xref: /illumos-gate/usr/src/cmd/sgs/libld/common/version.c (revision 46e5ca4c180bbc8cb48be79bc045e873add461ac)
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 #include	<string.h>
28 #include	<stdio.h>
29 #include	<debug.h>
30 #include	"msg.h"
31 #include	"_libld.h"
32 
33 /*
34  * Locate a version descriptor.
35  */
36 Ver_desc *
37 ld_vers_find(const char *name, Word hash, APlist *alp)
38 {
39 	Aliste		idx;
40 	Ver_desc	*vdp;
41 
42 	for (APLIST_TRAVERSE(alp, idx, vdp)) {
43 		if (vdp->vd_hash != hash)
44 			continue;
45 		if (strcmp(vdp->vd_name, name) == 0)
46 			return (vdp);
47 	}
48 	return (NULL);
49 }
50 
51 /*
52  * Add a new version descriptor to a version descriptor list.  Note, users of
53  * this are responsible for determining if the version descriptor already
54  * exists (this can reduce the need to allocate storage for descriptor names
55  * until it is determined a descriptor need be created (see map_symbol())).
56  */
57 Ver_desc *
58 ld_vers_desc(const char *name, Word hash, APlist **alpp)
59 {
60 	Ver_desc	*vdp;
61 
62 	if ((vdp = libld_calloc(sizeof (Ver_desc), 1)) == NULL)
63 		return ((Ver_desc *)S_ERROR);
64 
65 	vdp->vd_name = name;
66 	vdp->vd_hash = hash;
67 
68 	if (aplist_append(alpp, vdp, AL_CNT_VERDESCS) == NULL)
69 		return ((Ver_desc *)S_ERROR);
70 
71 	return (vdp);
72 }
73 
74 /*
75  * Now that all explict files have been processed validate any version
76  * definitions.  Insure that any version references are available (a version
77  * has been defined when it's been assigned an index).  Also calculate the
78  * number of .version section entries that will be required to hold this
79  * information.
80  */
81 #define	_NUM_OF_VERS_	40	/* twice as big as the depth for libc version */
82 typedef struct {
83 	Ver_desc	**ver_stk;
84 	int 		ver_sp;
85 	int 		ver_lmt;
86 } Ver_Stack;
87 
88 static uintptr_t
89 vers_visit_children(Ofl_desc *ofl, Ver_desc *vp, int flag)
90 {
91 	Aliste			idx;
92 	Ver_desc		*vdp;
93 	static int		err = 0;
94 	static Ver_Stack	ver_stk = {0, 0, 0};
95 	int			tmp_sp;
96 
97 	/*
98 	 * If there was any fatal error,
99 	 * just return.
100 	 */
101 	if (err == S_ERROR)
102 		return (err);
103 
104 	/*
105 	 * if this is called from, ver_check_defs(), initialize sp.
106 	 */
107 	if (flag == 0)
108 		ver_stk.ver_sp = 0;
109 
110 	/*
111 	 * Check if passed version pointer vp is already in the stack.
112 	 */
113 	for (tmp_sp = 0; tmp_sp < ver_stk.ver_sp; tmp_sp++) {
114 		Ver_desc *v;
115 
116 		v = ver_stk.ver_stk[tmp_sp];
117 		if (v == vp) {
118 			/*
119 			 * cyclic dependency.
120 			 */
121 			if (err == 0) {
122 				eprintf(ofl->ofl_lml, ERR_FATAL,
123 				    MSG_INTL(MSG_VER_CYCLIC));
124 				err = 1;
125 			}
126 			for (tmp_sp = 0; tmp_sp < ver_stk.ver_sp; tmp_sp++) {
127 				v = ver_stk.ver_stk[tmp_sp];
128 				if ((v->vd_flags & FLG_VER_CYCLIC) == 0) {
129 					v->vd_flags |= FLG_VER_CYCLIC;
130 					eprintf(ofl->ofl_lml, ERR_NONE,
131 					    MSG_INTL(MSG_VER_ADDVER),
132 					    v->vd_name);
133 				}
134 			}
135 			if ((vp->vd_flags & FLG_VER_CYCLIC) == 0) {
136 				vp->vd_flags |= FLG_VER_CYCLIC;
137 				eprintf(ofl->ofl_lml, ERR_NONE,
138 				    MSG_INTL(MSG_VER_ADDVER), vp->vd_name);
139 			}
140 			return (err);
141 		}
142 	}
143 
144 	/*
145 	 * Push version on the stack.
146 	 */
147 	if (ver_stk.ver_sp >= ver_stk.ver_lmt) {
148 		ver_stk.ver_lmt += _NUM_OF_VERS_;
149 		if ((ver_stk.ver_stk = (Ver_desc **)
150 		    libld_realloc((void *)ver_stk.ver_stk,
151 		    ver_stk.ver_lmt * sizeof (Ver_desc *))) == NULL)
152 			return (S_ERROR);
153 	}
154 	ver_stk.ver_stk[(ver_stk.ver_sp)++] = vp;
155 
156 	/*
157 	 * Now visit children.
158 	 */
159 	for (APLIST_TRAVERSE(vp->vd_deps, idx, vdp))
160 		if (vers_visit_children(ofl, vdp, 1) == S_ERROR)
161 			return (S_ERROR);
162 
163 	/*
164 	 * Pop version from the stack.
