i386_elf.c revision 11827:d7ef53deac3f
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 2010 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*
28 *	Copyright (c) 1988 AT&T
29 *	  All Rights Reserved
30 */
31
32/*
33 * x86 machine dependent and ELF file class dependent functions.
34 * Contains routines for performing function binding and symbol relocations.
35 */
36
37#include	<stdio.h>
38#include	<sys/elf.h>
39#include	<sys/elf_386.h>
40#include	<sys/mman.h>
41#include	<dlfcn.h>
42#include	<synch.h>
43#include	<string.h>
44#include	<debug.h>
45#include	<reloc.h>
46#include	<conv.h>
47#include	"_rtld.h"
48#include	"_audit.h"
49#include	"_elf.h"
50#include	"_inline.h"
51#include	"msg.h"
52
53extern void	elf_rtbndr(Rt_map *, ulong_t, caddr_t);
54
55int
56elf_mach_flags_check(Rej_desc *rej, Ehdr *ehdr)
57{
58	/*
59	 * Check machine type and flags.
60	 */
61	if (ehdr->e_flags != 0) {
62		rej->rej_type = SGS_REJ_BADFLAG;
63		rej->rej_info = (uint_t)ehdr->e_flags;
64		return (0);
65	}
66	return (1);
67}
68
69void
70ldso_plt_init(Rt_map *lmp)
71{
72	/*
73	 * There is no need to analyze ld.so because we don't map in any of
74	 * its dependencies.  However we may map these dependencies in later
75	 * (as if ld.so had dlopened them), so initialize the plt and the
76	 * permission information.
77	 */
78	if (PLTGOT(lmp))
79		elf_plt_init((PLTGOT(lmp)), (caddr_t)lmp);
80}
81
82static const uchar_t dyn_plt_template[] = {
83/* 0x00 */  0x55,				/* pushl %ebp */
84/* 0x01 */  0x8b, 0xec,				/* movl %esp, %ebp */
85/* 0x03 */  0x68, 0x00, 0x00, 0x00, 0x00,	/* pushl trace_fields */
86/* 0x08 */  0xe9, 0xfc, 0xff, 0xff, 0xff, 0xff	/* jmp  elf_plt_trace */
87};
88int	dyn_plt_ent_size = sizeof (dyn_plt_template);
89
90/*
91 * the dynamic plt entry is:
92 *
93 *	pushl	%ebp
94 *	movl	%esp, %ebp
95 *	pushl	tfp
96 *	jmp	elf_plt_trace
97 * dyn_data:
98 *	.align  4
99 *	uintptr_t	reflmp
100 *	uintptr_t	deflmp
101 *	uint_t		symndx
102 *	uint_t		sb_flags
103 *	Sym		symdef
104 */
105static caddr_t
106elf_plt_trace_write(uint_t roffset, Rt_map *rlmp, Rt_map *dlmp, Sym *sym,
107    uint_t symndx, uint_t pltndx, caddr_t to, uint_t sb_flags, int *fail)
108{
109	extern int	elf_plt_trace();
110	ulong_t		got_entry;
111	uchar_t		*dyn_plt;
112	uintptr_t	*dyndata;
113
114	/*
115	 * We only need to add the glue code if there is an auditing
116	 * library that is interested in this binding.
117	 */
118	dyn_plt = (uchar_t *)((uintptr_t)AUDINFO(rlmp)->ai_dynplts +
119	    (pltndx * dyn_plt_ent_size));
120
121	/*
122	 * Have we initialized this dynamic plt entry yet?  If we haven't do it
123	 * now.  Otherwise this function has been called before, but from a
124	 * different plt (ie. from another shared object).  In that case
125	 * we just set the plt to point to the new dyn_plt.
126	 */
127	if (*dyn_plt == 0) {
128		Sym	*symp;
129		Word	symvalue;
130		Lm_list	*lml = LIST(rlmp);
131
132		(void) memcpy((void *)dyn_plt, dyn_plt_template,
133		    sizeof (dyn_plt_template));
134		dyndata = (uintptr_t *)((uintptr_t)dyn_plt +
135		    ROUND(sizeof (dyn_plt_template), M_WORD_ALIGN));
136
137		/*
138		 * relocate:
139		 *	pushl	dyn_data
140		 */
141		symvalue = (Word)dyndata;
142		if (do_reloc_rtld(R_386_32, &dyn_plt[4], &symvalue,
143		    MSG_ORIG(MSG_SYM_LADYNDATA),
144		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
145			*fail = 1;
146			return (0);
147		}
148
149		/*
150		 * jmps are relative, so I need to figure out the relative
151		 * address to elf_plt_trace.
