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 (c) 1988 AT&T
24 * All Rights Reserved
25 *
26 * Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
27 */
28 /*
29 * Copyright (c) 2012, Joyent, Inc. 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_gen.h"
49 #include "_inline_reloc.h"
50 #include "msg.h"
51
52 /*
53 * Default and secure dependency search paths.
54 */
55 static Spath_defn _elf_def_dirs[] = {
56 #if defined(_ELF64)
57 { MSG_ORIG(MSG_PTH_LIB_64), MSG_PTH_LIB_64_SIZE },
58 { MSG_ORIG(MSG_PTH_USRLIB_64), MSG_PTH_USRLIB_64_SIZE },
59 #else
60 { MSG_ORIG(MSG_PTH_LIB), MSG_PTH_LIB_SIZE },
61 { MSG_ORIG(MSG_PTH_USRLIB), MSG_PTH_USRLIB_SIZE },
62 #endif
63 { 0, 0 }
64 };
65
66 static Spath_defn _elf_sec_dirs[] = {
67 #if defined(_ELF64)
68 { MSG_ORIG(MSG_PTH_LIBSE_64), MSG_PTH_LIBSE_64_SIZE },
69 { MSG_ORIG(MSG_PTH_USRLIBSE_64), MSG_PTH_USRLIBSE_64_SIZE },
70 #else
71 { MSG_ORIG(MSG_PTH_LIBSE), MSG_PTH_LIBSE_SIZE },
72 { MSG_ORIG(MSG_PTH_USRLIBSE), MSG_PTH_USRLIBSE_SIZE },
73 #endif
74 { 0, 0 }
75 };
76
77 Alist *elf_def_dirs = NULL;
78 Alist *elf_sec_dirs = NULL;
79
80 /*
81 * Defines for local functions.
82 */
83 static void elf_dladdr(ulong_t, Rt_map *, Dl_info *, void **, int);
84 static Addr elf_entry_point(void);
85 static int elf_fix_name(const char *, Rt_map *, Alist **, Aliste, uint_t);
86 static Alist **elf_get_def_dirs(void);
87 static Alist **elf_get_sec_dirs(void);
88 static char *elf_get_so(const char *, const char *, size_t, size_t);
89 static int elf_needed(Lm_list *, Aliste, Rt_map *, int *);
90
91 /*
92 * Functions and data accessed through indirect pointers.
93 */
94 Fct elf_fct = {
95 elf_verify,
96 elf_new_lmp,
97 elf_entry_point,
98 elf_needed,
99 lookup_sym,
100 elf_reloc,
101 elf_get_def_dirs,
102 elf_get_sec_dirs,
103 elf_fix_name,
104 elf_get_so,
105 elf_dladdr,
106 dlsym_handle
107 };
108
109 /*
110 * Default and secure dependency search paths.
111 */
112 static Alist **
113 elf_get_def_dirs()
114 {
115 if (elf_def_dirs == NULL)
116 set_dirs(&elf_def_dirs, _elf_def_dirs, LA_SER_DEFAULT);
117 return (&elf_def_dirs);
118 }
119
120 static Alist **
121 elf_get_sec_dirs()
122 {
123 if (elf_sec_dirs == NULL)
124 set_dirs(&elf_sec_dirs, _elf_sec_dirs, LA_SER_SECURE);
125 return (&elf_sec_dirs);
126 }
127
128 /*
129 * Redefine NEEDED name if necessary.
130 */
131 static int
132 elf_fix_name(const char *name, Rt_map *clmp, Alist **alpp, Aliste alni,
133 uint_t orig)
134 {
135 /*
136 * For ABI compliance, if we are asked for ld.so.1, then really give
137 * them libsys.so.1 (the SONAME of libsys.so.1 is ld.so.1).
138 */
139 if (((*name == '/') &&
140 /* BEGIN CSTYLED */
141 #if defined(_ELF64)
142 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD_64)) == 0)) ||
143 #else
144 (strcmp(name, MSG_ORIG(MSG_PTH_RTLD)) == 0)) ||
145 #endif
146 (strcmp(name, MSG_ORIG(MSG_FIL_RTLD)) == 0)) {
147 /* END CSTYLED */
148 Pdesc *pdp;
149
150 DBG_CALL(Dbg_file_fixname(LIST(clmp), name,
151 MSG_ORIG(MSG_PTH_LIBSYS)));
152 if ((pdp = alist_append(alpp, NULL, sizeof (Pdesc),
153 alni)) == NULL)
154 return (0);
155
156 pdp->pd_pname = (char *)MSG_ORIG(MSG_PTH_LIBSYS);
157 pdp->pd_plen = MSG_PTH_LIBSYS_SIZE;
158 pdp->pd_flags = PD_FLG_PNSLASH;
159
160 return (1);
161 }
162
163 return (expand_paths(clmp, name, alpp, alni, orig, 0));
164 }
165
166 /*
167 * Determine whether this object requires capabilities.
168 */
169 inline static int
170 elf_cap_check(Fdesc *fdp, Ehdr *ehdr, Rej_desc *rej)
171 {
172 Phdr *phdr;
173 Cap *cap = NULL;
174 Dyn *dyn = NULL;
175 char *str = NULL;
176 Addr base;
177 uint_t cnt, dyncnt;
178
179 /*
180 * If this is a shared object, the base address of the shared object is
181 * added to all address values defined within the object. Otherwise, if
182 * this is an executable, all object addresses are used as is.
183 */
184 if (ehdr->e_type == ET_EXEC)
185 base = 0;
186 else
187 base = (Addr)ehdr;
188
189 /* LINTED */
190 phdr = (Phdr *)((char *)ehdr + ehdr->e_phoff);
191 for (cnt = 0; cnt < ehdr->e_phnum; cnt++, phdr++) {
192 if (phdr->p_type == PT_DYNAMIC) {
193 /* LINTED */
194 dyn = (Dyn *)((uintptr_t)phdr->p_vaddr + base);
195 dyncnt = phdr->p_filesz / sizeof (Dyn);
196 } else if (phdr->p_type == PT_SUNWCAP) {
197 /* LINTED */
198 cap = (Cap *)((uintptr_t)phdr->p_vaddr + base);
199 }
200 }
201
202 if (cap) {
203 /*
204 * From the .dynamic section, determine the associated string
205 * table. Required for CA_SUNW_MACH and CA_SUNW_PLAT
206 * processing.
207 */
208 while (dyn && dyncnt) {
209 if (dyn->d_tag == DT_NULL) {
210 break;
211 } else if (dyn->d_tag == DT_STRTAB) {
212 str = (char *)(dyn->d_un.d_ptr + base);
213 break;
214 }
215 dyn++, dyncnt--;
216 }
217 }
218
219 /*
220 * Establish any alternative capabilities, and validate this object
221 * if it defines it's own capabilities information.
222 */
223 return (cap_check_fdesc(fdp, cap, str, rej));
224 }
225
226 /*
227 * Determine if we have been given an ELF file and if so determine if the file
228 * is compatible. Returns 1 if true, else 0 and sets the reject descriptor
229 * with associated error information.
230 */
231 Fct *
232 elf_verify(caddr_t addr, size_t size, Fdesc *fdp, const char *name,
233 Rej_desc *rej)
234 {
235 Ehdr *ehdr;
236 char *caddr = (char *)addr;
237
238 /*
239 * Determine if we're an elf file. If not simply return, we don't set
240 * any rejection information as this test allows use to scroll through
241 * the objects we support (ELF, AOUT).
242 */
243 if (size < sizeof (Ehdr) ||
244 caddr[EI_MAG0] != ELFMAG0 ||
245 caddr[EI_MAG1] != ELFMAG1 ||
246 caddr[EI_MAG2] != ELFMAG2 ||
247 caddr[EI_MAG3] != ELFMAG3) {
248 return (NULL);
249 }
250
251 /*
252 * Check class and encoding.
253 */
254 /* LINTED */
255 ehdr = (Ehdr *)addr;
256 if (ehdr->e_ident[EI_CLASS] != M_CLASS) {
257 rej->rej_type = SGS_REJ_CLASS;
258 rej->rej_info = (uint_t)ehdr->e_ident[EI_CLASS];
259 return (NULL);
260 }
261 if (ehdr->e_ident[EI_DATA] != M_DATA) {
262 rej->rej_type = SGS_REJ_DATA;
263 rej->rej_info = (uint_t)ehdr->e_ident[EI_DATA];
264 return (NULL);
265 }
266 if ((ehdr->e_type != ET_REL) && (ehdr->e_type != ET_EXEC) &&
267 (ehdr->e_type != ET_DYN)) {
268 rej->rej_type = SGS_REJ_TYPE;
269 rej->rej_info = (uint_t)ehdr->e_type;
270 return (NULL);
271 }
272
273 /*
274 * Verify ELF version.
275 */
276 if (ehdr->e_version > EV_CURRENT) {
277 rej->rej_type = SGS_REJ_VERSION;
278 rej->rej_info = (uint_t)ehdr->e_version;
279 return (NULL);
280 }
281
282 /*
283 * Verify machine specific flags.
284 */
285 if (elf_mach_flags_check(rej, ehdr) == 0)
286 return (NULL);
287
288 /*
289 * Verify any capability requirements. Note, if this object is a shared
290 * object that is explicitly defined on the ldd(1) command line, and it
291 * contains an incompatible capabilities requirement, then inform the
292 * user, but continue processing.
293 */
294 if (elf_cap_check(fdp, ehdr, rej) == 0) {
295 Rt_map *lmp = lml_main.lm_head;
296
297 if ((lml_main.lm_flags & LML_FLG_TRC_LDDSTUB) && lmp &&
298 (FLAGS1(lmp) & FL1_RT_LDDSTUB) && (NEXT(lmp) == NULL)) {
299 /* LINTED */
300 (void) printf(MSG_INTL(ldd_warn[rej->rej_type]), name,
301 rej->rej_str);
302 return (&elf_fct);
303 }
304 return (NULL);
305 }
306 return (&elf_fct);
307 }
308
309 /*
310 * The runtime linker employs lazy loading to provide the libraries needed for
311 * debugging, preloading .o's and dldump(). As these are seldom used, the
312 * standard startup of ld.so.1 doesn't initialize all the information necessary
313 * to perform plt relocation on ld.so.1's link-map. The first time lazy loading
314 * is called we get here to perform these initializations:
315 *
316 * - elf_needed() is called to establish any ld.so.1 dependencies. These
317 * dependencies should all be lazy loaded, so this routine is typically a
318 * no-op. However, we call elf_needed() for completeness, in case any
319 * NEEDED initialization is required.
320 *
321 * - For intel, ld.so.1's JMPSLOT relocations need relative updates. These
322 * are by default skipped thus delaying all relative relocation processing
323 * on every invocation of ld.so.1.
324 */
325 int
326 elf_rtld_load()
327 {
328 Lm_list *lml = &lml_rtld;
329 Rt_map *lmp = lml->lm_head;
330
331 if (lml->lm_flags & LML_FLG_PLTREL)
332 return (1);
333
334 if (elf_needed(lml, ALIST_OFF_DATA, lmp, NULL) == 0)
335 return (0);
336
337 #if defined(__i386)
338 /*
339 * This is a kludge to give ld.so.1 a performance benefit on i386.
340 * It's based around two factors.
341 *
342 * - JMPSLOT relocations (PLT's) actually need a relative relocation
343 * applied to the GOT entry so that they can find PLT0.
344 *
345 * - ld.so.1 does not exercise *any* PLT's before it has made a call
346 * to elf_lazy_load(). This is because all dynamic dependencies
347 * are recorded as lazy dependencies.
348 */
349 (void) elf_reloc_relative_count((ulong_t)JMPREL(lmp),
350 (ulong_t)(PLTRELSZ(lmp) / RELENT(lmp)), (ulong_t)RELENT(lmp),
351 (ulong_t)ADDR(lmp), lmp, NULL, 0);
352 #endif
353 lml->lm_flags |= LML_FLG_PLTREL;
354 return (1);
355 }
356
357 /*
358 * Lazy load an object.
359 */
360 Rt_map *
361 elf_lazy_load(Rt_map *clmp, Slookup *slp, uint_t ndx, const char *sym,
362 uint_t flags, Grp_hdl **hdl, int *in_nfavl)
363 {
364 Alist *palp = NULL;
365 Rt_map *nlmp;
366 Dyninfo *dip = &DYNINFO(clmp)[ndx], *pdip;
367 const char *name;
368 Lm_list *lml = LIST(clmp);
369 Aliste lmco;
370
371 /*
372 * If this dependency should be ignored, or has already been processed,
373 * we're done.
374 */
375 if (((nlmp = (Rt_map *)dip->di_info) != NULL) ||
376 (dip->di_flags & (FLG_DI_IGNORE | FLG_DI_LDD_DONE)))
377 return (nlmp);
378
379 /*
380 * If we're running under ldd(1), indicate that this dependency has been
381 * processed (see test above). It doesn't matter whether the object is
382 * successfully loaded or not, this flag simply ensures that we don't
383 * repeatedly attempt to load an object that has already failed to load.
384 * To do so would create multiple failure diagnostics for the same
385 * object under ldd(1).
386 */
387 if (lml->lm_flags & LML_FLG_TRC_ENABLE)
388 dip->di_flags |= FLG_DI_LDD_DONE;
389
390 /*
391 * Determine the initial dependency name.
392 */
393 name = dip->di_name;
394 DBG_CALL(Dbg_file_lazyload(clmp, name, sym));
395
396 /*
397 * If this object needs to establish its own group, make sure a handle
398 * is created.
399 */
400 if (dip->di_flags & FLG_DI_GROUP)
401 flags |= (FLG_RT_SETGROUP | FLG_RT_PUBHDL);
402
403 /*
404 * Lazy dependencies are identified as DT_NEEDED entries with a
405 * DF_P1_LAZYLOAD flag in the previous DT_POSFLAG_1 element. The
406 * dynamic information element that corresponds to the DT_POSFLAG_1
407 * entry is free, and thus used to store the present entrance
408 * identifier. This identifier is used to prevent multiple attempts to
409 * load a failed lazy loadable dependency within the same runtime linker
410 * operation. However, future attempts to reload this dependency are
411 * still possible.
412 */
413 if (ndx && (pdip = dip - 1) && (pdip->di_flags & FLG_DI_POSFLAG1))
414 pdip->di_info = (void *)slp->sl_id;
415
416 /*
417 * Expand the requested name if necessary.
418 */
419 if (elf_fix_name(name, clmp, &palp, AL_CNT_NEEDED, 0) == 0)
420 return (NULL);
421
422 /*
423 * Establish a link-map control list for this request.
