1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * Copyright (c) 1988 AT&T 29 * All Rights Reserved 30 */ 31 32 /* 33 * Object file dependent support for ELF objects. 34 */ 35 36 #include <stdio.h> 37 #include <sys/procfs.h> 38 #include <sys/mman.h> 39 #include <sys/debug.h> 40 #include <string.h> 41 #include <limits.h> 42 #include <dlfcn.h> 43 #include <debug.h> 44 #include <conv.h> 45 #include "_rtld.h" 46 #include "_audit.h" 47 #include "_elf.h" 48 #include "_inline.h" 49 #include "msg.h" 50 51 /* 52 * Default and secure dependency search paths. 53 */ 54 static Spath_defn _elf_def_dirs[] = { 55 #if defined(_ELF64) 56 { MSG_ORIG(MSG_PTH_LIB_64), MSG_PTH_LIB_64_SIZE }, 57 { MSG_ORIG(MSG_PTH_USRLIB_64), MSG_PTH_USRLIB_64_SIZE }, 58 #else 59 { MSG_ORIG(MSG_PTH_LIB), MSG_PTH_LIB_SIZE }, 60 { MSG_ORIG(MSG_PTH_USRLIB), MSG_PTH_USRLIB_SIZE }, 61 #endif 62 { 0, 0 } 63 }; 64 65 static Spath_defn _elf_sec_dirs[] = { 66 #if defined(_ELF64) 67 { MSG_ORIG(MSG_PTH_LIBSE_64), MSG_PTH_LIBSE_64_SIZE }, 68 { MSG_ORIG(MSG_PTH_USRLIBSE_64), MSG_PTH_USRLIBSE_64_SIZE }, 69 #else 70 { MSG_ORIG(MSG_PTH_LIBSE), MSG_PTH_LIBSE_SIZE }, 71 { MSG_ORIG(MSG_PTH_USRLIBSE), MSG_PTH_USRLIBSE_SIZE }, 72 #endif 73 { 0, 0 } 74 }; 75 76 Alist *elf_def_dirs = NULL; 77 Alist *elf_sec_dirs = NULL; 78 79 /* 80 * Defines for local functions. 81 */ 82 static void elf_dladdr(ulong_t, Rt_map *, Dl_info *, void **, int); 83 static Addr elf_entry_point(void); 84 static int elf_fix_name(const char *, Rt_map *, Alist **, Aliste, uint_t); 85 static Alist **elf_get_def_dirs(void); 86 static Alist **elf_get_sec_dirs(void); 87 static char *elf_get_so(const char *, const char *, size_t, size_t); 88 static int elf_needed(Lm_list *, Aliste, Rt_map *, int *); 89 90 /* 91 * Functions and data accessed through indirect pointers. 92 */ 93 Fct elf_fct = { 94 elf_verify, 95 elf_new_lmp, 96 elf_entry_point, 97 elf_needed, 98 lookup_sym, 99 elf_reloc, 100 elf_get_def_dirs, 101 elf_get_sec_dirs, 102 elf_fix_name, 103 elf_get_so, 104 elf_dladdr, 105 dlsym_handle 106 }; 107 108 /* 109 * Default and secure dependency search paths. 110 */ 111 static Alist ** 112 elf_get_def_dirs() 113 { 114 if (elf_def_dirs == NULL) 115 set_dirs(&elf_def_dirs, _elf_def_dirs, LA_SER_DEFAULT); 116 return (&elf_def_dirs); 117 } 118 119 static Alist ** 120 elf_get_sec_dirs() 121 { 122 if (elf_sec_dirs == NULL) 123 set_dirs(&elf_sec_dirs, _elf_sec_dirs, LA_SER_SECURE); 124 return (&elf_sec_dirs); 125 } 126 127 /* 128 * Redefine NEEDED name if necessary. 129 */ 130 static int 131 elf_fix_name(const char *name, Rt_map *clmp, Alist **alpp, Aliste alni, 132 uint_t orig) 133 { 134 /* 135 * For ABI compliance, if we are asked for ld.so.1, then really give 136 * them libsys.so.1 (the SONAME of libsys.so.1 is ld.so.1). 137 */ 138 if (((*name == '/') && 139 /* BEGIN CSTYLED */ 140 #if defined(_ELF64) 141 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD_64)) == 0)) || 142 #else 143 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD)) == 0)) || 144 #endif 145 (strcmp(name, MSG_ORIG(MSG_FIL_RTLD)) == 0)) { 146 /* END CSTYLED */ 147 Pdesc *pdp; 148 149 DBG_CALL(Dbg_file_fixname(LIST(clmp), name, 150 MSG_ORIG(MSG_PTH_LIBSYS))); 151 if ((pdp = alist_append(alpp, 0, sizeof (Pdesc), alni)) == NULL) 152 return (0); 153 154 pdp->pd_pname = (char *)MSG_ORIG(MSG_PTH_LIBSYS); 155 pdp->pd_plen = MSG_PTH_LIBSYS_SIZE; 156 pdp->pd_flags = PD_FLG_PNSLASH; 157 158 return (1); 159 } 160 161 return (expand_paths(clmp, name, alpp, alni, orig, 0)); 162 } 163 164 /* 165 * Determine whether this object requires any hardware or software capabilities. 166 */ 167 static int 168 elf_cap_check(Fdesc *fdp, Ehdr *ehdr, Rej_desc *rej) 169 { 170 Phdr *phdr; 171 int cnt; 172 173 /* LINTED */ 174 phdr = (Phdr *)((char *)ehdr + ehdr->e_phoff); 175 for (cnt = 0; cnt < ehdr->e_phnum; cnt++, phdr++) { 176 Cap *cptr; 177 178 if (phdr->p_type != PT_SUNWCAP) 179 continue; 180 181 /* LINTED */ 182 cptr = (Cap *)((char *)ehdr + phdr->p_offset); 183 while (cptr->c_tag != CA_SUNW_NULL) { 184 if (cptr->c_tag == CA_SUNW_HW_1) { 185 /* 186 * Verify the hardware capabilities. 187 */ 188 if (hwcap_check(cptr->c_un.c_val, rej) == 0) 189 return (0); 190 191 /* 192 * Retain this hardware capabilities value for 193 * possible later inspection should this object 194 * be processed as a filtee. 195 */ 196 fdp->fd_hwcap = cptr->c_un.c_val; 197 } 198 if (cptr->c_tag == CA_SUNW_SF_1) { 199 /* 200 * Verify the software capabilities. 201 */ 202 if (sfcap_check(cptr->c_un.c_val, rej) == 0) 203 return (0); 204 } 205 cptr++; 206 } 207 } 208 return (1); 209 } 210 211 /* 212 * Determine if we have been given an ELF file and if so determine if the file 213 * is compatible. Returns 1 if true, else 0 and sets the reject descriptor 214 * with associated error information. 215 */ 216 Fct * 217 elf_verify(caddr_t addr, size_t size, Fdesc *fdp, const char *name, 218 Rej_desc *rej) 219 { 220 Ehdr *ehdr; 221 char *caddr = (char *)addr; 222 223 /* 224 * Determine if we're an elf file. If not simply return, we don't set 225 * any rejection information as this test allows use to scroll through 226 * the objects we support (ELF, AOUT). 227 */ 228 if (size < sizeof (Ehdr) || 229 caddr[EI_MAG0] != ELFMAG0 || 230 caddr[EI_MAG1] != ELFMAG1 || 231 caddr[EI_MAG2] != ELFMAG2 || 232 caddr[EI_MAG3] != ELFMAG3) { 233 return (NULL); 234 } 235 236 /* 237 * Check class and encoding. 238 */ 239 /* LINTED */ 240 ehdr = (Ehdr *)addr; 241 if (ehdr->e_ident[EI_CLASS] != M_CLASS) { 242 rej->rej_type = SGS_REJ_CLASS; 243 rej->rej_info = (uint_t)ehdr->e_ident[EI_CLASS]; 244 return (NULL); 245 } 246 if (ehdr->e_ident[EI_DATA] != M_DATA) { 247 rej->rej_type = SGS_REJ_DATA; 248 rej->rej_info = (uint_t)ehdr->e_ident[EI_DATA]; 249 return (NULL); 250 } 251 if ((ehdr->e_type != ET_REL) && (ehdr->e_type != ET_EXEC) && 252 (ehdr->e_type != ET_DYN)) { 253 rej->rej_type = SGS_REJ_TYPE; 254 rej->rej_info = (uint_t)ehdr->e_type; 255 return (NULL); 256 } 257 258 /* 259 * Verify ELF version. 260 */ 261 if (ehdr->e_version > EV_CURRENT) { 262 rej->rej_type = SGS_REJ_VERSION; 263 rej->rej_info = (uint_t)ehdr->e_version; 264 return (NULL); 265 } 266 267 /* 268 * Verify machine specific flags. 269 */ 270 if (elf_mach_flags_check(rej, ehdr) == 0) 271 return (NULL); 272 273 /* 274 * Verify any hardware/software capability requirements. Note, if this 275 * object is an explicitly defined shared object under inspection by 276 * ldd(1), and contains an incompatible hardware capabilities 277 * requirement, then inform the user, but continue processing. 278 */ 279 if (elf_cap_check(fdp, ehdr, rej) == 0) { 280 Rt_map *lmp = lml_main.lm_head; 281 282 if ((lml_main.lm_flags & LML_FLG_TRC_LDDSTUB) && 283 (lmp != NULL) && (FLAGS1(lmp) & FL1_RT_LDDSTUB) && 284 (NEXT(lmp) == NULL)) { 285 const char *fmt; 286 287 if (rej->rej_type == SGS_REJ_HWCAP_1) 288 fmt = MSG_INTL(MSG_LDD_GEN_HWCAP_1); 289 else 290 fmt = MSG_INTL(MSG_LDD_GEN_SFCAP_1); 291 (void) printf(fmt, name, rej->rej_str); 292 return (&elf_fct); 293 } 294 return (NULL); 295 } 296 return (&elf_fct); 297 } 298 299 /* 300 * The runtime linker employs lazy loading to provide the libraries needed for 301 * debugging, preloading .o's and dldump(). As these are seldom used, the 302 * standard startup of ld.so.1 doesn't initialize all the information necessary 303 * to perform plt relocation on ld.so.1's link-map. The first time lazy loading 304 * is called we get here to perform these initializations: 305 * 306 * o elf_needed() is called to set up the DYNINFO() indexes for each lazy 307 * dependency. Typically, for all other objects, this is called during 308 * analyze_so(), but as ld.so.1 is set-contained we skip this processing. 309 * 310 * o For intel, ld.so.1's JMPSLOT relocations need relative updates. These 311 * are by default skipped thus delaying all relative relocation processing 312 * on every invocation of ld.so.1. 313 */ 314 int 315 elf_rtld_load() 316 { 317 Lm_list *lml = &lml_rtld; 318 Rt_map *lmp = lml->lm_head; 319 320 if (lml->lm_flags & LML_FLG_PLTREL) 321 return (1); 322 323 /* 324 * As we need to refer to the DYNINFO() information, insure that it has 325 * been initialized. 326 */ 327 if (elf_needed(lml, ALIST_OFF_DATA, lmp, NULL) == 0) 328 return (0); 329 330 #if defined(__i386) 331 /* 332 * This is a kludge to give ld.so.1 a performance benefit on i386. 333 * It's based around two factors. 334 * 335 * o JMPSLOT relocations (PLT's) actually need a relative relocation 336 * applied to the GOT entry so that they can find PLT0. 337 * 338 * o ld.so.1 does not exercise *any* PLT's before it has made a call 339 * to elf_lazy_load(). This is because all dynamic dependencies 340 * are recorded as lazy dependencies. 341 */ 342 (void) elf_reloc_relative_count((ulong_t)JMPREL(lmp), 343 (ulong_t)(PLTRELSZ(lmp) / RELENT(lmp)), (ulong_t)RELENT(lmp), 344 (ulong_t)ADDR(lmp), lmp, NULL); 345 #endif 346 347 lml->lm_flags |= LML_FLG_PLTREL; 348 return (1); 349 } 350 351 /* 352 * Lazy load an object. 353 */ 354 Rt_map * 355 elf_lazy_load(Rt_map *clmp, Slookup *slp, uint_t ndx, const char *sym, 356 int *in_nfavl) 357 { 358 Alist *palp = NULL; 359 Rt_map *nlmp, *hlmp; 360 Dyninfo *dip = &DYNINFO(clmp)[ndx], *pdip; 361 uint_t flags = 0; 362 const char *name; 363 Lm_list *lml = LIST(clmp); 364 Aliste lmco; 365 366 /* 367 * If this dependency has already been processed, we're done. 368 */ 369 if (((nlmp = (Rt_map *)dip->di_info) != NULL) || 370 (dip->di_flags & FLG_DI_LDD_DONE)) 371 return (nlmp); 372 373 /* 374 * If we're running under ldd(1), indicate that this dependency has been 375 * processed (see test above). It doesn't matter whether the object is 376 * successfully loaded or not, this flag simply ensures that we don't 377 * repeatedly attempt to load an object that has already failed to load. 378 * To do so would create multiple failure diagnostics for the same 379 * object under ldd(1). 380 */ 381 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 382 dip->di_flags |= FLG_DI_LDD_DONE; 383 384 /* 385 * Determine the initial dependency name. 386 */ 387 name = STRTAB(clmp) + DYN(clmp)[ndx].d_un.d_val; 388 DBG_CALL(Dbg_file_lazyload(clmp, name, sym)); 389 390 /* 391 * If this object needs to establish its own group, make sure a handle 392 * is created. 393 */ 394 if (dip->di_flags & FLG_DI_GROUP) 395 flags |= (FLG_RT_SETGROUP | FLG_RT_HANDLE); 396 397 /* 398 * Lazy dependencies are identified as DT_NEEDED entries with a 399 * DF_P1_LAZYLOAD flag in the previous DT_POSFLAG_1 element. The 400 * dynamic information element that corresponds to the DT_POSFLAG_1 401 * entry is free, and thus used to store the present entrance 402 * identifier. This identifier is used to prevent multiple attempts to 403 * load a failed lazy loadable dependency within the same runtime linker 404 * operation. However, future attempts to reload this dependency are 405 * still possible. 