152		 *
153		 * relocating:
154		 *	jmp	elf_plt_trace
155		 */
156		symvalue = (ulong_t)(elf_plt_trace) - (ulong_t)(dyn_plt + 9);
157		if (do_reloc_rtld(R_386_PC32, &dyn_plt[9], &symvalue,
158		    MSG_ORIG(MSG_SYM_ELFPLTTRACE),
159		    MSG_ORIG(MSG_SPECFIL_DYNPLT), lml) == 0) {
160			*fail = 1;
161			return (0);
162		}
163
164		*dyndata++ = (uintptr_t)rlmp;
165		*dyndata++ = (uintptr_t)dlmp;
166		*dyndata++ = (uint_t)symndx;
167		*dyndata++ = (uint_t)sb_flags;
168		symp = (Sym *)dyndata;
169		*symp = *sym;
170		symp->st_name += (Word)STRTAB(dlmp);
171		symp->st_value = (Addr)to;
172	}
173
174	got_entry = (ulong_t)roffset;
175	*(ulong_t *)got_entry = (ulong_t)dyn_plt;
176	return ((caddr_t)dyn_plt);
177}
178
179/*
180 * Function binding routine - invoked on the first call to a function through
181 * the procedure linkage table;
182 * passes first through an assembly language interface.
183 *
184 * Takes the offset into the relocation table of the associated
185 * relocation entry and the address of the link map (rt_private_map struct)
186 * for the entry.
187 *
188 * Returns the address of the function referenced after re-writing the PLT
189 * entry to invoke the function directly.
190 *
191 * On error, causes process to terminate with a signal.
192 */
193ulong_t
194elf_bndr(Rt_map *lmp, ulong_t reloff, caddr_t from)
195{
196	Rt_map		*nlmp, *llmp;
197	ulong_t		addr, symval, rsymndx;
198	char		*name;
199	Rel		*rptr;
200	Sym		*rsym, *nsym;
201	uint_t		binfo, sb_flags = 0, dbg_class;
202	Slookup		sl;
203	Sresult		sr;
204	int		entry, lmflags;
205	Lm_list		*lml;
206
207	/*
208	 * For compatibility with libthread (TI_VERSION 1) we track the entry
209	 * value.  A zero value indicates we have recursed into ld.so.1 to
210	 * further process a locking request.  Under this recursion we disable
211	 * tsort and cleanup activities.
212	 */
213	entry = enter(0);
214
215	lml = LIST(lmp);
216	if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) {
217		dbg_class = dbg_desc->d_class;
218		dbg_desc->d_class = 0;
219	}
220
221	/*
222	 * Perform some basic sanity checks.  If we didn't get a load map or
223	 * the relocation offset is invalid then its possible someone has walked
224	 * over the .got entries or jumped to plt0 out of the blue.
225	 */
226	if (!lmp || ((reloff % sizeof (Rel)) != 0)) {
227		Conv_inv_buf_t inv_buf;
228
229		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF),
230		    conv_reloc_386_type(R_386_JMP_SLOT, 0, &inv_buf),
231		    EC_NATPTR(lmp), EC_XWORD(reloff), EC_NATPTR(from));
232		rtldexit(lml, 1);
233	}
234
235	/*
236	 * Use relocation entry to get symbol table entry and symbol name.
237	 */
238	addr = (ulong_t)JMPREL(lmp);
239	rptr = (Rel *)(addr + reloff);
240	rsymndx = ELF_R_SYM(rptr->r_info);
241	rsym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp)));
242	name = (char *)(STRTAB(lmp) + rsym->st_name);
243
244	/*
245	 * Determine the last link-map of this list, this'll be the starting
246	 * point for any tsort() processing.
247	 */
248	llmp = lml->lm_tail;
249
250	/*
251	 * Find definition for symbol.  Initialize the symbol lookup, and
252	 * symbol result, data structures.