424 */
425 if ((lmco = create_cntl(lml, 0)) == NULL) {
426 remove_alist(&palp, 1);
427 return (NULL);
428 }
429
430 /*
431 * Load the associated object.
432 */
433 dip->di_info = nlmp =
434 load_one(lml, lmco, palp, clmp, MODE(clmp), flags, hdl, in_nfavl);
435
436 /*
437 * Remove any expanded pathname infrastructure. Reduce the pending lazy
438 * dependency count of the caller, together with the link-map lists
439 * count of objects that still have lazy dependencies pending.
440 */
441 remove_alist(&palp, 1);
442 if (--LAZY(clmp) == 0)
443 LIST(clmp)->lm_lazy--;
444
445 /*
446 * Finish processing the objects associated with this request, and
447 * create an association between the caller and this dependency.
448 */
449 if (nlmp && ((bind_one(clmp, nlmp, BND_NEEDED) == 0) ||
450 ((nlmp = analyze_lmc(lml, lmco, nlmp, clmp, in_nfavl)) == NULL) ||
451 (relocate_lmc(lml, lmco, clmp, nlmp, in_nfavl) == 0)))
452 dip->di_info = nlmp = NULL;
453
454 /*
455 * If this lazyload has failed, and we've created a new link-map
456 * control list to which this request has added objects, then remove
457 * all the objects that have been associated to this request.
458 */
459 if ((nlmp == NULL) && (lmco != ALIST_OFF_DATA))
460 remove_lmc(lml, clmp, lmco, name);
461
462 /*
463 * Remove any temporary link-map control list.
464 */
465 if (lmco != ALIST_OFF_DATA)
466 remove_cntl(lml, lmco);
467
468 /*
469 * If this lazy loading failed, record the fact, and bump the lazy
470 * counts.
471 */
472 if (nlmp == NULL) {
473 dip->di_flags |= FLG_DI_LAZYFAIL;
474 if (LAZY(clmp)++ == 0)
475 LIST(clmp)->lm_lazy++;
476 }
477
478 return (nlmp);
479 }
480
481 /*
482 * Return the entry point of the ELF executable.
483 */
484 static Addr
485 elf_entry_point(void)
486 {
487 Rt_map *lmp = lml_main.lm_head;
488 Ehdr *ehdr = (Ehdr *)ADDR(lmp);
489 Addr addr = (Addr)(ehdr->e_entry);
490
491 if ((FLAGS(lmp) & FLG_RT_FIXED) == 0)
492 addr += ADDR(lmp);
493
494 return (addr);
495 }
496
497 /*
498 * Determine if a dependency requires a particular version and if so verify
499 * that the version exists in the dependency.
500 */
501 int
502 elf_verify_vers(const char *name, Rt_map *clmp, Rt_map *nlmp)
503 {
504 Verneed *vnd = VERNEED(clmp);
505 int _num, num = VERNEEDNUM(clmp);
506 char *cstrs = (char *)STRTAB(clmp);
507 Lm_list *lml = LIST(clmp);
508
509 /*
510 * Traverse the callers version needed information and determine if any
511 * specific versions are required from the dependency.
512 */
513 DBG_CALL(Dbg_ver_need_title(LIST(clmp), NAME(clmp)));
514 for (_num = 1; _num <= num; _num++,
515 vnd = (Verneed *)((Xword)vnd + vnd->vn_next)) {
516 Half cnt = vnd->vn_cnt;
517 Vernaux *vnap;
518 char *nstrs, *need;
519
520 /*
521 * Determine if a needed entry matches this dependency.
522 */
523 need = (char *)(cstrs + vnd->vn_file);
524 if (strcmp(name, need) != 0)
525 continue;
526
527 if ((lml->lm_flags & LML_FLG_TRC_VERBOSE) &&
528 ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0))
529 (void) printf(MSG_INTL(MSG_LDD_VER_FIND), name);
530
531 /*
532 * Validate that each version required actually exists in the
533 * dependency.
534 */
535 nstrs = (char *)STRTAB(nlmp);
536
537 for (vnap = (Vernaux *)((Xword)vnd + vnd->vn_aux); cnt;
538 cnt--, vnap = (Vernaux *)((Xword)vnap + vnap->vna_next)) {
539 char *version, *define;
540 Verdef *vdf = VERDEF(nlmp);
541 ulong_t _num, num = VERDEFNUM(nlmp);
542 int found = 0;
543
544 /*
545 * Skip validation of versions that are marked
546 * INFO. This optimization is used for versions
547 * that are inherited by another version. Verification
548 * of the inheriting version is sufficient.
549 *
550 * Such versions are recorded in the object for the
551 * benefit of VERSYM entries that refer to them. This
552 * provides a purely diagnostic benefit.
553 */
554 if (vnap->vna_flags & VER_FLG_INFO)
555 continue;
556
557 version = (char *)(cstrs + vnap->vna_name);
558 DBG_CALL(Dbg_ver_need_entry(lml, 0, need, version));
559
560 for (_num = 1; _num <= num; _num++,
561 vdf = (Verdef *)((Xword)vdf + vdf->vd_next)) {
562 Verdaux *vdap;
563
564 if (vnap->vna_hash != vdf->vd_hash)
565 continue;
566
567 vdap = (Verdaux *)((Xword)vdf + vdf->vd_aux);
568 define = (char *)(nstrs + vdap->vda_name);
569 if (strcmp(version, define) != 0)
570 continue;
571
572 found++;
573 break;
574 }
575
576 /*
577 * If we're being traced print out any matched version
578 * when the verbose (-v) option is in effect. Always
579 * print any unmatched versions.
580 */
581 if (lml->lm_flags & LML_FLG_TRC_ENABLE) {
582 /* BEGIN CSTYLED */
583 if (found) {
584 if (!(lml->lm_flags & LML_FLG_TRC_VERBOSE))
585 continue;
586
587 (void) printf(MSG_ORIG(MSG_LDD_VER_FOUND),
588 need, version, NAME(nlmp));
589 } else {
590 if (rtld_flags & RT_FL_SILENCERR)
591 continue;
592
593 (void) printf(MSG_INTL(MSG_LDD_VER_NFOUND),
594 need, version);
595 }
596 /* END CSTYLED */
597 continue;
598 }
599
600 /*
601 * If the version hasn't been found then this is a
602 * candidate for a fatal error condition. Weak
603 * version definition requirements are silently
604 * ignored. Also, if the image inspected for a version
605 * definition has no versioning recorded at all then
606 * silently ignore this (this provides better backward
607 * compatibility to old images created prior to
608 * versioning being available). Both of these skipped
609 * diagnostics are available under tracing (see above).
610 */
611 if ((found == 0) && (num != 0) &&
612 (!(vnap->vna_flags & VER_FLG_WEAK))) {
613 eprintf(lml, ERR_FATAL,
614 MSG_INTL(MSG_VER_NFOUND), need, version,
615 NAME(clmp));
616 return (0);
617 }
618 }
619 }
620 DBG_CALL(Dbg_ver_need_done(lml));
621 return (1);
622 }
623
624 /*
625 * Search through the dynamic section for DT_NEEDED entries and perform one
626 * of two functions. If only the first argument is specified then load the
627 * defined shared object, otherwise add the link map representing the defined
628 * link map the the dlopen list.
629 */
630 static int
631 elf_needed(Lm_list *lml, Aliste lmco, Rt_map *clmp, int *in_nfavl)
632 {
633 Alist *palp = NULL;
634 Dyn *dyn;
635 Dyninfo *dip;
636 Word lmflags = lml->lm_flags;
637
638 /*
639 * A DYNINFO() structure is created during link-map generation that
640 * parallels the DYN() information, and defines any flags that
641 * influence a dependencies loading.
642 */
643 for (dyn = DYN(clmp), dip = DYNINFO(clmp);
644 !(dip->di_flags & FLG_DI_IGNORE); dyn++, dip++) {
645 uint_t flags = 0, silent = 0;
646 const char *name = dip->di_name;
647 Rt_map *nlmp = NULL;
648
649 if ((dip->di_flags & FLG_DI_NEEDED) == 0)
650 continue;
651
652 /*
653 * Skip any deferred dependencies, unless ldd(1) has forced
654 * their processing. By default, deferred dependencies are
655 * only processed when an explicit binding to an individual
656 * deferred reference is made.
657 */
658 if ((dip->di_flags & FLG_DI_DEFERRED) &&
659 ((rtld_flags & RT_FL_DEFERRED) == 0))
660 continue;
661
662 /*
663 * NOTE, libc.so.1 can't be lazy loaded. Although a lazy
664 * position flag won't be produced when a RTLDINFO .dynamic
665 * entry is found (introduced with the UPM in Solaris 10), it
666 * was possible to mark libc for lazy loading on previous
667 * releases. To reduce the overhead of testing for this
668 * occurrence, only carry out this check for the first object
669 * on the link-map list (there aren't many applications built
670 * without libc).
671 */
672 if ((dip->di_flags & FLG_DI_LAZY) && (lml->lm_head == clmp) &&
673 (strcmp(name, MSG_ORIG(MSG_FIL_LIBC)) == 0))
674 dip->di_flags &= ~FLG_DI_LAZY;
675
676 /*
677 * Don't bring in lazy loaded objects yet unless we've been
678 * asked to attempt to load all available objects (crle(1) sets
679 * LD_FLAGS=loadavail). Even under RTLD_NOW we don't process
680 * this - RTLD_NOW will cause relocation processing which in
681 * turn might trigger lazy loading, but its possible that the
682 * object has a lazy loaded file with no bindings (i.e., it
683 * should never have been a dependency in the first place).
684 */
685 if (dip->di_flags & FLG_DI_LAZY) {
686 if ((lmflags & LML_FLG_LOADAVAIL) == 0) {
687 LAZY(clmp)++;
688 continue;
689 }
690
691 /*
692 * Silence any error messages - see description under
693 * elf_lookup_filtee().
694 */
695 if ((rtld_flags & RT_FL_SILENCERR) == 0) {
696 rtld_flags |= RT_FL_SILENCERR;
697 silent = 1;
698 }
699 }
700
701 DBG_CALL(Dbg_file_needed(clmp, name));
702
703 /*
704 * If we're running under ldd(1), indicate that this dependency
705 * has been processed. It doesn't matter whether the object is
706 * successfully loaded or not, this flag simply ensures that we
707 * don't repeatedly attempt to load an object that has already
708 * failed to load. To do so would create multiple failure
709 * diagnostics for the same object under ldd(1).
710 */
711 if (lml->lm_flags & LML_FLG_TRC_ENABLE)
712 dip->di_flags |= FLG_DI_LDD_DONE;
713
714 /*
715 * Identify any group permission requirements.
716 */
717 if (dip->di_flags & FLG_DI_GROUP)
718 flags = (FLG_RT_SETGROUP | FLG_RT_PUBHDL);
719
720 /*
721 * Establish the objects name, load it and establish a binding
722 * with the caller.
723 */
724 if ((elf_fix_name(name, clmp, &palp, AL_CNT_NEEDED, 0) == 0) ||
725 ((nlmp = load_one(lml, lmco, palp, clmp, MODE(clmp),
726 flags, 0, in_nfavl)) == NULL) ||
727 (bind_one(clmp, nlmp, BND_NEEDED) == 0))
728 nlmp = NULL;
729
730 /*
731 * Clean up any infrastructure, including the removal of the
732 * error suppression state, if it had been previously set in
733 * this routine.
734 */
735 remove_alist(&palp, 0);
736
737 if (silent)
738 rtld_flags &= ~RT_FL_SILENCERR;
739
740 if ((dip->di_info = (void *)nlmp) == NULL) {
741 /*
742 * If the object could not be mapped, continue if error
743 * suppression is established or we're here with ldd(1).
744 */
745 if ((MODE(clmp) & RTLD_CONFGEN) || (lmflags &
746 (LML_FLG_LOADAVAIL | LML_FLG_TRC_ENABLE)))
747 continue;
748 else {
749 remove_alist(&palp, 1);
750 return (0);
751 }
752 }
753 }
754
755 if (LAZY(clmp))
756 lml->lm_lazy++;
757
758 remove_alist(&palp, 1);
759 return (1);
760 }
761
762 /*
763 * A null symbol interpretor. Used if a filter has no associated filtees.
764 */
765 /* ARGSUSED0 */
766 static int
767 elf_null_find_sym(Slookup *slp, Sresult *srp, uint_t *binfo, int *in_nfavl)
768 {
769 return (0);
770 }
771
772 /*
773 * Disable filtee use.
774 */
775 static void
776 elf_disable_filtee(Rt_map *lmp, Dyninfo *dip)
777 {
778 if ((dip->di_flags & FLG_DI_SYMFLTR) == 0) {
779 /*
780 * If this is an object filter, null out the reference name.
781 */
782 if (OBJFLTRNDX(lmp) != FLTR_DISABLED) {
783 REFNAME(lmp) = NULL;
784 OBJFLTRNDX(lmp) = FLTR_DISABLED;
785
786 /*
787 * Indicate that this filtee is no longer available.
788 */
789 if (dip->di_flags & FLG_DI_STDFLTR)
790 SYMINTP(lmp) = elf_null_find_sym;
791
792 }
793 } else if (dip->di_flags & FLG_DI_STDFLTR) {
794 /*
795 * Indicate that this standard filtee is no longer available.
796 */
797 if (SYMSFLTRCNT(lmp))
798 SYMSFLTRCNT(lmp)--;
799 } else {
800 /*
801 * Indicate that this auxiliary filtee is no longer available.
802 */
803 if (SYMAFLTRCNT(lmp))
804 SYMAFLTRCNT(lmp)--;
805 }
806 dip->di_flags &= ~MSK_DI_FILTER;
807 }
808
809 /*
810 * Find symbol interpreter - filters.
811 * This function is called when the symbols from a shared object should
812 * be resolved from the shared objects filtees instead of from within itself.
813 *
814 * A symbol name of 0 is used to trigger filtee loading.
815 */
816 static int
817 _elf_lookup_filtee(Slookup *slp, Sresult *srp, uint_t *binfo, uint_t ndx,
818 int *in_nfavl)
819 {
820 const char *name = slp->sl_name, *filtees;
821 Rt_map *clmp = slp->sl_cmap;
822 Rt_map *ilmp = slp->sl_imap;
823 Pdesc *pdp;
824 int any;
825 Dyninfo *dip = &DYNINFO(ilmp)[ndx];
826 Lm_list *lml = LIST(ilmp);
827 Aliste idx;
828
829 /*
830 * Indicate that the filter has been used. If a binding already exists
831 * to the caller, indicate that this object is referenced. This insures
832 * we don't generate false unreferenced diagnostics from ldd -u/U or
833 * debugging. Don't create a binding regardless, as this filter may
834 * have been dlopen()'ed.
