1/*- 2 * SPDX-License-Identifier: BSD-4-Clause 3 * 4 * Copyright (c) 1995 5 * Bill Paul <wpaul@ctr.columbia.edu>. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Bill Paul. 18 * 4. Neither the name of the author nor the names of any co-contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35#include <sys/cdefs.h> 36__FBSDID("$FreeBSD$"); 37 38#include <db.h> 39#include <errno.h> 40#include <fcntl.h> 41#include <limits.h> 42#include <paths.h> 43#include <stdio.h> 44#include <stdlib.h> 45#include <string.h> 46#include <unistd.h> 47#include <sys/stat.h> 48#include <sys/param.h> 49#include <rpcsvc/yp.h> 50#include "yp_extern.h" 51 52int ypdb_debug = 0; 53enum ypstat yp_errno = YP_TRUE; 54 55#define PERM_SECURE (S_IRUSR|S_IWUSR) 56HASHINFO openinfo = { 57 4096, /* bsize */ 58 32, /* ffactor */ 59 256, /* nelem */ 60 2048 * 512, /* cachesize */ 61 NULL, /* hash */ 62 0, /* lorder */ 63}; 64 65#ifdef DB_CACHE 66#include <sys/queue.h> 67 68#ifndef MAXDBS 69#define MAXDBS 20 70#endif 71 72static int numdbs = 0; 73 74struct dbent { 75 DB *dbp; 76 char *name; 77 char *key; 78 int size; 79 int flags; 80}; 81 82static TAILQ_HEAD(circlehead, circleq_entry) qhead; 83 84struct circleq_entry { 85 struct dbent *dbptr; 86 TAILQ_ENTRY(circleq_entry) links; 87}; 88 89/* 90 * Initialize the circular queue. 91 */ 92void 93yp_init_dbs(void) 94{ 95 TAILQ_INIT(&qhead); 96 return; 97} 98 99/* 100 * Dynamically allocate an entry for the circular queue. 101 * Return a NULL pointer on failure. 102 */ 103static struct circleq_entry * 104yp_malloc_qent(void) 105{ 106 register struct circleq_entry *q; 107 108 q = malloc(sizeof(struct circleq_entry)); 109 if (q == NULL) { 110 yp_error("failed to malloc() circleq entry"); 111 return(NULL); 112 } 113 bzero((char *)q, sizeof(struct circleq_entry)); 114 q->dbptr = malloc(sizeof(struct dbent)); 115 if (q->dbptr == NULL) { 116 yp_error("failed to malloc() circleq entry"); 117 free(q); 118 return(NULL); 119 } 120 bzero((char *)q->dbptr, sizeof(struct dbent)); 121 122 return(q); 123} 124 125/* 126 * Free a previously allocated circular queue 127 * entry. 128 */ 129static void 130yp_free_qent(struct circleq_entry *q) 131{ 132 /* 133 * First, close the database. In theory, this is also 134 * supposed to free the resources allocated by the DB 135 * package, including the memory pointed to by q->dbptr->key. 136 * This means we don't have to free q->dbptr->key here. 137 */ 138 if (q->dbptr->dbp) { 139 (void)(q->dbptr->dbp->close)(q->dbptr->dbp); 140 q->dbptr->dbp = NULL; 141 } 142 /* 143 * Then free the database name, which was strdup()'ed. 144 */ 145 free(q->dbptr->name); 146 147 /* 148 * Free the rest of the dbent struct. 149 */ 150 free(q->dbptr); 151 q->dbptr = NULL; 152 153 /* 154 * Free the circleq struct. 155 */ 156 free(q); 157 q = NULL; 158 159 return; 160} 161 162/* 163 * Zorch a single entry in the dbent queue and release 164 * all its resources. (This always removes the last entry 165 * in the queue.) 166 */ 167static void 168yp_flush(void) 169{ 170 register struct circleq_entry *qptr; 171 172 qptr = TAILQ_LAST(&qhead, circlehead); 173 TAILQ_REMOVE(&qhead, qptr, links); 174 yp_free_qent(qptr); 175 numdbs--; 176 177 return; 178} 179 180/* 181 * Close all databases, erase all database names and empty the queue. 