253	 */
254	SLOOKUP_INIT(sl, name, lmp, lml->lm_head, ld_entry_cnt, 0,
255	    rsymndx, rsym, 0, LKUP_DEFT);
256	SRESULT_INIT(sr, name);
257
258	if (lookup_sym(&sl, &sr, &binfo, NULL) == 0) {
259		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
260		    demangle(name));
261		rtldexit(lml, 1);
262	}
263
264	name = (char *)sr.sr_name;
265	nlmp = sr.sr_dmap;
266	nsym = sr.sr_sym;
267
268	symval = nsym->st_value;
269
270	if (!(FLAGS(nlmp) & FLG_RT_FIXED) &&
271	    (nsym->st_shndx != SHN_ABS))
272		symval += ADDR(nlmp);
273	if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) {
274		/*
275		 * Record that this new link map is now bound to the caller.
276		 */
277		if (bind_one(lmp, nlmp, BND_REFER) == 0)
278			rtldexit(lml, 1);
279	}
280
281	if ((lml->lm_tflags | AFLAGS(lmp)) & LML_TFLG_AUD_SYMBIND) {
282		uint_t	symndx = (((uintptr_t)nsym -
283		    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
284		symval = audit_symbind(lmp, nlmp, nsym, symndx, symval,
285		    &sb_flags);
286	}
287
288	if (!(rtld_flags & RT_FL_NOBIND)) {
289		addr = rptr->r_offset;
290		if (!(FLAGS(lmp) & FLG_RT_FIXED))
291			addr += ADDR(lmp);
292		if (((lml->lm_tflags | AFLAGS(lmp)) &
293		    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
294		    AUDINFO(lmp)->ai_dynplts) {
295			int	fail = 0;
296			uint_t	pltndx = reloff / sizeof (Rel);
297			uint_t	symndx = (((uintptr_t)nsym -
298			    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
299
300			symval = (ulong_t)elf_plt_trace_write(addr, lmp, nlmp,
301			    nsym, symndx, pltndx, (caddr_t)symval, sb_flags,
302			    &fail);
303			if (fail)
304				rtldexit(lml, 1);
305		} else {
306			/*
307			 * Write standard PLT entry to jump directly
308			 * to newly bound function.
309			 */
310			*(ulong_t *)addr = symval;
311		}
312	}
313
314	/*
315	 * Print binding information and rebuild PLT entry.
316	 */
317	DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)),
318	    (Xword)(reloff / sizeof (Rel)), PLT_T_FULL, nlmp, (Addr)symval,
319	    nsym->st_value, name, binfo));
320
321	/*
322	 * Complete any processing for newly loaded objects.  Note we don't
323	 * know exactly where any new objects are loaded (we know the object
324	 * that supplied the symbol, but others may have been loaded lazily as
325	 * we searched for the symbol), so sorting starts from the last
326	 * link-map know on entry to this routine.
327	 */
328	if (entry)
329		load_completion(llmp);
330
331	/*
332	 * Some operations like dldump() or dlopen()'ing a relocatable object
333	 * result in objects being loaded on rtld's link-map, make sure these
334	 * objects are initialized also.
335	 */
336	if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init)
337		load_completion(nlmp);
338
339	/*
340	 * Make sure the object to which we've bound has had it's .init fired.
341	 * Cleanup before return to user code.
342	 */
343	if (entry) {
344		is_dep_init(nlmp, lmp);
345		leave(lml, 0);
346	}
347
348	if (lmflags & LML_FLG_RTLDLM)
349		dbg_desc->d_class = dbg_class;
350
351	return (symval);
352}
353
354/*
355 * Read and process the relocations for one link object, we assume all
356 * relocation sections for loadable segments are stored contiguously in
357 * the file.
358 */
359int
360elf_reloc(Rt_map *lmp, uint_t plt, int *in_nfavl, APlist **textrel)
361{
362	ulong_t		relbgn, relend, relsiz, basebgn, pltbgn, pltend;
363	ulong_t		_pltbgn, _pltend;
364	ulong_t		dsymndx, roffset, rsymndx, psymndx = 0;
365	uchar_t		rtype;
366	long		value, pvalue;
367	Sym		*symref, *psymref, *symdef, *psymdef;
368	char		*name, *pname;
369	Rt_map		*_lmp, *plmp;
370	int		ret = 1, noplt = 0;
371	int		relacount = RELACOUNT(lmp), plthint = 0;
372	Rel		*rel;
373	uint_t		binfo, pbinfo;
374	APlist		*bound = NULL;
375
376	/*
377	 * Although only necessary for lazy binding, initialize the first
378	 * global offset entry to go to elf_rtbndr().  dbx(1) seems
379	 * to find this useful.
