1 /* $OpenBSD: resolve.c,v 1.79 2017/01/23 16:20:35 naddy Exp $ */ 2 3 /* 4 * Copyright (c) 1998 Per Fogelstrom, Opsycon AB 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 19 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 */ 28 29 #define _DYN_LOADER 30 31 #include <sys/types.h> 32 33 #include <limits.h> 34 #include <nlist.h> 35 #include <link.h> 36 #include "syscall.h" 37 #include "archdep.h" 38 #include "path.h" 39 #include "resolve.h" 40 41 /* substitution types */ 42 typedef enum { 43 SUBST_UNKNOWN, SUBST_ORIGIN, SUBST_OSNAME, SUBST_OSREL, SUBST_PLATFORM 44 } SUBST_TYPES; 45 46 elf_object_t *_dl_objects; 47 elf_object_t *_dl_last_object; 48 elf_object_t *_dl_loading_object; 49 50 /* 51 * Add a new dynamic object to the object list. 52 */ 53 void 54 _dl_add_object(elf_object_t *object) 55 { 56 /* 57 * If a .so is marked nodelete, then the entire load group that it's 58 * in needs to be kept around forever, so add a reference there. 59 * XXX It would be better if we tracked inter-object dependencies 60 * from relocations and didn't leave dangling pointers when a load 61 * group was partially unloaded. That would render this unnecessary. 62 */ 63 if (object->obj_flags & DF_1_NODELETE && 64 (object->load_object->status & STAT_NODELETE) == 0) { 65 DL_DEB(("objname %s is nodelete\n", object->load_name)); 66 object->load_object->opencount++; 67 object->load_object->status |= STAT_NODELETE; 68 } 69 70 /* 71 * if this is a new object, prev will be NULL 72 * != NULL if an object already in the list 73 * prev == NULL for the first item in the list, but that will 74 * be the executable. 75 */ 76 if (object->prev != NULL) 77 return; 78 79 if (_dl_objects == NULL) { /* First object ? */ 80 _dl_last_object = _dl_objects = object; 81 } else { 82 _dl_last_object->next = object; 83 object->prev = _dl_last_object; 84 _dl_last_object = object; 85 } 86 } 87 88 /* 89 * Identify substitution sequence name. 90 */ 91 static int 92 _dl_subst_name(const char *name, size_t siz) { 93 switch (siz) { 94 case 5: 95 if (_dl_strncmp(name, "OSREL", 5) == 0) 96 return SUBST_OSREL; 97 break; 98 case 6: 99 if (_dl_strncmp(name, "ORIGIN", 6) == 0) 100 return SUBST_ORIGIN; 101 if (_dl_strncmp(name, "OSNAME", 6) == 0) 102 return SUBST_OSNAME; 103 break; 104 case 8: 105 if (_dl_strncmp(name, "PLATFORM", 8) == 0) 106 return SUBST_PLATFORM; 107 break; 108 } 109 110 return (SUBST_UNKNOWN); 111 } 112 113 /* 114 * Perform $ORIGIN substitutions on path 115 */ 116 static void 117 _dl_origin_subst_path(elf_object_t *object, const char *origin_path, 118 char **path) 119 { 120 char tmp_path[PATH_MAX]; 121 char *new_path, *tp; 122 const char *pp, *name, *value; 123 static struct utsname uts; 124 size_t value_len; 125 int skip_brace; 126 127 if (uts.sysname[0] == '\0') { 128 if (_dl_uname(&uts) != 0) 129 return; 130 } 131 132 tp = tmp_path; 133 pp = *path; 134 135 while (*pp != '\0' && (tp - tmp_path) < sizeof(tmp_path)) { 136 137 /* copy over chars up to but not including $ */ 138 while (*pp != '\0' && *pp != '$' && 139 (tp - tmp_path) < sizeof(tmp_path)) 140 *tp++ = *pp++; 141 142 /* substitution sequence detected */ 143 if (*pp == '$' && (tp - tmp_path) < sizeof(tmp_path)) { 144 pp++; 145 146 if ((skip_brace = (*pp == '{'))) 147 pp++; 148 149 /* skip over name */ 150 name = pp; 151 while (_dl_isalnum((unsigned