165 	 */
166 	(ver_stk.ver_sp)--;
167 
168 	return (err);
169 }
170 
171 uintptr_t
172 ld_vers_check_defs(Ofl_desc *ofl)
173 {
174 	Aliste		idx1;
175 	Ver_desc	*vdp;
176 	uintptr_t 	is_cyclic = 0;
177 
178 	DBG_CALL(Dbg_ver_def_title(ofl->ofl_lml, ofl->ofl_name));
179 
180 	/*
181 	 * First check if there are any cyclic dependency
182 	 */
183 	for (APLIST_TRAVERSE(ofl->ofl_verdesc, idx1, vdp))
184 		if ((is_cyclic = vers_visit_children(ofl, vdp, 0)) == S_ERROR)
185 			return (S_ERROR);
186 
187 	if (is_cyclic)
188 		ofl->ofl_flags |= FLG_OF_FATAL;
189 
190 	for (APLIST_TRAVERSE(ofl->ofl_verdesc, idx1, vdp)) {
191 		Byte		cnt;
192 		Sym		*sym;
193 		Sym_desc	*sdp;
194 		const char	*name = vdp->vd_name;
195 		uchar_t		bind;
196 		Ver_desc	*_vdp;
197 		avl_index_t	where;
198 		Aliste		idx2;
199 
200 		if (vdp->vd_ndx == 0) {
201 			eprintf(ofl->ofl_lml, ERR_FATAL,
202 			    MSG_INTL(MSG_VER_UNDEF), name, vdp->vd_ref->vd_name,
203 			    vdp->vd_ref->vd_file->ifl_name);
204 			ofl->ofl_flags |= FLG_OF_FATAL;
205 			continue;
206 		}
207 
208 		DBG_CALL(Dbg_ver_desc_entry(ofl->ofl_lml, vdp));
209 
210 		/*
211 		 * If a version definition contains no symbols this is possibly
212 		 * a mapfile error.
213 		 */
214 		if ((vdp->vd_flags &
215 		    (VER_FLG_BASE | VER_FLG_WEAK | FLG_VER_REFER)) == 0)
216 			DBG_CALL(Dbg_ver_nointerface(ofl->ofl_lml,
217 			    vdp->vd_name));
218 
219 		/*
220 		 * Update the version entry count to account for this new
221 		 * version descriptor (the count is the size in bytes).
222 		 */
223 		ofl->ofl_verdefsz += sizeof (Verdef);
224 
225 		/*
226 		 * Traverse this versions dependency list to determine what
227 		 * additional version dependencies we must account for against
228 		 * this descriptor.
229 		 */
230 		cnt = 1;
231 		for (APLIST_TRAVERSE(vdp->vd_deps, idx2, _vdp)) {
232 #if	defined(__lint)
233 			/* get lint to think `_vdp' is used... */
234 			vdp = _vdp;
235 #endif
236 			cnt++;
237 		}
238 		ofl->ofl_verdefsz += (cnt * sizeof (Verdaux));
239 
240 		/*
241 		 * Except for the base version descriptor, generate an absolute
242 		 * symbol to reflect this version.
243 		 */
244 		if (vdp->vd_flags & VER_FLG_BASE)
245 			continue;
246 
247 		if (vdp->vd_flags & VER_FLG_WEAK)
248 			bind = STB_WEAK;
249 		else
250 			bind = STB_GLOBAL;
251 
252 		if (sdp = ld_sym_find(name, vdp->vd_hash, &where, ofl)) {
253 			/*
254 			 * If the symbol already exists and is undefined or was
255 			 * defined in a shared library, convert it to an
256 			 * absolute.
257 			 */
258 			if ((sdp->sd_sym->st_shndx == SHN_UNDEF) ||
259 			    (sdp->sd_ref != REF_REL_NEED)) {
260 				sdp->sd_shndx = sdp->sd_sym->st_shndx = SHN_ABS;
261 				sdp->sd_sym->st_info =
262 				    ELF_ST_INFO(bind, STT_OBJECT);
263 				sdp->sd_ref = REF_REL_NEED;
264 				sdp->sd_flags |= (FLG_SY_SPECSEC |
265 				    FLG_SY_DEFAULT | FLG_SY_EXPDEF);
266 				sdp->sd_aux->sa_overndx = vdp->vd_ndx;
267 
268 				/*
269 				 * If the reference originated from a mapfile
270 				 * insure we mark the symbol as used.
271 				 */
272 				if (sdp->sd_flags & FLG_SY_MAPREF)
273 					sdp->sd_flags |= FLG_SY_MAPUSED;
274 
275 			} else if ((sdp->sd_flags & FLG_SY_SPECSEC) &&
276 			    (sdp->sd_sym->st_shndx != SHN_ABS) &&
277 			    (sdp->sd_ref == REF_REL_NEED)) {
278 				eprintf(ofl->ofl_lml, ERR_WARNING,
279 				    MSG_INTL(MSG_VER_DEFINED), name,
280 				    sdp->sd_file->ifl_name);
281 			}
282 		} else {
283 			/*
284 			 * If the symbol does not exist create it.