380	 */
381	if ((plt == 0) && PLTGOT(lmp)) {
382		mmapobj_result_t	*mpp;
383
384		/*
385		 * Make sure the segment is writable.
386		 */
387		if ((((mpp =
388		    find_segment((caddr_t)PLTGOT(lmp), lmp)) != NULL) &&
389		    ((mpp->mr_prot & PROT_WRITE) == 0)) &&
390		    ((set_prot(lmp, mpp, 1) == 0) ||
391		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL)))
392			return (0);
393
394		elf_plt_init(PLTGOT(lmp), (caddr_t)lmp);
395	}
396
397	/*
398	 * Initialize the plt start and end addresses.
399	 */
400	if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0)
401		pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp));
402
403	relsiz = (ulong_t)(RELENT(lmp));
404	basebgn = ADDR(lmp);
405
406	if (PLTRELSZ(lmp))
407		plthint = PLTRELSZ(lmp) / relsiz;
408
409	/*
410	 * If we've been called upon to promote an RTLD_LAZY object to an
411	 * RTLD_NOW then we're only interested in scaning the .plt table.
412	 * An uninitialized .plt is the case where the associated got entry
413	 * points back to the plt itself.  Determine the range of the real .plt
414	 * entries using the _PROCEDURE_LINKAGE_TABLE_ symbol.
415	 */
416	if (plt) {
417		Slookup	sl;
418		Sresult	sr;
419
420		relbgn = pltbgn;
421		relend = pltend;
422		if (!relbgn || (relbgn == relend))
423			return (1);
424
425		/*
426		 * Initialize the symbol lookup, and symbol result, data
427		 * structures.
428		 */
429		SLOOKUP_INIT(sl, MSG_ORIG(MSG_SYM_PLT), lmp, lmp, ld_entry_cnt,
430		    elf_hash(MSG_ORIG(MSG_SYM_PLT)), 0, 0, 0, LKUP_DEFT);
431		SRESULT_INIT(sr, MSG_ORIG(MSG_SYM_PLT));
432
433		if (elf_find_sym(&sl, &sr, &binfo, NULL) == 0)
434			return (1);
435
436		symdef = sr.sr_sym;
437		_pltbgn = symdef->st_value;
438		if (!(FLAGS(lmp) & FLG_RT_FIXED) &&
439		    (symdef->st_shndx != SHN_ABS))
440			_pltbgn += basebgn;
441		_pltend = _pltbgn + (((PLTRELSZ(lmp) / relsiz)) *
442		    M_PLT_ENTSIZE) + M_PLT_RESERVSZ;
443
444	} else {
445		/*
446		 * The relocation sections appear to the run-time linker as a
447		 * single table.  Determine the address of the beginning and end
448		 * of this table.  There are two different interpretations of
449		 * the ABI at this point:
450		 *
451		 *   o	The REL table and its associated RELSZ indicate the
452		 *	concatenation of *all* relocation sections (this is the
453		 *	model our link-editor constructs).
454		 *
455		 *   o	The REL table and its associated RELSZ indicate the
456		 *	concatenation of all *but* the .plt relocations.  These
457		 *	relocations are specified individually by the JMPREL and
458		 *	PLTRELSZ entries.
459		 *
460		 * Determine from our knowledege of the relocation range and
461		 * .plt range, the range of the total relocation table.  Note
462		 * that one other ABI assumption seems to be that the .plt
463		 * relocations always follow any other relocations, the
464		 * following range checking drops that assumption.
465		 */
466		relbgn = (ulong_t)(REL(lmp));
467		relend = relbgn + (ulong_t)(RELSZ(lmp));
468		if (pltbgn) {
469			if (!relbgn || (relbgn > pltbgn))
470				relbgn = pltbgn;
471			if (!relbgn || (relend < pltend))
472				relend = pltend;
473		}
474	}
475	if (!relbgn || (relbgn == relend)) {
476		DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE));
477		return (1);
478	}
479	DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START));
480
481	/*
482	 * If we're processing a dynamic executable in lazy mode there is no
483	 * need to scan the .rel.plt table, however if we're processing a shared
484	 * object in lazy mode the .got addresses associated to each .plt must
485	 * be relocated to reflect the location of the shared object.
486	 */
487	if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0) &&
488	    (FLAGS(lmp) & FLG_RT_FIXED))
489		noplt = 1;
490
491	/*
492	 * Loop through relocations.
