snmpmod.h revision 156066
1/* 2 * Copyright (c) 2001-2003 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/snmpmod.h,v 1.32 2006/02/14 09:04:20 brandt_h Exp $ 30 * 31 * SNMP daemon data and functions exported to modules. 32 */ 33#ifndef snmpmod_h_ 34#define snmpmod_h_ 35 36#include <sys/types.h> 37#include <sys/socket.h> 38#include <net/if.h> 39#include <netinet/in.h> 40#include "asn1.h" 41#include "snmp.h" 42#include "snmpagent.h" 43 44#define MAX_MOD_ARGS 16 45 46/* 47 * These macros help to handle object lists for SNMP tables. They use 48 * tail queues to hold the objects in ascending order in the list. 49 * ordering can be done either on an integer/unsigned field, an asn_oid 50 * or an ordering function. 51 */ 52#define INSERT_OBJECT_OID_LINK_INDEX(PTR, LIST, LINK, INDEX) do { \ 53 __typeof (PTR) _lelem; \ 54 \ 55 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 56 if (asn_compare_oid(&_lelem->INDEX, &(PTR)->INDEX) > 0) \ 57 break; \ 58 if (_lelem == NULL) \ 59 TAILQ_INSERT_TAIL((LIST), (PTR), LINK); \ 60 else \ 61 TAILQ_INSERT_BEFORE(_lelem, (PTR), LINK); \ 62 } while (0) 63 64#define INSERT_OBJECT_INT_LINK_INDEX(PTR, LIST, LINK, INDEX) do { \ 65 __typeof (PTR) _lelem; \ 66 \ 67 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 68 if ((asn_subid_t)_lelem->INDEX > (asn_subid_t)(PTR)->INDEX)\ 69 break; \ 70 if (_lelem == NULL) \ 71 TAILQ_INSERT_TAIL((LIST), (PTR), LINK); \ 72 else \ 73 TAILQ_INSERT_BEFORE(_lelem, (PTR), LINK); \ 74 } while (0) 75 76#define INSERT_OBJECT_FUNC_LINK(PTR, LIST, LINK, FUNC) do { \ 77 __typeof (PTR) _lelem; \ 78 \ 79 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 80 if ((FUNC)(_lelem, (PTR)) > 0) \ 81 break; \ 82 if (_lelem == NULL) \ 83 TAILQ_INSERT_TAIL((LIST), (PTR), LINK); \ 84 else \ 85 TAILQ_INSERT_BEFORE(_lelem, (PTR), LINK); \ 86 } while (0) 87 88#define INSERT_OBJECT_FUNC_LINK_REV(PTR, LIST, HEAD, LINK, FUNC) do { \ 89 __typeof (PTR) _lelem; \ 90 \ 91 TAILQ_FOREACH_REVERSE(_lelem, (LIST), HEAD, LINK) \ 92 if ((FUNC)(_lelem, (PTR)) < 0) \ 93 break; \ 94 if (_lelem == NULL) \ 95 TAILQ_INSERT_HEAD((LIST), (PTR), LINK); \ 96 else \ 97 TAILQ_INSERT_AFTER((LIST), _lelem, (PTR), LINK); \ 98 } while (0) 99 100#define FIND_OBJECT_OID_LINK_INDEX(LIST, OID, SUB, LINK, INDEX) ({ \ 101 __typeof (TAILQ_FIRST(LIST)) _lelem; \ 102 \ 103 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 104 if (index_compare(OID, SUB, &_lelem->INDEX) == 0) \ 105 break; \ 106 (_lelem); \ 107 }) 108 109#define NEXT_OBJECT_OID_LINK_INDEX(LIST, OID, SUB, LINK, INDEX) ({ \ 110 __typeof (TAILQ_FIRST(LIST)) _lelem; \ 111 \ 112 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 113 if (index_compare(OID, SUB, &_lelem->INDEX) < 0) \ 114 break; \ 115 (_lelem); \ 116 }) 117 118#define FIND_OBJECT_INT_LINK_INDEX(LIST, OID, SUB, LINK, INDEX) ({ \ 119 __typeof (TAILQ_FIRST(LIST)) _lelem; \ 120 \ 121 if ((OID)->len - SUB != 1) \ 122 _lelem = NULL; \ 123 else \ 124 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 125 if ((OID)->subs[SUB] == (asn_subid_t)_lelem->INDEX)\ 