285 			 */
286 			if ((sym = libld_calloc(sizeof (Sym), 1)) == NULL)
287 				return (S_ERROR);
288 
289 			sym->st_shndx = SHN_ABS;
290 			sym->st_info = ELF_ST_INFO(bind, STT_OBJECT);
291 			DBG_CALL(Dbg_ver_symbol(ofl->ofl_lml, name));
292 
293 			if ((sdp = ld_sym_enter(name, sym, vdp->vd_hash,
294 			    vdp->vd_file, ofl, 0, SHN_ABS,
295 			    (FLG_SY_SPECSEC | FLG_SY_DEFAULT | FLG_SY_EXPDEF),
296 			    &where)) == (Sym_desc *)S_ERROR)
297 				return (S_ERROR);
298 
299 			sdp->sd_ref = REF_REL_NEED;
300 			sdp->sd_aux->sa_overndx = vdp->vd_ndx;
301 		}
302 	}
303 	return (1);
304 }
305 
306 /*
307  * Dereference dependencies as a part of normalizing (allows recursion).
308  */
309 static void
310 vers_derefer(Ifl_desc *ifl, Ver_desc *vdp, int weak)
311 {
312 	Aliste		idx;
313 	Ver_desc	*_vdp;
314 	Ver_index	*vip = &ifl->ifl_verndx[vdp->vd_ndx];
315 
316 	/*
317 	 * Set the INFO bit on all dependencies that ld.so.1
318 	 * can skip verification for. These are the dependencies
319 	 * that are inherited by others -- verifying the inheriting
320 	 * version implicitily covers this one.
321 	 *
322 	 * If the head of the list was a weak then we only mark
323 	 * weak dependencies, but if the head of the list was 'strong'
324 	 * we set INFO on all dependencies.
325 	 */
326 	if ((weak && (vdp->vd_flags & VER_FLG_WEAK)) || (!weak))
327 		vip->vi_flags |= VER_FLG_INFO;
328 
329 	for (APLIST_TRAVERSE(vdp->vd_deps, idx, _vdp))
330 		vers_derefer(ifl, _vdp, weak);
331 }
332 
333 /*
334  * If we need to record the versions of any needed dependencies traverse the
335  * shared object dependency list and calculate what version needed entries are
336  * required.
337  */
338 uintptr_t
339 ld_vers_check_need(Ofl_desc *ofl)
340 {
341 	Aliste		idx1;
342 	Ifl_desc	*ifl;
343 	Half		needndx;
344 
345 	/*
346 	 * Versym indexes for needed versions start with the next
347 	 * available version after the final definied version.
348 	 * However, it can never be less than 2. 0 is always for local
349 	 * scope, and 1 is always the first global definition.
350 	 */
351 	needndx = (ofl->ofl_vercnt > 0) ? (ofl->ofl_vercnt + 1) : 2;
352 
353 	/*
354 	 * Traverse the shared object list looking for dependencies.
355 	 */
356 	for (APLIST_TRAVERSE(ofl->ofl_sos, idx1, ifl)) {
357 		Aliste		idx2;
358 		Ver_index	*vip;
359 		Ver_desc	*vdp;
360 		Byte		cnt, need = 0;
361 
362 		if (!(ifl->ifl_flags & FLG_IF_NEEDED))
363 			continue;
364 
365 		if (ifl->ifl_vercnt <= VER_NDX_GLOBAL)
366 			continue;
367 
368 		/*
369 		 * Scan the version index list and if any weak version
370 		 * definition has been referenced by the user promote the
371 		 * dependency to be non-weak.  Weak version dependencies do not
372 		 * cause fatal errors from the runtime linker, non-weak
373 		 * dependencies do.
374 		 */
375 		for (cnt = 0; cnt <= ifl->ifl_vercnt; cnt++) {
376 			vip = &ifl->ifl_verndx[cnt];
377 			vdp = vip->vi_desc;
378 
379 			if ((vip->vi_flags & (FLG_VER_REFER | VER_FLG_WEAK)) ==
380 			    (FLG_VER_REFER | VER_FLG_WEAK))
381 				vdp->vd_flags &= ~VER_FLG_WEAK;
382 
383 			/*
384 			 * Mark any weak reference as referred to so as to
385 			 * simplify normalization and later version dependency
386 			 * manipulation.
387 			 */
388 			if (vip->vi_flags & VER_FLG_WEAK)
389 				vip->vi_flags |= FLG_VER_REFER;
390 		}
391 
392 		/*
393 		 * Scan the version dependency list to normalize the referenced
394 		 * dependencies.  Any needed version that is inherited by
395 		 * another like version is dereferenced as it is not necessary
396 		 * to make this part of the version dependencies.
397 		 */
398 		for (APLIST_TRAVERSE(ifl->ifl_verdesc, idx2, vdp)) {
399 			Aliste		idx3;
400 			Ver_desc	*_vdp;
401 			int		type;
402 
403 			vip = &ifl->ifl_verndx[vdp->vd_ndx];
404 
405 			if (!(vip->vi_flags & FLG_VER_REFER))
406 				continue;
407 
408 			type = vdp->vd_flags & VER_FLG_WEAK;
409 			for (APLIST_TRAVERSE(vdp->vd_deps, idx3, _vdp))
410 				vers_derefer(ifl, _vdp, type);
411 		}
412 
413 		/*
414 		 * Finally, determine how many of the version dependencies need
415 		 * to be recorded.
416 		 */
417 		for (cnt = 0; cnt <= ifl->ifl_vercnt; cnt++) {
418 			vip = &ifl->ifl_verndx[cnt];
419 
420 			/*
421 			 * If a version has been referenced then record it as a
422 			 * version dependency.
