dyndb.c revision 1.1.1.6
1 /* $NetBSD: dyndb.c,v 1.1.1.6 2021/02/19 16:37:12 christos Exp $ */ 2 3 /* 4 * Copyright (C) Internet Systems Consortium, Inc. ("ISC") 5 * 6 * This Source Code Form is subject to the terms of the Mozilla Public 7 * License, v. 2.0. If a copy of the MPL was not distributed with this 8 * file, you can obtain one at https://mozilla.org/MPL/2.0/. 9 * 10 * See the COPYRIGHT file distributed with this work for additional 11 * information regarding copyright ownership. 12 */ 13 14 #if HAVE_DLFCN_H 15 #include <dlfcn.h> 16 #elif _WIN32 17 #include <windows.h> 18 #endif /* if HAVE_DLFCN_H */ 19 20 #include <string.h> 21 22 #include <isc/buffer.h> 23 #include <isc/mem.h> 24 #include <isc/mutex.h> 25 #include <isc/once.h> 26 #include <isc/region.h> 27 #include <isc/result.h> 28 #include <isc/task.h> 29 #include <isc/types.h> 30 #include <isc/util.h> 31 32 #include <dns/dyndb.h> 33 #include <dns/log.h> 34 #include <dns/types.h> 35 #include <dns/view.h> 36 #include <dns/zone.h> 37 38 #define CHECK(op) \ 39 do { \ 40 result = (op); \ 41 if (result != ISC_R_SUCCESS) \ 42 goto cleanup; \ 43 } while (0) 44 45 typedef struct dyndb_implementation dyndb_implementation_t; 46 struct dyndb_implementation { 47 isc_mem_t *mctx; 48 void *handle; 49 dns_dyndb_register_t *register_func; 50 dns_dyndb_destroy_t *destroy_func; 51 char *name; 52 void *inst; 53 LINK(dyndb_implementation_t) link; 54 }; 55 56 /* 57 * List of dyndb implementations. Locked by dyndb_lock. 58 * 59 * These are stored here so they can be cleaned up on shutdown. 60 * (The order in which they are stored is not important.) 61 */ 62 static LIST(dyndb_implementation_t) dyndb_implementations; 63 64 /* Locks dyndb_implementations. */ 65 static isc_mutex_t dyndb_lock; 66 static isc_once_t once = ISC_ONCE_INIT; 67 68 static void 69 dyndb_initialize(void) { 70 isc_mutex_init(&dyndb_lock); 71 INIT_LIST(dyndb_implementations); 72 } 73 74 static dyndb_implementation_t * 75 impfind(const char *name) { 76 dyndb_implementation_t *imp; 77 78 for (imp = ISC_LIST_HEAD(dyndb_implementations); imp != NULL; 79 imp = ISC_LIST_NEXT(imp, link)) 80 { 81 if (strcasecmp(name, imp->name) == 0) { 82 return (imp); 83 } 84 } 85 return (NULL); 86 } 87 88 #if HAVE_DLFCN_H && HAVE_DLOPEN 89 static isc_result_t 90 load_symbol(void *handle, const char *filename, const char *symbol_name, 91 void **symbolp) { 92 const char *errmsg; 93 void *symbol; 94 95 REQUIRE(handle != NULL); 96 REQUIRE(symbolp != NULL && *symbolp == NULL); 97 98 symbol = dlsym(handle, symbol_name); 99 if (symbol == NULL) { 100 errmsg = dlerror(); 101 if (errmsg == NULL) { 102 errmsg = "returned function pointer is NULL"; 103 } 104 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 105 DNS_LOGMODULE_DYNDB, ISC_LOG_ERROR, 106 "failed to lookup symbol %s in " 107 "dyndb module '%s': %s", 108 symbol_name, filename, errmsg); 109 return (ISC_R_FAILURE); 110 } 111 dlerror(); 112 113 *symbolp = symbol; 114 115 return (ISC_R_SUCCESS); 116 } 117 118 static isc_result_t 119 load_library(isc_mem_t *mctx, const char *filename, const char *instname, 120 dyndb_implementation_t **impp) { 121 isc_result_t result; 122 void *handle = NULL; 123 dyndb_implementation_t *imp = NULL; 124 dns_dyndb_register_t *register_func = NULL; 125 dns_dyndb_destroy_t *destroy_func = NULL; 126 dns_dyndb_version_t *version_func = NULL; 127 int version, flags; 128 129 REQUIRE(impp != NULL && *impp == NULL); 130 131 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DYNDB, 132 ISC_LOG_INFO, "loading DynDB instance '%s' driver '%s'", 133 instname, filename); 134 135 flags = RTLD_NOW | RTLD_LOCAL; 136 #if defined(RTLD_DEEPBIND) && !__SANITIZE_ADDRESS__ 137 flags |= RTLD_DEEPBIND; 138 #endif /* if defined(RTLD_DEEPBIND) && !__SANITIZE_ADDRESS__ */ 139 140 handle = dlopen(filename, flags); 141 if (handle == NULL) { 142 CHECK(ISC_R_FAILURE); 143 } 144 145 /* Clear dlerror */ 146 dlerror(); 147 148 CHECK(load_symbol(handle, filename, "dyndb_version", 149 (void **)&version_func)); 150 151 version = version_func(NULL); 152 if (version < (DNS_DYNDB_VERSION - DNS_DYNDB_AGE) || 153 version > DNS_DYNDB_VERSION) 154 { 155 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 156 DNS_LOGMODULE_DYNDB, ISC_LOG_ERROR, 157 "driver API version mismatch: %d/%d", version, 158 DNS_DYNDB_VERSION); 159 CHECK(ISC_R_FAILURE); 160 } 161 162 CHECK(load_symbol(handle, filename, "dyndb_init", 163 (void **)®ister_func)); 164 CHECK(load_symbol(handle, filename, "dyndb_destroy", 165 (void **)&destroy_func)); 166 167 imp = isc_mem_get(mctx, sizeof(dyndb_implementation_t)); 168 169 imp->mctx = NULL; 170 isc_mem_attach(mctx, &imp->mctx); 171 imp->handle = handle; 172 imp->register_func = register_func; 173 imp->destroy_func = destroy_func; 174 imp->name = isc_mem_strdup(mctx, instname); 175 176 imp->inst = NULL; 177 INIT_LINK(imp, link); 178 179 *impp = imp; 180 imp = NULL; 181 182 cleanup: 183 if (result != ISC_R_SUCCESS) { 184 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 185 DNS_LOGMODULE_DYNDB, ISC_LOG_ERROR, 186 "failed to dynamically load instance '%s' " 187 "driver '%s': %s (%s)", 188 instname, filename, dlerror(), 189 isc_result_totext(result)); 190 } 191 if (imp != NULL) { 192 isc_mem_putanddetach(&imp->mctx, imp, 193 sizeof(dyndb_implementation_t)); 194 } 195 if (result != ISC_R_SUCCESS && handle != NULL) { 196 dlclose(handle); 197 } 198 199 return (result); 200 } 201 202 static void 203 unload_library(dyndb_implementation_t **impp) { 204 dyndb_implementation_t *imp; 205 206 REQUIRE(impp != NULL && *impp != NULL); 207 208 imp = *impp; 209 *impp = NULL; 210 211 isc_mem_free(imp->mctx, imp->name); 212 isc_mem_putanddetach(&imp->mctx, imp, sizeof(dyndb_implementation_t)); 213 } 214 #elif _WIN32 215 static isc_result_t 216 load_symbol(HMODULE handle, const char *filename, const char *symbol_name, 217 void **symbolp) { 218 void *symbol; 219 220 REQUIRE(handle != NULL); 221 REQUIRE(symbolp != NULL && *symbolp == NULL); 222 223 symbol = GetProcAddress(handle, symbol_name); 224 if (symbol == NULL) { 225 int errstatus = GetLastError(); 226 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 227 DNS_LOGMODULE_DYNDB, ISC_LOG_ERROR, 228 "failed to lookup symbol %s in " 229 "dyndb module '%s': %d", 230 symbol_name, filename, errstatus); 231 return (ISC_R_FAILURE); 232 } 233 234 *symbolp = symbol; 235 236 return (ISC_R_SUCCESS); 237 } 238 239 static isc_result_t 240 load_library(isc_mem_t *mctx, const char *filename, const char *instname, 241 dyndb_implementation_t **impp) { 242 isc_result_t result; 243 HMODULE handle; 244 dyndb_implementation_t *imp = NULL; 245 dns_dyndb_register_t *register_func = NULL; 246 dns_dyndb_destroy_t *destroy_func = NULL; 247 dns_dyndb_version_t *version_func = NULL; 248 int version; 249 250 REQUIRE(impp != NULL && *impp == NULL); 251 252 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DYNDB, 253 ISC_LOG_INFO, "loading DynDB instance '%s' driver '%s'", 254 instname, filename); 255 256 handle = LoadLibraryA(filename); 257 if (handle == NULL) { 258 CHECK(ISC_R_FAILURE); 259 } 260 261 CHECK(load_symbol(handle, filename, "dyndb_version", 262 (void **)&version_func)); 263 264 version = version_func(NULL); 265 if (version < (DNS_DYNDB_VERSION - DNS_DYNDB_AGE) || 266 version > DNS_DYNDB_VERSION) 267 { 268 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 269 DNS_LOGMODULE_DYNDB, ISC_LOG_ERROR, 270 "driver API version mismatch: %d/%d", version, 271 DNS_DYNDB_VERSION); 272 CHECK(ISC_R_FAILURE); 273 } 274 275 CHECK(load_symbol(handle, filename, "dyndb_init", 276 (void **)®ister_func)); 277 CHECK(load_symbol(handle, filename, "dyndb_destroy", 278 (void **)&destroy_func)); 279 280 imp = isc_mem_get(mctx, sizeof(dyndb_implementation_t)); 281 282 imp->mctx = NULL; 283 isc_mem_attach(mctx, &imp->mctx); 284 imp->handle = handle; 285 imp->register_func = register_func; 286 imp->destroy_func = destroy_func; 287 imp->name = isc_mem_strdup(mctx, instname); 288 289 imp->inst = NULL; 290 INIT_LINK(imp, link); 291 292 *impp = imp; 293 imp = NULL; 294 295 cleanup: 296 if (result != ISC_R_SUCCESS) { 297 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 298 DNS_LOGMODULE_DYNDB, ISC_LOG_ERROR, 299 "failed to dynamically load instance '%s' " 300 "driver '%s': %d (%s)", 301 instname, filename, GetLastError(), 302 isc_result_totext(result)); 303 } 304 if (imp != NULL) { 305 isc_mem_putanddetach(&imp->mctx, imp, 306 sizeof(dyndb_implementation_t)); 307 } 308 if (result != ISC_R_SUCCESS && handle != NULL) { 309 FreeLibrary(handle); 310 } 311 312 return (result); 313 } 314 315 static void 316 unload_library(dyndb_implementation_t **impp) { 317 dyndb_implementation_t *imp; 318 319 REQUIRE(impp != NULL && *impp != NULL); 320 321 imp = *impp; 322 *impp = NULL; 323 324 isc_mem_free(imp->mctx, imp->name); 325 isc_mem_putanddetach(&imp->mctx, imp, sizeof(dyndb_implementation_t)); 326 } 327 #else /* HAVE_DLFCN_H || _WIN32 */ 328 static isc_result_t 329 load_library(isc_mem_t *mctx, const char *filename, const char *instname, 330 dyndb_implementation_t **impp) { 331 UNUSED(mctx); 332 UNUSED(filename); 333 UNUSED(instname); 334 UNUSED(impp); 335 336 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DYNDB, 337 ISC_LOG_ERROR, 338 "dynamic database support is not implemented"); 339 340 return (ISC_R_NOTIMPLEMENTED); 341 } 342 343 static void 344 unload_library(dyndb_implementation_t **impp) { 345 UNUSED(impp); 346 } 347 #endif /* HAVE_DLFCN_H */ 348 349 isc_result_t 350 dns_dyndb_load(const