char)*pp) || *pp == '_') 152 pp++; 153 154 switch (_dl_subst_name(name, pp - name)) { 155 case SUBST_ORIGIN: 156 value = origin_path; 157 break; 158 case SUBST_OSNAME: 159 value = uts.sysname; 160 break; 161 case SUBST_OSREL: 162 value = uts.release; 163 break; 164 case SUBST_PLATFORM: 165 value = uts.machine; 166 break; 167 default: 168 value = ""; 169 } 170 171 value_len = _dl_strlen(value); 172 if (value_len >= sizeof(tmp_path) - (tp - tmp_path)) 173 return; 174 175 _dl_bcopy(value, tp, value_len); 176 tp += value_len; 177 178 if (skip_brace && *pp == '}') 179 pp++; 180 } 181 } 182 183 /* no substitution made if result exceeds sizeof(tmp_path) */ 184 if (tp - tmp_path >= sizeof(tmp_path)) 185 return; 186 187 /* NULL terminate tmp_path */ 188 *tp = '\0'; 189 190 if (_dl_strcmp(tmp_path, *path) == 0) 191 return; 192 193 new_path = _dl_strdup(tmp_path); 194 if (new_path == NULL) 195 return; 196 197 DL_DEB(("orig_path %s\n", *path)); 198 DL_DEB(("new_path %s\n", new_path)); 199 200 _dl_free(*path); 201 *path = new_path; 202 } 203 204 /* 205 * Determine origin_path from object load_name. The origin_path argument 206 * must refer to a buffer capable of storing at least PATH_MAX characters. 207 * Returns 0 on success. 208 */ 209 static int 210 _dl_origin_path(elf_object_t *object, char *origin_path) 211 { 212 const char *dirname_path = _dl_dirname(object->load_name); 213 214 if (dirname_path == NULL) 215 return -1; 216 217 if (_dl_realpath(dirname_path, origin_path) == NULL) 218 return -1; 219 220 return 0; 221 } 222 223 /* 224 * Perform $ORIGIN substitutions on runpath and rpath 225 */ 226 static void 227 _dl_origin_subst(elf_object_t *object) 228 { 229 char origin_path[PATH_MAX]; 230 char **pp; 231 232 if (_dl_origin_path(object, origin_path) != 0) 233 return; 234 235 /* perform path substitutions on each segment of runpath and rpath */ 236 for (pp = object->runpath; *pp != NULL; pp++) { 237 _dl_origin_subst_path(object, origin_path, pp); 238 } 239 for (pp = object->rpath; *pp != NULL; pp++) { 240 _dl_origin_subst_path(object, origin_path, pp); 241 } 242 } 243 244 /* 245 * Initialize a new dynamic object. 246 */ 247 elf_object_t * 248 _dl_finalize_object(const char *objname, Elf_Dyn *dynp, Elf_Phdr *phdrp, 249 int phdrc, const int objtype, const long lbase, const long obase) 250 { 251 elf_object_t *object; 252 253 #if 0 254 _dl_printf("objname [%s], dynp %p, objtype %x lbase %lx, obase %lx\n", 255 objname, dynp, objtype, lbase, obase); 256 #endif 257 object = _dl_calloc(1, sizeof(elf_object_t)); 258 if (object == NULL) 259 _dl_exit(7); 260 object->prev = object->next = NULL; 261 262 object->load_dyn = dynp; 263 while (dynp->d_tag != DT_NULL) { 264 if (dynp->d_tag < DT_NUM) 265 object->Dyn.info[dynp->d_tag] = dynp->d_un.d_val; 266 else if (dynp->d_tag >= DT_LOPROC && 267 dynp->d_tag < DT_LOPROC + DT_PROCNUM) 268 object->Dyn.info[dynp->d_tag + DT_NUM - DT_LOPROC] = 269 dynp->d_un.d_val; 270 if (dynp->d_tag == DT_TEXTREL) 271 object->dyn.textrel = 1; 272 if (dynp->d_tag == DT_SYMBOLIC) 273 object->dyn.symbolic = 1; 274 if (dynp->d_tag == DT_BIND_NOW) 275 object->obj_flags |= DF_1_NOW; 276 if (dynp->d_tag == DT_FLAGS_1) 277 object->obj_flags |= dynp->d_un.d_val; 278 if (dynp->d_tag == DT_FLAGS) { 279 object->dyn.flags |= dynp->d_un.d_val; 280 if (dynp->d_un.d_val & DF_SYMBOLIC) 281 