423 			 */
424 			if (vip->vi_flags & FLG_VER_REFER) {
425 				/* Assign a VERSYM index for it */
426 				vip->vi_overndx = needndx++;
427 
428 				ofl->ofl_verneedsz += sizeof (Vernaux);
429 				if (st_insert(ofl->ofl_dynstrtab,
430 				    vip->vi_name) == -1)
431 					return (S_ERROR);
432 				need++;
433 			}
434 		}
435 
436 		if (need) {
437 			ifl->ifl_flags |= FLG_IF_VERNEED;
438 			ofl->ofl_verneedsz += sizeof (Verneed);
439 			if (st_insert(ofl->ofl_dynstrtab,
440 			    ifl->ifl_soname) == -1)
441 				return (S_ERROR);
442 		}
443 	}
444 
445 	/*
446 	 * If no version needed information is required unset the output file
447 	 * flag.
448 	 */
449 	if (ofl->ofl_verneedsz == 0)
450 		ofl->ofl_flags &= ~FLG_OF_VERNEED;
451 
452 	return (1);
453 }
454 
455 /*
456  * Indicate dependency selection (allows recursion).
457  */
458 static void
459 vers_select(Ofl_desc *ofl, Ifl_desc *ifl, Ver_desc *vdp, const char *ref)
460 {
461 	Aliste		idx;
462 	Ver_desc	*_vdp;
463 	Ver_index	*vip = &ifl->ifl_verndx[vdp->vd_ndx];
464 
465 	vip->vi_flags |= FLG_VER_AVAIL;
466 	DBG_CALL(Dbg_ver_avail_entry(ofl->ofl_lml, vip, ref));
467 
468 	for (APLIST_TRAVERSE(vdp->vd_deps, idx, _vdp))
469 		vers_select(ofl, ifl, _vdp, ref);
470 }
471 
472 static Ver_index *
473 vers_index(Ofl_desc *ofl, Ifl_desc *ifl, int avail)
474 {
475 	Aliste		idx1;
476 	Ver_desc	*vdp;
477 	Ver_index	*vip;
478 	Sdf_desc	*sdf = ifl->ifl_sdfdesc;
479 	Word		count = ifl->ifl_vercnt;
480 	Sdv_desc	*sdv;
481 
482 	/*
483 	 * Allocate an index array large enough to hold all of the files
484 	 * version descriptors.
485 	 */
486 	if ((vip = libld_calloc(sizeof (Ver_index), (count + 1))) == NULL)
487 		return ((Ver_index *)S_ERROR);
488 
489 	for (APLIST_TRAVERSE(ifl->ifl_verdesc, idx1, vdp)) {
490 		int	ndx = vdp->vd_ndx;
491 
492 		vip[ndx].vi_name = vdp->vd_name;
493 		vip[ndx].vi_desc = vdp;
494 
495 		/*
496 		 * Any relocatable object versions, and the `base' version are
497 		 * always available.
498 		 */
499 		if (avail || (vdp->vd_flags & VER_FLG_BASE))
500 			vip[ndx].vi_flags |= FLG_VER_AVAIL;
501 
502 		/*
503 		 * If this is a weak version mark it as such.  Weak versions
504 		 * are always dragged into any version dependencies created,
505 		 * and if a weak version is referenced it will be promoted to
506 		 * a non-weak version dependency.
507 		 */
508 		if (vdp->vd_flags & VER_FLG_WEAK)
509 			vip[ndx].vi_flags |= VER_FLG_WEAK;
510 		/*
511 		 * If this version is mentioned in a mapfile using ADDVERS
512 		 * syntax then check to see if it corresponds to an actual
513 		 * version in the file.
514 		 */
515 		if (sdf && (sdf->sdf_flags & FLG_SDF_ADDVER)) {
516 			Aliste	idx2;
517 
518 			for (ALIST_TRAVERSE(sdf->sdf_verneed, idx2, sdv)) {
519 				if (strcmp(vip[ndx].vi_name, sdv->sdv_name))
520 					continue;
521 
522 				vip[ndx].vi_flags |= FLG_VER_REFER;
523 				sdv->sdv_flags |= FLG_SDV_MATCHED;
524 				break;
525 			}
526 		}
527 	}
528 
529 	/*
530 	 * if $ADDVER was specified for this object verify that
531 	 * all of it's dependent upon versions were refered to.
532 	 */
533 	if (sdf && (sdf->sdf_flags & FLG_SDF_ADDVER)) {
534 		int	fail = 0;
535 
536 		for (ALIST_TRAVERSE(sdf->sdf_verneed, idx1, sdv)) {
537 			if (sdv->sdv_flags & FLG_SDV_MATCHED)
538 				continue;
539 
540 			if (fail++ == 0) {
541 				eprintf(ofl->ofl_lml, ERR_NONE,
542 				    MSG_INTL(MSG_VER_ADDVERS), sdf->sdf_rfile,
543 				    sdf->sdf_name);
544 			}
545 			eprintf(ofl->ofl_lml, ERR_NONE,
546 			    MSG_INTL(MSG_VER_ADDVER), sdv->sdv_name);
547 		}
548 		if (fail)
549 			return ((Ver_index *)S_ERROR);
550 	}
551 
552 	return (vip);
553 }
554 
555 /*
556  * Process a version symbol index section.
557  */
558 int
559 ld_vers_sym_process(Lm_list *lml, Is_desc *isp, Ifl_desc *ifl)
560 {
561 	Shdr	*symshdr;
562 	Shdr	*vershdr = isp->is_shdr;
563 
564 	/*
565 	 * Verify that the versym is the same size as the linked symbol table.
566 	 * If these two get out of sync the file is considered corrupted.