char *libname, const char *name, const char *parameters, 351 const char *file, unsigned long line, isc_mem_t *mctx, 352 const dns_dyndbctx_t *dctx) { 353 isc_result_t result; 354 dyndb_implementation_t *implementation = NULL; 355 356 REQUIRE(DNS_DYNDBCTX_VALID(dctx)); 357 REQUIRE(name != NULL); 358 359 RUNTIME_CHECK(isc_once_do(&once, dyndb_initialize) == ISC_R_SUCCESS); 360 361 LOCK(&dyndb_lock); 362 363 /* duplicate instance names are not allowed */ 364 if (impfind(name) != NULL) { 365 CHECK(ISC_R_EXISTS); 366 } 367 368 CHECK(load_library(mctx, libname, name, &implementation)); 369 CHECK(implementation->register_func(mctx, name, parameters, file, line, 370 dctx, &implementation->inst)); 371 372 APPEND(dyndb_implementations, implementation, link); 373 result = ISC_R_SUCCESS; 374 375 cleanup: 376 if (result != ISC_R_SUCCESS) { 377 if (implementation != NULL) { 378 unload_library(&implementation); 379 } 380 } 381 382 UNLOCK(&dyndb_lock); 383 return (result); 384 } 385 386 void 387 dns_dyndb_cleanup(bool exiting) { 388 dyndb_implementation_t *elem; 389 dyndb_implementation_t *prev; 390 391 RUNTIME_CHECK(isc_once_do(&once, dyndb_initialize) == ISC_R_SUCCESS); 392 393 LOCK(&dyndb_lock); 394 elem = TAIL(dyndb_implementations); 395 while (elem != NULL) { 396 prev = PREV(elem, link); 397 UNLINK(dyndb_implementations, elem, link); 398 isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, 399 DNS_LOGMODULE_DYNDB, ISC_LOG_INFO, 400 "unloading DynDB instance '%s'", elem->name); 401 elem->destroy_func(&elem->inst); 402 ENSURE(elem->inst == NULL); 403 unload_library(&elem); 404 elem = prev; 405 } 406 UNLOCK(&dyndb_lock); 407 408 if (exiting) { 409 isc_mutex_destroy(&dyndb_lock); 410 } 411 } 412 413 isc_result_t 414 dns_dyndb_createctx(isc_mem_t *mctx, const void *hashinit, isc_log_t *lctx, 415 dns_view_t *view, dns_zonemgr_t *zmgr, isc_task_t *task, 416 isc_timermgr_t *tmgr, dns_dyndbctx_t **dctxp) { 417 dns_dyndbctx_t *dctx; 418 419 REQUIRE(dctxp != NULL && *dctxp == NULL); 420 421 dctx = isc_mem_get(mctx, sizeof(*dctx)); 422 423 memset(dctx, 0, sizeof(*dctx)); 424 if (view != NULL) { 425 dns_view_attach(view, &dctx->view); 426 } 427 if (zmgr != NULL) { 428 dns_zonemgr_attach(zmgr, &dctx->zmgr); 429 } 430 if (task != NULL) { 431 isc_task_attach(task, &dctx->task); 432 } 433 dctx->timermgr = tmgr; 434 dctx->hashinit = hashinit; 435 dctx->lctx = lctx; 436 dctx->refvar = &isc_bind9; 437 438 isc_mem_attach(mctx, &dctx->mctx); 439 dctx->magic = DNS_DYNDBCTX_MAGIC; 440 441 *dctxp = dctx; 442 443 return (ISC_R_SUCCESS); 444 } 445 446 void 447 dns_dyndb_destroyctx(dns_dyndbctx_t **dctxp) { 448 dns_dyndbctx_t *dctx; 449 450 REQUIRE(dctxp != NULL && DNS_DYNDBCTX_VALID(*dctxp)); 451 452 dctx = *dctxp; 453 *dctxp = NULL; 454 455 dctx->magic = 0; 456 457 if (dctx->view != NULL) { 458 dns_view_detach(&dctx->view); 459 } 460 if (dctx->zmgr != NULL) { 461 dns_zonemgr_detach(&dctx->zmgr); 462 } 463 if (dctx->task != NULL) { 464 isc_task_detach(&dctx->task); 465 } 466 dctx->timermgr = NULL; 467 dctx->lctx = NULL; 468 469 isc_mem_putanddetach(&dctx->mctx, dctx, sizeof(*dctx)); 470 } 471
Indexes created Tue Apr 28 00:22:25 UTC 2026