406 */ 407 if (ndx && (pdip = dip - 1) && (pdip->di_flags & FLG_DI_POSFLAG1)) 408 pdip->di_info = (void *)slp->sl_id; 409 410 /* 411 * Expand the requested name if necessary. 412 */ 413 if (elf_fix_name(name, clmp, &palp, AL_CNT_NEEDED, 0) == 0) 414 return (NULL); 415 416 /* 417 * Provided the object on the head of the link-map has completed its 418 * relocation, create a new link-map control list for this request. 419 */ 420 hlmp = lml->lm_head; 421 if (FLAGS(hlmp) & FLG_RT_RELOCED) { 422 Lm_cntl *lmc; 423 424 if ((lmc = alist_append(&lml->lm_lists, 0, sizeof (Lm_cntl), 425 AL_CNT_LMLISTS)) == NULL) { 426 remove_plist(&palp, 1); 427 return (NULL); 428 } 429 lmco = (Aliste)((char *)lmc - (char *)lml->lm_lists); 430 } else 431 lmco = ALIST_OFF_DATA; 432 433 /* 434 * Load the associated object. 435 */ 436 dip->di_info = nlmp = 437 load_one(lml, lmco, palp, clmp, MODE(clmp), flags, 0, in_nfavl); 438 439 /* 440 * Remove any expanded pathname infrastructure. Reduce the pending lazy 441 * dependency count of the caller, together with the link-map lists 442 * count of objects that still have lazy dependencies pending. 443 */ 444 remove_plist(&palp, 1); 445 if (--LAZY(clmp) == 0) 446 LIST(clmp)->lm_lazy--; 447 448 /* 449 * Finish processing the objects associated with this request, and 450 * create an association between the caller and this dependency. 451 */ 452 if (nlmp && ((bind_one(clmp, nlmp, BND_NEEDED) == 0) || 453 ((nlmp = analyze_lmc(lml, lmco, nlmp, in_nfavl)) == NULL) || 454 (relocate_lmc(lml, lmco, clmp, nlmp, in_nfavl) == 0))) 455 dip->di_info = nlmp = NULL; 456 457 /* 458 * If this lazyload has failed, and we've created a new link-map 459 * control list to which this request has added objects, then remove 460 * all the objects that have been associated to this request. 461 */ 462 if ((nlmp == NULL) && (lmco != ALIST_OFF_DATA)) 463 remove_lmc(lml, clmp, lmco, name); 464 465 /* 466 * Finally, remove any link-map control list that was created. 467 */ 468 if (lmco != ALIST_OFF_DATA) 469 remove_cntl(lml, lmco); 470 471 /* 472 * If this lazy loading failed, record the fact, and bump the lazy 473 * counts. 474 */ 475 if (nlmp == NULL) { 476 dip->di_flags |= FLG_DI_LAZYFAIL; 477 if (LAZY(clmp)++ == 0) 478 LIST(clmp)->lm_lazy++; 479 } 480 481 return (nlmp); 482 } 483 484 /* 485 * Return the entry point of the ELF executable. 486 */ 487 static Addr 488 elf_entry_point(void) 489 { 490 Rt_map *lmp = lml_main.lm_head; 491 Ehdr *ehdr = (Ehdr *)ADDR(lmp); 492 Addr addr = (Addr)(ehdr->e_entry); 493 494 if ((FLAGS(lmp) & FLG_RT_FIXED) == 0) 495 addr += ADDR(lmp); 496 497 return (addr); 498 } 499 500 /* 501 * Determine if a dependency requires a particular version and if so verify 502 * that the version exists in the dependency. 503 */ 504 int 505 elf_verify_vers(const char *name, Rt_map *clmp, Rt_map *nlmp) 506 { 507 Verneed *vnd = VERNEED(clmp); 508 int _num, num = VERNEEDNUM(clmp); 509 char *cstrs = (char *)STRTAB(clmp); 510 Lm_list *lml = LIST(clmp); 511 512 /* 513 * Traverse the callers version needed information and determine if any 514 * specific versions are required from the dependency. 515 */ 516 DBG_CALL(Dbg_ver_need_title(LIST(clmp), NAME(clmp))); 517 for (_num = 1; _num <= num; _num++, 518 vnd = (Verneed *)((Xword)vnd + vnd->vn_next)) { 519 Half cnt = vnd->vn_cnt; 520 Vernaux *vnap; 521 char *nstrs, *need; 522 523 /* 524 * Determine if a needed entry matches this dependency. 525 */ 526 need = (char *)(cstrs + vnd->vn_file); 527 if (strcmp(name, need) != 0) 528 continue; 529 530 if ((lml->lm_flags & LML_FLG_TRC_VERBOSE) && 531 ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0)) 532 (void) printf(MSG_INTL(MSG_LDD_VER_FIND), name); 533 534 /* 535 * Validate that each version required actually exists in the 536 * dependency. 537 */ 538 nstrs = (char *)STRTAB(nlmp); 539 540 for (vnap = (Vernaux *)((Xword)vnd + vnd->vn_aux); cnt; 541 cnt--, vnap = (Vernaux *)((Xword)vnap + vnap->vna_next)) { 542 char *version, *define; 543 Verdef *vdf = VERDEF(nlmp); 544 ulong_t _num, num = VERDEFNUM(nlmp); 545 int found = 0; 546 547 /* 548 * Skip validation of versions that are marked 549 * INFO. This optimization is used for versions 550 * that are inherited by another version. Verification 551 * of the inheriting version is sufficient. 552 * 553 * Such versions are recorded in the object for the 554 * benefit of VERSYM entries that refer to them. This 555 * provides a purely diagnositic benefit. 556 */ 557 if (vnap->vna_flags & VER_FLG_INFO) 558 continue; 559 560 version = (char *)(cstrs + vnap->vna_name); 561 DBG_CALL(Dbg_ver_need_entry(lml, 0, need, version)); 562 563 for (_num = 1; _num <= num; _num++, 564 vdf = (Verdef *)((Xword)vdf + vdf->vd_next)) { 565 Verdaux *vdap; 566 567 if (vnap->vna_hash != vdf->vd_hash) 568 continue; 569 570 vdap = (Verdaux *)((Xword)vdf + vdf->vd_aux); 571 define = (char *)(nstrs + vdap->vda_name); 572 if (strcmp(version, define) != 0) 573 continue; 574 575 found++; 576 break; 577 } 578 579 /* 580 * If we're being traced print out any matched version 581 * when the verbose (-v) option is in effect. Always 582 * print any unmatched versions. 583 */ 584 if (lml->lm_flags & LML_FLG_TRC_ENABLE) { 585 /* BEGIN CSTYLED */ 586 if (found) { 587 if (!(lml->lm_flags & LML_FLG_TRC_VERBOSE)) 588 continue; 589 590 (void) printf(MSG_ORIG(MSG_LDD_VER_FOUND), 591 need, version, NAME(nlmp)); 592 } else { 593 if (rtld_flags & RT_FL_SILENCERR) 594 continue; 595 596 (void) printf(MSG_INTL(MSG_LDD_VER_NFOUND), 597 need, version); 598 } 599 /* END CSTYLED */ 600 continue; 601 } 602 603 /* 604 * If the version hasn't been found then this is a 605 * candidate for a fatal error condition. Weak 606 * version definition requirements are silently 607 * ignored. Also, if the image inspected for a version 608 * definition has no versioning recorded at all then 609 * silently ignore this (this provides better backward 610 * compatibility to old images created prior to 611 * versioning being available). Both of these skipped 612 * diagnostics are available under tracing (see above). 613 */ 614 if ((found == 0) && (num != 0) && 615 (!(vnap->vna_flags & VER_FLG_WEAK))) { 616 eprintf(lml, ERR_FATAL, 617 MSG_INTL(MSG_VER_NFOUND), need, version, 618 NAME(clmp)); 619 return (0); 620 } 621 } 622 } 623 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD)); 624 return (1); 625 } 626 627 /* 628 * Search through the dynamic section for DT_NEEDED entries and perform one 629 * of two functions. If only the first argument is specified then load the 630 * defined shared object, otherwise add the link map representing the defined 631 * link map the the dlopen list. 632 */ 633 static int 634 elf_needed(Lm_list *lml, Aliste lmco, Rt_map *clmp, int *in_nfavl) 635 { 636 Alist *palp = NULL; 637 Dyn *dyn, *pdyn; 638 ulong_t ndx = 0; 639 uint_t lazy, flags; 640 Word lmflags = lml->lm_flags; 641 Word lmtflags = lml->lm_tflags; 642 643 /* 644 * Process each shared object on needed list. 645 */ 646 if (DYN(clmp) == NULL) 647 return (1); 648 649 for (dyn = (Dyn *)DYN(clmp), pdyn = NULL; dyn->d_tag != DT_NULL; 650 pdyn = dyn++, ndx++) { 651 Dyninfo *dip = &DYNINFO(clmp)[ndx]; 652 Rt_map *nlmp = NULL; 653 char *name; 654 int silent = 0; 655 656 switch (dyn->d_tag) { 657 case DT_POSFLAG_1: 658 dip->di_flags |= FLG_DI_POSFLAG1; 659 continue; 660 case DT_NEEDED: 661 case DT_USED: 662 lazy = flags = 0; 663 dip->di_flags |= FLG_DI_NEEDED; 664 665 if (pdyn && (pdyn->d_tag == DT_POSFLAG_1)) { 666 if ((pdyn->d_un.d_val & DF_P1_LAZYLOAD) && 667 ((lmtflags & LML_TFLG_NOLAZYLD) == 0)) { 668 dip->di_flags |= FLG_DI_LAZY; 669 lazy = 1; 670 } 671 if (pdyn->d_un.d_val & DF_P1_GROUPPERM) { 672 dip->di_flags |= FLG_DI_GROUP; 673 flags = 674 (FLG_RT_SETGROUP | FLG_RT_HANDLE); 675 } 676 } 677 678 name = (char *)STRTAB(clmp) + dyn->d_un.d_val; 679 680 /* 681 * NOTE, libc.so.1 can't be lazy loaded. Although a 682 * lazy position flag won't be produced when a RTLDINFO 683 * .dynamic entry is found (introduced with the UPM in 684 * Solaris 10), it was possible to mark libc for lazy 685 * loading on previous releases. To reduce the overhead 686 * of testing for this occurrence, only carry out this 687 * check for the first object on the link-map list 688 * (there aren't many applications built without libc). 689 */ 690 if (lazy && (lml->lm_head == clmp) && 691 (strcmp(name, MSG_ORIG(MSG_FIL_LIBC)) == 0)) 692 lazy = 0; 693 694 /* 695 * Don't bring in lazy loaded objects yet unless we've 696 * been asked to attempt to load all available objects 697 * (crle(1) sets LD_FLAGS=loadavail). Even under 698 * RTLD_NOW we don't process this - RTLD_NOW will cause 699 * relocation processing which in turn might trigger 700 * lazy loading, but its possible that the object has a 701 * lazy loaded file with no bindings (i.e., it should 702 * never have been a dependency in the first place). 703 */ 704 if (lazy) { 705 if ((lmflags & LML_FLG_LOADAVAIL) == 0) { 706 LAZY(clmp)++; 707 lazy = flags = 0; 708 continue; 709 } 710 711 /* 712 * Silence any error messages - see description 713 * under elf_lookup_filtee(). 714 */ 715 if ((rtld_flags & RT_FL_SILENCERR) == 0) { 716 rtld_flags |= RT_FL_SILENCERR; 717 silent = 1; 718 } 719 } 720 break; 721 case DT_AUXILIARY: 722 dip->di_flags |= FLG_DI_AUXFLTR; 723 continue; 724 case DT_SUNW_AUXILIARY: 725 dip->di_flags |= (FLG_DI_AUXFLTR | FLG_DI_SYMFLTR); 726 continue; 727 case DT_FILTER: 728 dip->di_flags |= FLG_DI_STDFLTR; 729 continue; 730 case DT_SUNW_FILTER: 731 dip->di_flags |= (FLG_DI_STDFLTR | FLG_DI_SYMFLTR); 732 continue; 733 default: 734 continue; 735 } 736 737 DBG_CALL(Dbg_file_needed(clmp, name)); 738 739 /* 740 * If we're running under ldd(1), indicate that this dependency 741 * has been processed. It doesn't matter whether the object is 742 * successfully loaded or not, this flag simply ensures that we 743 * don't repeatedly attempt to load an object that has already 744 * failed to load. To do so would create multiple failure 745 * diagnostics for the same object under ldd(1). 746 */ 747 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 748 dip->di_flags |= FLG_DI_LDD_DONE; 749 750 /* 751 * Establish the objects name, load it and establish a binding 752 * with the caller. 753 */ 754 if ((elf_fix_name(name, clmp, &palp, AL_CNT_NEEDED, 0) == 0) || 755 ((nlmp = load_one(lml, lmco, palp, clmp, MODE(clmp), 756 flags, 0, in_nfavl)) == NULL) || 757 (bind_one(clmp, nlmp, BND_NEEDED) == 0)) 758 nlmp = NULL; 759 760 /* 761 * Clean up any infrastructure, including the removal of the 762 * error suppression state, if it had been previously set in 763 * this routine. 764 */ 765 remove_plist(&palp, 0); 766 767 if (silent) 768 rtld_flags &= ~RT_FL_SILENCERR; 769 770 if ((dip->di_info = (void *)nlmp) == NULL) { 771 /* 772 * If the object could not be mapped, continue if error 773 * suppression is established or we're here with ldd(1). 