567 	 */
568 	symshdr = ifl->ifl_isdesc[vershdr->sh_link]->is_shdr;
569 	if ((symshdr->sh_size / symshdr->sh_entsize) != (vershdr->sh_size /
570 	    vershdr->sh_entsize)) {
571 		Is_desc	*sym_isp = ifl->ifl_isdesc[vershdr->sh_link];
572 
573 		eprintf(lml, ERR_WARNING, MSG_INTL(MSG_ELF_VERSYM),
574 		    ifl->ifl_name, EC_WORD(isp->is_scnndx), isp->is_name,
575 		    EC_WORD(vershdr->sh_size / vershdr->sh_entsize),
576 		    EC_WORD(sym_isp->is_scnndx), sym_isp->is_name,
577 		    EC_WORD(symshdr->sh_size / symshdr->sh_entsize));
578 		return (1);
579 	}
580 	ifl->ifl_versym = (Versym *)isp->is_indata->d_buf;
581 	return (1);
582 }
583 
584 /*
585  * Process a version definition section from an input file.  A list of version
586  * descriptors is created and associated with the input files descriptor.  If
587  * this is a shared object these descriptors will be used to indicate the
588  * availability of each version.  If this is a relocatable object then these
589  * descriptors will be promoted (concatenated) to the output files image.
590  */
591 uintptr_t
592 ld_vers_def_process(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl)
593 {
594 	const char	*str, *file = ifl->ifl_name;
595 	Sdf_desc	*sdf = ifl->ifl_sdfdesc;
596 	Sdv_desc	*sdv;
597 	Word		num, _num;
598 	Verdef		*vdf;
599 	int		relobj;
600 
601 	/*
602 	 * If there is no version section then simply indicate that all version
603 	 * definitions asked for do not exist.
604 	 */
605 	if (isp == NULL) {
606 		Aliste	idx;
607 
608 		for (ALIST_TRAVERSE(sdf->sdf_vers, idx, sdv)) {
609 			eprintf(ofl->ofl_lml, ERR_FATAL,
610 			    MSG_INTL(MSG_VER_NOEXIST), ifl->ifl_name,
611 			    sdv->sdv_name, sdv->sdv_ref);
612 			ofl->ofl_flags |= FLG_OF_FATAL;
613 		}
614 		return (0);
615 	}
616 
617 	vdf = (Verdef *)isp->is_indata->d_buf;
618 
619 	/*
620 	 * Verify the version revision.  We only check the first version
621 	 * structure as it is assumed all other version structures in this
622 	 * data section will be of the same revision.
623 	 */
624 	if (vdf->vd_version > VER_DEF_CURRENT)
625 		(void) eprintf(ofl->ofl_lml, ERR_WARNING,
626 		    MSG_INTL(MSG_VER_HIGHER), ifl->ifl_name, vdf->vd_version,
627 		    VER_DEF_CURRENT);
628 
629 
630 	num = isp->is_shdr->sh_info;
631 	str = (char *)ifl->ifl_isdesc[isp->is_shdr->sh_link]->is_indata->d_buf;
632 
633 	if (ifl->ifl_ehdr->e_type == ET_REL)
634 		relobj = 1;
635 	else
636 		relobj = 0;
637 
638 	DBG_CALL(Dbg_ver_def_title(ofl->ofl_lml, file));
639 
640 	/*
641 	 * Loop through the version information setting up a version descriptor
642 	 * for each version definition.
643 	 */
644 	for (_num = 1; _num <= num; _num++,
645 	    vdf = (Verdef *)((uintptr_t)vdf + vdf->vd_next)) {
646 		const char	*name;
647 		Ver_desc	*ivdp, *ovdp = NULL;
648 		Word		hash;
649 		Half 		cnt = vdf->vd_cnt;
650 		Half		ndx = vdf->vd_ndx;
651 		Verdaux		*vdap = (Verdaux *)((uintptr_t)vdf +
652 		    vdf->vd_aux);
653 
654 		/*
655 		 * Keep track of the largest index for use in creating a
656 		 * version index array later, and create a version descriptor.
657 		 */
658 		if (ndx > ifl->ifl_vercnt)
659 			ifl->ifl_vercnt = ndx;
660 
661 		name = (char *)(str + vdap->vda_name);
662 		/* LINTED */
663 		hash = (Word)elf_hash(name);
664 		if (((ivdp = ld_vers_find(name, hash,
665 		    ifl->ifl_verdesc)) == NULL) &&
666 		    ((ivdp = ld_vers_desc(name, hash,
667 		    &ifl->ifl_verdesc)) == (Ver_desc *)S_ERROR))
668 			return (S_ERROR);
669 
670 		ivdp->vd_ndx = ndx;
671 		ivdp->vd_file = ifl;
672 		ivdp->vd_flags = vdf->vd_flags;
673 
674 		/*
675 		 * If we're processing a relocatable object then this version
676 		 * definition needs to be propagated to the output file.
677 		 * Generate a new output file version and associated this input
678 		 * version to it.  During symbol processing the version index of
679 		 * the symbol will be promoted from the input file to the output
680 		 * files version definition.
681 		 */
682 		if (relobj) {
683 			if (!(ofl->ofl_flags & FLG_OF_RELOBJ))
684 				ofl->ofl_flags |= FLG_OF_PROCRED;
685 
686 			if ((ivdp->vd_flags & VER_FLG_BASE) == 0) {
687 				/*
688 				 * If no version descriptors have yet been set
689 				 * up, initialize a base version to represent
690 				 * the output file itself.  This `base' version
691 				 * catches any internally generated symbols
692 				 * (_end, _etext, etc.) and
693 				 * serves to initialize the output version
694 				 * descriptor count.