493	 */
494	while (relbgn < relend) {
495		mmapobj_result_t	*mpp;
496		uint_t			sb_flags = 0;
497
498		rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info, M_MACH);
499
500		/*
501		 * If this is a RELATIVE relocation in a shared object (the
502		 * common case), and if we are not debugging, then jump into a
503		 * tighter relocation loop (elf_reloc_relative).
504		 */
505		if ((rtype == R_386_RELATIVE) &&
506		    ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) {
507			if (relacount) {
508				relbgn = elf_reloc_relative_count(relbgn,
509				    relacount, relsiz, basebgn, lmp, textrel);
510				relacount = 0;
511			} else {
512				relbgn = elf_reloc_relative(relbgn, relend,
513				    relsiz, basebgn, lmp, textrel);
514			}
515			if (relbgn >= relend)
516				break;
517			rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info, M_MACH);
518		}
519
520		roffset = ((Rel *)relbgn)->r_offset;
521
522		/*
523		 * If this is a shared object, add the base address to offset.
524		 */
525		if (!(FLAGS(lmp) & FLG_RT_FIXED)) {
526			/*
527			 * If we're processing lazy bindings, we have to step
528			 * through the plt entries and add the base address
529			 * to the corresponding got entry.
530			 */
531			if (plthint && (plt == 0) &&
532			    (rtype == R_386_JMP_SLOT) &&
533			    ((MODE(lmp) & RTLD_NOW) == 0)) {
534				relbgn = elf_reloc_relative_count(relbgn,
535				    plthint, relsiz, basebgn, lmp, textrel);
536				plthint = 0;
537				continue;
538			}
539			roffset += basebgn;
540		}
541
542		rsymndx = ELF_R_SYM(((Rel *)relbgn)->r_info);
543		rel = (Rel *)relbgn;
544		relbgn += relsiz;
545
546		/*
547		 * Optimizations.
548		 */
549		if (rtype == R_386_NONE)
550			continue;
551		if (noplt && ((ulong_t)rel >= pltbgn) &&
552		    ((ulong_t)rel < pltend)) {
553			relbgn = pltend;
554			continue;
555		}
556
557		/*
558		 * If we're promoting plts, determine if this one has already
559		 * been written.
560		 */
561		if (plt && ((*(ulong_t *)roffset < _pltbgn) ||
562		    (*(ulong_t *)roffset > _pltend)))
563			continue;
564
565		/*
566		 * If this relocation is not against part of the image
567		 * mapped into memory we skip it.
568		 */
569		if ((mpp = find_segment((caddr_t)roffset, lmp)) == NULL) {
570			elf_reloc_bad(lmp, (void *)rel, rtype, roffset,
571			    rsymndx);
572			continue;
573		}
574
575		binfo = 0;
576		/*
577		 * If a symbol index is specified then get the symbol table
578		 * entry, locate the symbol definition, and determine its
579		 * address.
580		 */
581		if (rsymndx) {
582			/*
583			 * Get the local symbol table entry.
584			 */
585			symref = (Sym *)((ulong_t)SYMTAB(lmp) +
586			    (rsymndx * SYMENT(lmp)));
587
588			/*
589			 * If this is a local symbol, just use the base address.
590			 * (we should have no local relocations in the
591			 * executable).
592			 */
593			if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) {
594				value = basebgn;
595				name = NULL;
596
597				/*
598				 * Special case TLS relocations.
599				 */
600				if (rtype == R_386_TLS_DTPMOD32) {
601					/*
602					 * Use the TLS modid.
603					 */
604					value = TLSMODID(lmp);
605
606				} else if (rtype == R_386_TLS_TPOFF) {
607					if ((value = elf_static_tls(lmp, symref,
608					    rel, rtype, 0, roffset, 0)) == 0) {
609						ret = 0;
610						break;
611					}
612				}
613			} else {
614				/*
615				 * If the symbol index is equal to the previous
616				 * symbol index relocation we processed then
617				 * reuse the previous values. (Note that there
618				 * have been cases where a relocation exists
619				 * against a copy relocation symbol, our ld(1)
620				 * should optimize this away, but make sure we
621				 * don't use the same symbol information should
622				 * this case exist).