835 */
836 if (name && (ilmp != clmp)) {
837 Word tracing = (LIST(clmp)->lm_flags &
838 (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED));
839
840 if (tracing || DBG_ENABLED) {
841 Bnd_desc *bdp;
842 Aliste idx;
843
844 FLAGS1(ilmp) |= FL1_RT_USED;
845
846 if ((tracing & LML_FLG_TRC_UNREF) || DBG_ENABLED) {
847 for (APLIST_TRAVERSE(CALLERS(ilmp), idx, bdp)) {
848 if (bdp->b_caller == clmp) {
849 bdp->b_flags |= BND_REFER;
850 break;
851 }
852 }
853 }
854 }
855 }
856
857 /*
858 * If this is the first call to process this filter, establish the
859 * filtee list. If a configuration file exists, determine if any
860 * filtee associations for this filter, and its filtee reference, are
861 * defined. Otherwise, process the filtee reference. Any token
862 * expansion is also completed at this point (i.e., $PLATFORM).
863 */
864 filtees = dip->di_name;
865 if (dip->di_info == NULL) {
866 if (rtld_flags2 & RT_FL2_FLTCFG) {
867 elf_config_flt(lml, PATHNAME(ilmp), filtees,
868 (Alist **)&dip->di_info, AL_CNT_FILTEES);
869 }
870 if (dip->di_info == NULL) {
871 DBG_CALL(Dbg_file_filter(lml, NAME(ilmp), filtees, 0));
872 if ((lml->lm_flags &
873 (LML_FLG_TRC_VERBOSE | LML_FLG_TRC_SEARCH)) &&
874 ((FLAGS1(ilmp) & FL1_RT_LDDSTUB) == 0))
875 (void) printf(MSG_INTL(MSG_LDD_FIL_FILTER),
876 NAME(ilmp), filtees);
877
878 if (expand_paths(ilmp, filtees, (Alist **)&dip->di_info,
879 AL_CNT_FILTEES, 0, 0) == 0) {
880 elf_disable_filtee(ilmp, dip);
881 return (0);
882 }
883 }
884 }
885
886 /*
887 * Traverse the filtee list, dlopen()'ing any objects specified and
888 * using their group handle to lookup the symbol.
889 */
890 any = 0;
891 for (ALIST_TRAVERSE((Alist *)dip->di_info, idx, pdp)) {
892 int mode;
893 Grp_hdl *ghp;
894 Rt_map *nlmp = NULL;
895
896 if (pdp->pd_plen == 0)
897 continue;
898
899 /*
900 * Establish the mode of the filtee from the filter. As filtees
901 * are loaded via a dlopen(), make sure that RTLD_GROUP is set
902 * and the filtees aren't global. It would be nice to have
903 * RTLD_FIRST used here also, but as filters got out long before
904 * RTLD_FIRST was introduced it's a little too late now.
905 */
906 mode = MODE(ilmp) | RTLD_GROUP;
907 mode &= ~RTLD_GLOBAL;
908
909 /*
910 * Insure that any auxiliary filter can locate symbols from its
911 * caller.
912 */
913 if (dip->di_flags & FLG_DI_AUXFLTR)
914 mode |= RTLD_PARENT;
915
916 /*
917 * Process any capability directory. Establish a new link-map
918 * control list from which to analyze any newly added objects.
919 */
920 if ((pdp->pd_info == NULL) && (pdp->pd_flags & PD_TKN_CAP)) {
921 const char *dir = pdp->pd_pname;
922 Aliste lmco;
923
924 /*
925 * Establish a link-map control list for this request.
926 */
927 if ((lmco = create_cntl(lml, 0)) == NULL)
928 return (NULL);
929
930 /*
931 * Determine the capability filtees. If none can be
932 * found, provide suitable diagnostics.
933 */
934 DBG_CALL(Dbg_cap_filter(lml, dir, ilmp));
935 if (cap_filtees((Alist **)&dip->di_info, idx, dir,
936 lmco, ilmp, clmp, filtees, mode,
937 (FLG_RT_PUBHDL | FLG_RT_CAP), in_nfavl) == 0) {
938 if ((lml->lm_flags & LML_FLG_TRC_ENABLE) &&
939 (dip->di_flags & FLG_DI_AUXFLTR) &&
940 (rtld_flags & RT_FL_WARNFLTR)) {
941 (void) printf(
942 MSG_INTL(MSG_LDD_CAP_NFOUND), dir);
943 }
944 DBG_CALL(Dbg_cap_filter(lml, dir, 0));
945 }
946
947 /*
948 * Re-establish the originating path name descriptor,
949 * as the expansion of capabilities filtees may have
950 * re-allocated the controlling Alist. Mark this
951 * original pathname descriptor as unused so that the
952 * descriptor isn't revisited for processing. Any real
953 * capabilities filtees have been added as new pathname
954 * descriptors following this descriptor.
955 */
956 pdp = alist_item((Alist *)dip->di_info, idx);
957 pdp->pd_flags &= ~PD_TKN_CAP;
958 pdp->pd_plen = 0;
959
960 /*
961 * Now that any capability objects have been processed,
962 * remove any temporary link-map control list.
963 */
964 if (lmco != ALIST_OFF_DATA)
965 remove_cntl(lml, lmco);
966 }
967
968 if (pdp->pd_plen == 0)
969 continue;
970
971 /*
972 * Process an individual filtee.
973 */
974 if (pdp->pd_info == NULL) {
975 const char *filtee = pdp->pd_pname;
976 int audit = 0;
977
978 DBG_CALL(Dbg_file_filtee(lml, NAME(ilmp), filtee, 0));
979
980 ghp = NULL;
981
982 /*
983 * Determine if the reference link map is already
984 * loaded. As an optimization compare the filtee with
985 * our interpretor. The most common filter is
986 * libdl.so.1, which is a filter on ld.so.1.
987 */
988 #if defined(_ELF64)
989 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD_64)) == 0) {
990 #else
991 if (strcmp(filtee, MSG_ORIG(MSG_PTH_RTLD)) == 0) {
992 #endif
993 uint_t hflags, rdflags, cdflags;
994
995 /*
996 * Establish any flags for the handle (Grp_hdl).
997 *
998 * - This is a special, public, ld.so.1
999 * handle.
1000 * - Only the first object on this handle
1001 * can supply symbols.
1002 * - This handle provides a filtee.
1003 *
1004 * Essentially, this handle allows a caller to
1005 * reference the dl*() family of interfaces from
1006 * ld.so.1.
1007 */
1008 hflags = (GPH_PUBLIC | GPH_LDSO |
1009 GPH_FIRST | GPH_FILTEE);
1010
1011 /*
1012 * Establish the flags for the referenced
1013 * dependency descriptor (Grp_desc).
1014 *
1015 * - ld.so.1 is available for dlsym().
1016 * - ld.so.1 is available to relocate
1017 * against.
1018 * - There's no need to add an dependencies
1019 * to this handle.
1020 */
1021 rdflags = (GPD_DLSYM | GPD_RELOC);
1022
1023 /*
1024 * Establish the flags for this callers
1025 * dependency descriptor (Grp_desc).
1026 *
1027 * - The explicit creation of a handle
1028 * creates a descriptor for the referenced
1029 * object and the parent (caller).
1030 */
1031 cdflags = GPD_PARENT;
1032
1033 nlmp = lml_rtld.lm_head;
1034 if ((ghp = hdl_create(&lml_rtld, nlmp, ilmp,
1035 hflags, rdflags, cdflags)) == NULL)
1036 nlmp = NULL;
1037
1038 /*
1039 * Establish the filter handle to prevent any
1040 * recursion.
1041 */
1042 if (nlmp && ghp)
1043 pdp->pd_info = (void *)ghp;
1044
1045 /*
1046 * Audit the filter/filtee established. Ignore
1047 * any return from the auditor, as we can't
1048 * allow ignore filtering to ld.so.1, otherwise
1049 * nothing is going to work.
1050 */
1051 if (nlmp && ((lml->lm_tflags | AFLAGS(ilmp)) &
1052 LML_TFLG_AUD_OBJFILTER))
1053 (void) audit_objfilter(ilmp, filtees,
1054 nlmp, 0);
1055
1056 } else {
1057 Rej_desc rej = { 0 };
1058 Fdesc fd = { 0 };
1059 Aliste lmco;
1060
1061 /*
1062 * Trace the inspection of this file, determine
1063 * any auditor substitution, and seed the file
1064 * descriptor with the originating name.
1065 */
1066 if (load_trace(lml, pdp, clmp, &fd) == NULL)
1067 continue;
1068
1069 /*
1070 * Establish a link-map control list for this
1071 * request.
1072 */
1073 if ((lmco = create_cntl(lml, 0)) == NULL)
1074 return (NULL);
1075
1076 /*
1077 * Locate and load the filtee.
1078 */
1079 if ((nlmp = load_path(lml, lmco, ilmp, mode,
1080 FLG_RT_PUBHDL, &ghp, &fd, &rej,
1081 in_nfavl)) == NULL)
1082 file_notfound(LIST(ilmp), filtee, ilmp,
1083 FLG_RT_PUBHDL, &rej);
1084
1085 filtee = pdp->pd_pname;
1086
1087 /*
1088 * Establish the filter handle to prevent any
1089 * recursion.
1090 */
1091 if (nlmp && ghp) {
1092 ghp->gh_flags |= GPH_FILTEE;
1093 pdp->pd_info = (void *)ghp;
1094
1095 FLAGS1(nlmp) |= FL1_RT_USED;
1096 }
1097
1098 /*
1099 * Audit the filter/filtee established. A
1100 * return of 0 indicates the auditor wishes to
1101 * ignore this filtee.
1102 */
1103 if (nlmp && ((lml->lm_tflags | FLAGS1(ilmp)) &
1104 LML_TFLG_AUD_OBJFILTER)) {
1105 if (audit_objfilter(ilmp, filtees,
1106 nlmp, 0) == 0) {
1107 audit = 1;
1108 nlmp = NULL;
1109 }
1110 }
1111
1112 /*
1113 * Finish processing the objects associated with
1114 * this request. Create an association between
1115 * this object and the originating filter to
1116 * provide sufficient information to tear down
1117 * this filtee if necessary.
1118 */
1119 if (nlmp && ghp && (((nlmp = analyze_lmc(lml,
1120 lmco, nlmp, clmp, in_nfavl)) == NULL) ||
1121 (relocate_lmc(lml, lmco, ilmp, nlmp,
1122 in_nfavl) == 0)))
1123 nlmp = NULL;
1124
1125 /*
1126 * If the filtee has been successfully
1127 * processed, then create an association
1128 * between the filter and filtee. This
1129 * association provides sufficient information
1130 * to tear down the filter and filtee if
1131 * necessary.
1132 */
1133 DBG_CALL(Dbg_file_hdl_title(DBG_HDL_ADD));
1134 if (nlmp && ghp && (hdl_add(ghp, ilmp,
1135 GPD_FILTER, NULL) == NULL))
1136 nlmp = NULL;
1137
1138 /*
1139 * Generate a diagnostic if the filtee couldn't
1140 * be loaded.
1141 */
1142 if (nlmp == NULL)
1143 DBG_CALL(Dbg_file_filtee(lml, 0, filtee,
1144 audit));
1145
1146 /*
1147 * If this filtee loading has failed, and we've
1148 * created a new link-map control list to which
1149 * this request has added objects, then remove
1150 * all the objects that have been associated to
1151 * this request.
1152 */
1153 if ((nlmp == NULL) && (lmco != ALIST_OFF_DATA))
1154 remove_lmc(lml, clmp, lmco, name);
1155
1156 /*
1157 * Remove any temporary link-map control list.
1158 */
1159 if (lmco != ALIST_OFF_DATA)
1160 remove_cntl(lml, lmco);
1161 }
1162
1163 /*
1164 * If the filtee couldn't be loaded, null out the
1165 * path name descriptor entry, and continue the search.
1166 * Otherwise, the group handle is retained for future
1167 * symbol searches.
1168 */
1169 if (nlmp == NULL) {
1170 pdp->pd_info = NULL;
1171 pdp->pd_plen = 0;
1172 continue;
1173 }
1174 }
1175
1176 ghp = (Grp_hdl *)pdp->pd_info;
1177
1178 /*
1179 * If name is NULL, we're here to trigger filtee loading.
1180 * Skip the symbol lookup so that we'll continue looking for
1181 * additional filtees.
1182 */
1183 if (name) {
1184 Grp_desc *gdp;
1185 int ret = 0;
1186 Aliste idx;
1187 Slookup sl = *slp;
1188
1189 sl.sl_flags |= (LKUP_FIRST | LKUP_DLSYM);
1190 any++;
1191
1192 /*
1193 * Look for the symbol in the handles dependencies.
1194 */
1195 for (ALIST_TRAVERSE(ghp->gh_depends, idx, gdp)) {
1196 if ((gdp->gd_flags & GPD_DLSYM) == 0)
1197 continue;
1198
1199 /*
1200 * If our parent is a dependency don't look at
1201 * it (otherwise we are in a recursive loop).
1202 * This situation can occur with auxiliary
1203 * filters if the filtee has a dependency on the
1204 * filter. This dependency isn't necessary as
1205 * auxiliary filters are opened RTLD_PARENT, but
1206 * users may still unknowingly add an explicit
1207 * dependency to the parent.
1208 */
1209 if ((sl.sl_imap = gdp->gd_depend) == ilmp)
1210 continue;
1211
1212 if (((ret = SYMINTP(sl.sl_imap)(&sl, srp, binfo,
1213 in_nfavl)) != 0) ||
1214 (ghp->gh_flags & GPH_FIRST))
1215 break;
1216 }
1217
1218 /*
1219 * If a symbol has been found, indicate the binding
1220 * and return the symbol.
1221 */
1222 if (ret) {
1223 *binfo |= DBG_BINFO_FILTEE;
1224 return (1);
1225 }
1226 }
1227
1228 /*
1229 * If this object is tagged to terminate filtee processing we're
1230 * done.
1231 */
1232 if (FLAGS1(ghp->gh_ownlmp) & FL1_RT_ENDFILTE)
1233 break;
1234 }
1235
1236 /*
1237 * If we're just here to trigger filtee loading then we're done.