774 */ 775 if ((MODE(clmp) & RTLD_CONFGEN) || (lmflags & 776 (LML_FLG_LOADAVAIL | LML_FLG_TRC_ENABLE))) 777 continue; 778 else { 779 remove_plist(&palp, 1); 780 return (0); 781 } 782 } 783 } 784 785 if (LAZY(clmp)) 786 lml->lm_lazy++; 787 788 remove_plist(&palp, 1); 789 return (1); 790 } 791 792 /* 793 * A null symbol interpretor. Used if a filter has no associated filtees. 794 */ 795 /* ARGSUSED0 */ 796 static Sym * 797 elf_null_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo, int *in_nfavl) 798 { 799 return (NULL); 800 } 801 802 /* 803 * Disable filtee use. 804 */ 805 static void 806 elf_disable_filtee(Rt_map *lmp, Dyninfo *dip) 807 { 808 if ((dip->di_flags & FLG_DI_SYMFLTR) == 0) { 809 /* 810 * If this is an object filter, null out the reference name. 811 */ 812 if (OBJFLTRNDX(lmp) != FLTR_DISABLED) { 813 REFNAME(lmp) = NULL; 814 OBJFLTRNDX(lmp) = FLTR_DISABLED; 815 816 /* 817 * Indicate that this filtee is no longer available. 818 */ 819 if (dip->di_flags & FLG_DI_STDFLTR) 820 SYMINTP(lmp) = elf_null_find_sym; 821 822 } 823 } else if (dip->di_flags & FLG_DI_STDFLTR) { 824 /* 825 * Indicate that this standard filtee is no longer available. 826 */ 827 if (SYMSFLTRCNT(lmp)) 828 SYMSFLTRCNT(lmp)--; 829 } else { 830 /* 831 * Indicate that this auxiliary filtee is no longer available. 832 */ 833 if (SYMAFLTRCNT(lmp)) 834 SYMAFLTRCNT(lmp)--; 835 } 836 dip->di_flags &= ~MSK_DI_FILTER; 837 } 838 839 /* 840 * Find symbol interpreter - filters. 841 * This function is called when the symbols from a shared object should 842 * be resolved from the shared objects filtees instead of from within itself. 843 * 844 * A symbol name of 0 is used to trigger filtee loading. 845 */ 846 static Sym * 847 _elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx, 848 int *in_nfavl) 849 { 850 const char *name = slp->sl_name, *filtees; 851 Rt_map *clmp = slp->sl_cmap; 852 Rt_map *ilmp = slp->sl_imap; 853 Pdesc *pdp; 854 int any; 855 Dyninfo *dip = &DYNINFO(ilmp)[ndx]; 856 Lm_list *lml = LIST(ilmp); 857 Aliste idx; 858 859 /* 860 * Indicate that the filter has been used. If a binding already exists 861 * to the caller, indicate that this object is referenced. This insures 862 * we don't generate false unreferenced diagnostics from ldd -u/U or 863 * debugging. Don't create a binding regardless, as this filter may 864 * have been dlopen()'ed. 865 */ 866 if (name && (ilmp != clmp)) { 867 Word tracing = (LIST(clmp)->lm_flags & 868 (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED)); 869 870 if (tracing || DBG_ENABLED) { 871 Bnd_desc *bdp; 872 Aliste idx; 873 874 FLAGS1(ilmp) |= FL1_RT_USED; 875 876 if ((tracing & LML_FLG_TRC_UNREF) || DBG_ENABLED) { 877 for (APLIST_TRAVERSE(CALLERS(ilmp), idx, bdp)) { 878 if (bdp->b_caller == clmp) { 879 bdp->b_flags |= BND_REFER; 880 break; 881 } 882 } 883 } 884 } 885 } 886 887 /* 888 * If this is the first call to process this filter, establish the 889 * filtee list. If a configuration file exists, determine if any 890 * filtee associations for this filter, and its filtee reference, are 891 * defined. Otherwise, process the filtee reference. Any token 892 * expansion is also completed at this point (i.e., $PLATFORM). 893 */ 894 filtees = (char *)STRTAB(ilmp) + DYN(ilmp)[ndx].d_un.d_val; 895 if (dip->di_info == NULL) { 896 if (rtld_flags2 & RT_FL2_FLTCFG) 897 elf_config_flt(lml, PATHNAME(ilmp), filtees, 898 (Alist **)&dip->di_info, AL_CNT_FILTEES); 899 900 if (dip->di_info == NULL) { 901 DBG_CALL(Dbg_file_filter(lml, NAME(ilmp), filtees, 0)); 902 if ((lml->lm_flags & 903 (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_SEARCH)) && 904 ((FLAGS1(ilmp) & FL1_RT_LDDSTUB) == 0)) 905 (void) printf(MSG_INTL(MSG_LDD_FIL_FILTER), 906 NAME(ilmp), filtees); 907 908 if (expand_paths(ilmp, filtees, (Alist **)&dip->di_info, 909 AL_CNT_FILTEES, 0, 0) == 0) { 910 elf_disable_filtee(ilmp, dip); 911 return (NULL); 912 } 913 } 914 } 915 916 /* 917 * Traverse the filtee list, dlopen()'ing any objects specified and 918 * using their group handle to lookup the symbol. 919 */ 920 any = 0; 921 for (ALIST_TRAVERSE((Alist *)dip->di_info, idx, pdp)) { 922 int mode; 923 Grp_hdl *ghp; 924 Rt_map *nlmp = NULL; 925 926 if (pdp->pd_plen == 0) 927 continue; 928 929 /* 930 * Establish the mode of the filtee from the filter. As filtees 931 * are loaded via a dlopen(), make sure that RTLD_GROUP is set 932 * and the filtees aren't global. It would be nice to have 933 * RTLD_FIRST used here also, but as filters got out long before 934 * RTLD_FIRST was introduced it's a little too late now. 935 */ 936 mode = MODE(ilmp) | RTLD_GROUP; 937 mode &= ~RTLD_GLOBAL; 938 939 /* 940 * Insure that any auxiliary filter can locate symbols from its 941 * caller. 942 */ 943 if (dip->di_flags & FLG_DI_AUXFLTR) 944 mode |= RTLD_PARENT; 945 946 /* 947 * Process any hardware capability directory. Establish a new 948 * link-map control list from which to analyze any newly added 949 * objects. 950 */ 951 if ((pdp->pd_info == NULL) && (pdp->pd_flags & PD_TKN_HWCAP)) { 952 const char *dir = pdp->pd_pname; 953 Aliste lmco; 954 955 if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) { 956 Lm_cntl *lmc; 957 958 if ((lmc = alist_append(&lml->lm_lists, 0, 959 sizeof (Lm_cntl), AL_CNT_LMLISTS)) == NULL) 960 return (NULL); 961 lmco = (Aliste)((char *)lmc - 962 (char *)lml->lm_lists); 963 } else 964 lmco = ALIST_OFF_DATA; 965 966 /* 967 * Determine the hardware capability filtees. If none 968 * can be found, provide suitable diagnostics. 969 */ 970 DBG_CALL(Dbg_cap_hw_filter(lml, dir, ilmp)); 971 if (hwcap_filtees((Alist **)&dip->di_info, idx, dir, 972 lmco, ilmp, filtees, mode, 973 (FLG_RT_HANDLE | FLG_RT_HWCAP), in_nfavl) == 0) { 974 if ((lml->lm_flags & LML_FLG_TRC_ENABLE) && 975 (dip->di_flags & FLG_DI_AUXFLTR) && 976 (rtld_flags & RT_FL_WARNFLTR)) { 977 (void) printf( 978 MSG_INTL(MSG_LDD_HWCAP_NFOUND), 979 dir); 980 } 981 DBG_CALL(Dbg_cap_hw_filter(lml, dir, 0)); 982 } 983 984 /* 985 * Re-establish the originating path name descriptor, as 986 * the expansion of hardware capabilities filtees may 987 * have re-allocated the controlling Alist. Mark this 988 * original pathname descriptor as unused so that the 989 * descriptor isn't revisited for processing. Any real 990 * hardware capabilities filtees have been added as new 991 * pathname descriptors following this descriptor. 992 */ 993 pdp = alist_item((Alist *)dip->di_info, idx); 994 pdp->pd_flags &= ~PD_TKN_HWCAP; 995 pdp->pd_plen = 0; 996 997 /* 998 * Now that any hardware capability objects have been 999 * processed, remove any link-map control list. 1000 */ 1001 if (lmco != ALIST_OFF_DATA) 1002 remove_cntl(lml, lmco); 1003 } 1004 1005 if (pdp->pd_plen == 0) 1006 continue; 1007 1008 /* 1009 * Process an individual filtee. 1010 */ 1011 if (pdp->pd_info == NULL) { 1012 const char *filtee = pdp->pd_pname; 1013 int audit = 0; 1014 1015 DBG_CALL(Dbg_file_filtee(lml, NAME(ilmp), filtee, 0)); 1016 1017 ghp = NULL; 1018 1019 /* 1020 * Determine if the reference link map is already 1021 * loaded. As an optimization compare the filtee with 1022 * our interpretor. The most common filter is 1023 * libdl.so.1, which is a filter on ld.so.1. 1024 */ 1025 #if defined(_ELF64) 1026 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD_64)) == 0) { 1027 #else 1028 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD)) == 0) { 1029 #endif 1030 /* 1031 * Create an association between ld.so.1 and the 1032 * filter. As an optimization, a handle for 1033 * ld.so.1 itself (required for the dlopen() 1034 * family filtering mechanism) shouldn't search 1035 * any dependencies of ld.so.1. Omitting 1036 * GPD_ADDEPS prevents the addition of any 1037 * ld.so.1 dependencies to this handle. 1038 */ 1039 nlmp = lml_rtld.lm_head; 1040 if ((ghp = hdl_create(&lml_rtld, nlmp, ilmp, 1041 (GPH_LDSO | GPH_FIRST | GPH_FILTEE), 1042 (GPD_DLSYM | GPD_RELOC), GPD_PARENT)) == 1043 NULL) 1044 nlmp = NULL; 1045 1046 /* 1047 * Establish the filter handle to prevent any 1048 * recursion. 1049 */ 1050 if (nlmp && ghp) 1051 pdp->pd_info = (void *)ghp; 1052 1053 /* 1054 * Audit the filter/filtee established. Ignore 1055 * any return from the auditor, as we can't 1056 * allow ignore filtering to ld.so.1, otherwise 1057 * nothing is going to work. 1058 */ 1059 if (nlmp && ((lml->lm_tflags | AFLAGS(ilmp)) & 1060 LML_TFLG_AUD_OBJFILTER)) 1061 (void) audit_objfilter(ilmp, filtees, 1062 nlmp, 0); 1063 1064 } else { 1065 Rej_desc rej = { 0 }; 1066 Fdesc fd = { 0 }; 1067 Aliste lmco; 1068 1069 /* 1070 * Trace the inspection of this file, determine 1071 * any auditor substitution, and seed the file 1072 * descriptor with the originating name. 1073 */ 1074 if (load_trace(lml, pdp, clmp, &fd) == NULL) 1075 continue; 1076 1077 /* 1078 * Establish a new link-map control list from 1079 * which to analyze any newly added objects. 1080 */ 1081 if (FLAGS(lml->lm_head) & FLG_RT_RELOCED) { 1082 Lm_cntl *lmc; 1083 1084 if ((lmc = 1085 alist_append(&lml->lm_lists, 0, 1086 sizeof (Lm_cntl), 1087 AL_CNT_LMLISTS)) == NULL) 1088 return (NULL); 1089 lmco = (Aliste)((char *)lmc - 1090 (char *)lml->lm_lists); 1091 } else 1092 lmco = ALIST_OFF_DATA; 1093 1094 /* 1095 * Locate and load the filtee. 1096 */ 1097 if ((nlmp = load_path(lml, lmco, ilmp, mode, 1098 FLG_RT_HANDLE, &ghp, &fd, &rej, 1099 in_nfavl)) == NULL) 1100 file_notfound(LIST(ilmp), filtee, ilmp, 1101 FLG_RT_HANDLE, &rej); 1102 1103 filtee = pdp->pd_pname; 1104 1105 /* 1106 * Establish the filter handle to prevent any 1107 * recursion. 1108 */ 1109 if (nlmp && ghp) { 1110 ghp->gh_flags |= GPH_FILTEE; 1111 pdp->pd_info = (void *)ghp; 1112 1113 FLAGS1(nlmp) |= FL1_RT_USED; 1114 } 1115 1116 /* 1117 * Audit the filter/filtee established. A 1118 * return of 0 indicates the auditor wishes to 1119 * ignore this filtee. 1120 */ 1121 if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) & 1122 LML_TFLG_AUD_OBJFILTER)) { 1123 if (audit_objfilter(ilmp, filtees, 1124 nlmp, 0) == 0) { 1125 audit = 1; 1126 nlmp = NULL; 1127 } 1128 } 1129 1130 /* 1131 * Finish processing the objects associated with 1132 * this request. Create an association between 1133 * this object and the originating filter to 1134 * provide sufficient information to tear down 1135 * this filtee if necessary. 1136 */ 1137 if (nlmp && ghp && (((nlmp = analyze_lmc(lml, 1138 lmco, nlmp, in_nfavl)) == NULL) || 1139 (relocate_lmc(lml, lmco, ilmp, nlmp, 1140 in_nfavl) == 0))) 1141 nlmp = NULL; 1142 1143 /* 1144 * If the filtee has been successfully 1145 * processed, then create an association 1146 * between the filter and filtee. This 1147 * association provides sufficient information 1148 * to tear down the filter and filtee if 1149 * necessary. 1150 */ 1151 DBG_CALL(Dbg_file_hdl_title(DBG_HDL_ADD)); 1152 if (nlmp && ghp && 1153 (hdl_add(ghp, ilmp, GPD_FILTER) == 0)) 1154 nlmp = NULL; 1155 1156 /* 1157 * Generate a diagnostic if the filtee couldn't 1158 * be loaded. 