and bind it to the given port 98 */ 99 static int 100 udp_init_port(struct tport *tp) 101 { 102 struct udp_port *p = (struct udp_port *)tp; 103 struct sockaddr_in addr; 104 u_int32_t ip; 105 106 if ((p->input.fd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) { 107 syslog(LOG_ERR, "creating UDP socket: %m"); 108 return (SNMP_ERR_RES_UNAVAIL); 109 } 110 ip = (p->addr[0] << 24) | (p->addr[1] << 16) | (p->addr[2] << 8) | 111 p->addr[3]; 112 memset(&addr, 0, sizeof(addr)); 113 addr.sin_addr.s_addr = htonl(ip); 114 addr.sin_port = htons(p->port); 115 addr.sin_family = AF_INET; 116 addr.sin_len = sizeof(addr); 117 if (bind(p->input.fd, (struct sockaddr *)&addr, sizeof(addr))) { 118 if (errno == EADDRNOTAVAIL) { 119 close(p->input.fd); 120 p->input.fd = -1; 121 return (SNMP_ERR_INCONS_NAME); 122 } 123 syslog(LOG_ERR, "bind: %s:%u %m", inet_ntoa(addr.sin_addr), 124 p->port); 125 close(p->input.fd); 126 p->input.fd = -1; 127 return (SNMP_ERR_GENERR); 128 } 129 if ((p->input.id = fd_select(p->input.fd, udp_input, 130 p, NULL)) == NULL) { 131 close(p->input.fd); 132 p->input.fd = -1; 133 return (SNMP_ERR_GENERR); 134 } 135 return (SNMP_ERR_NOERROR); 136 } 137 138 /* 139 * Create a new SNMP Port object and start it, if we are not 140 * in initialization mode. The arguments are in host byte order. 141 */ 142 static int 143 udp_open_port(u_int8_t *addr, u_int32_t udp_port, struct udp_port **pp) 144 { 145 struct udp_port *port; 146 int err; 147 148 if (udp_port > 0xffff) 149 return (SNMP_ERR_NO_CREATION); 150 if ((port = malloc(sizeof(*port))) == NULL) 151 return (SNMP_ERR_GENERR); 152 memset(port, 0, sizeof(*port)); 153 154 /* initialize common part */ 155 port->tport.index.len = 5; 156 port->tport.index.subs[0] = addr[0]; 157 port->tport.index.subs[1] = addr[1]; 158 port->tport.index.subs[2] = addr[2]; 159 port->tport.index.subs[3] = addr[3]; 160 port->tport.index.subs[4] = udp_port; 161 162 port->addr[0] = addr[0]; 163 port->addr[1] = addr[1]; 164 port->addr[2] = addr[2]; 165 port->addr[3] = addr[3]; 166 port->port = udp_port; 167 168 port->input.fd = -1; 169 port->input.id = NULL; 170 port->input.stream = 0; 171 port->input.cred = 0; 172 port->input.peer = (struct sockaddr *)&port->ret; 173 port->input.peerlen = sizeof(port->ret); 174 175 trans_insert_port(my_trans, &port->tport); 176 177 if (community != COMM_INITIALIZE && 178 (err = udp_init_port(&port->tport)) != SNMP_ERR_NOERROR) { 179 udp_close_port(&port->tport); 180 return (err); 181 } 182 *pp = port; 183 return (SNMP_ERR_NOERROR); 184 } 185 186 /* 187 * Close an SNMP port 188 */ 189 static void 190 udp_close_port(struct tport *tp) 191 { 192 struct udp_port *port = (struct udp_port *)tp; 193 194 snmpd_input_close(&port->input); 195 trans_remove_port(tp); 196 free(port); 197 } 198 199 /* 200 * Send something 201 */ 202 static ssize_t 203 udp_send(struct tport *tp, const u_char *buf, size_t len, 204 const struct sockaddr *addr, size_t addrlen) 205 { 206 struct udp_port *p = (struct udp_port *)tp; 207 208 return (sendto(p->input.fd, buf, len, 0, addr, addrlen)); 209 } 210 211 /* 212 * Port table 213 */ 214 int 215 op_snmp_port(struct snmp_context *ctx, struct snmp_value *value, 216 u_int sub, u_int iidx, enum snmp_op op) 217 { 218 asn_subid_t which = value->var.subs[sub-1]; 219 struct udp_port *p; 220 u_int8_t addr[4]; 221 u_int32_t port; 222 223 switch (op) { 224 225 case SNMP_OP_GETNEXT: 226 if ((p = (struct udp_port *)trans_next_port(my_trans, 227 &value->var, sub)) == NULL) 228 return (SNMP_ERR_NOSUCHNAME); 229 index_append(&value->var, sub, &p->tport.index); 230 break; 231 232 case SNMP_OP_GET: 233 if ((p = (struct udp_port *)trans_find_port(my_trans, 234 &value->var, sub)) == NULL) 235 return (SNMP_ERR_NOSUCHNAME); 236 break; 237 238 case SNMP_OP_SET: 239 p = (struct udp_port *)trans_find_port(my_trans, 240 &value->var, sub); 241 ctx->scratch->int1 = (p != NULL); 242 243 if (which != LEAF_begemotSnmpdPortStatus) 244 abort(); 245 if (!TRUTH_OK(value->v.integer)) 246 return (SNMP_ERR_WRONG_VALUE); 247 248 ctx->scratch->int2 = TRUTH_GET(value->v.integer); 249 250 if (ctx->scratch->int2) { 251 /* open an SNMP port */ 252 if (p != NULL) 253 /* already open - do nothing */ 254 return (SNMP_ERR_NOERROR); 255 256 if (index_decode(&value->var, sub, iidx, addr, &port)) 257 return (SNMP_ERR_NO_CREATION); 258 return (udp_open_port(addr, port, &p)); 259 260 } else { 261 /* close SNMP port - do in commit */ 262 } 263 return (SNMP_ERR_NOERROR); 264 265 case SNMP_OP_ROLLBACK: 266 p = (struct udp_port *)trans_find_port(my_trans, 267 &value->var, sub); 268 if (ctx->scratch->int1 == 0) { 269 /* did not exist */ 270 if (ctx->scratch->int2 == 1) { 271 /* created */ 272 if (p != NULL) 273 udp_close_port(&p->tport); 274 } 275 } 276 return (SNMP_ERR_NOERROR); 277 278 case SNMP_OP_COMMIT: 279 p = (struct udp_port *)trans_find_port(my_trans, 280 &value->var, sub); 281 if (ctx->scratch->int1 == 1) { 282 /* did exist */ 283 if (ctx->scratch->int2 == 0) { 284 /* delete */ 285 if (p != NULL) 286 udp_close_port(&p->tport); 287 } 288 } 289 return (SNMP_ERR_NOERROR); 290 291 default: 292 abort(); 293 } 294 295 /* 296 * Come here to fetch the value 297 */ 298 switch (which) { 299 300 case LEAF_begemotSnmpdPortStatus: 301 value->v.integer = 1; 302 break; 303 304 default: 305 abort(); 306 } 307 308 return (SNMP_ERR_NOERROR); 309 } 310