1238 */
1239 if (name == NULL)
1240 return (0);
1241
1242 /*
1243 * If no filtees have been found for a filter, clean up any path name
1244 * descriptors and disable their search completely. For auxiliary
1245 * filters we can reselect the symbol search function so that we never
1246 * enter this routine again for this object. For standard filters we
1247 * use the null symbol routine.
1248 */
1249 if (any == 0) {
1250 remove_alist((Alist **)&(dip->di_info), 1);
1251 elf_disable_filtee(ilmp, dip);
1252 }
1253
1254 return (0);
1255 }
1256
1257 /*
1258 * Focal point for disabling error messages for auxiliary filters. As an
1259 * auxiliary filter allows for filtee use, but provides a fallback should a
1260 * filtee not exist (or fail to load), any errors generated as a consequence of
1261 * trying to load the filtees are typically suppressed. Setting RT_FL_SILENCERR
1262 * suppresses errors generated by eprintf(), but ensures a debug diagnostic is
1263 * produced. ldd(1) employs printf(), and here the selection of whether to
1264 * print a diagnostic in regards to auxiliary filters is a little more complex.
1265 *
1266 * - The determination of whether to produce an ldd message, or a fatal
1267 * error message is driven by LML_FLG_TRC_ENABLE.
1268 * - More detailed ldd messages may also be driven off of LML_FLG_TRC_WARN,
1269 * (ldd -d/-r), LML_FLG_TRC_VERBOSE (ldd -v), LML_FLG_TRC_SEARCH (ldd -s),
1270 * and LML_FLG_TRC_UNREF/LML_FLG_TRC_UNUSED (ldd -U/-u).
1271 * - If the calling object is lddstub, then several classes of message are
1272 * suppressed. The user isn't trying to diagnose lddstub, this is simply
1273 * a stub executable employed to preload a user specified library against.
1274 * - If RT_FL_SILENCERR is in effect then any generic ldd() messages should
1275 * be suppressed. All detailed ldd messages should still be produced.
1276 */
1277 int
1278 elf_lookup_filtee(Slookup *slp, Sresult *srp, uint_t *binfo, uint_t ndx,
1279 int *in_nfavl)
1280 {
1281 Dyninfo *dip = &DYNINFO(slp->sl_imap)[ndx];
1282 int ret, silent = 0;
1283
1284 /*
1285 * Make sure this entry is still acting as a filter. We may have tried
1286 * to process this previously, and disabled it if the filtee couldn't
1287 * be processed. However, other entries may provide different filtees
1288 * that are yet to be completed.
1289 */
1290 if (dip->di_flags == 0)
1291 return (0);
1292
1293 /*
1294 * Indicate whether an error message is required should this filtee not
1295 * be found, based on the type of filter.
1296 */
1297 if ((dip->di_flags & FLG_DI_AUXFLTR) &&
1298 ((rtld_flags & (RT_FL_WARNFLTR | RT_FL_SILENCERR)) == 0)) {
1299 rtld_flags |= RT_FL_SILENCERR;
1300 silent = 1;
1301 }
1302
1303 ret = _elf_lookup_filtee(slp, srp, binfo, ndx, in_nfavl);
1304
1305 if (silent)
1306 rtld_flags &= ~RT_FL_SILENCERR;
1307
1308 return (ret);
1309 }
1310
1311 /*
1312 * Compute the elf hash value (as defined in the ELF access library).
1313 * The form of the hash table is:
1314 *
1315 * |--------------|
1316 * | # of buckets |
1317 * |--------------|
1318 * | # of chains |
1319 * |--------------|
1320 * | bucket[] |
1321 * |--------------|
1322 * | chain[] |
1323 * |--------------|
1324 */
1325 ulong_t
1326 elf_hash(const char *name)
1327 {
1328 uint_t hval = 0;
1329
1330 while (*name) {
1331 uint_t g;
1332 hval = (hval << 4) + *name++;
1333 if ((g = (hval & 0xf0000000)) != 0)
1334 hval ^= g >> 24;
1335 hval &= ~g;
1336 }
1337 return ((ulong_t)hval);
1338 }
1339
1340 /*
1341 * Look up a symbol. The callers lookup information is passed in the Slookup
1342 * structure, and any resultant binding information is returned in the Sresult
1343 * structure.
1344 */
1345 int
1346 elf_find_sym(Slookup *slp, Sresult *srp, uint_t *binfo, int *in_nfavl)
1347 {
1348 const char *name = slp->sl_name;
1349 Rt_map *ilmp = slp->sl_imap;
1350 ulong_t hash = slp->sl_hash;
1351 uint_t ndx, hashoff, buckets, *chainptr;
1352 Sym *sym, *symtabptr;
1353 char *strtabptr, *strtabname;
1354 uint_t flags1;
1355 Syminfo *sip;
1356
1357 /*
1358 * If we're only here to establish a symbols index, skip the diagnostic
1359 * used to trace a symbol search.
1360 */
1361 if ((slp->sl_flags & LKUP_SYMNDX) == 0)
1362 DBG_CALL(Dbg_syms_lookup(ilmp, name, MSG_ORIG(MSG_STR_ELF)));
1363
1364 if (HASH(ilmp) == NULL)
1365 return (0);
1366
1367 buckets = HASH(ilmp)[0];
1368 /* LINTED */
1369 hashoff = ((uint_t)hash % buckets) + 2;
1370
1371 /*
1372 * Get the first symbol from the hash chain and initialize the string
1373 * and symbol table pointers.
1374 */
1375 if ((ndx = HASH(ilmp)[hashoff]) == 0)
1376 return (0);
1377
1378 chainptr = HASH(ilmp) + 2 + buckets;
1379 strtabptr = STRTAB(ilmp);
1380 symtabptr = SYMTAB(ilmp);
1381
1382 while (ndx) {
1383 sym = symtabptr + ndx;
1384 strtabname = strtabptr + sym->st_name;
1385
1386 /*
1387 * Compare the symbol found with the name required. If the
1388 * names don't match continue with the next hash entry.
1389 */
1390 if ((*strtabname++ != *name) || strcmp(strtabname, &name[1])) {
1391 hashoff = ndx + buckets + 2;
1392 if ((ndx = chainptr[ndx]) != 0)
1393 continue;
1394 return (0);
1395 }
1396
1397 /*
1398 * Symbols that are defined as hidden within an object usually
1399 * have any references from within the same object bound at
1400 * link-edit time, thus ld.so.1 is not involved. However, if
1401 * these are capabilities symbols, then references to them must
1402 * be resolved at runtime. A hidden symbol can only be bound
1403 * to by the object that defines the symbol.
1404 */
1405 if ((sym->st_shndx != SHN_UNDEF) &&
1406 (ELF_ST_VISIBILITY(sym->st_other) == STV_HIDDEN) &&
1407 (slp->sl_cmap != ilmp))
1408 return (0);
1409
1410 /*
1411 * The Solaris ld does not put DT_VERSYM in the dynamic
1412 * section, but the GNU ld does. The GNU runtime linker
1413 * interprets the top bit of the 16-bit Versym value
1414 * (0x8000) as the "hidden" bit. If this bit is set,
1415 * the linker is supposed to act as if that symbol does
1416 * not exist. The hidden bit supports their versioning
1417 * scheme, which allows multiple incompatible functions
1418 * with the same name to exist at different versions
1419 * within an object. The Solaris linker does not support this
1420 * mechanism, or the model of interface evolution that
1421 * it allows, but we honor the hidden bit in GNU ld
1422 * produced objects in order to interoperate with them.
1423 */
1424 if (VERSYM(ilmp) && (VERSYM(ilmp)[ndx] & 0x8000)) {
1425 DBG_CALL(Dbg_syms_ignore_gnuver(ilmp, name,
1426 ndx, VERSYM(ilmp)[ndx]));
1427 return (0);
1428 }
1429
1430 /*
1431 * If we're only here to establish a symbol's index, we're done.
1432 */
1433 if (slp->sl_flags & LKUP_SYMNDX) {
1434 srp->sr_dmap = ilmp;
1435 srp->sr_sym = sym;
1436 return (1);
1437 }
1438
1439 /*
1440 * If we find a match and the symbol is defined, capture the
1441 * symbol pointer and the link map in which it was found.
1442 */
1443 if (sym->st_shndx != SHN_UNDEF) {
1444 srp->sr_dmap = ilmp;
1445 srp->sr_sym = sym;
1446 *binfo |= DBG_BINFO_FOUND;
1447
1448 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) ||
1449 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) &&
1450 is_sym_interposer(ilmp, sym)))
1451 *binfo |= DBG_BINFO_INTERPOSE;
1452 break;
1453
1454 /*
1455 * If we find a match and the symbol is undefined, the
1456 * symbol type is a function, and the value of the symbol
1457 * is non zero, then this is a special case. This allows
1458 * the resolution of a function address to the plt[] entry.
1459 * See SPARC ABI, Dynamic Linking, Function Addresses for
1460 * more details.
1461 */
1462 } else if ((slp->sl_flags & LKUP_SPEC) &&
1463 (FLAGS(ilmp) & FLG_RT_ISMAIN) && (sym->st_value != 0) &&
1464 (ELF_ST_TYPE(sym->st_info) == STT_FUNC)) {
1465 srp->sr_dmap = ilmp;
1466 srp->sr_sym = sym;
1467 *binfo |= (DBG_BINFO_FOUND | DBG_BINFO_PLTADDR);
1468
1469 if ((FLAGS(ilmp) & FLG_RT_OBJINTPO) ||
1470 ((FLAGS(ilmp) & FLG_RT_SYMINTPO) &&
1471 is_sym_interposer(ilmp, sym)))
1472 *binfo |= DBG_BINFO_INTERPOSE;
1473 return (1);
1474 }
1475
1476 /*
1477 * Undefined symbol.
1478 */
1479 return (0);
1480 }
1481
1482 /*
1483 * We've found a match. Determine if the defining object contains
1484 * symbol binding information.
1485 */
1486 if ((sip = SYMINFO(ilmp)) != NULL)
1487 sip += ndx;
1488
1489 /*
1490 * If this definition is a singleton, and we haven't followed a default
1491 * symbol search knowing that we're looking for a singleton (presumably
1492 * because the symbol definition has been changed since the referring
1493 * object was built), then reject this binding so that the caller can
1494 * fall back to a standard symbol search.
1495 */
1496 if ((ELF_ST_VISIBILITY(sym->st_other) == STV_SINGLETON) &&
1497 (((slp->sl_flags & LKUP_STANDARD) == 0) ||
1498 (((slp->sl_flags & LKUP_SINGLETON) == 0) &&
1499 (LIST(ilmp)->lm_flags & LML_FLG_GROUPSEXIST)))) {
1500 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name,
1501 DBG_BNDREJ_SINGLE));
1502 *binfo |= BINFO_REJSINGLE;
1503 *binfo &= ~DBG_BINFO_MSK;
1504 return (0);
1505 }
1506
1507 /*
1508 * If this is a direct binding request, but the symbol definition has
1509 * disabled directly binding to it (presumably because the symbol
1510 * definition has been changed since the referring object was built),
1511 * reject this binding so that the caller can fall back to a standard
1512 * symbol search.
1513 */
1514 if (sip && (slp->sl_flags & LKUP_DIRECT) &&
1515 (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT)) {
1516 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name,
1517 DBG_BNDREJ_DIRECT));
1518 *binfo |= BINFO_REJDIRECT;
1519 *binfo &= ~DBG_BINFO_MSK;
1520 return (0);
1521 }
1522
1523 /*
1524 * If this is a binding request within an RTLD_GROUP family, and the
1525 * symbol has disabled directly binding to it, reject this binding so
1526 * that the caller can fall back to a standard symbol search.
1527 *
1528 * Effectively, an RTLD_GROUP family achieves what can now be
1529 * established with direct bindings. However, various symbols have
1530 * been tagged as inappropriate for direct binding to (ie. libc:malloc).
1531 *
1532 * A symbol marked as no-direct cannot be used within a group without
1533 * first ensuring that the symbol has not been interposed upon outside
1534 * of the group. A common example occurs when users implement their own
1535 * version of malloc() in the executable. Such a malloc() interposes on
1536 * the libc:malloc, and this interposition must be honored within the
1537 * group as well.
1538 *
1539 * Following any rejection, LKUP_WORLD is established as a means of
1540 * overriding this test as we return to a standard search.
1541 */
1542 if (sip && (sip->si_flags & SYMINFO_FLG_NOEXTDIRECT) &&
1543 ((MODE(slp->sl_cmap) & (RTLD_GROUP | RTLD_WORLD)) == RTLD_GROUP) &&
1544 ((slp->sl_flags & LKUP_WORLD) == 0)) {
1545 DBG_CALL(Dbg_bind_reject(slp->sl_cmap, ilmp, name,
1546 DBG_BNDREJ_GROUP));
1547 *binfo |= BINFO_REJGROUP;
1548 *binfo &= ~DBG_BINFO_MSK;
1549 return (0);
1550 }
1551
1552 /*
1553 * If this symbol is associated with capabilities, then each of the
1554 * capabilities instances needs to be compared against the system
1555 * capabilities. The best instance will be chosen to satisfy this
1556 * binding.
1557 */
1558 if (CAP(ilmp) && CAPINFO(ilmp) && ELF_C_GROUP(CAPINFO(ilmp)[ndx]) &&
1559 (cap_match(srp, ndx, symtabptr, strtabptr) == 0))
1560 return (0);
1561
1562 /*
1563 * Determine whether this object is acting as a filter.
1564 */
1565 if (((flags1 = FLAGS1(ilmp)) & MSK_RT_FILTER) == 0)
1566 return (1);
1567
1568 /*
1569 * Determine if this object offers per-symbol filtering, and if so,
1570 * whether this symbol references a filtee.
1571 */
1572 if (sip && (flags1 & (FL1_RT_SYMSFLTR | FL1_RT_SYMAFLTR))) {
1573 /*
1574 * If this is a standard filter reference, and no standard
1575 * filtees remain to be inspected, we're done. If this is an
1576 * auxiliary filter reference, and no auxiliary filtees remain,
1577 * we'll fall through in case any object filtering is available.
1578 */
1579 if ((sip->si_flags & SYMINFO_FLG_FILTER) &&
1580 (SYMSFLTRCNT(ilmp) == 0))
1581 return (0);
1582
1583 if ((sip->si_flags & SYMINFO_FLG_FILTER) ||
1584 ((sip->si_flags & SYMINFO_FLG_AUXILIARY) &&
1585 SYMAFLTRCNT(ilmp))) {
1586 Sresult sr;
1587
1588 /*
1589 * Initialize a local symbol result descriptor, using
1590 * the original symbol name.