1159 */ 1160 if (nlmp == NULL) 1161 DBG_CALL(Dbg_file_filtee(lml, 0, filtee, 1162 audit)); 1163 1164 /* 1165 * If this filtee loading has failed, and we've 1166 * created a new link-map control list to which 1167 * this request has added objects, then remove 1168 * all the objects that have been associated to 1169 * this request. 1170 */ 1171 if ((nlmp == NULL) && (lmco != ALIST_OFF_DATA)) 1172 remove_lmc(lml, clmp, lmco, name); 1173 1174 /* 1175 * Remove any link-map control list that was 1176 * created. 1177 */ 1178 if (lmco != ALIST_OFF_DATA) 1179 remove_cntl(lml, lmco); 1180 } 1181 1182 /* 1183 * If the filtee couldn't be loaded, null out the 1184 * path name descriptor entry, and continue the search. 1185 * Otherwise, the group handle is retained for future 1186 * symbol searches. 1187 */ 1188 if (nlmp == NULL) { 1189 pdp->pd_info = NULL; 1190 pdp->pd_plen = 0; 1191 continue; 1192 } 1193 } 1194 1195 ghp = (Grp_hdl *)pdp->pd_info; 1196 1197 /* 1198 * If we're just here to trigger filtee loading skip the symbol 1199 * lookup so we'll continue looking for additional filtees. 1200 */ 1201 if (name) { 1202 Grp_desc *gdp; 1203 Sym *sym = NULL; 1204 Aliste idx; 1205 Slookup sl = *slp; 1206 1207 sl.sl_flags |= LKUP_FIRST; 1208 any++; 1209 1210 /* 1211 * Look for the symbol in the handles dependencies. 1212 */ 1213 for (ALIST_TRAVERSE(ghp->gh_depends, idx, gdp)) { 1214 if ((gdp->gd_flags & GPD_DLSYM) == 0) 1215 continue; 1216 1217 /* 1218 * If our parent is a dependency don't look at 1219 * it (otherwise we are in a recursive loop). 1220 * This situation can occur with auxiliary 1221 * filters if the filtee has a dependency on the 1222 * filter. This dependency isn't necessary as 1223 * auxiliary filters are opened RTLD_PARENT, but 1224 * users may still unknowingly add an explicit 1225 * dependency to the parent. 1226 */ 1227 if ((sl.sl_imap = gdp->gd_depend) == ilmp) 1228 continue; 1229 1230 if (((sym = SYMINTP(sl.sl_imap)(&sl, dlmp, 1231 binfo, in_nfavl)) != NULL) || 1232 (ghp->gh_flags & GPH_FIRST)) 1233 break; 1234 } 1235 1236 /* 1237 * If a symbol has been found, indicate the binding 1238 * and return the symbol. 1239 */ 1240 if (sym) { 1241 *binfo |= DBG_BINFO_FILTEE; 1242 return (sym); 1243 } 1244 } 1245 1246 /* 1247 * If this object is tagged to terminate filtee processing we're 1248 * done. 1249 */ 1250 if (FLAGS1(ghp->gh_ownlmp) & FL1_RT_ENDFILTE) 1251 break; 1252 } 1253 1254 /* 1255 * If we're just here to trigger filtee loading then we're done. 1256 */ 1257 if (name == NULL) 1258 return (NULL); 1259 1260 /* 1261 * If no filtees have been found for a filter, clean up any path name 1262 * descriptors and disable their search completely. For auxiliary 1263 * filters we can reselect the symbol search function so that we never 1264 * enter this routine again for this object. For standard filters we 1265 * use the null symbol routine. 1266 */ 1267 if (any == 0) { 1268 remove_plist((Alist **)&(dip->di_info), 1); 1269 elf_disable_filtee(ilmp, dip); 1270 return (NULL); 1271 } 1272 1273 return (NULL); 1274 } 1275 1276 /* 1277 * Focal point for disabling error messages for auxiliary filters. As an 1278 * auxiliary filter allows for filtee use, but provides a fallback should a 1279 * filtee not exist (or fail to load), any errors generated as a consequence of 1280 * trying to load the filtees are typically suppressed. Setting RT_FL_SILENCERR 1281 * suppresses errors generated by eprint(), but insures a debug diagnostic is 1282 * produced. ldd(1) employs printf(), and here, the selection of whether to 1283 * print a diagnostic in regards to auxiliary filters is a little more complex. 1284 * 1285 * . The determination of whether to produce an ldd message, or a fatal 1286 * error message is driven by LML_FLG_TRC_ENABLE. 1287 * . More detailed ldd messages may also be driven off of LML_FLG_TRC_WARN, 1288 * (ldd -d/-r), LML_FLG_TRC_VERBOSE (ldd -v), LML_FLG_TRC_SEARCH (ldd -s), 1289 * and LML_FLG_TRC_UNREF/LML_FLG_TRC_UNUSED (ldd -U/-u). 1290 * 1291 * . If the calling object is lddstub, then several classes of message are 1292 * suppressed. The user isn't trying to diagnose lddstub, this is simply 1293 * a stub executable employed to preload a user specified library against. 1294 * 1295 * . If RT_FL_SILENCERR is in effect then any generic ldd() messages should 1296 * be suppressed. All detailed ldd messages should still be produced. 1297 */ 1298 Sym * 1299 elf_lookup_filtee(Slookup *slp, Rt_map **dlmp, uint_t *binfo, uint_t ndx, 1300 int *in_nfavl) 1301 { 1302 Sym *sym; 1303 Dyninfo *dip = &DYNINFO(slp->sl_imap)[ndx]; 1304 int silent = 0; 1305 1306 /* 1307 * Make sure this entry is still acting as a filter. We may have tried 1308 * to process this previously, and disabled it if the filtee couldn't 1309 * be processed. However, other entries may provide different filtees 1310 * that are yet to be completed. 1311 */ 1312 if (dip->di_flags == 0) 1313 return (NULL); 1314 1315 /* 1316 * Indicate whether an error message is required should this filtee not 1317 * be found, based on the type of filter. 1318 */ 1319 if ((dip->di_flags & FLG_DI_AUXFLTR) && 1320 ((rtld_flags & (RT_FL_WARNFLTR | RT_FL_SILENCERR)) == 0)) { 1321 rtld_flags |= RT_FL_SILENCERR; 1322 silent = 1; 1323 } 1324 1325 sym = _elf_lookup_filtee(slp, dlmp, binfo, ndx, in_nfavl); 1326 1327 if (silent) 1328 rtld_flags &= ~RT_FL_SILENCERR; 1329 1330 return (sym); 1331 } 1332 1333 /* 1334 * Compute the elf hash value (as defined in the ELF access library). 1335 * The form of the hash table is: 1336 * 1337 * |--------------| 1338 * | # of buckets | 1339 * |--------------| 1340 * | # of chains | 1341 * |--------------| 1342 * | bucket[] | 1343 * |--------------| 1344 * | chain[] | 1345 * |--------------| 1346 */ 1347 ulong_t 1348 elf_hash(const char *name) 1349 { 1350 uint_t hval = 0; 1351 1352 while (*name) { 1353 uint_t g; 1354 hval = (hval << 4) + *name++; 1355 if ((g = (hval & 0xf0000000)) != 0) 1356 hval ^= g >> 24; 1357 hval &= ~g; 1358 } 1359 return ((ulong_t)hval); 1360 } 1361 1362 /* 1363 * If flag argument has LKUP_SPEC set, we treat undefined symbols of type 1364 * function specially in the executable - if they have a value, even though 1365 * undefined, we use that value. This allows us to associate all references 1366 * to a function's address to a single place in the process: the plt entry 1367 * for that function in the executable. Calls to lookup from plt binding 1368 * routines do NOT set LKUP_SPEC in the flag. 1369 */ 1370 Sym * 1371 elf_find_sym(Slookup *slp, Rt_map **dlmp, uint_t *binfo, int *in_nfavl) 1372 { 1373 const char *name = slp->sl_name; 1374 Rt_map *ilmp = slp->sl_imap; 1375 ulong_t hash = slp->sl_hash; 1376 uint_t ndx, htmp, buckets, *chainptr; 1377 Sym *sym, *symtabptr; 1378 char *strtabptr, *strtabname; 1379 uint_t flags1; 1380 Syminfo *sip; 1381 1382 /* 1383 * If we're only here to establish a symbols index, skip the diagnostic 1384 * used to trace a symbol search. 1385 */ 1386 if ((slp->sl_flags & LKUP_SYMNDX) == 0) 1387 DBG_CALL(Dbg_syms_lookup(ilmp, name, MSG_ORIG(MSG_STR_ELF))); 1388 1389 if (HASH(ilmp) == NULL) 1390 return (NULL); 1391 1392 buckets = HASH(ilmp)[0]; 1393 /* LINTED */ 1394 htmp = (uint_t)hash % buckets; 1395 1396 /* 1397 * Get the first symbol on hash chain and initialize the string 1398 * and symbol table pointers. 1399 */ 1400 if ((ndx = HASH(ilmp)[htmp + 2]) == 0) 1401 return (NULL); 1402 1403 chainptr = HASH(ilmp) + 2 + buckets; 1404 strtabptr = STRTAB(ilmp); 1405 symtabptr = SYMTAB(ilmp); 1406 1407 while (ndx) { 1408 sym = symtabptr + ndx; 1409 strtabname = strtabptr + sym->st_name; 1410 1411 /* 1412 * Compare the symbol found with the name required. If the 1413 * names don't match continue with the next hash entry. 1414 */ 1415 if ((*strtabname++ != *name) || strcmp(strtabname, &name[1])) { 1416 if ((ndx = chainptr[ndx]) != 0) 1417 continue; 1418 return (NULL); 1419 } 1420 1421 /* 1422 * The Solaris ld does not put DT_VERSYM in the dynamic 1423 * section, but the GNU ld does. The GNU runtime linker 1424 * interprets the top bit of the 16-bit Versym value 1425 * (0x8000) as the "hidden" bit. If this bit is set, 1426 * the linker is supposed to act as if that symbol does 1427 * not exist. The hidden bit supports their versioning 1428 * scheme, which allows multiple incompatible functions 1429 * with the same name to exist at different versions 1430 * within an object. The Solaris linker does not support this 1431 * mechanism, or the model of interface evolution that 1432 * it allows, but we honor the hidden bit in GNU ld 1433 * produced objects in order to interoperate with them. 1434 */ 1435 if ((VERSYM(ilmp) != NULL) && 1436 ((VERSYM(ilmp)[ndx] & 0x8000) != 0)) { 1437 DBG_CALL(Dbg_syms_ignore_gnuver(ilmp, name, 1438 ndx, VERSYM(ilmp)[ndx])); 1439 if ((ndx = chainptr[ndx]) != 0) 1440 continue; 1441 return (NULL); 1442 } 1443 1444 /* 1445 * If we're only here to establish a symbols index, we're done. 1446 */ 1447 if (slp->sl_flags & LKUP_SYMNDX) 1448 return (sym); 1449 1450 /* 1451 * If we find a match and the symbol is defined, return the 1452 * symbol pointer and the link map in which it was found. 1453 */ 1454 if (sym->st_shndx != SHN_UNDEF) { 1455 *dlmp = ilmp; 1456 *binfo |= DBG_BINFO_FOUND; 1457 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) || 1458 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) && 1459 is_sym_interposer(ilmp, sym))) 1460 *binfo |= DBG_BINFO_INTERPOSE; 1461 break; 1462 1463 /* 1464 * If we find a match and the symbol is undefined, the 1465 * symbol type is a function, and the value of the symbol 1466 * is non zero, then this is a special case. This allows 1467 * the resolution of a function address to the plt[] entry. 1468 * See SPARC ABI, Dynamic Linking, Function Addresses for 1469 * more details. 1470 */ 1471 } else if ((slp->sl_flags & LKUP_SPEC) && 1472 (FLAGS(ilmp) & FLG_RT_ISMAIN) && (sym->st_value != 0) && 1473 (ELF_ST_TYPE(sym->st_info) == STT_FUNC)) { 1474 *dlmp = ilmp; 1475 *binfo |= (DBG_BINFO_FOUND | DBG_BINFO_PLTADDR); 1476 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) || 1477 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) && 1478 is_sym_interposer(ilmp, sym))) 1479 *binfo |= DBG_BINFO_INTERPOSE; 1480 return (sym); 1481 } 1482 1483 /* 1484 * Undefined symbol. 1485 */ 1486 return (NULL); 1487 } 1488 1489 /* 1490 * We've found a match. Determine if the defining object contains 1491 * symbol binding information. 1492 */ 1493 if ((sip = SYMINFO(ilmp)) != NULL) 1494 sip += ndx; 1495 1496 /* 1497 * If this definition is a singleton, and we haven't followed a default 1498 * symbol search knowing that we're looking for a singleton (presumably 1499 * because the symbol definition has been changed since the referring 1500 * object was built), then reject this binding so that the caller can 1501 * fall back to a standard symbol search. 