126 break; \ 127 (_lelem); \ 128 }) 129 130#define NEXT_OBJECT_INT_LINK_INDEX(LIST, OID, SUB, LINK, INDEX) ({ \ 131 __typeof (TAILQ_FIRST(LIST)) _lelem; \ 132 \ 133 if ((OID)->len - SUB == 0) \ 134 _lelem = TAILQ_FIRST(LIST); \ 135 else \ 136 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 137 if ((OID)->subs[SUB] < (asn_subid_t)_lelem->INDEX)\ 138 break; \ 139 (_lelem); \ 140 }) 141 142#define FIND_OBJECT_FUNC_LINK(LIST, OID, SUB, LINK, FUNC) ({ \ 143 __typeof (TAILQ_FIRST(LIST)) _lelem; \ 144 \ 145 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 146 if ((FUNC)(OID, SUB, _lelem) == 0) \ 147 break; \ 148 (_lelem); \ 149 }) 150 151#define NEXT_OBJECT_FUNC_LINK(LIST, OID, SUB, LINK, FUNC) ({ \ 152 __typeof (TAILQ_FIRST(LIST)) _lelem; \ 153 \ 154 TAILQ_FOREACH(_lelem, (LIST), LINK) \ 155 if ((FUNC)(OID, SUB, _lelem) < 0) \ 156 break; \ 157 (_lelem); \ 158 }) 159 160/* 161 * Macros for the case where the index field is called 'index' 162 */ 163#define INSERT_OBJECT_OID_LINK(PTR, LIST, LINK) \ 164 INSERT_OBJECT_OID_LINK_INDEX(PTR, LIST, LINK, index) 165 166#define INSERT_OBJECT_INT_LINK(PTR, LIST, LINK) do { \ 167 INSERT_OBJECT_INT_LINK_INDEX(PTR, LIST, LINK, index) 168 169#define FIND_OBJECT_OID_LINK(LIST, OID, SUB, LINK) \ 170 FIND_OBJECT_OID_LINK_INDEX(LIST, OID, SUB, LINK, index) 171 172#define NEXT_OBJECT_OID_LINK(LIST, OID, SUB, LINK) \ 173 NEXT_OBJECT_OID_LINK_INDEX(LIST, OID, SUB, LINK, index) 174 175#define FIND_OBJECT_INT_LINK(LIST, OID, SUB, LINK) \ 176 FIND_OBJECT_INT_LINK_INDEX(LIST, OID, SUB, LINK, index) 177 178#define NEXT_OBJECT_INT_LINK(LIST, OID, SUB, LINK) \ 179 NEXT_OBJECT_INT_LINK_INDEX(LIST, OID, SUB, LINK, index) 180 181/* 182 * Macros for the case where the index field is called 'index' and the 183 * link field 'link'. 184 */ 185#define INSERT_OBJECT_OID(PTR, LIST) \ 186 INSERT_OBJECT_OID_LINK_INDEX(PTR, LIST, link, index) 187 188#define INSERT_OBJECT_INT(PTR, LIST) \ 189 INSERT_OBJECT_INT_LINK_INDEX(PTR, LIST, link, index) 190 191#define INSERT_OBJECT_FUNC_REV(PTR, LIST, HEAD, FUNC) \ 192 INSERT_OBJECT_FUNC_LINK_REV(PTR, LIST, HEAD, link, FUNC) 193 194#define FIND_OBJECT_OID(LIST, OID, SUB) \ 195 FIND_OBJECT_OID_LINK_INDEX(LIST, OID, SUB, link, index) 196 197#define FIND_OBJECT_INT(LIST, OID, SUB) \ 198 FIND_OBJECT_INT_LINK_INDEX(LIST, OID, SUB, link, index) 199 200#define FIND_OBJECT_FUNC(LIST, OID, SUB, FUNC) \ 201 FIND_OBJECT_FUNC_LINK(LIST, OID, SUB, link, FUNC) 202 203#define NEXT_OBJECT_OID(LIST, OID, SUB) \ 204 NEXT_OBJECT_OID_LINK_INDEX(LIST, OID, SUB, link, index) 205 206#define NEXT_OBJECT_INT(LIST, OID, SUB) \ 207 NEXT_OBJECT_INT_LINK_INDEX(LIST, OID, SUB, link, index) 208 209#define NEXT_OBJECT_FUNC(LIST, OID, SUB, FUNC) \ 210 NEXT_OBJECT_FUNC_LINK(LIST, OID, SUB, link, FUNC) 211 212struct lmodule; 213 214/* The tick when the program was started. This is the absolute time of 215 * the start in 100th of a second. */ 216extern uint64_t start_tick; 217 218/* The tick when the current packet was received. This is