1591 */
1592 SRESULT_INIT(sr, slp->sl_name);
1593
1594 /*
1595 * This symbol has an associated filtee. Lookup the
1596 * symbol in the filtee, and if it is found return it.
1597 * If the symbol doesn't exist, and this is a standard
1598 * filter, return an error, otherwise fall through to
1599 * catch any object filtering that may be available.
1600 */
1601 if (elf_lookup_filtee(slp, &sr, binfo, sip->si_boundto,
1602 in_nfavl)) {
1603 *srp = sr;
1604 return (1);
1605 }
1606 if (sip->si_flags & SYMINFO_FLG_FILTER)
1607 return (0);
1608 }
1609 }
1610
1611 /*
1612 * Determine if this object provides global filtering.
1613 */
1614 if (flags1 & (FL1_RT_OBJSFLTR | FL1_RT_OBJAFLTR)) {
1615 if (OBJFLTRNDX(ilmp) != FLTR_DISABLED) {
1616 Sresult sr;
1617
1618 /*
1619 * Initialize a local symbol result descriptor, using
1620 * the original symbol name.
1621 */
1622 SRESULT_INIT(sr, slp->sl_name);
1623
1624 /*
1625 * This object has an associated filtee. Lookup the
1626 * symbol in the filtee, and if it is found return it.
1627 * If the symbol doesn't exist, and this is a standard
1628 * filter, return and error, otherwise return the symbol
1629 * within the filter itself.
1630 */
1631 if (elf_lookup_filtee(slp, &sr, binfo, OBJFLTRNDX(ilmp),
1632 in_nfavl)) {
1633 *srp = sr;
1634 return (1);
1635 }
1636 }
1637
1638 if (flags1 & FL1_RT_OBJSFLTR)
1639 return (0);
1640 }
1641 return (1);
1642 }
1643
1644 /*
1645 * Create a new Rt_map structure for an ELF object and initialize
1646 * all values.
1647 */
1648 Rt_map *
1649 elf_new_lmp(Lm_list *lml, Aliste lmco, Fdesc *fdp, Addr addr, size_t msize,
1650 void *odyn, Rt_map *clmp, int *in_nfavl)
1651 {
1652 const char *name = fdp->fd_nname;
1653 Rt_map *lmp;
1654 Ehdr *ehdr = (Ehdr *)addr;
1655 Phdr *phdr, *tphdr = NULL, *dphdr = NULL, *uphdr = NULL;
1656 Dyn *dyn = (Dyn *)odyn;
1657 Cap *cap = NULL;
1658 int ndx;
1659 Addr base, fltr = 0, audit = 0, cfile = 0, crle = 0;
1660 Xword rpath = 0;
1661 size_t lmsz, rtsz, epsz, dynsz = 0;
1662 uint_t dyncnt = 0;
1663
1664 DBG_CALL(Dbg_file_elf(lml, name, addr, msize, lml->lm_lmidstr, lmco));
1665
1666 /*
1667 * If this is a shared object, the base address of the shared object is
1668 * added to all address values defined within the object. Otherwise, if
1669 * this is an executable, all object addresses are used as is.
1670 */
1671 if (ehdr->e_type == ET_EXEC)
1672 base = 0;
1673 else
1674 base = addr;
1675
1676 /*
1677 * Traverse the program header table, picking off required items. This
1678 * traversal also provides for the sizing of the PT_DYNAMIC section.
1679 */
1680 phdr = (Phdr *)((uintptr_t)ehdr + ehdr->e_phoff);
1681 for (ndx = 0; ndx < (int)ehdr->e_phnum; ndx++,
1682 phdr = (Phdr *)((uintptr_t)phdr + ehdr->e_phentsize)) {
1683 switch (phdr->p_type) {
1684 case PT_DYNAMIC:
1685 dphdr = phdr;
1686 dyn = (Dyn *)((uintptr_t)phdr->p_vaddr + base);
1687 break;
1688 case PT_TLS:
1689 tphdr = phdr;
1690 break;
1691 case PT_SUNWCAP:
1692 cap = (Cap *)((uintptr_t)phdr->p_vaddr + base);
1693 break;
1694 case PT_SUNW_UNWIND:
1695 case PT_SUNW_EH_FRAME:
1696 uphdr = phdr;
1697 break;
1698 default:
1699 break;
1700 }
1701 }
1702
1703 /*
1704 * Determine the number of PT_DYNAMIC entries for the DYNINFO()
1705 * allocation. Sadly, this is a little larger than we really need,
1706 * as there are typically padding DT_NULL entries. However, adding
1707 * this data to the initial link-map allocation is a win.
1708 */
1709 if (dyn) {
1710 dyncnt = dphdr->p_filesz / sizeof (Dyn);
1711 dynsz = dyncnt * sizeof (Dyninfo);
1712 }
1713
1714 /*
1715 * Allocate space for the link-map, private elf information, and
1716 * DYNINFO() data. Once these are allocated and initialized,
1717 * remove_so(0, lmp) can be used to tear down the link-map allocation
1718 * should any failures occur.
1719 */
1720 rtsz = S_DROUND(sizeof (Rt_map));
1721 epsz = S_DROUND(sizeof (Rt_elfp));
1722 lmsz = rtsz + epsz + dynsz;
1723 if ((lmp = calloc(lmsz, 1)) == NULL)
1724 return (NULL);
1725 ELFPRV(lmp) = (void *)((uintptr_t)lmp + rtsz);
1726 DYNINFO(lmp) = (Dyninfo *)((uintptr_t)lmp + rtsz + epsz);
1727 LMSIZE(lmp) = lmsz;
1728
1729 /*
1730 * All fields not filled in were set to 0 by calloc.
1731 */
1732 NAME(lmp) = (char *)name;
1733 ADDR(lmp) = addr;
1734 MSIZE(lmp) = msize;
1735 SYMINTP(lmp) = elf_find_sym;
1736 FCT(lmp) = &elf_fct;
1737 LIST(lmp) = lml;
1738 OBJFLTRNDX(lmp) = FLTR_DISABLED;
1739 SORTVAL(lmp) = -1;
1740 DYN(lmp) = dyn;
1741 DYNINFOCNT(lmp) = dyncnt;
1742 PTUNWIND(lmp) = uphdr;
1743
1744 if (ehdr->e_type == ET_EXEC)
1745 FLAGS(lmp) |= FLG_RT_FIXED;
1746
1747 /*
1748 * Fill in rest of the link map entries with information from the file's
1749 * dynamic structure.
1750 */
1751 if (dyn) {
1752 Dyninfo *dip;
1753 uint_t dynndx;
1754 Xword pltpadsz = 0;
1755 Rti_desc *rti;
1756 Dyn *pdyn;
1757 Word lmtflags = lml->lm_tflags;
1758 int ignore = 0;
1759
1760 /*
1761 * Note, we use DT_NULL to terminate processing, and the
1762 * dynamic entry count as a fall back. Normally, a DT_NULL
1763 * entry marks the end of the dynamic section. Any non-NULL
1764 * items following the first DT_NULL are silently ignored.
1765 * This situation should only occur through use of elfedit(1)
1766 * or a similar tool.
1767 */
1768 for (dynndx = 0, pdyn = NULL, dip = DYNINFO(lmp);
1769 dynndx < dyncnt; dynndx++, pdyn = dyn++, dip++) {
1770
1771 if (ignore) {
1772 dip->di_flags |= FLG_DI_IGNORE;
1773 continue;
1774 }
1775
1776 switch ((Xword)dyn->d_tag) {
1777 case DT_NULL:
1778 dip->di_flags |= ignore = FLG_DI_IGNORE;
1779 break;
1780 case DT_POSFLAG_1:
1781 dip->di_flags |= FLG_DI_POSFLAG1;
1782 break;
1783 case DT_NEEDED:
1784 case DT_USED:
1785 dip->di_flags |= FLG_DI_NEEDED;
1786
1787 /* BEGIN CSTYLED */
1788 if (pdyn && (pdyn->d_tag == DT_POSFLAG_1)) {
1789 /*
1790 * Identify any non-deferred lazy load for
1791 * future processing, unless LD_NOLAZYLOAD
1792 * has been set.
1793 */
1794 if ((pdyn->d_un.d_val & DF_P1_LAZYLOAD) &&
1795 ((lmtflags & LML_TFLG_NOLAZYLD) == 0))
1796 dip->di_flags |= FLG_DI_LAZY;
1797
1798 /*
1799 * Identify any group permission
1800 * requirements.
1801 */
1802 if (pdyn->d_un.d_val & DF_P1_GROUPPERM)
1803 dip->di_flags |= FLG_DI_GROUP;
1804
1805 /*
1806 * Identify any deferred dependencies.
1807 */
1808 if (pdyn->d_un.d_val & DF_P1_DEFERRED)
1809 dip->di_flags |= FLG_DI_DEFERRED;
1810 }
1811 /* END CSTYLED */
1812 break;
1813 case DT_SYMTAB:
1814 SYMTAB(lmp) = (void *)(dyn->d_un.d_ptr + base);
1815 break;
1816 case DT_SUNW_SYMTAB:
1817 SUNWSYMTAB(lmp) =
1818 (void *)(dyn->d_un.d_ptr + base);
1819 break;
1820 case DT_SUNW_SYMSZ:
1821 SUNWSYMSZ(lmp) = dyn->d_un.d_val;
1822 break;
1823 case DT_STRTAB:
1824 STRTAB(lmp) = (void *)(dyn->d_un.d_ptr + base);
1825 break;
1826 case DT_SYMENT:
1827 SYMENT(lmp) = dyn->d_un.d_val;
1828 break;
1829 case DT_FEATURE_1:
1830 if (dyn->d_un.d_val & DTF_1_CONFEXP)
1831 crle = 1;
1832 break;
1833 case DT_MOVESZ:
1834 MOVESZ(lmp) = dyn->d_un.d_val;
1835 FLAGS(lmp) |= FLG_RT_MOVE;
1836 break;
1837 case DT_MOVEENT:
1838 MOVEENT(lmp) = dyn->d_un.d_val;
1839 break;
1840 case DT_MOVETAB:
1841 MOVETAB(lmp) = (void *)(dyn->d_un.d_ptr + base);
1842 break;
1843 case DT_REL:
1844 case DT_RELA:
1845 /*
1846 * At this time, ld.so. can only handle one
1847 * type of relocation per object.
1848 */
1849 REL(lmp) = (void *)(dyn->d_un.d_ptr + base);
1850 break;
1851 case DT_RELSZ:
1852 case DT_RELASZ:
1853 RELSZ(lmp) = dyn->d_un.d_val;
1854 break;
1855 case DT_RELENT:
1856 case DT_RELAENT:
1857 RELENT(lmp) = dyn->d_un.d_val;
1858 break;
1859 case DT_RELCOUNT:
1860 case DT_RELACOUNT:
1861 RELACOUNT(lmp) = (uint_t)dyn->d_un.d_val;
1862 break;
1863 case DT_HASH:
1864 HASH(lmp) = (uint_t *)(dyn->d_un.d_ptr + base);
1865 break;
1866 case DT_PLTGOT:
1867 PLTGOT(lmp) =
1868 (uint_t *)(dyn->d_un.d_ptr + base);
1869 break;
1870 case DT_PLTRELSZ:
1871 PLTRELSZ(lmp) = dyn->d_un.d_val;
1872 break;
1873 case DT_JMPREL:
1874 JMPREL(lmp) = (void *)(dyn->d_un.d_ptr + base);
1875 break;
1876 case DT_INIT:
1877 if (dyn->d_un.d_ptr != NULL)
1878 INIT(lmp) =
1879 (void (*)())(dyn->d_un.d_ptr +
1880 base);
1881 break;
1882 case DT_FINI:
1883 if (dyn->d_un.d_ptr != NULL)
1884 FINI(lmp) =
1885 (void (*)())(dyn->d_un.d_ptr +
1886 base);
1887 break;
1888 case DT_INIT_ARRAY:
1889 INITARRAY(lmp) = (Addr *)(dyn->d_un.d_ptr +
1890 base);
1891 break;
1892 case DT_INIT_ARRAYSZ:
1893 INITARRAYSZ(lmp) = (uint_t)dyn->d_un.d_val;
1894 break;
1895 case DT_FINI_ARRAY:
1896 FINIARRAY(lmp) = (Addr *)(dyn->d_un.d_ptr +
1897 base);
1898 break;
1899 case DT_FINI_ARRAYSZ:
1900 FINIARRAYSZ(lmp) = (uint_t)dyn->d_un.d_val;
1901 break;
1902 case DT_PREINIT_ARRAY:
1903 PREINITARRAY(lmp) = (Addr *)(dyn->d_un.d_ptr +
1904 base);
1905 break;
1906 case DT_PREINIT_ARRAYSZ:
1907 PREINITARRAYSZ(lmp) = (uint_t)dyn->d_un.d_val;
1908 break;
1909 case DT_RPATH:
1910 case DT_RUNPATH:
1911 rpath = dyn->d_un.d_val;
1912 break;
1913 case DT_FILTER:
1914 dip->di_flags |= FLG_DI_STDFLTR;
1915 fltr = dyn->d_un.d_val;
1916 OBJFLTRNDX(lmp) = dynndx;
1917 FLAGS1(lmp) |= FL1_RT_OBJSFLTR;
1918 break;
1919 case DT_AUXILIARY:
1920 dip->di_flags |= FLG_DI_AUXFLTR;
1921 if (!(rtld_flags & RT_FL_NOAUXFLTR)) {
1922 fltr = dyn->d_un.d_val;
1923 OBJFLTRNDX(lmp) = dynndx;
1924 }
1925 FLAGS1(lmp) |= FL1_RT_OBJAFLTR;
1926 break;
1927 case DT_SUNW_FILTER:
1928 dip->di_flags |=
1929 (FLG_DI_STDFLTR | FLG_DI_SYMFLTR);
1930 SYMSFLTRCNT(lmp)++;
1931 FLAGS1(lmp) |= FL1_RT_SYMSFLTR;
1932 break;
1933 case DT_SUNW_AUXILIARY:
1934 dip->di_flags |=
1935 (FLG_DI_AUXFLTR | FLG_DI_SYMFLTR);
1936 if (!(rtld_flags & RT_FL_NOAUXFLTR)) {
1937 SYMAFLTRCNT(lmp)++;
1938 }
1939 FLAGS1(lmp) |= FL1_RT_SYMAFLTR;
1940 break;
1941 case DT_DEPAUDIT:
1942 if (!(rtld_flags & RT_FL_NOAUDIT)) {
1943 audit = dyn->d_un.d_val;
1944 FLAGS1(lmp) |= FL1_RT_DEPAUD;
1945 }
1946 break;
1947 case DT_CONFIG:
1948 cfile = dyn->d_un.d_val;
1949 break;
1950 case DT_DEBUG:
1951 /*
1952 * DT_DEBUG entries are only created in
1953 * dynamic objects that require an interpretor
1954 * (ie. all dynamic executables and some shared
1955 * objects), and provide for a hand-shake with
1956 * old debuggers. This entry is initialized to
1957 * zero by the link-editor. If a debugger is
1958 * monitoring us, and has updated this entry,
1959 * set the debugger monitor flag, and finish
1960 * initializing the debugging structure. See
1961 * setup(). Also, switch off any configuration
1962 * object use as most debuggers can't handle
1963 * fixed dynamic executables as dependencies.