1502 */ 1503 if ((ELF_ST_VISIBILITY(sym->st_other) == STV_SINGLETON) && 1504 (((slp->sl_flags & LKUP_STANDARD) == 0) || 1505 (((slp->sl_flags & LKUP_SINGLETON) == 0) && 1506 (LIST(ilmp)->lm_flags & LML_FLG_GROUPSEXIST)))) { 1507 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name, 1508 DBG_BNDREJ_SINGLE)); 1509 *binfo |= BINFO_REJSINGLE; 1510 *binfo &= ~DBG_BINFO_MSK; 1511 return (NULL); 1512 } 1513 1514 /* 1515 * If this is a direct binding request, but the symbol definition has 1516 * disabled directly binding to it (presumably because the symbol 1517 * definition has been changed since the referring object was built), 1518 * reject this binding so that the caller can fall back to a standard 1519 * symbol search. 1520 */ 1521 if (sip && (slp->sl_flags & LKUP_DIRECT) && 1522 (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT)) { 1523 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name, 1524 DBG_BNDREJ_DIRECT)); 1525 *binfo |= BINFO_REJDIRECT; 1526 *binfo &= ~DBG_BINFO_MSK; 1527 return (NULL); 1528 } 1529 1530 /* 1531 * If this is a binding request within an RTLD_GROUP family, and the 1532 * symbol has disabled directly binding to it, reject this binding so 1533 * that the caller can fall back to a standard symbol search. 1534 * 1535 * Effectively, an RTLD_GROUP family achieves what can now be 1536 * established with direct bindings. However, various symbols have 1537 * been tagged as inappropriate for direct binding to (ie. libc:malloc). 1538 * 1539 * A symbol marked as no-direct cannot be used within a group without 1540 * first ensuring that the symbol has not been interposed upon outside 1541 * of the group. A common example occurs when users implement their own 1542 * version of malloc() in the executable. Such a malloc() interposes on 1543 * the libc:malloc, and this interposition must be honored within the 1544 * group as well. 1545 * 1546 * Following any rejection, LKUP_WORLD is established as a means of 1547 * overriding this test as we return to a standard search. 1548 */ 1549 if (sip && (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT) && 1550 ((MODE(slp->sl_cmap) & (RTLD_GROUP | RTLD_WORLD)) == RTLD_GROUP) && 1551 ((slp->sl_flags & LKUP_WORLD) == 0)) { 1552 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name, 1553 DBG_BNDREJ_GROUP)); 1554 *binfo |= BINFO_REJGROUP; 1555 *binfo &= ~DBG_BINFO_MSK; 1556 return (NULL); 1557 } 1558 1559 /* 1560 * Determine whether this object is acting as a filter. 1561 */ 1562 if (((flags1 = FLAGS1(ilmp)) & MSK_RT_FILTER) == 0) 1563 return (sym); 1564 1565 /* 1566 * Determine if this object offers per-symbol filtering, and if so, 1567 * whether this symbol references a filtee. 1568 */ 1569 if (sip && (flags1 & (FL1_RT_SYMSFLTR | FL1_RT_SYMAFLTR))) { 1570 /* 1571 * If this is a standard filter reference, and no standard 1572 * filtees remain to be inspected, we're done. If this is an 1573 * auxiliary filter reference, and no auxiliary filtees remain, 1574 * we'll fall through in case any object filtering is available. 1575 */ 1576 if ((sip->si_flags & SYMINFO_FLG_FILTER) && 1577 (SYMSFLTRCNT(ilmp) == 0)) 1578 return (NULL); 1579 1580 if ((sip->si_flags & SYMINFO_FLG_FILTER) || 1581 ((sip->si_flags & SYMINFO_FLG_AUXILIARY) && 1582 SYMAFLTRCNT(ilmp))) { 1583 Sym *fsym; 1584 1585 /* 1586 * This symbol has an associated filtee. Lookup the 1587 * symbol in the filtee, and if it is found return it. 1588 * If the symbol doesn't exist, and this is a standard 1589 * filter, return an error, otherwise fall through to 1590 * catch any object filtering that may be available. 1591 */ 1592 if ((fsym = elf_lookup_filtee(slp, dlmp, binfo, 1593 sip->si_boundto, in_nfavl)) != NULL) 1594 return (fsym); 1595 if (sip->si_flags & SYMINFO_FLG_FILTER) 1596 return (NULL); 1597 } 1598 } 1599 1600 /* 1601 * Determine if this object provides global filtering. 1602 */ 1603 if (flags1 & (FL1_RT_OBJSFLTR | FL1_RT_OBJAFLTR)) { 1604 Sym *fsym; 1605 1606 if (OBJFLTRNDX(ilmp) != FLTR_DISABLED) { 1607 /* 1608 * This object has an associated filtee. Lookup the 1609 * symbol in the filtee, and if it is found return it. 1610 * If the symbol doesn't exist, and this is a standard 1611 * filter, return and error, otherwise return the symbol 1612 * within the filter itself. 1613 */ 1614 if ((fsym = elf_lookup_filtee(slp, dlmp, binfo, 1615 OBJFLTRNDX(ilmp), in_nfavl)) != NULL) 1616 return (fsym); 1617 } 1618 1619 if (flags1 & FL1_RT_OBJSFLTR) 1620 return (NULL); 1621 } 1622 return (sym); 1623 } 1624 1625 /* 1626 * Create a new Rt_map structure for an ELF object and initialize 1627 * all values. 1628 */ 1629 Rt_map * 1630 elf_new_lmp(Lm_list *lml, Aliste lmco, Fdesc *fdp, Addr addr, size_t msize, 1631 void *odyn, int *in_nfavl) 1632 { 1633 const char *name = fdp->fd_nname; 1634 Rt_map *lmp; 1635 Ehdr *ehdr = (Ehdr *)addr; 1636 Phdr *phdr, *tphdr = NULL, *dphdr = NULL, *uphdr = NULL; 1637 Dyn *dyn = (Dyn *)odyn; 1638 Cap *cap = NULL; 1639 int ndx; 1640 Addr base, fltr = 0, audit = 0, cfile = 0, crle = 0; 1641 Xword rpath = 0; 1642 size_t lmsz, rtsz, epsz, dynsz = 0; 1643 uint_t dyncnt = 0; 1644 1645 DBG_CALL(Dbg_file_elf(lml, name, addr, msize, lml->lm_lmidstr, lmco)); 1646 1647 /* 1648 * If this is a shared object, the base address of the shared object is 1649 * added to all address values defined within the object. Otherwise, if 1650 * this is an executable, all object addresses are used as is. 1651 */ 1652 if (ehdr->e_type == ET_EXEC) 1653 base = 0; 1654 else 1655 base = addr; 1656 1657 /* 1658 * Traverse the program header table, picking off required items. This 1659 * traversal also provides for the sizing of the PT_DYNAMIC section. 1660 */ 1661 phdr = (Phdr *)((uintptr_t)ehdr + ehdr->e_phoff); 1662 for (ndx = 0; ndx < (int)ehdr->e_phnum; ndx++, 1663 phdr = (Phdr *)((uintptr_t)phdr + ehdr->e_phentsize)) { 1664 switch (phdr->p_type) { 1665 case PT_DYNAMIC: 1666 dphdr = phdr; 1667 dyn = (Dyn *)((uintptr_t)phdr->p_vaddr + base); 1668 break; 1669 case PT_TLS: 1670 tphdr = phdr; 1671 break; 1672 case PT_SUNWCAP: 1673 cap = (Cap *)((uintptr_t)phdr->p_vaddr + base); 1674 break; 1675 case PT_SUNW_UNWIND: 1676 case PT_SUNW_EH_FRAME: 1677 uphdr = phdr; 1678 break; 1679 default: 1680 break; 1681 } 1682 } 1683 1684 /* 1685 * Determine the number of PT_DYNAMIC entries for the DYNINFO() 1686 * allocation. Sadly, this is a little larger than we really need, 1687 * as there are typically padding DT_NULL entries. However, adding 1688 * this data to the initial link-map allocation is a win. 1689 */ 1690 if (dyn) { 1691 dyncnt = dphdr->p_filesz / sizeof (Dyn); 1692 dynsz = dyncnt * sizeof (Dyninfo); 1693 } 1694 1695 /* 1696 * Allocate space for the link-map, private elf information, and 1697 * DYNINFO() data. Once these are allocated and initialized, 1698 * remove_so(0, lmp) can be used to tear down the link-map allocation 1699 * should any failures occur. 1700 */ 1701 rtsz = S_DROUND(sizeof (Rt_map)); 1702 epsz = S_DROUND(sizeof (Rt_elfp)); 1703 lmsz = rtsz + epsz + dynsz; 1704 if ((lmp = calloc(lmsz, 1)) == NULL) 1705 return (NULL); 1706 ELFPRV(lmp) = (void *)((uintptr_t)lmp + rtsz); 1707 DYNINFO(lmp) = (Dyninfo *)((uintptr_t)lmp + rtsz + epsz); 1708 LMSIZE(lmp) = lmsz; 1709 1710 /* 1711 * All fields not filled in were set to 0 by calloc. 1712 */ 1713 NAME(lmp) = (char *)name; 1714 ADDR(lmp) = addr; 1715 MSIZE(lmp) = msize; 1716 SYMINTP(lmp) = elf_find_sym; 1717 FCT(lmp) = &elf_fct; 1718 LIST(lmp) = lml; 1719 OBJFLTRNDX(lmp) = FLTR_DISABLED; 1720 SORTVAL(lmp) = -1; 1721 DYN(lmp) = dyn; 1722 DYNINFOCNT(lmp) = dyncnt; 1723 PTUNWIND(lmp) = uphdr; 1724 1725 if (ehdr->e_type == ET_EXEC) 1726 FLAGS(lmp) |= FLG_RT_FIXED; 1727 1728 /* 1729 * Fill in rest of the link map entries with information from the file's 1730 * dynamic structure. 1731 */ 1732 if (dyn) { 1733 uint_t dynndx = 0; 1734 Xword pltpadsz = 0; 1735 Rti_desc *rti; 1736 1737 /* CSTYLED */ 1738 for ( ; dyn->d_tag != DT_NULL; ++dyn, dynndx++) { 1739 switch ((Xword)dyn->d_tag) { 1740 case DT_SYMTAB: 1741 SYMTAB(lmp) = (void *)(dyn->d_un.d_ptr + base); 1742 break; 1743 case DT_SUNW_SYMTAB: 1744 SUNWSYMTAB(lmp) = 1745 (void *)(dyn->d_un.d_ptr + base); 1746 break; 1747 case DT_SUNW_SYMSZ: 1748 SUNWSYMSZ(lmp) = dyn->d_un.d_val; 1749 break; 1750 case DT_STRTAB: 1751 STRTAB(lmp) = (void *)(dyn->d_un.d_ptr + base); 1752 break; 1753 case DT_SYMENT: 1754 SYMENT(lmp) = dyn->d_un.d_val; 1755 break; 1756 case DT_FEATURE_1: 1757 dyn->d_un.d_val |= DTF_1_PARINIT; 1758 if (dyn->d_un.d_val & DTF_1_CONFEXP) 1759 crle = 1; 1760 break; 1761 case DT_MOVESZ: 1762 MOVESZ(lmp) = dyn->d_un.d_val; 1763 FLAGS(lmp) |= FLG_RT_MOVE; 1764 break; 1765 case DT_MOVEENT: 1766 MOVEENT(lmp) = dyn->d_un.d_val; 1767 break; 1768 case DT_MOVETAB: 1769 MOVETAB(lmp) = (void *)(dyn->d_un.d_ptr + base); 1770 break; 1771 case DT_REL: 1772 case DT_RELA: 1773 /* 1774 * At this time, ld.so. can only handle one 1775 * type of relocation per object. 1776 */ 1777 REL(lmp) = (void *)(dyn->d_un.d_ptr + base); 1778 break; 1779 case DT_RELSZ: 1780 case DT_RELASZ: 1781 RELSZ(lmp) = dyn->d_un.d_val; 1782 break; 1783 case DT_RELENT: 1784 case DT_RELAENT: 1785 RELENT(lmp) = dyn->d_un.d_val; 1786 break; 1787 case DT_RELCOUNT: 1788 case DT_RELACOUNT: 1789 RELACOUNT(lmp) = (uint_t)dyn->d_un.d_val; 1790 break; 1791 case DT_HASH: 1792 HASH(lmp) = (uint_t *)(dyn->d_un.d_ptr + base); 1793 break; 1794 case DT_PLTGOT: 1795 PLTGOT(lmp) = 1796 (uint_t *)(dyn->d_un.d_ptr + base); 1797 break; 1798 case DT_PLTRELSZ: 1799 PLTRELSZ(lmp) = dyn->d_un.d_val; 1800 break; 1801 case DT_JMPREL: 1802 JMPREL(lmp) = (void *)(dyn->d_un.d_ptr + base); 1803 break; 1804 case DT_INIT: 1805 if (dyn->d_un.d_ptr != NULL) 1806 INIT(lmp) = 1807 (void (*)())(dyn->d_un.d_ptr + 1808 base); 1809 break; 1810 case DT_FINI: 1811 if (dyn->d_un.d_ptr != NULL) 1812 FINI(lmp) = 1813 (void (*)())(dyn->d_un.d_ptr + 1814 base); 1815 break; 1816 case DT_INIT_ARRAY: 1817 INITARRAY(lmp) = (Addr *)(dyn->d_un.d_ptr + 1818 base); 1819 break; 1820 case DT_INIT_ARRAYSZ: 1821 INITARRAYSZ(lmp) = (uint_t)dyn->d_un.d_val; 1822 break; 1823 case DT_FINI_ARRAY: 1824 FINIARRAY(lmp) = (Addr *)(dyn->d_un.d_ptr + 1825 base); 1826 break; 1827 case DT_FINI_ARRAYSZ: 1828 FINIARRAYSZ(lmp) = (uint_t)dyn->d_un.d_val; 1829 break; 1830 case DT_PREINIT_ARRAY: 1831 PREINITARRAY(lmp) = (Addr *)(dyn->d_un.d_ptr + 1832 base); 1833 break; 1834 case DT_PREINIT_ARRAYSZ: 1835 PREINITARRAYSZ(lmp) = (uint_t)dyn->d_un.d_val; 1836 break; 1837 case DT_RPATH: 1838 case DT_RUNPATH: 1839 rpath = dyn->d_un.d_val; 1840 break; 1841 case DT_FILTER: 1842 fltr = dyn->d_un.d_val; 1843 OBJFLTRNDX(lmp) = dynndx; 1844 FLAGS1(lmp) |= FL1_RT_OBJSFLTR; 1845 break; 1846 case DT_AUXILIARY: 1847 if (!(rtld_flags & RT_FL_NOAUXFLTR)) { 1848 fltr = dyn->d_un.d_val; 1849 OBJFLTRNDX(lmp) = dynndx; 1850 } 1851 FLAGS1(lmp) |= FL1_RT_OBJAFLTR; 1852 break; 1853 case DT_SUNW_FILTER: 1854 SYMSFLTRCNT(lmp)++; 1855 FLAGS1(lmp) |= FL1_RT_SYMSFLTR; 1856 break; 1857 case DT_SUNW_AUXILIARY: 1858 if (!