object->dyn.symbolic = 1; 282 if (dynp->d_un.d_val & DF_ORIGIN) 283 object->obj_flags |= DF_1_ORIGIN; 284 if (dynp->d_un.d_val & DF_BIND_NOW) 285 object->obj_flags |= DF_1_NOW; 286 } 287 if (dynp->d_tag == DT_RELACOUNT) 288 object->relacount = dynp->d_un.d_val; 289 if (dynp->d_tag == DT_RELCOUNT) 290 object->relcount = dynp->d_un.d_val; 291 dynp++; 292 } 293 DL_DEB((" flags %s = 0x%x\n", objname, object->obj_flags )); 294 object->obj_type = objtype; 295 296 if (_dl_loading_object == NULL) { 297 /* 298 * no loading object, object is the loading object, 299 * as it is either executable, or dlopened() 300 */ 301 _dl_loading_object = object; 302 } 303 304 if ((object->obj_flags & DF_1_NOOPEN) != 0 && 305 _dl_loading_object->obj_type == OBJTYPE_DLO && 306 _dl_traceld == NULL) { 307 _dl_free(object); 308 _dl_errno = DL_CANT_LOAD_OBJ; 309 return(NULL); 310 } 311 312 /* 313 * Now relocate all pointer to dynamic info, but only 314 * the ones which have pointer values. 315 */ 316 if (object->Dyn.info[DT_PLTGOT]) 317 object->Dyn.info[DT_PLTGOT] += obase; 318 if (object->Dyn.info[DT_HASH]) 319 object->Dyn.info[DT_HASH] += obase; 320 if (object->Dyn.info[DT_STRTAB]) 321 object->Dyn.info[DT_STRTAB] += obase; 322 if (object->Dyn.info[DT_SYMTAB]) 323 object->Dyn.info[DT_SYMTAB] += obase; 324 if (object->Dyn.info[DT_RELA]) 325 object->Dyn.info[DT_RELA] += obase; 326 if (object->Dyn.info[DT_SONAME]) 327 object->Dyn.info[DT_SONAME] += object->Dyn.info[DT_STRTAB]; 328 if (object->Dyn.info[DT_RPATH]) 329 object->Dyn.info[DT_RPATH] += object->Dyn.info[DT_STRTAB]; 330 if (object->Dyn.info[DT_RUNPATH]) 331 object->Dyn.info[DT_RUNPATH] += object->Dyn.info[DT_STRTAB]; 332 if (object->Dyn.info[DT_REL]) 333 object->Dyn.info[DT_REL] += obase; 334 if (object->Dyn.info[DT_INIT]) 335 object->Dyn.info[DT_INIT] += obase; 336 if (object->Dyn.info[DT_FINI]) 337 object->Dyn.info[DT_FINI] += obase; 338 if (object->Dyn.info[DT_JMPREL]) 339 object->Dyn.info[DT_JMPREL] += obase; 340 if (object->Dyn.info[DT_INIT_ARRAY]) 341 object->Dyn.info[DT_INIT_ARRAY] += obase; 342 if (object->Dyn.info[DT_FINI_ARRAY]) 343 object->Dyn.info[DT_FINI_ARRAY] += obase; 344 if (object->Dyn.info[DT_PREINIT_ARRAY]) 345 object->Dyn.info[DT_PREINIT_ARRAY] += obase; 346 347 if (object->Dyn.info[DT_HASH] != 0) { 348 Elf_Word *hashtab = (Elf_Word *)object->Dyn.info[DT_HASH]; 349 350 object->nbuckets = hashtab[0]; 351 object->nchains = hashtab[1]; 352 object->buckets = hashtab + 2; 353 object->chains = object->buckets + object->nbuckets; 354 } 355 356 object->phdrp = phdrp; 357 object->phdrc = phdrc; 358 object->load_base = lbase; 359 object->obj_base = obase; 360 object->load_name = _dl_strdup(objname); 361 if (object->load_name == NULL) 362 _dl_exit(7); 363 object->load_object = _dl_loading_object; 364 if (object->load_object == object) 365 DL_DEB(("head %s\n", object->load_name)); 366 DL_DEB(("obj %s has %s as head\n", object->load_name, 367 _dl_loading_object->load_name )); 368 object->refcount = 0; 369 TAILQ_INIT(&object->child_list); 370 object->opencount = 0; /* # dlopen() & exe */ 371 object->grprefcount = 0; 372 /* default dev, inode for dlopen-able objects. */ 373 object->dev = 0; 374 object->inode = 0; 375 object->grpsym_gen = 0; 376 TAILQ_INIT(&object->grpsym_list); 377 TAILQ_INIT(&object->grpref_list); 378 379 if (object->dyn.runpath) 380 