695 				 */
696 				if (ofl->ofl_vercnt == 0) {
697 					if (ld_vers_base(ofl) ==
698 					    (Ver_desc *)S_ERROR)
699 						return (S_ERROR);
700 				}
701 				ofl->ofl_flags |= FLG_OF_VERDEF;
702 				if ((ovdp = ld_vers_find(name, hash,
703 				    ofl->ofl_verdesc)) == NULL) {
704 					if ((ovdp = ld_vers_desc(name, hash,
705 					    &ofl->ofl_verdesc)) ==
706 					    (Ver_desc *)S_ERROR)
707 						return (S_ERROR);
708 
709 					/* LINTED */
710 					ovdp->vd_ndx = (Half)++ofl->ofl_vercnt;
711 					ovdp->vd_file = ifl;
712 					ovdp->vd_flags = vdf->vd_flags;
713 				}
714 			}
715 
716 			/*
717 			 * Maintain the association between the input version
718 			 * descriptor and the output version descriptor so that
719 			 * an associated symbols will be assigned to the
720 			 * correct version.
721 			 */
722 			ivdp->vd_ref = ovdp;
723 		}
724 
725 		/*
726 		 * Process any dependencies this version may have.
727 		 */
728 		vdap = (Verdaux *)((uintptr_t)vdap + vdap->vda_next);
729 		for (cnt--; cnt; cnt--,
730 		    vdap = (Verdaux *)((uintptr_t)vdap + vdap->vda_next)) {
731 			Ver_desc	*_ivdp;
732 
733 			name = (char *)(str + vdap->vda_name);
734 			/* LINTED */
735 			hash = (Word)elf_hash(name);
736 
737 			if (((_ivdp = ld_vers_find(name, hash,
738 			    ifl->ifl_verdesc)) == NULL) &&
739 			    ((_ivdp = ld_vers_desc(name, hash,
740 			    &ifl->ifl_verdesc)) == (Ver_desc *)S_ERROR))
741 				return (S_ERROR);
742 
743 			if (aplist_append(&ivdp->vd_deps, _ivdp,
744 			    AL_CNT_VERDESCS) == NULL)
745 				return (S_ERROR);
746 		}
747 		DBG_CALL(Dbg_ver_desc_entry(ofl->ofl_lml, ivdp));
748 	}
749 
750 	/*
751 	 * Now that we know the total number of version definitions for this
752 	 * file, build an index array for fast access when processing symbols.
753 	 */
754 	if ((ifl->ifl_verndx =
755 	    vers_index(ofl, ifl, relobj)) == (Ver_index *)S_ERROR)
756 		return (S_ERROR);
757 
758 	if (relobj)
759 		return (1);
760 
761 	/*
762 	 * If this object has version control definitions against it then these
763 	 * must be processed so as to select those version definitions to which
764 	 * symbol bindings can occur.  Otherwise simply mark all versions as
765 	 * available.
766 	 */
767 	DBG_CALL(Dbg_ver_avail_title(ofl->ofl_lml, file));
768 
769 	if (sdf && (sdf->sdf_flags & FLG_SDF_SELECT)) {
770 		Aliste	idx1;
771 
772 		for (ALIST_TRAVERSE(sdf->sdf_vers, idx1, sdv)) {
773 			Aliste		idx2;
774 			Ver_desc	*vdp;
775 			int		found = 0;
776 
777 			for (APLIST_TRAVERSE(ifl->ifl_verdesc, idx2, vdp)) {
778 				if (strcmp(sdv->sdv_name, vdp->vd_name) == 0) {
779 					found++;
780 					break;
781 				}
782 			}
783 			if (found)
784 				vers_select(ofl, ifl, vdp, sdv->sdv_ref);
785 			else {
786 				eprintf(ofl->ofl_lml, ERR_FATAL,
787 				    MSG_INTL(MSG_VER_NOEXIST), ifl->ifl_name,
788 				    sdv->sdv_name, sdv->sdv_ref);
789 				ofl->ofl_flags |= FLG_OF_FATAL;
790 			}
791 		}
792 	} else {
793 		Ver_index	*vip;
794 		int		cnt;
795 
796 		for (cnt = VER_NDX_GLOBAL; cnt <= ifl->ifl_vercnt; cnt++) {
797 			vip = &ifl->ifl_verndx[cnt];
798 			vip->vi_flags |= FLG_VER_AVAIL;
799 			DBG_CALL(Dbg_ver_avail_entry(ofl->ofl_lml, vip, 0));
800 		}
801 	}
802 
803 	/*
804 	 * If this is an explict dependency indicate that this file is a
805 	 * candidate for requiring version needed information to be recorded in
806 	 * the image we're creating.
807 	 */
808 	if (ifl->ifl_flags & FLG_IF_NEEDED)
809 		ofl->ofl_flags |= FLG_OF_VERNEED;
810 
811 	return (1);
812 }
813 
814 /*
815  * Process a version needed section.