(rtld_flags & RT_FL_NOAUXFLTR)) { 1859 SYMAFLTRCNT(lmp)++; 1860 } 1861 FLAGS1(lmp) |= FL1_RT_SYMAFLTR; 1862 break; 1863 case DT_DEPAUDIT: 1864 if (!(rtld_flags & RT_FL_NOAUDIT)) 1865 audit = dyn->d_un.d_val; 1866 break; 1867 case DT_CONFIG: 1868 cfile = dyn->d_un.d_val; 1869 break; 1870 case DT_DEBUG: 1871 /* 1872 * DT_DEBUG entries are only created in 1873 * dynamic objects that require an interpretor 1874 * (ie. all dynamic executables and some shared 1875 * objects), and provide for a hand-shake with 1876 * debuggers. This entry is initialized to 1877 * zero by the link-editor. If a debugger has 1878 * us and updated this entry set the debugger 1879 * flag, and finish initializing the debugging 1880 * structure (see setup() also). Switch off any 1881 * configuration object use as most debuggers 1882 * can't handle fixed dynamic executables as 1883 * dependencies, and we can't handle requests 1884 * like object padding for alternative objects. 1885 */ 1886 if (dyn->d_un.d_ptr) 1887 rtld_flags |= 1888 (RT_FL_DEBUGGER | RT_FL_NOOBJALT); 1889 dyn->d_un.d_ptr = (Addr)&r_debug; 1890 break; 1891 case DT_VERNEED: 1892 VERNEED(lmp) = (Verneed *)(dyn->d_un.d_ptr + 1893 base); 1894 break; 1895 case DT_VERNEEDNUM: 1896 /* LINTED */ 1897 VERNEEDNUM(lmp) = (int)dyn->d_un.d_val; 1898 break; 1899 case DT_VERDEF: 1900 VERDEF(lmp) = (Verdef *)(dyn->d_un.d_ptr + 1901 base); 1902 break; 1903 case DT_VERDEFNUM: 1904 /* LINTED */ 1905 VERDEFNUM(lmp) = (int)dyn->d_un.d_val; 1906 break; 1907 case DT_VERSYM: 1908 /* 1909 * The Solaris ld does not produce DT_VERSYM, 1910 * but the GNU ld does, in order to support 1911 * their style of versioning, which differs 1912 * from ours in some ways, while using the 1913 * same data structures. The presence of 1914 * DT_VERSYM therefore means that GNU 1915 * versioning rules apply to the given file. 1916 * If DT_VERSYM is not present, then Solaris 1917 * versioning rules apply. 1918 */ 1919 VERSYM(lmp) = (Versym *)(dyn->d_un.d_ptr + 1920 base); 1921 break; 1922 case DT_BIND_NOW: 1923 if ((dyn->d_un.d_val & DF_BIND_NOW) && 1924 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 1925 MODE(lmp) |= RTLD_NOW; 1926 MODE(lmp) &= ~RTLD_LAZY; 1927 } 1928 break; 1929 case DT_FLAGS: 1930 FLAGS1(lmp) |= FL1_RT_DTFLAGS; 1931 if (dyn->d_un.d_val & DF_SYMBOLIC) 1932 FLAGS1(lmp) |= FL1_RT_SYMBOLIC; 1933 if ((dyn->d_un.d_val & DF_BIND_NOW) && 1934 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 1935 MODE(lmp) |= RTLD_NOW; 1936 MODE(lmp) &= ~RTLD_LAZY; 1937 } 1938 /* 1939 * Capture any static TLS use, and enforce that 1940 * this object be non-deletable. 1941 */ 1942 if (dyn->d_un.d_val & DF_STATIC_TLS) { 1943 FLAGS1(lmp) |= FL1_RT_TLSSTAT; 1944 MODE(lmp) |= RTLD_NODELETE; 1945 } 1946 break; 1947 case DT_FLAGS_1: 1948 if (dyn->d_un.d_val & DF_1_DISPRELPND) 1949 FLAGS1(lmp) |= FL1_RT_DISPREL; 1950 if (dyn->d_un.d_val & DF_1_GROUP) 1951 FLAGS(lmp) |= 1952 (FLG_RT_SETGROUP | FLG_RT_HANDLE); 1953 if ((dyn->d_un.d_val & DF_1_NOW) && 1954 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) { 1955 MODE(lmp) |= RTLD_NOW; 1956 MODE(lmp) &= ~RTLD_LAZY; 1957 } 1958 if (dyn->d_un.d_val & DF_1_NODELETE) 1959 MODE(lmp) |= RTLD_NODELETE; 1960 if (dyn->d_un.d_val & DF_1_INITFIRST) 1961 FLAGS(lmp) |= FLG_RT_INITFRST; 1962 if (dyn->d_un.d_val & DF_1_NOOPEN) 1963 FLAGS(lmp) |= FLG_RT_NOOPEN; 1964 if (dyn->d_un.d_val & DF_1_LOADFLTR) 1965 FLAGS(lmp) |= FLG_RT_LOADFLTR; 1966 if (dyn->d_un.d_val & DF_1_NODUMP) 1967 FLAGS(lmp) |= FLG_RT_NODUMP; 1968 if (dyn->d_un.d_val & DF_1_CONFALT) 1969 crle = 1; 1970 if (dyn->d_un.d_val & DF_1_DIRECT) 1971 FLAGS1(lmp) |= FL1_RT_DIRECT; 1972 if (dyn->d_un.d_val & DF_1_NODEFLIB) 1973 FLAGS1(lmp) |= FL1_RT_NODEFLIB; 1974 if (dyn->d_un.d_val & DF_1_ENDFILTEE) 1975 FLAGS1(lmp) |= FL1_RT_ENDFILTE; 1976 if (dyn->d_un.d_val & DF_1_TRANS) 1977 FLAGS(lmp) |= FLG_RT_TRANS; 1978 1979 /* 1980 * Global auditing is only meaningful when 1981 * specified by the initiating object of the 1982 * process - typically the dynamic executable. 1983 * If this is the initiaiting object, its link- 1984 * map will not yet have been added to the 1985 * link-map list, and consequently the link-map 1986 * list is empty. (see setup()). 1987 */ 1988 if (dyn->d_un.d_val & DF_1_GLOBAUDIT) { 1989 if (lml_main.lm_head == NULL) 1990 FLAGS1(lmp) |= FL1_RT_GLOBAUD; 1991 else 1992 DBG_CALL(Dbg_audit_ignore(lmp)); 1993 } 1994 1995 /* 1996 * If this object identifies itself as an 1997 * interposer, but relocation processing has 1998 * already started, then demote it. It's too 1999 * late to guarantee complete interposition. 2000 */ 2001 /* BEGIN CSTYLED */ 2002 if (dyn->d_un.d_val & 2003 (DF_1_INTERPOSE | DF_1_SYMINTPOSE)) { 2004 if (lml->lm_flags & LML_FLG_STARTREL) { 2005 DBG_CALL(Dbg_util_intoolate(lmp)); 2006 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 2007 (void) printf( 2008 MSG_INTL(MSG_LDD_REL_ERR2), 2009 NAME(lmp)); 2010 } else if (dyn->d_un.d_val & DF_1_INTERPOSE) 2011 FLAGS(lmp) |= FLG_RT_OBJINTPO; 2012 else 2013 FLAGS(lmp) |= FLG_RT_SYMINTPO; 2014 } 2015 /* END CSTYLED */ 2016 break; 2017 case DT_SYMINFO: 2018 SYMINFO(lmp) = (Syminfo *)(dyn->d_un.d_ptr + 2019 base); 2020 break; 2021 case DT_SYMINENT: 2022 SYMINENT(lmp) = dyn->d_un.d_val; 2023 break; 2024 case DT_PLTPAD: 2025 PLTPAD(lmp) = (void *)(dyn->d_un.d_ptr + base); 2026 break; 2027 case DT_PLTPADSZ: 2028 pltpadsz = dyn->d_un.d_val; 2029 break; 2030 case DT_SUNW_RTLDINF: 2031 /* 2032 * Maintain a list of RTLDINFO structures. 2033 * Typically, libc is the only supplier, and 2034 * only one structure is provided. However, 2035 * multiple suppliers and multiple structures 2036 * are supported. For example, one structure 2037 * may provide thread_init, and another 2038 * structure may provide atexit reservations. 2039 */ 2040 if ((rti = alist_append(&lml->lm_rti, 0, 2041 sizeof (Rti_desc), 2042 AL_CNT_RTLDINFO)) == NULL) { 2043 remove_so(0, lmp); 2044 return (NULL); 2045 } 2046 rti->rti_lmp = lmp; 2047 rti->rti_info = (void *)(dyn->d_un.d_ptr + 2048 base); 2049 break; 2050 case DT_SUNW_SORTENT: 2051 SUNWSORTENT(lmp) = dyn->d_un.d_val; 2052 break; 2053 case DT_SUNW_SYMSORT: 2054 SUNWSYMSORT(lmp) = 2055 (void *)(dyn->d_un.d_ptr + base); 2056 break; 2057 case DT_SUNW_SYMSORTSZ: 2058 SUNWSYMSORTSZ(lmp) = dyn->d_un.d_val; 2059 break; 2060 case DT_DEPRECATED_SPARC_REGISTER: 2061 case M_DT_REGISTER: 2062 FLAGS(lmp) |= FLG_RT_REGSYMS; 2063 break; 2064 } 2065 } 2066 2067 if (PLTPAD(lmp)) { 2068 if (pltpadsz == (Xword)0) 2069 PLTPAD(lmp) = NULL; 2070 else 2071 PLTPADEND(lmp) = (void *)((Addr)PLTPAD(lmp) + 2072 pltpadsz); 2073 } 2074 } 2075 2076 /* 2077 * A dynsym contains only global functions. We want to have 2078 * a version of it that also includes local functions, so that 2079 * dladdr() will be able to report names for local functions 2080 * when used to generate a stack trace for a stripped file. 2081 * This version of the dynsym is provided via DT_SUNW_SYMTAB. 2082 * 2083 * In producing DT_SUNW_SYMTAB, ld uses a non-obvious trick 2084 * in order to avoid having to have two copies of the global 2085 * symbols held in DT_SYMTAB: The local symbols are placed in 2086 * a separate section than the globals in the dynsym, but the 2087 * linker conspires to put the data for these two sections adjacent 2088 * to each other. DT_SUNW_SYMTAB points at the top of the local 2089 * symbols, and DT_SUNW_SYMSZ is the combined length of both tables. 2090 * 2091 * If the two sections are not adjacent, then something went wrong 2092 * at link time. We use ASSERT to kill the process if this is 2093 * a debug build. In a production build, we will silently ignore 2094 * the presence of the .ldynsym and proceed. We can detect this 2095 * situation by checking to see that DT_SYMTAB lies in 2096 * the range given by DT_SUNW_SYMTAB/DT_SUNW_SYMSZ. 2097 */ 2098 if ((SUNWSYMTAB(lmp) != NULL) && 2099 (((char *)SYMTAB(lmp) <= (char *)SUNWSYMTAB(lmp)) || 2100 (((char *)SYMTAB(lmp) >= 2101 (SUNWSYMSZ(lmp) + (char *)SUNWSYMTAB(lmp)))))) { 2102 ASSERT(0); 2103 SUNWSYMTAB(lmp) = NULL; 2104 SUNWSYMSZ(lmp) = 0; 2105 } 2106 2107 /* 2108 * If configuration file use hasn't been disabled, and a configuration 2109 * file hasn't already been set via an environment variable, see if any 2110 * application specific configuration file is specified. An LD_CONFIG 2111 * setting is used first, but if this image was generated via crle(1) 2112 * then a default configuration file is a fall-back. 2113 */ 2114 if ((!(rtld_flags & RT_FL_NOCFG)) && (config->c_name == NULL)) { 2115 if (cfile) 2116 config->c_name = (const char *)(cfile + 2117 (char *)STRTAB(lmp)); 2118 else if (crle) 2119 rtld_flags |= RT_FL_CONFAPP; 2120 } 2121 2122 if (rpath) 2123 RPATH(lmp) = (char *)(rpath + (char *)STRTAB(lmp)); 2124 if (fltr) 2125 REFNAME(lmp) = (char *)(fltr + (char *)STRTAB(lmp)); 2126 2127 /* 2128 * For Intel ABI compatibility. It's possible that a JMPREL can be 2129 * specified without any other relocations (e.g. a dynamic executable 2130 * normally only contains .plt relocations). If this is the case then 2131 * no REL, RELSZ or RELENT will have been created. For us to be able 2132 * to traverse the .plt relocations under LD_BIND_NOW we need to know 2133 * the RELENT for these relocations. Refer to elf_reloc() for more 2134 * details. 2135 */ 2136 if (!RELENT(lmp) && JMPREL(lmp)) 2137 RELENT(lmp) = sizeof (M_RELOC); 2138 2139 /* 2140 * Establish any per-object auditing. If we're establishing `main's 2141 * link-map its too early to go searching for audit objects so just 2142 * hold the object name for later (see setup()). 2143 */ 2144 if (audit) { 2145 char *cp = audit + (char *)STRTAB(lmp); 2146 2147 if (*cp) { 2148 if (((AUDITORS(lmp) = 2149 calloc(1, sizeof (Audit_desc))) == NULL) || 2150 ((AUDITORS(lmp)->ad_name = strdup(cp)) == NULL)) { 2151 remove_so(0, lmp); 2152 return (NULL); 2153 } 2154 if (lml_main.lm_head) { 2155 if (audit_setup(lmp, AUDITORS(lmp), 0, 2156 in_nfavl) == 0) { 2157 remove_so(0, lmp); 2158 return (NULL); 2159 } 2160 AFLAGS(lmp) |= AUDITORS(lmp)->ad_flags; 2161 lml->lm_flags |= LML_FLG_LOCAUDIT; 2162 } 2163 } 2164 } 2165 2166 if (tphdr && (tls_assign(lml, lmp, tphdr) == 0)) { 2167 remove_so(0, lmp); 2168 return (NULL); 2169 } 2170 2171 if (cap) 2172 cap_assign(cap, lmp); 2173 2174 /* 2175 * Add the mapped object to the end of the link map list. 2176 */ 2177 lm_append(lml, lmco, lmp); 2178 2179 /* 2180 * Start the system loading in the ELF information we'll be processing. 2181 */ 2182 if (REL(lmp)) { 2183 (void) madvise((void *)ADDR(lmp), (uintptr_t)REL(lmp) + 2184 (uintptr_t)RELSZ(lmp) - (uintptr_t)ADDR(lmp), 2185 MADV_WILLNEED); 2186 } 2187 return (lmp); 2188 } 2189 2190 /* 2191 * Assign hardware/software capabilities. 