1964 */
1965 if (dyn->d_un.d_ptr)
1966 rtld_flags |=
1967 (RT_FL_DEBUGGER | RT_FL_NOOBJALT);
1968 dyn->d_un.d_ptr = (Addr)&r_debug;
1969 break;
1970 case DT_VERNEED:
1971 VERNEED(lmp) = (Verneed *)(dyn->d_un.d_ptr +
1972 base);
1973 break;
1974 case DT_VERNEEDNUM:
1975 /* LINTED */
1976 VERNEEDNUM(lmp) = (int)dyn->d_un.d_val;
1977 break;
1978 case DT_VERDEF:
1979 VERDEF(lmp) = (Verdef *)(dyn->d_un.d_ptr +
1980 base);
1981 break;
1982 case DT_VERDEFNUM:
1983 /* LINTED */
1984 VERDEFNUM(lmp) = (int)dyn->d_un.d_val;
1985 break;
1986 case DT_VERSYM:
1987 /*
1988 * The Solaris ld does not produce DT_VERSYM,
1989 * but the GNU ld does, in order to support
1990 * their style of versioning, which differs
1991 * from ours in some ways, while using the
1992 * same data structures. The presence of
1993 * DT_VERSYM therefore means that GNU
1994 * versioning rules apply to the given file.
1995 * If DT_VERSYM is not present, then Solaris
1996 * versioning rules apply.
1997 */
1998 VERSYM(lmp) = (Versym *)(dyn->d_un.d_ptr +
1999 base);
2000 break;
2001 case DT_BIND_NOW:
2002 if ((dyn->d_un.d_val & DF_BIND_NOW) &&
2003 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) {
2004 MODE(lmp) |= RTLD_NOW;
2005 MODE(lmp) &= ~RTLD_LAZY;
2006 }
2007 break;
2008 case DT_FLAGS:
2009 FLAGS1(lmp) |= FL1_RT_DTFLAGS;
2010 if (dyn->d_un.d_val & DF_SYMBOLIC)
2011 FLAGS1(lmp) |= FL1_RT_SYMBOLIC;
2012 if ((dyn->d_un.d_val & DF_BIND_NOW) &&
2013 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) {
2014 MODE(lmp) |= RTLD_NOW;
2015 MODE(lmp) &= ~RTLD_LAZY;
2016 }
2017 /*
2018 * Capture any static TLS use, and enforce that
2019 * this object be non-deletable.
2020 */
2021 if (dyn->d_un.d_val & DF_STATIC_TLS) {
2022 FLAGS1(lmp) |= FL1_RT_TLSSTAT;
2023 MODE(lmp) |= RTLD_NODELETE;
2024 }
2025 break;
2026 case DT_FLAGS_1:
2027 if (dyn->d_un.d_val & DF_1_DISPRELPND)
2028 FLAGS1(lmp) |= FL1_RT_DISPREL;
2029 if (dyn->d_un.d_val & DF_1_GROUP)
2030 FLAGS(lmp) |=
2031 (FLG_RT_SETGROUP | FLG_RT_PUBHDL);
2032 if ((dyn->d_un.d_val & DF_1_NOW) &&
2033 ((rtld_flags2 & RT_FL2_BINDLAZY) == 0)) {
2034 MODE(lmp) |= RTLD_NOW;
2035 MODE(lmp) &= ~RTLD_LAZY;
2036 }
2037 if (dyn->d_un.d_val & DF_1_NODELETE)
2038 MODE(lmp) |= RTLD_NODELETE;
2039 if (dyn->d_un.d_val & DF_1_INITFIRST)
2040 FLAGS(lmp) |= FLG_RT_INITFRST;
2041 if (dyn->d_un.d_val & DF_1_NOOPEN)
2042 FLAGS(lmp) |= FLG_RT_NOOPEN;
2043 if (dyn->d_un.d_val & DF_1_LOADFLTR)
2044 FLAGS(lmp) |= FLG_RT_LOADFLTR;
2045 if (dyn->d_un.d_val & DF_1_NODUMP)
2046 FLAGS(lmp) |= FLG_RT_NODUMP;
2047 if (dyn->d_un.d_val & DF_1_CONFALT)
2048 crle = 1;
2049 if (dyn->d_un.d_val & DF_1_DIRECT)
2050 FLAGS1(lmp) |= FL1_RT_DIRECT;
2051 if (dyn->d_un.d_val & DF_1_NODEFLIB)
2052 FLAGS1(lmp) |= FL1_RT_NODEFLIB;
2053 if (dyn->d_un.d_val & DF_1_ENDFILTEE)
2054 FLAGS1(lmp) |= FL1_RT_ENDFILTE;
2055 if (dyn->d_un.d_val & DF_1_TRANS)
2056 FLAGS(lmp) |= FLG_RT_TRANS;
2057
2058 /*
2059 * Global auditing is only meaningful when
2060 * specified by the initiating object of the
2061 * process - typically the dynamic executable.
2062 * If this is the initiating object, its link-
2063 * map will not yet have been added to the
2064 * link-map list, and consequently the link-map
2065 * list is empty. (see setup()).
2066 */
2067 if (dyn->d_un.d_val & DF_1_GLOBAUDIT) {
2068 if (lml_main.lm_head == NULL)
2069 FLAGS1(lmp) |= FL1_RT_GLOBAUD;
2070 else
2071 DBG_CALL(Dbg_audit_ignore(lmp));
2072 }
2073
2074 /*
2075 * If this object identifies itself as an
2076 * interposer, but relocation processing has
2077 * already started, then demote it. It's too
2078 * late to guarantee complete interposition.
2079 */
2080 /* BEGIN CSTYLED */
2081 if (dyn->d_un.d_val &
2082 (DF_1_INTERPOSE | DF_1_SYMINTPOSE)) {
2083 if (lml->lm_flags & LML_FLG_STARTREL) {
2084 DBG_CALL(Dbg_util_intoolate(lmp));
2085 if (lml->lm_flags & LML_FLG_TRC_ENABLE)
2086 (void) printf(
2087 MSG_INTL(MSG_LDD_REL_ERR2),
2088 NAME(lmp));
2089 } else if (dyn->d_un.d_val & DF_1_INTERPOSE)
2090 FLAGS(lmp) |= FLG_RT_OBJINTPO;
2091 else
2092 FLAGS(lmp) |= FLG_RT_SYMINTPO;
2093 }
2094 /* END CSTYLED */
2095 break;
2096 case DT_SYMINFO:
2097 SYMINFO(lmp) = (Syminfo *)(dyn->d_un.d_ptr +
2098 base);
2099 break;
2100 case DT_SYMINENT:
2101 SYMINENT(lmp) = dyn->d_un.d_val;
2102 break;
2103 case DT_PLTPAD:
2104 PLTPAD(lmp) = (void *)(dyn->d_un.d_ptr + base);
2105 break;
2106 case DT_PLTPADSZ:
2107 pltpadsz = dyn->d_un.d_val;
2108 break;
2109 case DT_SUNW_RTLDINF:
2110 /*
2111 * Maintain a list of RTLDINFO structures.
2112 * Typically, libc is the only supplier, and
2113 * only one structure is provided. However,
2114 * multiple suppliers and multiple structures
2115 * are supported. For example, one structure
2116 * may provide thread_init, and another
2117 * structure may provide atexit reservations.
2118 */
2119 if ((rti = alist_append(&lml->lm_rti, NULL,
2120 sizeof (Rti_desc),
2121 AL_CNT_RTLDINFO)) == NULL) {
2122 remove_so(0, lmp, clmp);
2123 return (NULL);
2124 }
2125 rti->rti_lmp = lmp;
2126 rti->rti_info = (void *)(dyn->d_un.d_ptr +
2127 base);
2128 break;
2129 case DT_SUNW_SORTENT:
2130 SUNWSORTENT(lmp) = dyn->d_un.d_val;
2131 break;
2132 case DT_SUNW_SYMSORT:
2133 SUNWSYMSORT(lmp) =
2134 (void *)(dyn->d_un.d_ptr + base);
2135 break;
2136 case DT_SUNW_SYMSORTSZ:
2137 SUNWSYMSORTSZ(lmp) = dyn->d_un.d_val;
2138 break;
2139 case DT_DEPRECATED_SPARC_REGISTER:
2140 case M_DT_REGISTER:
2141 dip->di_flags |= FLG_DI_REGISTER;
2142 FLAGS(lmp) |= FLG_RT_REGSYMS;
2143 break;
2144 case DT_SUNW_CAP:
2145 CAP(lmp) = (void *)(dyn->d_un.d_ptr + base);
2146 break;
2147 case DT_SUNW_CAPINFO:
2148 CAPINFO(lmp) = (void *)(dyn->d_un.d_ptr + base);
2149 break;
2150 case DT_SUNW_CAPCHAIN:
2151 CAPCHAIN(lmp) = (void *)(dyn->d_un.d_ptr +
2152 base);
2153 break;
2154 case DT_SUNW_CAPCHAINENT:
2155 CAPCHAINENT(lmp) = dyn->d_un.d_val;
2156 break;
2157 case DT_SUNW_CAPCHAINSZ:
2158 CAPCHAINSZ(lmp) = dyn->d_un.d_val;
2159 break;
2160 }
2161 }
2162
2163 /*
2164 * Update any Dyninfo string pointers now that STRTAB() is
2165 * known.
2166 */
2167 for (dynndx = 0, dyn = DYN(lmp), dip = DYNINFO(lmp);
2168 !(dip->di_flags & FLG_DI_IGNORE); dyn++, dip++) {
2169
2170 switch ((Xword)dyn->d_tag) {
2171 case DT_NEEDED:
2172 case DT_USED:
2173 case DT_FILTER:
2174 case DT_AUXILIARY:
2175 case DT_SUNW_FILTER:
2176 case DT_SUNW_AUXILIARY:
2177 dip->di_name = STRTAB(lmp) + dyn->d_un.d_val;
2178 break;
2179 }
2180 }
2181
2182 /*
2183 * Assign any padding.
2184 */
2185 if (PLTPAD(lmp)) {
2186 if (pltpadsz == (Xword)0)
2187 PLTPAD(lmp) = NULL;
2188 else
2189 PLTPADEND(lmp) = (void *)((Addr)PLTPAD(lmp) +
2190 pltpadsz);
2191 }
2192 }
2193
2194 /*
2195 * A dynsym contains only global functions. We want to have
2196 * a version of it that also includes local functions, so that
2197 * dladdr() will be able to report names for local functions
2198 * when used to generate a stack trace for a stripped file.
2199 * This version of the dynsym is provided via DT_SUNW_SYMTAB.
2200 *
2201 * In producing DT_SUNW_SYMTAB, ld uses a non-obvious trick
2202 * in order to avoid having to have two copies of the global
2203 * symbols held in DT_SYMTAB: The local symbols are placed in
2204 * a separate section than the globals in the dynsym, but the
2205 * linker conspires to put the data for these two sections adjacent
2206 * to each other. DT_SUNW_SYMTAB points at the top of the local
2207 * symbols, and DT_SUNW_SYMSZ is the combined length of both tables.
2208 *
2209 * If the two sections are not adjacent, then something went wrong
2210 * at link time. We use ASSERT to kill the process if this is
2211 * a debug build. In a production build, we will silently ignore
2212 * the presence of the .ldynsym and proceed. We can detect this
2213 * situation by checking to see that DT_SYMTAB lies in
2214 * the range given by DT_SUNW_SYMTAB/DT_SUNW_SYMSZ.
2215 */
2216 if ((SUNWSYMTAB(lmp) != NULL) &&
2217 (((char *)SYMTAB(lmp) <= (char *)SUNWSYMTAB(lmp)) ||
2218 (((char *)SYMTAB(lmp) >=
2219 (SUNWSYMSZ(lmp) + (char *)SUNWSYMTAB(lmp)))))) {
2220 ASSERT(0);
2221 SUNWSYMTAB(lmp) = NULL;
2222 SUNWSYMSZ(lmp) = 0;
2223 }
2224
2225 /*
2226 * If configuration file use hasn't been disabled, and a configuration
2227 * file hasn't already been set via an environment variable, see if any
2228 * application specific configuration file is specified. An LD_CONFIG
2229 * setting is used first, but if this image was generated via crle(1)
2230 * then a default configuration file is a fall-back.
2231 */
2232 if ((!(rtld_flags & RT_FL_NOCFG)) && (config->c_name == NULL)) {
2233 if (cfile)
2234 config->c_name = (const char *)(cfile +
2235 (char *)STRTAB(lmp));
2236 else if (crle)
2237 rtld_flags |= RT_FL_CONFAPP;
2238 }
2239
2240 if (rpath)
2241 RPATH(lmp) = (char *)(rpath + (char *)STRTAB(lmp));
2242 if (fltr)
2243 REFNAME(lmp) = (char *)(fltr + (char *)STRTAB(lmp));
2244
2245 /*
2246 * For Intel ABI compatibility. It's possible that a JMPREL can be
2247 * specified without any other relocations (e.g. a dynamic executable
2248 * normally only contains .plt relocations). If this is the case then
2249 * no REL, RELSZ or RELENT will have been created. For us to be able
2250 * to traverse the .plt relocations under LD_BIND_NOW we need to know
2251 * the RELENT for these relocations. Refer to elf_reloc() for more
2252 * details.
2253 */
2254 if (!RELENT(lmp) && JMPREL(lmp))
2255 RELENT(lmp) = sizeof (M_RELOC);
2256
2257 /*
2258 * Establish any per-object auditing. If we're establishing main's
2259 * link-map its too early to go searching for audit objects so just
2260 * hold the object name for later (see setup()).