816  */
817 uintptr_t
818 ld_vers_need_process(Is_desc *isp, Ifl_desc *ifl, Ofl_desc *ofl)
819 {
820 	const char	*str, *file = ifl->ifl_name;
821 	Word		num, _num;
822 	Verneed		*vnd;
823 
824 	vnd = (Verneed *)isp->is_indata->d_buf;
825 
826 	/*
827 	 * Verify the version revision.  We only check the first version
828 	 * structure as it is assumed all other version structures in this
829 	 * data section will be of the same revision.
830 	 */
831 	if (vnd->vn_version > VER_DEF_CURRENT) {
832 		(void) eprintf(ofl->ofl_lml, ERR_WARNING,
833 		    MSG_INTL(MSG_VER_HIGHER), ifl->ifl_name, vnd->vn_version,
834 		    VER_DEF_CURRENT);
835 	}
836 
837 	num = isp->is_shdr->sh_info;
838 	str = (char *)ifl->ifl_isdesc[isp->is_shdr->sh_link]->is_indata->d_buf;
839 
840 	DBG_CALL(Dbg_ver_need_title(ofl->ofl_lml, file));
841 
842 	/*
843 	 * Loop through the version information setting up a version descriptor
844 	 * for each version definition.
845 	 */
846 	for (_num = 1; _num <= num; _num++,
847 	    vnd = (Verneed *)((uintptr_t)vnd + vnd->vn_next)) {
848 		Sdf_desc	*sdf;
849 		const char	*name;
850 		Half		cnt = vnd->vn_cnt;
851 		Vernaux		*vnap = (Vernaux *)((uintptr_t)vnd +
852 		    vnd->vn_aux);
853 		Half		_cnt;
854 
855 		name = (char *)(str + vnd->vn_file);
856 
857 		/*
858 		 * Set up a shared object descriptor and add to it the necessary
859 		 * needed versions.  This information may also have been added
860 		 * by a mapfile (see map_dash()).
861 		 */
862 		if ((sdf = sdf_find(name, ofl->ofl_soneed)) == NULL) {
863 			if ((sdf = sdf_add(name, &ofl->ofl_soneed)) ==
864 			    (Sdf_desc *)S_ERROR)
865 				return (S_ERROR);
866 			sdf->sdf_rfile = file;
867 			sdf->sdf_flags |= FLG_SDF_VERIFY;
868 		}
869 
870 		for (_cnt = 0; cnt; _cnt++, cnt--,
871 		    vnap = (Vernaux *)((uintptr_t)vnap + vnap->vna_next)) {
872 			Sdv_desc	sdv;
873 
874 			sdv.sdv_name = str + vnap->vna_name;
875 			sdv.sdv_ref = file;
876 			sdv.sdv_flags = 0;
877 
878 			if (alist_append(&sdf->sdf_vers, &sdv,
879 			    sizeof (Sdv_desc), AL_CNT_SDF_VERSIONS) == NULL)
880 				return (S_ERROR);
881 
882 			DBG_CALL(Dbg_ver_need_entry(ofl->ofl_lml, _cnt, name,
883 			    sdv.sdv_name));
884 		}
885 	}
886 	return (1);
887 }
888 
889 /*
890  * If a symbol is obtained from a versioned relocatable object then the symbols
891  * version association must be promoted to the version definition as it will be
892  * represented in the output file.
893  */
894 void
895 ld_vers_promote(Sym_desc *sdp, Word ndx, Ifl_desc *ifl, Ofl_desc *ofl)
896 {
897 	Half 	vndx;
898 
899 	/*
900 	 * A version symbol index of 0 implies the symbol is local.  A value of
901 	 * VER_NDX_GLOBAL implies the symbol is global but has not been
902 	 * assigned to a specfic version definition.
903 	 */
904 	vndx = ifl->ifl_versym[ndx];
905 	if (vndx == 0) {
906 		sdp->sd_flags |= (FLG_SY_REDUCED | FLG_SY_HIDDEN);
907 		return;
908 	}
909 
910 	if (vndx == VER_NDX_ELIMINATE) {
911 		sdp->sd_flags |= (FLG_SY_REDUCED | FLG_SY_HIDDEN | FLG_SY_ELIM);
912 		return;
913 	}
914 
915 	if (vndx == VER_NDX_GLOBAL) {
916 		if ((sdp->sd_flags & FLG_SY_HIDDEN) == 0)
917 			sdp->sd_flags |= (FLG_SY_DEFAULT | FLG_SY_EXPDEF);
918 		if (sdp->sd_aux->sa_overndx <= VER_NDX_GLOBAL)
919 			sdp->sd_aux->sa_overndx = VER_NDX_GLOBAL;
920 		return;
921 	}
922 
923 	/*
924 	 * Any other version index requires association to the appropriate
925 	 * version definition.
926 	 */
927 	if ((ifl->ifl_verndx == 0) || (vndx > ifl->ifl_vercnt)) {
928 		eprintf(ofl->ofl_lml, ERR_FATAL, MSG_INTL(MSG_VER_INVALNDX),
929 		    sdp->sd_name, ifl->ifl_name, vndx);
930 		ofl->ofl_flags |= FLG_OF_FATAL;
931 		return;
932 	}
933 
934 	if ((sdp->sd_flags & FLG_SY_HIDDEN) == 0)
935 		sdp->sd_flags |= (FLG_SY_DEFAULT | FLG_SY_EXPDEF);
936 
937 	/*
938 	 * Promote the symbols version index to the appropriate output version
939 	 * definition.