182 */ 183void 184yp_flush_all(void) 185{ 186 register struct circleq_entry *qptr; 187 188 while (!TAILQ_EMPTY(&qhead)) { 189 qptr = TAILQ_FIRST(&qhead); /* save this */ 190 TAILQ_REMOVE(&qhead, qptr, links); 191 yp_free_qent(qptr); 192 } 193 numdbs = 0; 194 195 return; 196} 197 198static char *inter_string = "YP_INTERDOMAIN"; 199static char *secure_string = "YP_SECURE"; 200static int inter_sz = sizeof("YP_INTERDOMAIN") - 1; 201static int secure_sz = sizeof("YP_SECURE") - 1; 202 203static int 204yp_setflags(DB *dbp) 205{ 206 DBT key = { NULL, 0 }, data = { NULL, 0 }; 207 int flags = 0; 208 209 key.data = inter_string; 210 key.size = inter_sz; 211 212 if (!(dbp->get)(dbp, &key, &data, 0)) 213 flags |= YP_INTERDOMAIN; 214 215 key.data = secure_string; 216 key.size = secure_sz; 217 218 if (!(dbp->get)(dbp, &key, &data, 0)) 219 flags |= YP_SECURE; 220 221 return(flags); 222} 223 224int 225yp_testflag(char *map, char *domain, int flag) 226{ 227 char buf[MAXPATHLEN + 2]; 228 register struct circleq_entry *qptr; 229 230 if (map == NULL || domain == NULL) 231 return(0); 232 233 strcpy(buf, domain); 234 strcat(buf, "/"); 235 strcat(buf, map); 236 237 TAILQ_FOREACH(qptr, &qhead, links) { 238 if (!strcmp(qptr->dbptr->name, buf)) { 239 if (qptr->dbptr->flags & flag) 240 return(1); 241 else 242 return(0); 243 } 244 } 245 246 if (yp_open_db_cache(domain, map, NULL, 0) == NULL) 247 return(0); 248 249 if (TAILQ_FIRST(&qhead)->dbptr->flags & flag) 250 return(1); 251 252 return(0); 253} 254 255/* 256 * Add a DB handle and database name to the cache. We only maintain 257 * fixed number of entries in the cache, so if we're asked to store 258 * a new entry when all our slots are already filled, we have to kick 259 * out the entry in the last slot to make room. 260 */ 261static int 262yp_cache_db(DB *dbp, char *name, int size) 263{ 264 register struct circleq_entry *qptr; 265 266 if (numdbs == MAXDBS) { 267 if (ypdb_debug) 268 yp_error("queue overflow -- releasing last slot"); 269 yp_flush(); 270 } 271 272 /* 273 * Allocate a new queue entry. 274 */ 275 276 if ((qptr = yp_malloc_qent()) == NULL) { 277 yp_error("failed to allocate a new cache entry"); 278 return(1); 279 } 280 281 qptr->dbptr->dbp = dbp; 282 qptr->dbptr->name = strdup(name); 283 qptr->dbptr->size = size; 284 qptr->dbptr->key = NULL; 285 286 qptr->dbptr->flags = yp_setflags(dbp); 287 288 TAILQ_INSERT_HEAD(&qhead, qptr, links); 289 numdbs++; 290 291 return(0); 292} 293 294/* 295 * Search the list for a database matching 'name.' If we find it, 296 * move it to the head of the list and return its DB handle. If 297 * not, just fail: yp_open_db_cache() will subsequently try to open 298 * the database itself and call yp_cache_db() to add it to the 299 * list. 300 * 301 * The search works like this: 302 * 303 * - The caller specifies the name of a database to locate. We try to 304 * find an entry in our queue with a matching name. 305 * 306 * - If the caller doesn't specify a key or size, we assume that the 307 * first entry that we encounter with a matching name is returned. 308 * This will result in matches regardless of the key/size values 309 * stored in the queue entry. 310 * 311 * - If the caller also specifies a key and length, we check to see 312 * if the key and length saved in the queue entry also matches. 