object->runpath = _dl_split_path(object->dyn.runpath); 381 /* 382 * DT_RPATH is ignored if DT_RUNPATH is present...except in 383 * the exe, whose DT_RPATH is a fallback for libs that don't 384 * use DT_RUNPATH 385 */ 386 if (object->dyn.rpath && (object->runpath == NULL || 387 objtype == OBJTYPE_EXE)) 388 object->rpath = _dl_split_path(object->dyn.rpath); 389 if ((object->obj_flags & DF_1_ORIGIN) && _dl_trust) 390 _dl_origin_subst(object); 391 392 _dl_trace_object_setup(object); 393 394 return (object); 395 } 396 397 static void 398 _dl_tailq_free(struct dep_node *n) 399 { 400 struct dep_node *next; 401 402 while (n != NULL) { 403 next = TAILQ_NEXT(n, next_sib); 404 _dl_free(n); 405 n = next; 406 } 407 } 408 409 static elf_object_t *free_objects; 410 411 void 412 _dl_cleanup_objects() 413 { 414 elf_object_t *nobj, *head; 415 struct dep_node *n, *next; 416 417 n = TAILQ_FIRST(&_dlopened_child_list); 418 while (n != NULL) { 419 next = TAILQ_NEXT(n, next_sib); 420 if (OBJECT_DLREF_CNT(n->data) == 0) { 421 TAILQ_REMOVE(&_dlopened_child_list, n, next_sib); 422 _dl_free(n); 423 } 424 n = next; 425 } 426 427 head = free_objects; 428 free_objects = NULL; 429 while (head != NULL) { 430 _dl_free(head->load_name); 431 _dl_free((char *)head->sod.sod_name); 432 _dl_free_path(head->runpath); 433 _dl_free_path(head->rpath); 434 _dl_tailq_free(TAILQ_FIRST(&head->grpsym_list)); 435 _dl_tailq_free(TAILQ_FIRST(&head->child_list)); 436 _dl_tailq_free(TAILQ_FIRST(&head->grpref_list)); 437 nobj = head->next; 438 _dl_free(head); 439 head = nobj; 440 } 441 } 442 443 void 444 _dl_remove_object(elf_object_t *object) 445 { 446 object->prev->next = object->next; 447 if (object->next) 448 object->next->prev = object->prev; 449 450 if (_dl_last_object == object) 451 _dl_last_object = object->prev; 452 453 object->next = free_objects; 454 free_objects = object; 455 } 456 457 /* 458 * mprotect a segment to the indicated protection. If 'addr' is non-zero, 459 * then it's the start address, else the value of 'start_sym' is the start. 460 * The value of 'end_sym' is the end address. The start is rounded down 461 * and the end is rounded up to page boundaries. Returns 'addr' or the 462 * address of the start symbol. 463 */ 464 void * 465 _dl_protect_segment(elf_object_t *object, Elf_Addr addr, 466 const char *start_sym, const char *end_sym, int prot) 467 { 468 const Elf_Sym *this; 469 Elf_Addr ooff, start, end; 470 471 if (addr == 0 && start_sym[2] == 'g' && 472 (addr = object->relro_addr) != 0) { 473 DL_DEB(("protect start RELRO = 0x%lx in %s\n", 474 addr, object->load_name)); 475 } 476 else if (addr == 0) { 477 this = NULL; 478 ooff = _dl_find_symbol(start_sym, &this, 479 SYM_SEARCH_OBJ | SYM_NOWARNNOTFOUND | SYM_PLT, NULL, 480 object, NULL); 481 /* If not found, nothing to do */ 482 if (this == NULL) { 483 DL_DEB(("protect start \"%s\" not found in %s\n", 484 start_sym, object->load_name)); 485 return (NULL); 486 } 487 addr = ooff + this->st_value; 488 DL_DEB(("protect start \"%s\" to %x = 0x%lx in %s\n", 489 start_sym, prot, addr, object->load_name)); 490 } 491 492 if (object->relro_addr != 0 && start_sym[2] == 'g') { 493 end = object->relro_addr + object->relro_size; 494 DL_DEB(("protect end RELRO = 0x%lx in %s\n", 495 end, object->load_name)); 496 } else { 497 this = NULL; 498 ooff = _dl_find_symbol(end_sym, &this, 