2192 */ 2193 void 2194 cap_assign(Cap *cap, Rt_map *lmp) 2195 { 2196 while (cap->c_tag != CA_SUNW_NULL) { 2197 switch (cap->c_tag) { 2198 case CA_SUNW_HW_1: 2199 HWCAP(lmp) = cap->c_un.c_val; 2200 break; 2201 case CA_SUNW_SF_1: 2202 SFCAP(lmp) = cap->c_un.c_val; 2203 } 2204 cap++; 2205 } 2206 } 2207 2208 /* 2209 * Build full pathname of shared object from given directory name and filename. 2210 */ 2211 static char * 2212 elf_get_so(const char *dir, const char *file, size_t dlen, size_t flen) 2213 { 2214 static char pname[PATH_MAX]; 2215 2216 (void) strncpy(pname, dir, dlen); 2217 pname[dlen++] = '/'; 2218 (void) strncpy(&pname[dlen], file, flen + 1); 2219 return (pname); 2220 } 2221 2222 /* 2223 * The copy relocation is recorded in a copy structure which will be applied 2224 * after all other relocations are carried out. This provides for copying data 2225 * that must be relocated itself (ie. pointers in shared objects). This 2226 * structure also provides a means of binding RTLD_GROUP dependencies to any 2227 * copy relocations that have been taken from any group members. 2228 * 2229 * If the size of the .bss area available for the copy information is not the 2230 * same as the source of the data inform the user if we're under ldd(1) control 2231 * (this checking was only established in 5.3, so by only issuing an error via 2232 * ldd(1) we maintain the standard set by previous releases). 2233 */ 2234 int 2235 elf_copy_reloc(char *name, Sym *rsym, Rt_map *rlmp, void *radd, Sym *dsym, 2236 Rt_map *dlmp, const void *dadd) 2237 { 2238 Rel_copy rc; 2239 Lm_list *lml = LIST(rlmp); 2240 2241 rc.r_name = name; 2242 rc.r_rsym = rsym; /* the new reference symbol and its */ 2243 rc.r_rlmp = rlmp; /* associated link-map */ 2244 rc.r_dlmp = dlmp; /* the defining link-map */ 2245 rc.r_dsym = dsym; /* the original definition */ 2246 rc.r_radd = radd; 2247 rc.r_dadd = dadd; 2248 2249 if (rsym->st_size > dsym->st_size) 2250 rc.r_size = (size_t)dsym->st_size; 2251 else 2252 rc.r_size = (size_t)rsym->st_size; 2253 2254 if (alist_append(©_R(dlmp), &rc, sizeof (Rel_copy), 2255 AL_CNT_COPYREL) == NULL) { 2256 if (!(lml->lm_flags & LML_FLG_TRC_WARN)) 2257 return (0); 2258 else 2259 return (1); 2260 } 2261 if (!(FLAGS1(dlmp) & FL1_RT_COPYTOOK)) { 2262 if (aplist_append(©_S(rlmp), dlmp, 2263 AL_CNT_COPYREL) == NULL) { 2264 if (!(lml->lm_flags & LML_FLG_TRC_WARN)) 2265 return (0); 2266 else 2267 return (1); 2268 } 2269 FLAGS1(dlmp) |= FL1_RT_COPYTOOK; 2270 } 2271 2272 /* 2273 * If we are tracing (ldd), warn the user if 2274 * 1) the size from the reference symbol differs from the 2275 * copy definition. We can only copy as much data as the 2276 * reference (dynamic executables) entry allows. 2277 * 2) the copy definition has STV_PROTECTED visibility. 2278 */ 2279 if (lml->lm_flags & LML_FLG_TRC_WARN) { 2280 if (rsym->st_size != dsym->st_size) { 2281 (void) printf(MSG_INTL(MSG_LDD_CPY_SIZDIF), 2282 _conv_reloc_type(M_R_COPY), demangle(name), 2283 NAME(rlmp), EC_XWORD(rsym->st_size), 2284 NAME(dlmp), EC_XWORD(dsym->st_size)); 2285 if (rsym->st_size > dsym->st_size) 2286 (void) printf(MSG_INTL(MSG_LDD_CPY_INSDATA), 2287 NAME(dlmp)); 2288 else 2289 (void) printf(MSG_INTL(MSG_LDD_CPY_DATRUNC), 2290 NAME(rlmp)); 2291 } 2292 2293 if (ELF_ST_VISIBILITY(dsym->st_other) == STV_PROTECTED) { 2294 (void) printf(MSG_INTL(MSG_LDD_CPY_PROT), 2295 _conv_reloc_type(M_R_COPY), demangle(name), 2296 NAME(dlmp)); 2297 } 2298 } 2299 2300 DBG_CALL(Dbg_reloc_apply_val(lml, ELF_DBG_RTLD, (Xword)radd, 2301 (Xword)rc.r_size)); 2302 return (1); 2303 } 2304 2305 /* 2306 * Determine the symbol location of an address within a link-map. Look for 2307 * the nearest symbol (whose value is less than or equal to the required 2308 * address). This is the object specific part of dladdr(). 2309 */ 2310 static void 2311 elf_dladdr(ulong_t addr, Rt_map *lmp, Dl_info *dlip, void **info, int flags) 2312 { 2313 ulong_t ndx, cnt, base, _value; 2314 Sym *sym, *_sym = NULL; 2315 const char *str; 2316 int _flags; 2317 uint_t *dynaddr_ndx; 2318 uint_t dynaddr_n = 0; 2319 ulong_t value; 2320 2321 /* 2322 * If SUNWSYMTAB() is non-NULL, then it sees a special version of 2323 * the dynsym that starts with any local function symbols that exist in 2324 * the library and then moves to the data held in SYMTAB(). In this 2325 * case, SUNWSYMSZ tells us how long the symbol table is. The 2326 * availability of local function symbols will enhance the results 2327 * we can provide. 2328 * 2329 * If SUNWSYMTAB() is non-NULL, then there might also be a 2330 * SUNWSYMSORT() vector associated with it. SUNWSYMSORT() contains 2331 * an array of indices into SUNWSYMTAB, sorted by increasing 2332 * address. We can use this to do an O(log N) search instead of a 2333 * brute force search. 2334 * 2335 * If SUNWSYMTAB() is NULL, then SYMTAB() references a dynsym that 2336 * contains only global symbols. In that case, the length of 2337 * the symbol table comes from the nchain field of the related 2338 * symbol lookup hash table. 2339 */ 2340 str = STRTAB(lmp); 2341 if (SUNWSYMSZ(lmp) == NULL) { 2342 sym = SYMTAB(lmp); 2343 /* 2344 * If we don't have a .hash table there are no symbols 2345 * to look at. 2346 */ 2347 if (HASH(lmp) == NULL) 2348 return; 2349 cnt = HASH(lmp)[1]; 2350 } else { 2351 sym = SUNWSYMTAB(lmp); 2352 cnt = SUNWSYMSZ(lmp) / SYMENT(lmp); 2353 dynaddr_ndx = SUNWSYMSORT(lmp); 2354 if (dynaddr_ndx != NULL) 2355 dynaddr_n = SUNWSYMSORTSZ(lmp) / SUNWSORTENT(lmp); 2356 } 2357 2358 if (FLAGS(lmp) & FLG_RT_FIXED) 2359 base = 0; 2360 else 2361 base = ADDR(lmp); 2362 2363 if (dynaddr_n > 0) { /* Binary search */ 2364 long low = 0, low_bnd; 2365 long high = dynaddr_n - 1, high_bnd; 2366 long mid; 2367 Sym *mid_sym; 2368 2369 /* 2370 * Note that SUNWSYMSORT only contains symbols types that 2371 * supply memory addresses, so there's no need to check and 2372 * filter out any other types. 2373 */ 2374 low_bnd = low; 2375 high_bnd = high; 2376 while (low <= high) { 2377 mid = (low + high) / 2; 2378 mid_sym = &sym[dynaddr_ndx[mid]]; 2379 value = mid_sym->st_value + base; 2380 if (addr < value) { 2381 if ((sym[dynaddr_ndx[high]].st_value + base) >= 2382 addr) 2383 high_bnd = high; 2384 high = mid - 1; 2385 } else if (addr > value) { 2386 if ((sym[dynaddr_ndx[low]].st_value + base) <= 2387 addr) 2388 low_bnd = low; 2389 low = mid + 1; 2390 } else { 2391 _sym = mid_sym; 2392 _value = value; 2393 break; 2394 } 2395 } 2396 /* 2397 * If the above didn't find it exactly, then we must 2398 * return the closest symbol with a value that doesn't 2399 * exceed the one we are looking for. If that symbol exists, 2400 * it will lie in the range bounded by low_bnd and 2401 * high_bnd. This is a linear search, but a short one. 2402 */ 2403 if (_sym == NULL) { 2404 for (mid = low_bnd; mid <= high_bnd; mid++) { 2405 mid_sym = &sym[dynaddr_ndx[mid]]; 2406 value = mid_sym->st_value + base; 2407 if (addr >= value) { 2408 _sym = mid_sym; 2409 _value = value; 2410 } else { 2411 break; 2412 } 2413 } 2414 } 2415 } else { /* Linear search */ 2416 for (_value = 0, sym++, ndx = 1; ndx < cnt; ndx++, sym++) { 2417 /* 2418 * Skip expected symbol types that are not functions 2419 * or data: 2420 * - A symbol table starts with an undefined symbol 2421 * in slot 0. If we are using SUNWSYMTAB(), 2422 * there will be a second undefined symbol 2423 * right before the globals. 2424 * - The local part of SUNWSYMTAB() contains a 2425 * series of function symbols. Each section 2426 * starts with an initial STT_FILE symbol. 2427 */ 2428 if ((sym->st_shndx == SHN_UNDEF) || 2429 (ELF_ST_TYPE(sym->st_info) == STT_FILE)) 2430 continue; 2431 2432 value = sym->st_value + base; 2433 if (value > addr) 2434 continue; 2435 if (value < _value) 2436 continue; 2437 2438 _sym = sym; 2439 _value = value; 2440 2441 /* 2442 * Note, because we accept local and global symbols 2443 * we could find a section symbol that matches the 2444 * associated address, which means that the symbol 2445 * name will be null. In this case continue the 2446 * search in case we can find a global symbol of 2447 * the same value. 2448 */ 2449 if ((value == addr) && 2450 (ELF_ST_TYPE(sym->st_info) != STT_SECTION)) 2451 break; 2452 } 2453 } 2454 2455 _flags = flags & RTLD_DL_MASK; 2456 if (_sym) { 2457 if (_flags == RTLD_DL_SYMENT) 2458 *info = (void *)_sym; 2459 else if (_flags == RTLD_DL_LINKMAP) 2460 *info = (void *)lmp; 2461 2462 dlip->dli_sname = str + _sym->st_name; 2463 dlip->dli_saddr = (void *)_value; 2464 } else { 2465 /* 2466 * addr lies between the beginning of the mapped segment and 2467 * the first global symbol. We have no symbol to return 2468 * and the caller requires one. We use _START_, the base 2469 * address of the mapping. 2470 */ 2471 2472 if (_flags == RTLD_DL_SYMENT) { 2473 /* 2474 * An actual symbol struct is needed, so we 2475 * construct one for _START_. To do this in a 2476 * fully accurate way requires a different symbol 2477 * for each mapped segment. This requires the 2478 * use of dynamic memory and a mutex. That's too much 2479 * plumbing for a fringe case of limited importance. 2480 * 2481 * Fortunately, we can simplify: 2482 * - Only the st_size and st_info fields are useful 2483 * outside of the linker internals. The others 2484 * reference things that outside code cannot see, 2485 * and can be set to 0. 2486 * - It's just a label and there is no size 2487 * to report. So, the size should be 0. 2488 * This means that only st_info needs a non-zero 2489 * (constant) value. A static struct will suffice. 2490 * It must be const (readonly) so the caller can't 2491 * change its meaning for subsequent callers. 2492 */ 2493 static const Sym fsym = { 0, 0, 0, 2494 ELF_ST_INFO(STB_LOCAL, STT_OBJECT) }; 2495 *info = (void *) &fsym; 2496 } 2497 2498 dlip->dli_sname = MSG_ORIG(MSG_SYM_START); 2499 dlip->dli_saddr = (void *) ADDR(lmp); 2500 } 2501 } 2502 2503 static void 2504 elf_lazy_cleanup(APlist *alp) 2505 { 2506 Rt_map *lmp; 2507 Aliste idx; 2508 2509 /* 2510 * Cleanup any link-maps added to this dynamic list and free it. 2511 */ 2512 for (APLIST_TRAVERSE(alp, idx, lmp)) 2513 FLAGS(lmp) &= ~FLG_RT_TMPLIST; 2514 free(alp); 2515 } 2516 2517 /* 2518 * This routine is called as a last fall-back to search for a symbol from a 2519 * standard relocation. To maintain lazy loadings goal of reducing the number 2520 * of objects mapped, any symbol search is first carried out using the objects 2521 * that already exist in the process (either on a link-map list or handle). 2522 * If a symbol can't be found, and lazy dependencies are still pending, this 2523 * routine loads the dependencies in an attempt to locate the symbol. 2524 * 2525 * Only new objects are inspected as we will have already inspected presently 2526 * loaded objects before calling this routine. However, a new object may not 2527 * be new - although the di_lmp might be zero, the object may have been mapped 2528 * as someone elses dependency. Thus there's a possibility of some symbol 2529 * search duplication. 