313 * This lets us return a DB handle that's already positioned at the 314 * correct location within a database. 315 * 316 * - Once we have a match, it gets migrated to the top of the queue 317 * so that it will be easier to find if another request for 318 * the same database comes in later. 319 */ 320static DB * 321yp_find_db(const char *name, const char *key, int size) 322{ 323 register struct circleq_entry *qptr; 324 325 TAILQ_FOREACH(qptr, &qhead, links) { 326 if (!strcmp(qptr->dbptr->name, name)) { 327 if (size) { 328 if (size != qptr->dbptr->size || 329 strncmp(qptr->dbptr->key, key, size)) 330 continue; 331 } else { 332 if (qptr->dbptr->size) 333 continue; 334 } 335 if (qptr != TAILQ_FIRST(&qhead)) { 336 TAILQ_REMOVE(&qhead, qptr, links); 337 TAILQ_INSERT_HEAD(&qhead, qptr, links); 338 } 339 return(qptr->dbptr->dbp); 340 } 341 } 342 343 return(NULL); 344} 345 346/* 347 * Open a DB database and cache the handle for later use. We first 348 * check the cache to see if the required database is already open. 349 * If so, we fetch the handle from the cache. If not, we try to open 350 * the database and save the handle in the cache for later use. 351 */ 352DB * 353yp_open_db_cache(const char *domain, const char *map, const char *key, 354 const int size) 355{ 356 DB *dbp = NULL; 357 char buf[MAXPATHLEN + 2]; 358/* 359 snprintf(buf, sizeof(buf), "%s/%s", domain, map); 360*/ 361 yp_errno = YP_TRUE; 362 363 strcpy(buf, domain); 364 strcat(buf, "/"); 365 strcat(buf, map); 366 367 if ((dbp = yp_find_db(buf, key, size)) != NULL) { 368 return(dbp); 369 } else { 370 if ((dbp = yp_open_db(domain, map)) != NULL) { 371 if (yp_cache_db(dbp, buf, size)) { 372 (void)(dbp->close)(dbp); 373 yp_errno = YP_YPERR; 374 return(NULL); 375 } 376 } 377 } 378 379 return (dbp); 380} 381#endif 382 383/* 384 * Open a DB database. 385 */ 386DB * 387yp_open_db(const char *domain, const char *map) 388{ 389 DB *dbp = NULL; 390 char buf[MAXPATHLEN + 2]; 391 392 yp_errno = YP_TRUE; 393 394 if (map[0] == '.' || strchr(map, '/')) { 395 yp_errno = YP_BADARGS; 396 return (NULL); 397 } 398 399#ifdef DB_CACHE 400 if (yp_validdomain(domain)) { 401 yp_errno = YP_NODOM; 402 return(NULL); 403 } 404#endif 405 snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, domain, map); 406 407#ifdef DB_CACHE 408again: 409#endif 410 dbp = dbopen(buf, O_RDONLY, PERM_SECURE, DB_HASH, NULL); 411 412 if (dbp == NULL) { 413 switch (errno) { 414#ifdef DB_CACHE 415 case ENFILE: 416 /* 417 * We ran out of file descriptors. Nuke an 418 * open one and try again. 419 */ 420 yp_error("ran out of file descriptors"); 421 yp_flush(); 422 goto again; 423 break; 424#endif 425 case ENOENT: 426 yp_errno = YP_NOMAP; 427 break; 428 case EFTYPE: 429 yp_errno = YP_BADDB; 430 break; 431 default: 432 yp_errno = YP_YPERR; 433 break; 434 } 435 } 436 437 return (dbp); 438} 439 440/* 441 * Database access routines. 442 * 443 * - yp_get_record(): retrieve an arbitrary key/data pair given one key 444 * to match against. 445 * 446 * - yp_first_record(): retrieve first key/data base in a database. 447 * 448 * - yp_next_record(): retrieve key/data pair that sequentially follows 449 * the supplied key value in the database. 