940 	 */
941 	if (!(sdp->sd_flags & FLG_SY_VERSPROM)) {
942 		Ver_index	*vip;
943 
944 		vip = &ifl->ifl_verndx[vndx];
945 		sdp->sd_aux->sa_overndx = vip->vi_desc->vd_ref->vd_ndx;
946 		sdp->sd_flags |= FLG_SY_VERSPROM;
947 	}
948 }
949 
950 /*
951  * If any versioning is called for make sure an initial version descriptor is
952  * assigned to represent the file itself.  Known as the base version.
953  */
954 Ver_desc *
955 ld_vers_base(Ofl_desc *ofl)
956 {
957 	Ver_desc	*vdp;
958 	const char	*name;
959 
960 	/*
961 	 * Determine the filename to associate to the version descriptor.  This
962 	 * is either the SONAME (if one has been supplied) or the basename of
963 	 * the output file.
964 	 */
965 	if ((name = ofl->ofl_soname) == NULL) {
966 		const char	*str = ofl->ofl_name;
967 
968 		while (*str != '\0') {
969 			if (*str++ == '/')
970 				name = str;
971 		}
972 		if (name == NULL)
973 			name = ofl->ofl_name;
974 	}
975 
976 	/*
977 	 * Generate the version descriptor.
978 	 */
979 	/* LINTED */
980 	if ((vdp = ld_vers_desc(name, (Word)elf_hash(name),
981 	    &ofl->ofl_verdesc)) == (Ver_desc *)S_ERROR)
982 		return ((Ver_desc *)S_ERROR);
983 
984 	/*
985 	 * Assign the base index to this version and initialize the output file
986 	 * descriptor with the number of version descriptors presently in use.
987 	 */
988 	vdp->vd_ndx = ofl->ofl_vercnt = VER_NDX_GLOBAL;
989 	vdp->vd_flags |= VER_FLG_BASE;
990 
991 	return (vdp);
992 }
993 
994 /*
995  * Now that all input shared objects have been processed, verify that all
996  * version requirements have been met.  Any version control requirements will
997  * have been specified by the user (and placed on the ofl_oscntl list) and are
998  * verified at the time the object was processed (see ver_def_process()).
999  * Here we process all version requirements established from shared objects
1000  * themselves (ie,. NEEDED dependencies).
1001  */
1002 int
1003 ld_vers_verify(Ofl_desc *ofl)
1004 {
1005 	Aliste		idx1;
1006 	Sdf_desc	*sdf;
1007 	char		*nv;
1008 
1009 	/*
1010 	 * As with the runtime environment, disable all version verification if
1011 	 * requested.
1012 	 */
1013 #if	defined(_ELF64)
1014 	if ((nv = getenv(MSG_ORIG(MSG_LD_NOVERSION_64))) == NULL)
1015 #else
1016 	if ((nv = getenv(MSG_ORIG(MSG_LD_NOVERSION_32))) == NULL)
1017 #endif
1018 		nv = getenv(MSG_ORIG(MSG_LD_NOVERSION));
1019 
1020 	if (nv && (*nv != '\0'))
1021 		return (1);
1022 
1023 	for (APLIST_TRAVERSE(ofl->ofl_soneed, idx1, sdf)) {
1024 		Aliste		idx2;
1025 		Sdv_desc	*sdv;
1026 		Ifl_desc	*ifl = sdf->sdf_file;
1027 
1028 		if (!(sdf->sdf_flags & FLG_SDF_VERIFY))
1029 			continue;
1030 
1031 		/*
1032 		 * If this file contains no version definitions then ignore
1033 		 * any versioning verification.  This is the same model as
1034 		 * carried out by ld.so.1 and is intended to allow backward
1035 		 * compatibility should a shared object with a version
1036 		 * requirement be returned to an older system on which a
1037 		 * non-versioned shared object exists.
1038 		 */
1039 		if ((ifl == NULL) || (ifl->ifl_verdesc == NULL))
1040 			continue;
1041 
1042 		/*
1043 		 * If individual versions were specified for this file make
1044 		 * sure that they actually exist in the appropriate file, and
1045 		 * that they are available for binding.
1046 		 */
1047 		for (ALIST_TRAVERSE(sdf->sdf_vers, idx2, sdv)) {
1048 			Aliste		idx3;
1049 			Ver_desc	*vdp;
1050 			int		found = 0;
1051 
1052 			for (APLIST_TRAVERSE(ifl->ifl_verdesc, idx3, vdp)) {
1053 				if (strcmp(sdv->sdv_name, vdp->vd_name) == 0) {
1054 					found++;
1055 					break;
1056 				}
1057 			}
1058 			if (found) {
1059 				Ver_index	*vip;
1060 
1061 				vip = &ifl->ifl_verndx[vdp->vd_ndx];
1062 				if (!(vip->vi_flags & FLG_VER_AVAIL)) {
1063 					eprintf(ofl->ofl_lml, ERR_FATAL,
1064 					    MSG_INTL(MSG_VER_UNAVAIL),
1065 					    ifl->ifl_name, sdv->sdv_name,
1066 					    sdv->sdv_ref);
1067 					ofl->ofl_flags |= FLG_OF_FATAL;
1068 				}
1069 			} else {
1070 				eprintf(ofl->ofl_lml, ERR_FATAL,
1071 				    MSG_INTL(MSG_VER_NOEXIST), ifl->ifl_name,
1072 				    sdv->sdv_name, sdv->sdv_ref);
1073 				ofl->ofl_flags |= FLG_OF_FATAL;
1074 			}
1075 		}
1076 	}
1077 	return (1);
1078 }
1079