623				 */
624				if ((rsymndx == psymndx) &&
625				    (rtype != R_386_COPY)) {
626					/* LINTED */
627					if (psymdef == 0) {
628						DBG_CALL(Dbg_bind_weak(lmp,
629						    (Addr)roffset, (Addr)
630						    (roffset - basebgn), name));
631						continue;
632					}
633					/* LINTED */
634					value = pvalue;
635					/* LINTED */
636					name = pname;
637					/* LINTED */
638					symdef = psymdef;
639					/* LINTED */
640					symref = psymref;
641					/* LINTED */
642					_lmp = plmp;
643					/* LINTED */
644					binfo = pbinfo;
645
646					if ((LIST(_lmp)->lm_tflags |
647					    AFLAGS(_lmp)) &
648					    LML_TFLG_AUD_SYMBIND) {
649						value = audit_symbind(lmp, _lmp,
650						    /* LINTED */
651						    symdef, dsymndx, value,
652						    &sb_flags);
653					}
654				} else {
655					Slookup		sl;
656					Sresult		sr;
657
658					/*
659					 * Lookup the symbol definition.
660					 * Initialize the symbol lookup, and
661					 * symbol result, data structures.
662					 */
663					name = (char *)(STRTAB(lmp) +
664					    symref->st_name);
665
666					SLOOKUP_INIT(sl, name, lmp, 0,
667					    ld_entry_cnt, 0, rsymndx, symref,
668					    rtype, LKUP_STDRELOC);
669					SRESULT_INIT(sr, name);
670					symdef = NULL;
671
672					if (lookup_sym(&sl, &sr, &binfo,
673					    in_nfavl)) {
674						name = (char *)sr.sr_name;
675						_lmp = sr.sr_dmap;
676						symdef = sr.sr_sym;
677					}
678
679					/*
680					 * If the symbol is not found and the
681					 * reference was not to a weak symbol,
682					 * report an error.  Weak references
683					 * may be unresolved.
684					 */
685					/* BEGIN CSTYLED */
686					if (symdef == 0) {
687					    if (sl.sl_bind != STB_WEAK) {
688						if (elf_reloc_error(lmp, name,
689						    rel, binfo))
690							continue;
691
692					   	ret = 0;
693						break;
694
695					    } else {
696						psymndx = rsymndx;
697						psymdef = 0;
698
699						DBG_CALL(Dbg_bind_weak(lmp,
700						    (Addr)roffset, (Addr)
701						    (roffset - basebgn), name));
702						continue;
703					    }
704					}
705					/* END CSTYLED */
706
707					/*
708					 * If symbol was found in an object
709					 * other than the referencing object
710					 * then record the binding.
711					 */
712					if ((lmp != _lmp) && ((FLAGS1(_lmp) &
713					    FL1_RT_NOINIFIN) == 0)) {
714						if (aplist_test(&bound, _lmp,
715						    AL_CNT_RELBIND) == 0) {
716							ret = 0;
717							break;
718						}
719					}
720
721					/*
722					 * Calculate the location of definition;
723					 * symbol value plus base address of
724					 * containing shared object.
725					 */
726					if (IS_SIZE(rtype))
727						value = symdef->st_size;
728					else
729						value = symdef->st_value;
730
731					if (!(FLAGS(_lmp) & FLG_RT_FIXED) &&
732					    !(IS_SIZE(rtype)) &&
733					    (symdef->st_shndx != SHN_ABS) &&
734					    (ELF_ST_TYPE(symdef->st_info) !=
735					    STT_TLS))
736						value += ADDR(_lmp);
737
738					/*
739					 * Retain this symbol index and the
740					 * value in case it can be used for the
741					 * subsequent relocations.
742					 */
743					if (rtype != R_386_COPY) {
744						psymndx = rsymndx;
745						pvalue = value;
746						pname = name;
747						psymdef = symdef;
748						psymref = symref;
749						plmp = _lmp;
750						pbinfo = binfo;
751					}
752					if ((LIST(_lmp)->lm_tflags |
753					    AFLAGS(_lmp)) &
754					    LML_TFLG_AUD_SYMBIND) {
755						dsymndx = (((uintptr_t)symdef -
756						    (uintptr_t)SYMTAB(_lmp)) /
757						    SYMENT(_lmp));
758						value = audit_symbind(lmp, _lmp,
759						    symdef, dsymndx, value,
760						    &sb_flags);
761					}
762				}
763
764				/*
765				 * If relocation is PC-relative, subtract
766				 * offset address.