450 */ 451 452#ifdef DB_CACHE 453int 454yp_get_record(DB *dbp, const DBT *key, DBT *data, int allow) 455#else 456int 457yp_get_record(const char *domain, const char *map, 458 const DBT *key, DBT *data, int allow) 459#endif 460{ 461#ifndef DB_CACHE 462 DB *dbp; 463#endif 464 int rval = 0; 465#ifndef DB_CACHE 466 static unsigned char buf[YPMAXRECORD]; 467#endif 468 469 if (ypdb_debug) 470 yp_error("looking up key [%.*s]", 471 (int)key->size, (char *)key->data); 472 473 /* 474 * Avoid passing back magic "YP_*" entries unless 475 * the caller specifically requested them by setting 476 * the 'allow' flag. 477 */ 478 if (!allow && !strncmp(key->data, "YP_", 3)) 479 return(YP_NOKEY); 480 481#ifndef DB_CACHE 482 if ((dbp = yp_open_db(domain, map)) == NULL) { 483 return(yp_errno); 484 } 485#endif 486 487 if ((rval = (dbp->get)(dbp, key, data, 0)) != 0) { 488#ifdef DB_CACHE 489 TAILQ_FIRST(&qhead)->dbptr->size = 0; 490#else 491 (void)(dbp->close)(dbp); 492#endif 493 if (rval == 1) 494 return(YP_NOKEY); 495 else 496 return(YP_BADDB); 497 } 498 499 if (ypdb_debug) 500 yp_error("result of lookup: key: [%.*s] data: [%.*s]", 501 (int)key->size, (char *)key->data, 502 (int)data->size, (char *)data->data); 503 504#ifdef DB_CACHE 505 if (TAILQ_FIRST(&qhead)->dbptr->size) { 506 TAILQ_FIRST(&qhead)->dbptr->key = ""; 507 TAILQ_FIRST(&qhead)->dbptr->size = 0; 508 } 509#else 510 bcopy(data->data, &buf, data->size); 511 data->data = &buf; 512 (void)(dbp->close)(dbp); 513#endif 514 515 return(YP_TRUE); 516} 517 518int 519yp_first_record(const DB *dbp, DBT *key, DBT *data, int allow) 520{ 521 int rval; 522#ifndef DB_CACHE 523 static unsigned char buf[YPMAXRECORD]; 524#endif 525 526 if (ypdb_debug) 527 yp_error("retrieving first key in map"); 528 529 if ((rval = (dbp->seq)(dbp,key,data,R_FIRST)) != 0) { 530#ifdef DB_CACHE 531 TAILQ_FIRST(&qhead)->dbptr->size = 0; 532#endif 533 if (rval == 1) 534 return(YP_NOKEY); 535 else 536 return(YP_BADDB); 537 } 538 539 /* Avoid passing back magic "YP_*" records. */ 540 while (!strncmp(key->data, "YP_", 3) && !allow) { 541 if ((rval = (dbp->seq)(dbp,key,data,R_NEXT)) != 0) { 542#ifdef DB_CACHE 543 TAILQ_FIRST(&qhead)->dbptr->size = 0; 544#endif 545 if (rval == 1) 546 return(YP_NOKEY); 547 else 548 return(YP_BADDB); 549 } 550 } 551 552 if (ypdb_debug) 553 yp_error("result of lookup: key: [%.*s] data: [%.*s]", 554 (int)key->size, (char *)key->data, 555 (int)data->size, (char *)data->data); 556 557#ifdef DB_CACHE 558 if (TAILQ_FIRST(&qhead)->dbptr->size) { 559 TAILQ_FIRST(&qhead)->dbptr->key = key->data; 560 TAILQ_FIRST(&qhead)->dbptr->size = key->size; 561 } 562#else 563 bcopy(data->data, &buf, data->size); 564 data->data = &buf; 565#endif 566 567 return(YP_TRUE); 568} 569 570int 571yp_next_record(const DB *dbp, DBT *key, DBT *data, int all, int allow) 572{ 573 static DBT lkey = { NULL, 0 }; 574 static DBT ldata = { NULL, 0 }; 575 int rval; 576#ifndef DB_CACHE 577 static unsigned char keybuf[YPMAXRECORD]; 578 static unsigned char datbuf[YPMAXRECORD]; 579#endif 580 581 if (key == NULL || !key->size || key->data == NULL) { 582 rval = yp_first_record(dbp,key,data,allow); 583 if (rval == YP_NOKEY) 584 return(YP_NOMORE); 585 else { 586#ifdef DB_CACHE 587 TAILQ_FIRST(&qhead)->dbptr->key = key->data; 588 TAILQ_FIRST(&qhead)->dbptr->size = key->size; 589#endif 590 return(rval); 591 } 592 } 593 594 if (ypdb_debug) 595 yp_error("retrieving next key, previous was: [%.