499 SYM_SEARCH_OBJ | SYM_NOWARNNOTFOUND | SYM_PLT, NULL, 500 object, NULL); 501 if (this == NULL) { 502 DL_DEB(("protect end \"%s\" not found in %s\n", 503 end_sym, object->load_name)); 504 addr = 0; 505 } else { 506 end = ooff + this->st_value; 507 DL_DEB(("protect end \"%s\" = 0x%lx in %s\n", 508 end_sym, end, object->load_name)); 509 } 510 } 511 512 if (addr != 0 && addr < end) { 513 start = ELF_TRUNC(addr, _dl_pagesz); 514 end = ELF_ROUND(end, _dl_pagesz); 515 _dl_mprotect((void *)start, end - start, prot); 516 } 517 518 return ((void *)addr); 519 } 520 521 522 sym_cache *_dl_symcache; 523 int _dl_symcachestat_hits; 524 int _dl_symcachestat_lookups; 525 526 527 Elf_Addr 528 _dl_find_symbol_bysym(elf_object_t *req_obj, unsigned int symidx, 529 const Elf_Sym **this, int flags, const Elf_Sym *ref_sym, const elf_object_t **pobj) 530 { 531 Elf_Addr ret; 532 const Elf_Sym *sym; 533 const char *symn; 534 const elf_object_t *sobj; 535 536 _dl_symcachestat_lookups ++; 537 if (_dl_symcache != NULL && 538 symidx < req_obj->nchains && 539 _dl_symcache[symidx].obj != NULL && 540 _dl_symcache[symidx].sym != NULL && 541 _dl_symcache[symidx].flags == flags) { 542 543 _dl_symcachestat_hits++; 544 sobj = _dl_symcache[symidx].obj; 545 *this = _dl_symcache[symidx].sym; 546 if (pobj) 547 *pobj = sobj; 548 return sobj->obj_base; 549 } 550 551 sym = req_obj->dyn.symtab; 552 sym += symidx; 553 symn = req_obj->dyn.strtab + sym->st_name; 554 555 ret = _dl_find_symbol(symn, this, flags, ref_sym, req_obj, &sobj); 556 557 if (pobj) 558 *pobj = sobj; 559 560 if (_dl_symcache != NULL && symidx < req_obj->nchains) { 561 #if 0 562 DL_DEB(("cache miss %d %p %p, %p %p %s %s %d %d %s\n", 563 symidx, 564 _dl_symcache[symidx].sym, *this, 565 _dl_symcache[symidx].obj, sobj, sobj->load_name, 566 sobj->dyn.strtab + (*this)->st_name, 567 _dl_symcache[symidx].flags, flags, req_obj->load_name)); 568 #endif 569 570 _dl_symcache[symidx].sym = *this; 571 _dl_symcache[symidx].obj = sobj; 572 _dl_symcache[symidx].flags = flags; 573 } 574 575 return ret; 576 } 577 578 static int 579 _dl_find_symbol_obj(elf_object_t *object, const char *name, unsigned long hash, 580 int flags, const Elf_Sym **this, const Elf_Sym **weak_sym, 581 elf_object_t **weak_object) 582 { 583 const Elf_Sym *symt = object->dyn.symtab; 584 const char *strt = object->dyn.strtab; 585 long si; 586 const char *symn; 587 588 for (si = object->buckets[hash % object->nbuckets]; 589 si != STN_UNDEF; si = object->chains[si]) { 590 const Elf_Sym *sym = symt + si; 591 592 if (sym->st_value == 0) 593 continue; 594 595 if (ELF_ST_TYPE(sym->st_info) != STT_NOTYPE && 596 ELF_ST_TYPE(sym->st_info) != STT_OBJECT && 597 ELF_ST_TYPE(sym->st_info) != STT_FUNC) 598 continue; 599 600 symn = strt + sym->st_name; 601 if (sym != *this && _dl_strcmp(symn, name)) 602 continue; 603 604 /* allow this symbol if we are referring to a function 605 * which has a value, even if section is UNDEF. 606 * this allows &func to refer to PLT as per the 607 * ELF spec. st_value is checked above. 608 * if flags has SYM_PLT set, we must have actual 609 * symbol, so this symbol is skipped. 610 */ 611 if (sym->st_shndx == SHN_UNDEF) { 612 if ((flags & SYM_PLT) || sym->st_value == 0 || 613 ELF_ST_TYPE(sym->st_info) != STT_FUNC) 614 continue; 615 } 616 617 if (ELF_ST_BIND(sym->st_info) == STB_GLOBAL) { 618 *this = sym; 619 return 1; 620 } else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { 621 if (!