767				 */
768				if (IS_PC_RELATIVE(rtype))
769					value -= roffset;
770
771				/*
772				 * Special case TLS relocations.
773				 */
774				if (rtype == R_386_TLS_DTPMOD32) {
775					/*
776					 * Relocation value is the TLS modid.
777					 */
778					value = TLSMODID(_lmp);
779
780				} else if (rtype == R_386_TLS_TPOFF) {
781					if ((value = elf_static_tls(_lmp,
782					    symdef, rel, rtype, name, roffset,
783					    value)) == 0) {
784						ret = 0;
785						break;
786					}
787				}
788			}
789		} else {
790			/*
791			 * Special cases.
792			 */
793			if (rtype == R_386_TLS_DTPMOD32) {
794				/*
795				 * TLS relocation value is the TLS modid.
796				 */
797				value = TLSMODID(lmp);
798			} else
799				value = basebgn;
800
801			name = NULL;
802		}
803
804		DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH,
805		    M_REL_SHT_TYPE, rel, NULL, 0, name));
806
807		/*
808		 * Make sure the segment is writable.
809		 */
810		if (((mpp->mr_prot & PROT_WRITE) == 0) &&
811		    ((set_prot(lmp, mpp, 1) == 0) ||
812		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) {
813			ret = 0;
814			break;
815		}
816
817		/*
818		 * Call relocation routine to perform required relocation.
819		 */
820		switch (rtype) {
821		case R_386_COPY:
822			if (elf_copy_reloc(name, symref, lmp, (void *)roffset,
823			    symdef, _lmp, (const void *)value) == 0)
824				ret = 0;
825			break;
826		case R_386_JMP_SLOT:
827			if (((LIST(lmp)->lm_tflags | AFLAGS(lmp)) &
828			    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
829			    AUDINFO(lmp)->ai_dynplts) {
830				int	fail = 0;
831				int	pltndx = (((ulong_t)rel -
832				    (uintptr_t)JMPREL(lmp)) / relsiz);
833				int	symndx = (((uintptr_t)symdef -
834				    (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp));
835
836				(void) elf_plt_trace_write(roffset, lmp, _lmp,
837				    symdef, symndx, pltndx, (caddr_t)value,
838				    sb_flags, &fail);
839				if (fail)
840					ret = 0;
841			} else {
842				/*
843				 * Write standard PLT entry to jump directly
844				 * to newly bound function.
845				 */
846				DBG_CALL(Dbg_reloc_apply_val(LIST(lmp),
847				    ELF_DBG_RTLD, (Xword)roffset,
848				    (Xword)value));
849				*(ulong_t *)roffset = value;
850			}
851			break;
852		default:
853			/*
854			 * Write the relocation out.
855			 */
856			if (do_reloc_rtld(rtype, (uchar_t *)roffset,
857			    (Word *)&value, name, NAME(lmp), LIST(lmp)) == 0)
858				ret = 0;
859
860			DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD,
861			    (Xword)roffset, (Xword)value));
862		}
863
864		if ((ret == 0) &&
865		    ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0))
866			break;
867
868		if (binfo) {
869			DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset,
870			    (Off)(roffset - basebgn), (Xword)(-1), PLT_T_FULL,
871			    _lmp, (Addr)value, symdef->st_value, name, binfo));
872		}
873	}
874
875	return (relocate_finish(lmp, bound, ret));
876}
877
878/*
879 * Initialize the first few got entries so that function calls go to
880 * elf_rtbndr:
881 *
882 *	GOT[GOT_XLINKMAP] =	the address of the link map
883 *	GOT[GOT_XRTLD] =	the address of rtbinder
884 */
885void
886elf_plt_init(void *got, caddr_t l)
887{
888	uint_t		*_got;
889	/* LINTED */
890	Rt_map		*lmp = (Rt_map *)l;
891
892	_got = (uint_t *)got + M_GOT_XLINKMAP;
893	*_got = (uint_t)lmp;
894	_got = (uint_t *)got + M_GOT_XRTLD;
895	*_got = (uint_t)elf_rtbndr;
896}
897
898/*
899 * For SVR4 Intel compatability.  USL uses /usr/lib/libc.so.1 as the run-time
900 * linker, so the interpreter's address will differ from /usr/lib/ld.so.1.
901 * Further, USL has special _iob[] and _ctype[] processing that makes up for the
902 * fact that these arrays do not have associated copy relocations.  So we try
903 * and make up for that here.  Any relocations found will be added to the global
904 * copy relocation list and will be processed in setup().