the absolute 219 * time in 100th of second. */ 220extern uint64_t this_tick; 221 222/* Get the current absolute time in 100th of a second. */ 223uint64_t get_ticks(void); 224 225/* 226 * Return code for proxy function 227 */ 228enum snmpd_proxy_err { 229 /* proxy code will process the PDU */ 230 SNMPD_PROXY_OK, 231 /* proxy code does not process PDU */ 232 SNMPD_PROXY_REJ, 233 /* drop this PDU */ 234 SNMPD_PROXY_DROP, 235 /* drop because of bad community */ 236 SNMPD_PROXY_BADCOMM, 237 /* drop because of bad community use */ 238 SNMPD_PROXY_BADCOMMUSE 239}; 240 241/* 242 * Input handling 243 */ 244enum snmpd_input_err { 245 /* proceed with packet */ 246 SNMPD_INPUT_OK, 247 /* fatal error in packet, ignore it */ 248 SNMPD_INPUT_FAILED, 249 /* value encoding has wrong length in a SET operation */ 250 SNMPD_INPUT_VALBADLEN, 251 /* value encoding is out of range */ 252 SNMPD_INPUT_VALRANGE, 253 /* value has bad encoding */ 254 SNMPD_INPUT_VALBADENC, 255 /* need more data (truncated packet) */ 256 SNMPD_INPUT_TRUNC, 257 /* unknown community */ 258 SNMPD_INPUT_BAD_COMM, 259}; 260 261/* 262 * Every loadable module must have one of this structures with 263 * the external name 'config'. 264 */ 265struct snmp_module { 266 /* a comment describing what this module implements */ 267 const char *comment; 268 269 /* the initialization function */ 270 int (*init)(struct lmodule *, int argc, char *argv[]); 271 272 /* the finalisation function */ 273 int (*fini)(void); 274 275 /* the idle function */ 276 void (*idle)(void); 277 278 /* the dump function */ 279 void (*dump)(void); 280 281 /* re-configuration function */ 282 void (*config)(void); 283 284 /* start operation */ 285 void (*start)(void); 286 287 /* proxy a PDU */ 288 enum snmpd_proxy_err (*proxy)(struct snmp_pdu *, void *, 289 const struct asn_oid *, const struct sockaddr *, socklen_t, 290 enum snmpd_input_err, int32_t, int); 291 292 /* the tree this module is going to server */ 293 const struct snmp_node *tree; 294 u_int tree_size; 295 296 /* function called, when another module was unloaded/loaded */ 297 void (*loading)(const struct lmodule *, int); 298}; 299 300/* 301 * Stuff exported to modules 302 */ 303 304/* 305 * The system group. 306 */ 307struct systemg { 308 u_char *descr; 309 struct asn_oid object_id; 310 u_char *contact; 311 u_char *name; 312 u_char *location; 313 u_int32_t services; 314 u_int32_t or_last_change; 315}; 316extern struct systemg systemg; 317 318/* 319 * Community support. 320 * 321 * We have 2 fixed communities for SNMP read and write access. Modules 322 * can create their communities dynamically. They are deleted automatically 323 * if the module is unloaded. 324 */ 325#define COMM_INITIALIZE 0 326#define COMM_READ 1 327#define COMM_WRITE 2 328 329u_int comm_define(u_int, const char *descr, struct lmodule *, const char *str); 330const char * comm_string(u_int); 331 332/* community for current packet */ 333extern u_int community; 334 335/* 336 * Well known OIDs 337 */ 338extern const struct asn_oid oid_zeroDotZero; 339 340/* 341 * Request ID ranges. 