2261 */
2262 if (audit) {
2263 char *cp = audit + (char *)STRTAB(lmp);
2264
2265 if (*cp) {
2266 if (((AUDITORS(lmp) =
2267 calloc(1, sizeof (Audit_desc))) == NULL) ||
2268 ((AUDITORS(lmp)->ad_name = strdup(cp)) == NULL)) {
2269 remove_so(0, lmp, clmp);
2270 return (NULL);
2271 }
2272 if (lml_main.lm_head) {
2273 if (audit_setup(lmp, AUDITORS(lmp), 0,
2274 in_nfavl) == 0) {
2275 remove_so(0, lmp, clmp);
2276 return (NULL);
2277 }
2278 AFLAGS(lmp) |= AUDITORS(lmp)->ad_flags;
2279 lml->lm_flags |= LML_FLG_LOCAUDIT;
2280 }
2281 }
2282 }
2283
2284 if (tphdr && (tls_assign(lml, lmp, tphdr) == 0)) {
2285 remove_so(0, lmp, clmp);
2286 return (NULL);
2287 }
2288
2289 /*
2290 * A capabilities section should be identified by a DT_SUNW_CAP entry,
2291 * and if non-empty object capabilities are included, a PT_SUNWCAP
2292 * header should reference the section. Make sure CAP() is set
2293 * regardless.
2294 */
2295 if ((CAP(lmp) == NULL) && cap)
2296 CAP(lmp) = cap;
2297
2298 /*
2299 * Make sure any capabilities information or chain can be handled.
2300 */
2301 if (CAPINFO(lmp) && (CAPINFO(lmp)[0] > CAPINFO_CURRENT))
2302 CAPINFO(lmp) = NULL;
2303 if (CAPCHAIN(lmp) && (CAPCHAIN(lmp)[0] > CAPCHAIN_CURRENT))
2304 CAPCHAIN(lmp) = NULL;
2305
2306 /*
2307 * As part of processing dependencies, a file descriptor is populated
2308 * with capabilities information following validation.
2309 */
2310 if (fdp->fd_flags & FLG_FD_ALTCHECK) {
2311 FLAGS1(lmp) |= FL1_RT_ALTCHECK;
2312 CAPSET(lmp) = fdp->fd_scapset;
2313
2314 if (fdp->fd_flags & FLG_FD_ALTCAP)
2315 FLAGS1(lmp) |= FL1_RT_ALTCAP;
2316
2317 } else if ((cap = CAP(lmp)) != NULL) {
2318 /*
2319 * Processing of the a.out and ld.so.1 does not involve a file
2320 * descriptor as exec() did all the work, so capture the
2321 * capabilities for these cases.
2322 */
2323 while (cap->c_tag != CA_SUNW_NULL) {
2324 switch (cap->c_tag) {
2325 case CA_SUNW_HW_1:
2326 CAPSET(lmp).sc_hw_1 = cap->c_un.c_val;
2327 break;
2328 case CA_SUNW_SF_1:
2329 CAPSET(lmp).sc_sf_1 = cap->c_un.c_val;
2330 break;
2331 case CA_SUNW_HW_2:
2332 CAPSET(lmp).sc_hw_2 = cap->c_un.c_val;
2333 break;
2334 case CA_SUNW_PLAT:
2335 CAPSET(lmp).sc_plat = STRTAB(lmp) +
2336 cap->c_un.c_ptr;
2337 break;
2338 case CA_SUNW_MACH:
2339 CAPSET(lmp).sc_mach = STRTAB(lmp) +
2340 cap->c_un.c_ptr;
2341 break;
2342 }
2343 cap++;
2344 }
2345 }
2346
2347 /*
2348 * If a capabilities chain table exists, duplicate it. The chain table
2349 * is inspected for each initial call to a capabilities family lead
2350 * symbol. From this chain, each family member is inspected to
2351 * determine the 'best' family member. The chain table is then updated
2352 * so that the best member is immediately selected for any further
2353 * family searches.
2354 */
2355 if (CAPCHAIN(lmp)) {
2356 Capchain *capchain;
2357
2358 if ((capchain = calloc(CAPCHAINSZ(lmp), 1)) == NULL)
2359 return (NULL);
2360 (void) memcpy(capchain, CAPCHAIN(lmp), CAPCHAINSZ(lmp));
2361 CAPCHAIN(lmp) = capchain;
2362 }
2363
2364 /*
2365 * Add the mapped object to the end of the link map list.
2366 */
2367 lm_append(lml, lmco, lmp);
2368
2369 /*
2370 * Start the system loading in the ELF information we'll be processing.
2371 */
2372 if (REL(lmp)) {
2373 (void) madvise((void *)ADDR(lmp), (uintptr_t)REL(lmp) +
2374 (uintptr_t)RELSZ(lmp) - (uintptr_t)ADDR(lmp),
2375 MADV_WILLNEED);
2376 }
2377 return (lmp);
2378 }
2379
2380 /*
2381 * Build full pathname of shared object from given directory name and filename.
2382 */
2383 static char *
2384 elf_get_so(const char *dir, const char *file, size_t dlen, size_t flen)
2385 {
2386 static char pname[PATH_MAX];
2387
2388 (void) strncpy(pname, dir, dlen);
2389 pname[dlen++] = '/';
2390 (void) strncpy(&pname[dlen], file, flen + 1);
2391 return (pname);
2392 }
2393
2394 /*
2395 * The copy relocation is recorded in a copy structure which will be applied
2396 * after all other relocations are carried out. This provides for copying data
2397 * that must be relocated itself (ie. pointers in shared objects). This
2398 * structure also provides a means of binding RTLD_GROUP dependencies to any
2399 * copy relocations that have been taken from any group members.
2400 *
2401 * If the size of the .bss area available for the copy information is not the
2402 * same as the source of the data inform the user if we're under ldd(1) control
2403 * (this checking was only established in 5.3, so by only issuing an error via
2404 * ldd(1) we maintain the standard set by previous releases).
2405 */
2406 int
2407 elf_copy_reloc(char *name, Sym *rsym, Rt_map *rlmp, void *radd, Sym *dsym,
2408 Rt_map *dlmp, const void *dadd)
2409 {
2410 Rel_copy rc;
2411 Lm_list *lml = LIST(rlmp);
2412
2413 rc.r_name = name;
2414 rc.r_rsym = rsym; /* the new reference symbol and its */
2415 rc.r_rlmp = rlmp; /* associated link-map */
2416 rc.r_dlmp = dlmp; /* the defining link-map */
2417 rc.r_dsym = dsym; /* the original definition */
2418 rc.r_radd = radd;
2419 rc.r_dadd = dadd;
2420
2421 if (rsym->st_size > dsym->st_size)
2422 rc.r_size = (size_t)dsym->st_size;
2423 else
2424 rc.r_size = (size_t)rsym->st_size;
2425
2426 if (alist_append(©_R(dlmp), &rc, sizeof (Rel_copy),
2427 AL_CNT_COPYREL) == NULL) {
2428 if (!(lml->lm_flags & LML_FLG_TRC_WARN))
2429 return (0);
2430 else
2431 return (1);
2432 }
2433 if (!(FLAGS1(dlmp) & FL1_RT_COPYTOOK)) {
2434 if (aplist_append(©_S(rlmp), dlmp,
2435 AL_CNT_COPYREL) == NULL) {
2436 if (!(lml->lm_flags & LML_FLG_TRC_WARN))
2437 return (0);
2438 else
2439 return (1);
2440 }
2441 FLAGS1(dlmp) |= FL1_RT_COPYTOOK;
2442 }
2443
2444 /*
2445 * If we are tracing (ldd), warn the user if
2446 * 1) the size from the reference symbol differs from the
2447 * copy definition. We can only copy as much data as the
2448 * reference (dynamic executables) entry allows.
2449 * 2) the copy definition has STV_PROTECTED visibility.
2450 */
2451 if (lml->lm_flags & LML_FLG_TRC_WARN) {
2452 if (rsym->st_size != dsym->st_size) {
2453 (void) printf(MSG_INTL(MSG_LDD_CPY_SIZDIF),
2454 _conv_reloc_type(M_R_COPY), demangle(name),
2455 NAME(rlmp), EC_XWORD(rsym->st_size),
2456 NAME(dlmp), EC_XWORD(dsym->st_size));
2457 if (rsym->st_size > dsym->st_size)
2458 (void) printf(MSG_INTL(MSG_LDD_CPY_INSDATA),
2459 NAME(dlmp));
2460 else
2461 (void) printf(MSG_INTL(MSG_LDD_CPY_DATRUNC),
2462 NAME(rlmp));
2463 }
2464
2465 if (ELF_ST_VISIBILITY(dsym->st_other) == STV_PROTECTED) {
2466 (void) printf(MSG_INTL(MSG_LDD_CPY_PROT),
2467 _conv_reloc_type(M_R_COPY), demangle(name),
2468 NAME(dlmp));
2469 }
2470 }
2471
2472 DBG_CALL(Dbg_reloc_apply_val(lml, ELF_DBG_RTLD, (Xword)radd,
2473 (Xword)rc.r_size));
2474 return (1);
2475 }
2476
2477 /*
2478 * Determine the symbol location of an address within a link-map. Look for
2479 * the nearest symbol (whose value is less than or equal to the required
2480 * address). This is the object specific part of dladdr().
2481 */
2482 static void
2483 elf_dladdr(ulong_t addr, Rt_map *lmp, Dl_info *dlip, void **info, int flags)
2484 {
2485 ulong_t ndx, cnt, base, _value;
2486 Sym *sym, *_sym = NULL;
2487 const char *str;
2488 int _flags;
2489 uint_t *dynaddr_ndx;
2490 uint_t dynaddr_n = 0;
2491 ulong_t value;
2492
2493 /*
2494 * If SUNWSYMTAB() is non-NULL, then it sees a special version of
2495 * the dynsym that starts with any local function symbols that exist in
2496 * the library and then moves to the data held in SYMTAB(). In this
2497 * case, SUNWSYMSZ tells us how long the symbol table is. The
2498 * availability of local function symbols will enhance the results
2499 * we can provide.
2500 *
2501 * If SUNWSYMTAB() is non-NULL, then there might also be a
2502 * SUNWSYMSORT() vector associated with it. SUNWSYMSORT() contains
2503 * an array of indices into SUNWSYMTAB, sorted by increasing
2504 * address. We can use this to do an O(log N) search instead of a
2505 * brute force search.
2506 *
2507 * If SUNWSYMTAB() is NULL, then SYMTAB() references a dynsym that
2508 * contains only global symbols. In that case, the length of
2509 * the symbol table comes from the nchain field of the related
2510 * symbol lookup hash table.
2511 */
2512 str = STRTAB(lmp);
2513 if (SUNWSYMSZ(lmp) == NULL) {
2514 sym = SYMTAB(lmp);
2515 /*
2516 * If we don't have a .hash table there are no symbols
2517 * to look at.
2518 */
2519 if (HASH(lmp) == NULL)
2520 return;
2521 cnt = HASH(lmp)[1];
2522 } else {
2523 sym = SUNWSYMTAB(lmp);
2524 cnt = SUNWSYMSZ(lmp) / SYMENT(lmp);
2525 dynaddr_ndx = SUNWSYMSORT(lmp);
2526 if (dynaddr_ndx != NULL)
2527 dynaddr_n = SUNWSYMSORTSZ(lmp) / SUNWSORTENT(lmp);
2528 }
2529
2530 if (FLAGS(lmp) & FLG_RT_FIXED)
2531 base = 0;
2532 else
2533 base = ADDR(lmp);
2534
2535 if (dynaddr_n > 0) { /* Binary search */
2536 long low = 0, low_bnd;
2537 long high = dynaddr_n - 1, high_bnd;
2538 long mid;
2539 Sym *mid_sym;
2540
2541 /*
2542 * Note that SUNWSYMSORT only contains symbols types that
2543 * supply memory addresses, so there's no need to check and
2544 * filter out any other types.
2545 */
2546 low_bnd = low;
2547 high_bnd = high;
2548 while (low <= high) {
2549 mid = (low + high) / 2;
2550 mid_sym = &sym[dynaddr_ndx[mid]];
2551 value = mid_sym->st_value + base;
2552 if (addr < value) {
2553 if ((sym[dynaddr_ndx[high]].st_value + base) >=
2554 addr)
2555 high_bnd = high;
2556 high = mid - 1;
2557 } else if (addr > value) {
2558 if ((sym[dynaddr_ndx[low]].st_value + base) <=
2559 addr)
2560 low_bnd = low;
2561 low = mid + 1;
2562 } else {
2563 _sym = mid_sym;
2564 _value = value;
2565 break;
2566 }
2567 }
2568 /*
2569 * If the above didn't find it exactly, then we must
2570 * return the closest symbol with a value that doesn't
2571 * exceed the one we are looking for. If that symbol exists,
2572 * it will lie in the range bounded by low_bnd and
2573 * high_bnd. This is a linear search, but a short one.
2574 */
2575 if (_sym == NULL) {
2576 for (mid = low_bnd; mid <= high_bnd; mid++) {
2577 mid_sym = &sym[dynaddr_ndx[mid]];
2578 value = mid_sym->st_value + base;
2579 if (addr >= value) {
2580 _sym = mid_sym;
2581 _value = value;
2582 } else {
2583 break;
2584 }
2585 }
2586 }
2587 } else { /* Linear search */
2588 for (_value = 0, sym++, ndx = 1; ndx < cnt; ndx++, sym++) {
2589 /*
2590 * Skip expected symbol types that are not functions
2591 * or data:
2592 * - A symbol table starts with an undefined symbol
2593 * in slot 0. If we are using SUNWSYMTAB(),
2594 * there will be a second undefined symbol
2595 * right before the globals.
2596 * - The local part of SUNWSYMTAB() contains a
2597 * series of function symbols. Each section
2598 * starts with an initial STT_FILE symbol.
2599 */
2600 if ((sym->st_shndx == SHN_UNDEF) ||
2601 (ELF_ST_TYPE(sym->st_info) == STT_FILE))
2602 continue;
2603
2604 value = sym->st_value + base;
2605 if (value > addr)
2606 continue;
2607 if (value < _value)
2608 continue;
2609
2610 _sym = sym;
2611 _value = value;
2612
2613 /*
2614 * Note, because we accept local and global symbols
2615 * we could find a section symbol that matches the
2616 * associated address, which means that the symbol
2617 * name will be null. In this case continue the
2618 * search in case we can find a global symbol of
2619 * the same value.