905 */
906static int
907_elf_copy_reloc(const char *name, Rt_map *rlmp, Rt_map *dlmp)
908{
909	Sym		*symref, *symdef;
910	caddr_t 	ref, def;
911	Rt_map		*_lmp;
912	Rel		rel;
913	Slookup		sl;
914	Sresult		sr;
915	uint_t		binfo;
916
917	/*
918	 * Determine if the special symbol exists as a reference in the dynamic
919	 * executable, and that an associated definition exists in libc.so.1.
920	 *
921	 * Initialize the symbol lookup, and symbol result, data structures.
922	 */
923	SLOOKUP_INIT(sl, name, rlmp, rlmp, ld_entry_cnt, 0, 0, 0, 0,
924	    LKUP_FIRST);
925	SRESULT_INIT(sr, name);
926
927	if (lookup_sym(&sl, &sr, &binfo, NULL) == 0)
928		return (1);
929	symref = sr.sr_sym;
930
931	SLOOKUP_INIT(sl, name, rlmp, dlmp, ld_entry_cnt, 0, 0, 0, 0,
932	    LKUP_DEFT);
933	SRESULT_INIT(sr, name);
934
935	if (lookup_sym(&sl, &sr, &binfo, NULL) == 0)
936		return (1);
937
938	_lmp = sr.sr_dmap;
939	symdef = sr.sr_sym;
940
941	if (strcmp(NAME(sr.sr_dmap), MSG_ORIG(MSG_PTH_LIBC)))
942		return (1);
943
944	/*
945	 * Determine the reference and definition addresses.
946	 */
947	ref = (void *)(symref->st_value);
948	if (!(FLAGS(rlmp) & FLG_RT_FIXED))
949		ref += ADDR(rlmp);
950	def = (void *)(symdef->st_value);
951	if (!(FLAGS(sr.sr_dmap) & FLG_RT_FIXED))
952		def += ADDR(_lmp);
953
954	/*
955	 * Set up a relocation entry for debugging and call the generic copy
956	 * relocation function to provide symbol size error checking and to
957	 * record the copy relocation that must be performed.
958	 */
959	rel.r_offset = (Addr)ref;
960	rel.r_info = (Word)R_386_COPY;
961	DBG_CALL(Dbg_reloc_in(LIST(rlmp), ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE,
962	    &rel, NULL, 0, name));
963
964	return (elf_copy_reloc((char *)name, symref, rlmp, (void *)ref, symdef,
965	    _lmp, (void *)def));
966}
967
968int
969elf_copy_gen(Rt_map *lmp)
970{
971	if (interp && ((ulong_t)interp->i_faddr !=
972	    r_debug.rtd_rdebug.r_ldbase) &&
973	    !(strcmp(interp->i_name, MSG_ORIG(MSG_PTH_LIBC)))) {
974
975		DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, 0,
976		    DBG_REL_START));
977
978		if (_elf_copy_reloc(MSG_ORIG(MSG_SYM_CTYPE), lmp,
979		    (Rt_map *)NEXT(lmp)) == 0)
980			return (0);
981		if (_elf_copy_reloc(MSG_ORIG(MSG_SYM_IOB), lmp,
982		    (Rt_map *)NEXT(lmp)) == 0)
983			return (0);
984	}
985	return (1);
986}
987
988/*
989 * Plt writing interface to allow debugging initialization to be generic.
990 */
991Pltbindtype
992/* ARGSUSED1 */
993elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval,
994	Xword pltndx)
995{
996	Rel		*rel = (Rel*)rptr;
997	uintptr_t	pltaddr;
998
999	pltaddr = addr + rel->r_offset;
1000	*(ulong_t *)pltaddr = (ulong_t)symval;
1001	DBG_CALL(pltcntfull++);
1002	return (PLT_T_FULL);
1003}
1004
1005/*
1006 * Provide a machine specific interface to the conversion routine.  By calling
1007 * the machine specific version, rather than the generic version, we insure that
1008 * the data tables/strings for all known machine versions aren't dragged into
1009 * ld.so.1.
1010 */
1011const char *
1012_conv_reloc_type(uint_t rel)
1013{
1014	static Conv_inv_buf_t	inv_buf;
1015
1016	return (conv_reloc_386_type(rel, 0, &inv_buf));
1017}
1018