342 * 343 * A module can request a range of request ids and associate them with a 344 * type field. All ranges are deleted if a module is unloaded. 345 */ 346u_int reqid_allocate(int size, struct lmodule *); 347int32_t reqid_next(u_int type); 348int32_t reqid_base(u_int type); 349int reqid_istype(int32_t reqid, u_int type); 350u_int reqid_type(int32_t reqid); 351 352/* 353 * Timers. 354 */ 355void *timer_start(u_int, void (*)(void *), void *, struct lmodule *); 356void *timer_start_repeat(u_int, u_int, void (*)(void *), void *, 357 struct lmodule *); 358void timer_stop(void *); 359 360/* 361 * File descriptors 362 */ 363void *fd_select(int, void (*)(int, void *), void *, struct lmodule *); 364void fd_deselect(void *); 365void fd_suspend(void *); 366int fd_resume(void *); 367 368/* 369 * Object resources 370 */ 371u_int or_register(const struct asn_oid *, const char *, struct lmodule *); 372void or_unregister(u_int); 373 374/* 375 * Buffers 376 */ 377void *buf_alloc(int tx); 378size_t buf_size(int tx); 379 380/* decode PDU and find community */ 381enum snmpd_input_err snmp_input_start(const u_char *, size_t, const char *, 382 struct snmp_pdu *, int32_t *, size_t *); 383 384/* process the pdu. returns either _OK or _FAILED */ 385enum snmpd_input_err snmp_input_finish(struct snmp_pdu *, const u_char *, 386 size_t, u_char *, size_t *, const char *, enum snmpd_input_err, int32_t, 387 void *); 388 389void snmp_output(struct snmp_pdu *, u_char *, size_t *, const char *); 390void snmp_send_port(void *, const struct asn_oid *, struct snmp_pdu *, 391 const struct sockaddr *, socklen_t); 392 393/* sending traps */ 394void snmp_send_trap(const struct asn_oid *, ...); 395 396/* 397 * Action support 398 */ 399int string_save(struct snmp_value *, struct snmp_context *, ssize_t, u_char **); 400void string_commit(struct snmp_context *); 401void string_rollback(struct snmp_context *, u_char **); 402int string_get(struct snmp_value *, const u_char *, ssize_t); 403int string_get_max(struct snmp_value *, const u_char *, ssize_t, size_t); 404void string_free(struct snmp_context *); 405 406int ip_save(struct snmp_value *, struct snmp_context *, u_char *); 407void ip_rollback(struct snmp_context *, u_char *); 408void ip_commit(struct snmp_context *); 409int ip_get(struct snmp_value *, u_char *); 410 411int oid_save(struct snmp_value *, struct snmp_context *, struct asn_oid *); 412void oid_rollback(struct snmp_context *, struct asn_oid *); 413void oid_commit(struct snmp_context *); 414int oid_get(struct snmp_value *, const struct asn_oid *); 415 416int index_decode(const struct asn_oid *oid, u_int sub, u_int code, ...); 417int index_compare(const struct asn_oid *, u_int, const struct asn_oid *); 418int index_compare_off(const struct asn_oid *, u_int, const struct asn_oid *, 419 u_int); 420void index_append(struct asn_oid *, u_int, const struct asn_oid *); 421void index_append_off(struct asn_oid *, u_int, const struct asn_oid *, u_int); 422 423#endif 424