2530 */ 2531 Sym * 2532 elf_lazy_find_sym(Slookup *slp, Rt_map **_lmp, uint_t *binfo, int *in_nfavl) 2533 { 2534 Sym *sym = NULL; 2535 APlist *alist = NULL; 2536 Aliste idx; 2537 Rt_map *lmp1, *lmp = slp->sl_imap; 2538 const char *name = slp->sl_name; 2539 2540 /* 2541 * Generate a local list of new objects to process. This list can grow 2542 * as each object supplies its own lazy dependencies. 2543 */ 2544 if (aplist_append(&alist, lmp, AL_CNT_LAZYFIND) == NULL) 2545 return (NULL); 2546 FLAGS(lmp) |= FLG_RT_TMPLIST; 2547 2548 for (APLIST_TRAVERSE(alist, idx, lmp1)) { 2549 uint_t cnt = 0; 2550 Slookup sl = *slp; 2551 Dyninfo *dip, *pdip; 2552 2553 /* 2554 * Discard any relocation index from further symbol searches. 2555 * This index will have already been used to trigger any 2556 * necessary lazy-loads, and it might be because one of these 2557 * lazy loads have failed that we're here performing this 2558 * fallback. By removing the relocation index we don't try 2559 * and perform the same failed lazy loading activity again. 2560 */ 2561 sl.sl_rsymndx = 0; 2562 2563 /* 2564 * Loop through the lazy DT_NEEDED entries examining each object 2565 * for the required symbol. If the symbol is not found, the 2566 * object is in turn added to the local alist, so that the 2567 * objects lazy DT_NEEDED entries can be examined. 2568 */ 2569 lmp = lmp1; 2570 for (dip = DYNINFO(lmp), pdip = NULL; cnt < DYNINFOCNT(lmp); 2571 cnt++, pdip = dip++) { 2572 Rt_map *nlmp; 2573 2574 if (((dip->di_flags & FLG_DI_LAZY) == 0) || 2575 dip->di_info) 2576 continue; 2577 2578 /* 2579 * If this object has already failed to lazy load, and 2580 * we're still processing the same runtime linker 2581 * operation that produced the failure, don't bother 2582 * to try and load the object again. 2583 */ 2584 if ((dip->di_flags & FLG_DI_LAZYFAIL) && pdip && 2585 (pdip->di_flags & FLG_DI_POSFLAG1)) { 2586 if (pdip->di_info == (void *)ld_entry_cnt) 2587 continue; 2588 2589 dip->di_flags &= ~FLG_DI_LAZYFAIL; 2590 pdip->di_info = NULL; 2591 } 2592 2593 /* 2594 * Try loading this lazy dependency. If the object 2595 * can't be loaded, consider this non-fatal and continue 2596 * the search. Lazy loaded dependencies need not exist 2597 * and their loading should only turn out to be fatal 2598 * if they are required to satisfy a relocation. 2599 * 2600 * If the file is already loaded and relocated we must 2601 * still inspect it for symbols, even though it might 2602 * have already been searched. This lazy load operation 2603 * might have promoted the permissions of the object, 2604 * and thus made the object applicable for this symbol 2605 * search, whereas before the object might have been 2606 * skipped. 2607 */ 2608 if ((nlmp = elf_lazy_load(lmp, &sl, cnt, 2609 name, in_nfavl)) == NULL) 2610 continue; 2611 2612 /* 2613 * If this object isn't yet a part of the dynamic list 2614 * then inspect it for the symbol. If the symbol isn't 2615 * found add the object to the dynamic list so that we 2616 * can inspect its dependencies. 2617 */ 2618 if (FLAGS(nlmp) & FLG_RT_TMPLIST) 2619 continue; 2620 2621 sl.sl_imap = nlmp; 2622 if (sym = LM_LOOKUP_SYM(sl.sl_cmap)(&sl, _lmp, 2623 binfo, in_nfavl)) 2624 break; 2625 2626 /* 2627 * Some dlsym() operations are already traversing a 2628 * link-map (dlopen(0)), and thus there's no need to 2629 * build our own dynamic dependency list. 2630 */ 2631 if ((sl.sl_flags & LKUP_NODESCENT) == 0) { 2632 if (aplist_append(&alist, nlmp, 2633 AL_CNT_LAZYFIND) == NULL) { 2634 elf_lazy_cleanup(alist); 2635 return (NULL); 2636 } 2637 FLAGS(nlmp) |= FLG_RT_TMPLIST; 2638 } 2639 } 2640 if (sym) 2641 break; 2642 } 2643 2644 elf_lazy_cleanup(alist); 2645 return (sym); 2646 } 2647 2648 /* 2649 * Warning message for bad r_offset. 2650 */ 2651 void 2652 elf_reloc_bad(Rt_map *lmp, void *rel, uchar_t rtype, ulong_t roffset, 2653 ulong_t rsymndx) 2654 { 2655 const char *name = NULL; 2656 Lm_list *lml = LIST(lmp); 2657 int trace; 2658 2659 if ((lml->lm_flags & LML_FLG_TRC_ENABLE) && 2660 (((rtld_flags & RT_FL_SILENCERR) == 0) || 2661 (lml->lm_flags & LML_FLG_TRC_VERBOSE))) 2662 trace = 1; 2663 else 2664 trace = 0; 2665 2666 if ((trace == 0) && (DBG_ENABLED == 0)) 2667 return; 2668 2669 if (rsymndx) { 2670 Sym *symref = (Sym *)((ulong_t)SYMTAB(lmp) + 2671 (rsymndx * SYMENT(lmp))); 2672 2673 if (ELF_ST_BIND(symref->st_info) != STB_LOCAL) 2674 name = (char *)(STRTAB(lmp) + symref->st_name); 2675 } 2676 2677 if (name == NULL) 2678 name = MSG_INTL(MSG_STR_UNKNOWN); 2679 2680 if (trace) { 2681 const char *rstr; 2682 2683 rstr = _conv_reloc_type((uint_t)rtype); 2684 (void) printf(MSG_INTL(MSG_LDD_REL_ERR1), rstr, name, 2685 EC_ADDR(roffset)); 2686 return; 2687 } 2688 2689 Dbg_reloc_error(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, name); 2690 } 2691 2692 /* 2693 * Resolve a static TLS relocation. 2694 */ 2695 long 2696 elf_static_tls(Rt_map *lmp, Sym *sym, void *rel, uchar_t rtype, char *name, 2697 ulong_t roffset, long value) 2698 { 2699 Lm_list *lml = LIST(lmp); 2700 2701 /* 2702 * Relocations against a static TLS block have limited support once 2703 * process initialization has completed. Any error condition should be 2704 * discovered by testing for DF_STATIC_TLS as part of loading an object, 2705 * however individual relocations are tested in case the dynamic flag 2706 * had not been set when this object was built. 2707 */ 2708 if (PTTLS(lmp) == NULL) { 2709 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, 2710 M_REL_SHT_TYPE, rel, NULL, name)); 2711 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS), 2712 _conv_reloc_type((uint_t)rtype), NAME(lmp), 2713 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN)); 2714 return (0); 2715 } 2716 2717 /* 2718 * If no static TLS has been set aside for this object, determine if 2719 * any can be obtained. Enforce that any object using static TLS is 2720 * non-deletable. 2721 */ 2722 if (TLSSTATOFF(lmp) == 0) { 2723 FLAGS1(lmp) |= FL1_RT_TLSSTAT; 2724 MODE(lmp) |= RTLD_NODELETE; 2725 2726 if (tls_assign(lml, lmp, PTTLS(lmp)) == 0) { 2727 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, 2728 M_REL_SHT_TYPE, rel, NULL, name)); 2729 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS), 2730 _conv_reloc_type((uint_t)rtype), NAME(lmp), 2731 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN)); 2732 return (0); 2733 } 2734 } 2735 2736 /* 2737 * Typically, a static TLS offset is maintained as a symbols value. 2738 * For local symbols that are not apart of the dynamic symbol table, 2739 * the TLS relocation points to a section symbol, and the static TLS 2740 * offset was deposited in the associated GOT table. Make sure the GOT 2741 * is cleared, so that the value isn't reused in do_reloc(). 2742 */ 2743 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) { 2744 if ((ELF_ST_TYPE(sym->st_info) == STT_SECTION)) { 2745 value = *(long *)roffset; 2746 *(long *)roffset = 0; 2747 } else { 2748 value = sym->st_value; 2749 } 2750 } 2751 return (-(TLSSTATOFF(lmp) - value)); 2752 } 2753 2754 /* 2755 * If the symbol is not found and the reference was not to a weak symbol, report 2756 * an error. Weak references may be unresolved. 2757 */ 2758 int 2759 elf_reloc_error(Rt_map *lmp, const char *name, void *rel, uint_t binfo) 2760 { 2761 Lm_list *lml = LIST(lmp); 2762 2763 /* 2764 * Under crle(1), relocation failures are ignored. 2765 */ 2766 if (lml->lm_flags & LML_FLG_IGNRELERR) 2767 return (1); 2768 2769 /* 2770 * Under ldd(1), unresolved references are reported. However, if the 2771 * original reference is EXTERN or PARENT these references are ignored 2772 * unless ldd's -p option is in effect. 2773 */ 2774 if (lml->lm_flags & LML_FLG_TRC_WARN) { 2775 if (((binfo & DBG_BINFO_REF_MSK) == 0) || 2776 ((lml->lm_flags & LML_FLG_TRC_NOPAREXT) != 0)) { 2777 (void) printf(MSG_INTL(MSG_LDD_SYM_NFOUND), 2778 demangle(name), NAME(lmp)); 2779 } 2780 return (1); 2781 } 2782 2783 /* 2784 * Otherwise, the unresolved references is fatal. 2785 */ 2786 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, 2787 NULL, name)); 2788 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp), 2789 demangle(name)); 2790 2791 return (0); 2792 } 2793 2794 /* 2795 * Generic relative relocation function. 2796 */ 2797 inline static ulong_t 2798 _elf_reloc_relative(ulong_t rbgn, ulong_t base, Rt_map *lmp, APlist **textrel) 2799 { 2800 mmapobj_result_t *mpp; 2801 ulong_t roffset; 2802 2803 roffset = ((M_RELOC *)rbgn)->r_offset; 2804 roffset += base; 2805 2806 /* 2807 * If this relocation is against an address that is not associated with 2808 * a mapped segment, fall back to the generic relocation loop to 2809 * collect the associated error. 2810 */ 2811 if ((mpp = find_segment((caddr_t)roffset, lmp)) == NULL) 2812 return (0); 2813 2814 /* 2815 * If this relocation is against a segment that does not provide write 2816 * access, set the write permission for all non-writable mappings. 2817 */ 2818 if (((mpp->mr_prot & PROT_WRITE) == 0) && textrel && 2819 ((set_prot(lmp, mpp, 1) == 0) || 2820 (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) 2821 return (0); 2822 2823 /* 2824 * Perform the actual relocation. Note, for backward compatibility, 2825 * SPARC relocations are added to the offset contents (there was a time 2826 * when the offset was used to contain the addend, rather than using 2827 * the addend itself). 2828 */ 2829 #if defined(__sparc) 2830 *((ulong_t *)roffset) += base + ((M_RELOC *)rbgn)->r_addend; 2831 #elif defined(__amd64) 2832 *((ulong_t *)roffset) = base + ((M_RELOC *)rbgn)->r_addend; 2833 #else 2834 *((ulong_t *)roffset) += base; 2835 #endif 2836 return (1); 2837 } 2838 2839 /* 2840 * When a generic relocation loop realizes that it's dealing with relative 2841 * relocations, but no DT_RELCOUNT .dynamic tag is present, this tighter loop 2842 * is entered as an optimization. 2843 */ 2844 ulong_t 2845 elf_reloc_relative(ulong_t rbgn, ulong_t rend, ulong_t rsize, ulong_t base, 2846 Rt_map *lmp, APlist **textrel) 2847 { 2848 char rtype; 2849 2850 do { 2851 if (_elf_reloc_relative(rbgn, base, lmp, textrel) == 0) 2852 break; 2853 2854 rbgn += rsize; 2855 if (rbgn >= rend) 2856 break; 2857 2858 /* 2859 * Make sure the next type is a relative relocation. 2860 */ 2861 rtype = ELF_R_TYPE(((M_RELOC *)rbgn)->r_info, M_MACH); 2862 2863 } while (rtype == M_R_RELATIVE); 2864 2865 return (rbgn); 2866 } 2867 2868 /* 2869 * This is the tightest loop for RELATIVE relocations for those objects built 2870 * with the DT_RELACOUNT .dynamic entry. 2871 */ 2872 ulong_t 2873 elf_reloc_relative_count(ulong_t rbgn, ulong_t rcount, ulong_t rsize, 2874 ulong_t base, Rt_map *lmp, APlist **textrel) 2875 { 2876 for (; rcount; rcount--) { 2877 if (_elf_reloc_relative(rbgn, base, lmp, textrel) == 0) 2878 break; 2879 2880 rbgn += rsize; 2881 } 2882 return (rbgn); 2883 } 2884