2620 */
2621 if ((value == addr) &&
2622 (ELF_ST_TYPE(sym->st_info) != STT_SECTION))
2623 break;
2624 }
2625 }
2626
2627 _flags = flags & RTLD_DL_MASK;
2628 if (_sym) {
2629 if (_flags == RTLD_DL_SYMENT)
2630 *info = (void *)_sym;
2631 else if (_flags == RTLD_DL_LINKMAP)
2632 *info = (void *)lmp;
2633
2634 dlip->dli_sname = str + _sym->st_name;
2635 dlip->dli_saddr = (void *)_value;
2636 } else {
2637 /*
2638 * addr lies between the beginning of the mapped segment and
2639 * the first global symbol. We have no symbol to return
2640 * and the caller requires one. We use _START_, the base
2641 * address of the mapping.
2642 */
2643
2644 if (_flags == RTLD_DL_SYMENT) {
2645 /*
2646 * An actual symbol struct is needed, so we
2647 * construct one for _START_. To do this in a
2648 * fully accurate way requires a different symbol
2649 * for each mapped segment. This requires the
2650 * use of dynamic memory and a mutex. That's too much
2651 * plumbing for a fringe case of limited importance.
2652 *
2653 * Fortunately, we can simplify:
2654 * - Only the st_size and st_info fields are useful
2655 * outside of the linker internals. The others
2656 * reference things that outside code cannot see,
2657 * and can be set to 0.
2658 * - It's just a label and there is no size
2659 * to report. So, the size should be 0.
2660 * This means that only st_info needs a non-zero
2661 * (constant) value. A static struct will suffice.
2662 * It must be const (readonly) so the caller can't
2663 * change its meaning for subsequent callers.
2664 */
2665 static const Sym fsym = { 0, 0, 0,
2666 ELF_ST_INFO(STB_LOCAL, STT_OBJECT) };
2667 *info = (void *) &fsym;
2668 }
2669
2670 dlip->dli_sname = MSG_ORIG(MSG_SYM_START);
2671 dlip->dli_saddr = (void *) ADDR(lmp);
2672 }
2673 }
2674
2675 /*
2676 * This routine is called as a last fall-back to search for a symbol from a
2677 * standard relocation or dlsym(). To maintain lazy loadings goal of reducing
2678 * the number of objects mapped, any symbol search is first carried out using
2679 * the objects that already exist in the process (either on a link-map list or
2680 * handle). If a symbol can't be found, and lazy dependencies are still
2681 * pending, this routine loads the dependencies in an attempt to locate the
2682 * symbol.
2683 */
2684 int
2685 elf_lazy_find_sym(Slookup *slp, Sresult *srp, uint_t *binfo, int *in_nfavl)
2686 {
2687 static APlist *alist = NULL;
2688 Aliste idx1;
2689 Rt_map *lmp1, *lmp = slp->sl_imap, *clmp = slp->sl_cmap;
2690 const char *name = slp->sl_name;
2691 Slookup sl1 = *slp;
2692 Lm_list *lml;
2693 Lm_cntl *lmc;
2694
2695 /*
2696 * It's quite possible we've been here before to process objects,
2697 * therefore reinitialize our dynamic list.
2698 */
2699 if (alist)
2700 aplist_reset(alist);
2701
2702 /*
2703 * Discard any relocation index from further symbol searches. This
2704 * index has already been used to trigger any necessary lazy-loads,
2705 * and it might be because one of these lazy loads has failed that
2706 * we're performing this fallback. By removing the relocation index
2707 * we don't try and perform the same failed lazy loading activity again.
2708 */
2709 sl1.sl_rsymndx = 0;
2710
2711 /*
2712 * Determine the callers link-map list so that we can monitor whether
2713 * new objects have been added.
2714 */
2715 lml = LIST(clmp);
2716 lmc = (Lm_cntl *)alist_item_by_offset(lml->lm_lists, CNTL(clmp));
2717
2718 /*
2719 * Generate a local list of new objects to process. This list can grow
2720 * as each object supplies its own lazy dependencies.
2721 */
2722 if (aplist_append(&alist, lmp, AL_CNT_LAZYFIND) == NULL)
2723 return (NULL);
2724
2725 for (APLIST_TRAVERSE(alist, idx1, lmp1)) {
2726 uint_t dynndx;
2727 Dyninfo *dip, *pdip;
2728
2729 /*
2730 * Loop through the lazy DT_NEEDED entries examining each object
2731 * for the required symbol. If the symbol is not found, the
2732 * object is in turn added to the local alist, so that the
2733 * objects lazy DT_NEEDED entries can be examined.
2734 */
2735 lmp = lmp1;
2736 for (dynndx = 0, dip = DYNINFO(lmp), pdip = NULL;
2737 !(dip->di_flags & FLG_DI_IGNORE); dynndx++, pdip = dip++) {
2738 Grp_hdl *ghp;
2739 Grp_desc *gdp;
2740 Rt_map *nlmp, *llmp;
2741 Slookup sl2;
2742 Sresult sr;
2743 Aliste idx2;
2744
2745 if (((dip->di_flags & FLG_DI_LAZY) == 0) ||
2746 dip->di_info)
2747 continue;
2748
2749 /*
2750 * If this object has already failed to lazy load, and
2751 * we're still processing the same runtime linker
2752 * operation that produced the failure, don't bother
2753 * to try and load the object again.
2754 */
2755 if ((dip->di_flags & FLG_DI_LAZYFAIL) && pdip &&
2756 (pdip->di_flags & FLG_DI_POSFLAG1)) {
2757 if (pdip->di_info == (void *)ld_entry_cnt)
2758 continue;
2759
2760 dip->di_flags &= ~FLG_DI_LAZYFAIL;
2761 pdip->di_info = NULL;
2762 }
2763
2764 /*
2765 * Determine the last link-map presently on the callers
2766 * link-map control list.
2767 */
2768 llmp = lmc->lc_tail;
2769
2770 /*
2771 * Try loading this lazy dependency. If the object
2772 * can't be loaded, consider this non-fatal and continue
2773 * the search. Lazy loaded dependencies need not exist
2774 * and their loading should only turn out to be fatal
2775 * if they are required to satisfy a relocation.
2776 *
2777 * A successful lazy load can mean one of two things:
2778 *
2779 * - new objects have been loaded, in which case the
2780 * objects will have been analyzed, relocated, and
2781 * finally moved to the callers control list.
2782 * - the objects are already loaded, and this lazy
2783 * load has simply associated the referenced object
2784 * with it's lazy dependencies.
2785 *
2786 * If new objects are loaded, look in these objects
2787 * first. Note, a new object can be the object being
2788 * referenced by this lazy load, however we can also
2789 * descend into multiple lazy loads as we relocate this
2790 * reference.
2791 *
2792 * If the symbol hasn't been found, use the referenced
2793 * objects handle, as it might have dependencies on
2794 * objects that are already loaded. Note that existing
2795 * objects might have already been searched and skipped
2796 * as non-available to this caller. However, a lazy
2797 * load might have caused the promotion of modes, or
2798 * added this object to the family of the caller. In
2799 * either case, the handle associated with the object
2800 * is then used to carry out the symbol search.
2801 */
2802 if ((nlmp = elf_lazy_load(lmp, &sl1, dynndx, name,
2803 FLG_RT_PRIHDL, &ghp, in_nfavl)) == NULL)
2804 continue;
2805
2806 if (NEXT_RT_MAP(llmp)) {
2807 /*
2808 * Look in any new objects.
2809 */
2810 sl1.sl_imap = NEXT_RT_MAP(llmp);
2811 sl1.sl_flags &= ~LKUP_STDRELOC;
2812
2813 /*
2814 * Initialize a local symbol result descriptor,
2815 * using the original symbol name.
2816 */
2817 SRESULT_INIT(sr, slp->sl_name);
2818
2819 if (lookup_sym(&sl1, &sr, binfo, in_nfavl)) {
2820 *srp = sr;
2821 return (1);
2822 }
2823 }
2824
2825 /*
2826 * Use the objects handle to inspect the family of
2827 * objects associated with the handle. Note, there's
2828 * a possibility of overlap with the above search,
2829 * should a lazy load bring in new objects and
2830 * reference existing objects.
2831 */
2832 sl2 = sl1;
2833 for (ALIST_TRAVERSE(ghp->gh_depends, idx2, gdp)) {
2834 if ((gdp->gd_depend != NEXT_RT_MAP(llmp)) &&
2835 (gdp->gd_flags & GPD_DLSYM)) {
2836
2837 sl2.sl_imap = gdp->gd_depend;
2838 sl2.sl_flags |= LKUP_FIRST;
2839
2840 /*
2841 * Initialize a local symbol result
2842 * descriptor, using the original
2843 * symbol name.
2844 */
2845 SRESULT_INIT(sr, slp->sl_name);
2846
2847 if (lookup_sym(&sl2, &sr, binfo,
2848 in_nfavl)) {
2849 *srp = sr;
2850 return (1);
2851 }
2852 }
2853 }
2854
2855 /*
2856 * Some dlsym() operations are already traversing a
2857 * link-map (dlopen(0)), and thus there's no need to
2858 * save them on the dynamic dependency list.
2859 */
2860 if (slp->sl_flags & LKUP_NODESCENT)
2861 continue;
2862
2863 if (aplist_test(&alist, nlmp, AL_CNT_LAZYFIND) == NULL)
2864 return (0);
2865 }
2866 }
2867
2868 return (0);
2869 }
2870
2871 /*
2872 * Warning message for bad r_offset.
2873 */
2874 void
2875 elf_reloc_bad(Rt_map *lmp, void *rel, uchar_t rtype, ulong_t roffset,
2876 ulong_t rsymndx)
2877 {
2878 const char *name = NULL;
2879 Lm_list *lml = LIST(lmp);
2880 int trace;
2881
2882 if ((lml->lm_flags & LML_FLG_TRC_ENABLE) &&
2883 (((rtld_flags & RT_FL_SILENCERR) == 0) ||
2884 (lml->lm_flags & LML_FLG_TRC_VERBOSE)))
2885 trace = 1;
2886 else
2887 trace = 0;
2888
2889 if ((trace == 0) && (DBG_ENABLED == 0))
2890 return;
2891
2892 if (rsymndx) {
2893 Sym *symref = (Sym *)((ulong_t)SYMTAB(lmp) +
2894 (rsymndx * SYMENT(lmp)));
2895
2896 if (ELF_ST_BIND(symref->st_info) != STB_LOCAL)
2897 name = (char *)(STRTAB(lmp) + symref->st_name);
2898 }
2899
2900 if (name == NULL)
2901 name = MSG_INTL(MSG_STR_UNKNOWN);
2902
2903 if (trace) {
2904 const char *rstr;
2905
2906 rstr = _conv_reloc_type((uint_t)rtype);
2907 (void) printf(MSG_INTL(MSG_LDD_REL_ERR1), rstr, name,
2908 EC_ADDR(roffset));
2909 return;
2910 }
2911
2912 Dbg_reloc_error(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel, name);
2913 }
2914
2915 /*
2916 * Resolve a static TLS relocation.
2917 */
2918 long
2919 elf_static_tls(Rt_map *lmp, Sym *sym, void *rel, uchar_t rtype, char *name,
2920 ulong_t roffset, long value)
2921 {
2922 Lm_list *lml = LIST(lmp);
2923
2924 /*
2925 * Relocations against a static TLS block have limited support once
2926 * process initialization has completed. Any error condition should be
2927 * discovered by testing for DF_STATIC_TLS as part of loading an object,
2928 * however individual relocations are tested in case the dynamic flag
2929 * had not been set when this object was built.
2930 */
2931 if (PTTLS(lmp) == NULL) {
2932 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH,
2933 M_REL_SHT_TYPE, rel, NULL, 0, name));
2934 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS),
2935 _conv_reloc_type((uint_t)rtype), NAME(lmp),
2936 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN));
2937 return (0);
2938 }
2939
2940 /*
2941 * If no static TLS has been set aside for this object, determine if
2942 * any can be obtained. Enforce that any object using static TLS is
2943 * non-deletable.
2944 */
2945 if (TLSSTATOFF(lmp) == 0) {
2946 FLAGS1(lmp) |= FL1_RT_TLSSTAT;
2947 MODE(lmp) |= RTLD_NODELETE;
2948
2949 if (tls_assign(lml, lmp, PTTLS(lmp)) == 0) {
2950 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH,
2951 M_REL_SHT_TYPE, rel, NULL, 0, name));
2952 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_BADTLS),
2953 _conv_reloc_type((uint_t)rtype), NAME(lmp),
2954 name ? demangle(name) : MSG_INTL(MSG_STR_UNKNOWN));
2955 return (0);
2956 }
2957 }
2958
2959 /*
2960 * Typically, a static TLS offset is maintained as a symbols value.
2961 * For local symbols that are not apart of the dynamic symbol table,
2962 * the TLS relocation points to a section symbol, and the static TLS
2963 * offset was deposited in the associated GOT table. Make sure the GOT
2964 * is cleared, so that the value isn't reused in do_reloc().
2965 */
2966 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
2967 if ((ELF_ST_TYPE(sym->st_info) == STT_SECTION)) {
2968 value = *(long *)roffset;
2969 *(long *)roffset = 0;
2970 } else {
2971 value = sym->st_value;
2972 }
2973 }
2974 return (-(TLSSTATOFF(lmp) - value));
2975 }
2976
2977 /*
2978 * If the symbol is not found and the reference was not to a weak symbol, report
2979 * an error. Weak references may be unresolved.
2980 */
2981 int
2982 elf_reloc_error(Rt_map *lmp, const char *name, void *rel, uint_t binfo)
2983 {
2984 Lm_list *lml = LIST(lmp);
2985
2986 /*
2987 * Under crle(1), relocation failures are ignored.
2988 */
2989 if (lml->lm_flags & LML_FLG_IGNRELERR)
2990 return (1);
2991
2992 /*
2993 * Under ldd(1), unresolved references are reported. However, if the
2994 * original reference is EXTERN or PARENT these references are ignored
2995 * unless ldd's -p option is in effect.
2996 */
2997 if (lml->lm_flags & LML_FLG_TRC_WARN) {
2998 if (((binfo & DBG_BINFO_REF_MSK) == 0) ||
2999 ((lml->lm_flags & LML_FLG_TRC_NOPAREXT) != 0)) {
3000 (void) printf(MSG_INTL(MSG_LDD_SYM_NFOUND),
3001 demangle(name), NAME(lmp));
3002 }
3003 return (1);
3004 }
3005
3006 /*
3007 * Otherwise, the unresolved references is fatal.
3008 */
3009 DBG_CALL(Dbg_reloc_in(lml, ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE, rel,
3010 NULL, 0, name));
3011 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
3012 demangle(name));
3013
3014 return (0);
3015 }