*s]", 596 (int)key->size, (char *)key->data); 597 598 if (!all) { 599#ifdef DB_CACHE 600 if (TAILQ_FIRST(&qhead)->dbptr->key == NULL) { 601#endif 602 (dbp->seq)(dbp,&lkey,&ldata,R_FIRST); 603 while (key->size != lkey.size || 604 strncmp(key->data, lkey.data, 605 (int)key->size)) 606 if ((dbp->seq)(dbp,&lkey,&ldata,R_NEXT)) { 607#ifdef DB_CACHE 608 TAILQ_FIRST(&qhead)->dbptr->size = 0; 609#endif 610 return(YP_NOKEY); 611 } 612 613#ifdef DB_CACHE 614 } 615#endif 616 } 617 618 if ((dbp->seq)(dbp,key,data,R_NEXT)) { 619#ifdef DB_CACHE 620 TAILQ_FIRST(&qhead)->dbptr->size = 0; 621#endif 622 return(YP_NOMORE); 623 } 624 625 /* Avoid passing back magic "YP_*" records. */ 626 while (!strncmp(key->data, "YP_", 3) && !allow) 627 if ((dbp->seq)(dbp,key,data,R_NEXT)) { 628#ifdef DB_CACHE 629 TAILQ_FIRST(&qhead)->dbptr->size = 0; 630#endif 631 return(YP_NOMORE); 632 } 633 634 if (ypdb_debug) 635 yp_error("result of lookup: key: [%.*s] data: [%.*s]", 636 (int)key->size, (char *)key->data, 637 (int)data->size, (char *)data->data); 638 639#ifdef DB_CACHE 640 if (TAILQ_FIRST(&qhead)->dbptr->size) { 641 TAILQ_FIRST(&qhead)->dbptr->key = key->data; 642 TAILQ_FIRST(&qhead)->dbptr->size = key->size; 643 } 644#else 645 bcopy(key->data, &keybuf, key->size); 646 lkey.data = &keybuf; 647 lkey.size = key->size; 648 bcopy(data->data, &datbuf, data->size); 649 data->data = &datbuf; 650#endif 651 652 return(YP_TRUE); 653} 654 655#ifdef DB_CACHE 656/* 657 * Database glue functions. 658 */ 659 660static DB *yp_currmap_db = NULL; 661static int yp_allow_db = 0; 662 663ypstat 664yp_select_map(char *map, char *domain, keydat *key, int allow) 665{ 666 if (key == NULL) 667 yp_currmap_db = yp_open_db_cache(domain, map, NULL, 0); 668 else 669 yp_currmap_db = yp_open_db_cache(domain, map, 670 key->keydat_val, 671 key->keydat_len); 672 673 yp_allow_db = allow; 674 return(yp_errno); 675} 676 677ypstat 678yp_getbykey(keydat *key, valdat *val) 679{ 680 DBT db_key = { NULL, 0 }, db_val = { NULL, 0 }; 681 ypstat rval; 682 683 db_key.data = key->keydat_val; 684 db_key.size = key->keydat_len; 685 686 rval = yp_get_record(yp_currmap_db, 687 &db_key, &db_val, yp_allow_db); 688 689 if (rval == YP_TRUE) { 690 val->valdat_val = db_val.data; 691 val->valdat_len = db_val.size; 692 } 693 694 return(rval); 695} 696 697ypstat 698yp_firstbykey(keydat *key, valdat *val) 699{ 700 DBT db_key = { NULL, 0 }, db_val = { NULL, 0 }; 701 ypstat rval; 702 703 rval = yp_first_record(yp_currmap_db, &db_key, &db_val, yp_allow_db); 704 705 if (rval == YP_TRUE) { 706 key->keydat_val = db_key.data; 707 key->keydat_len = db_key.size; 708 val->valdat_val = db_val.data; 709 val->valdat_len = db_val.size; 710 } 711 712 return(rval); 713} 714 715ypstat 716yp_nextbykey(keydat *key, valdat *val) 717{ 718 DBT db_key = { NULL, 0 }, db_val = { NULL, 0 }; 719 ypstat rval; 720 721 db_key.data = key->keydat_val; 722 db_key.size = key->keydat_len; 723 724 rval = yp_next_record(yp_currmap_db, &db_key, &db_val, 0, yp_allow_db); 725 726 if (rval == YP_TRUE) { 727 key->keydat_val = db_key.data; 728 key->keydat_len = db_key.size; 729 val->valdat_val = db_val.data; 730 val->valdat_len = db_val.size; 731 } 732 733 return(rval); 734} 735#endif 736