*weak_sym) { 622 *weak_sym = sym; 623 *weak_object = object; 624 } 625 } 626 } 627 return 0; 628 } 629 630 Elf_Addr 631 _dl_find_symbol(const char *name, const Elf_Sym **this, 632 int flags, const Elf_Sym *ref_sym, elf_object_t *req_obj, 633 const elf_object_t **pobj) 634 { 635 const Elf_Sym *weak_sym = NULL; 636 unsigned long h = 0; 637 const char *p = name; 638 elf_object_t *object = NULL, *weak_object = NULL; 639 int found = 0; 640 struct dep_node *n, *m; 641 642 643 while (*p) { 644 unsigned long g; 645 h = (h << 4) + *p++; 646 if ((g = h & 0xf0000000)) 647 h ^= g >> 24; 648 h &= ~g; 649 } 650 651 if (req_obj->dyn.symbolic) 652 if (_dl_find_symbol_obj(req_obj, name, h, flags, this, &weak_sym, 653 &weak_object)) { 654 object = req_obj; 655 found = 1; 656 goto found; 657 } 658 659 if (flags & SYM_SEARCH_OBJ) { 660 if (_dl_find_symbol_obj(req_obj, name, h, flags, this, 661 &weak_sym, &weak_object)) { 662 object = req_obj; 663 found = 1; 664 } 665 } else if (flags & SYM_DLSYM) { 666 if (_dl_find_symbol_obj(req_obj, name, h, flags, this, 667 &weak_sym, &weak_object)) { 668 object = req_obj; 669 found = 1; 670 } 671 if (weak_object != NULL && found == 0) { 672 object=weak_object; 673 *this = weak_sym; 674 found = 1; 675 } 676 /* search dlopened obj and all children */ 677 678 if (found == 0) { 679 TAILQ_FOREACH(n, &req_obj->load_object->grpsym_list, 680 next_sib) { 681 if (_dl_find_symbol_obj(n->data, name, h, 682 flags, this, 683 &weak_sym, &weak_object)) { 684 object = n->data; 685 found = 1; 686 break; 687 } 688 } 689 } 690 } else { 691 int skip = 0; 692 693 if ((flags & SYM_SEARCH_SELF) || (flags & SYM_SEARCH_NEXT)) 694 skip = 1; 695 696 /* 697 * search dlopened objects: global or req_obj == dlopened_obj 698 * and and it's children 699 */ 700 TAILQ_FOREACH(n, &_dlopened_child_list, next_sib) { 701 if (((n->data->obj_flags & DF_1_GLOBAL) == 0) && 702 (n->data != req_obj->load_object)) 703 continue; 704 705 TAILQ_FOREACH(m, &n->data->grpsym_list, next_sib) { 706 if (skip == 1) { 707 if (m->data == req_obj) { 708 skip = 0; 709 if (flags & SYM_SEARCH_NEXT) 710 continue; 711 } else 712 continue; 713 } 714 if ((flags & SYM_SEARCH_OTHER) && 715 (m->data == req_obj)) 716 continue; 717 if (_dl_find_symbol_obj(m->data, name, h, flags, 718 this, &weak_sym, &weak_object)) { 719 object = m->data; 720 found = 1; 721 goto found; 722 } 723 } 724 } 725 } 726 727 found: 728 if (weak_object != NULL && found == 0) { 729 object=weak_object; 730 *this = weak_sym; 731 found = 1; 732 } 733 734 735 if (found == 0) { 736 if ((ref_sym == NULL || 737 (ELF_ST_BIND(ref_sym->st_info) != STB_WEAK)) && 738 (flags & SYM_WARNNOTFOUND)) 739 _dl_printf("%s:%s: undefined symbol '%s'\n", 740 __progname, req_obj->load_name, name); 741 return (0); 742 } 743 744 if (ref_sym != NULL && ref_sym->st_size != 0 && 745 (ref_sym->st_size != (*this)->st_size) && 746 (ELF_ST_TYPE((*this)->st_info) != STT_FUNC) ) { 747 _dl_printf("%s:%s: %s : WARNING: " 748 "symbol(%s) size mismatch, relink your program\n", 749 __progname, req_obj->load_name, object->load_name, name); 750 } 751 752 if (pobj) 753 *pobj = object; 754 755 return (object->obj_base); 756 } 757 758 void 759 _dl_debug_state(void) 760 { 761 /* Debugger stub */ 762 } 763