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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 
     22 /*
     23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
     24  * Use is subject to license terms.
     25  */
     26 
     27 /*
     28  *	Copyright (c) 1988 AT&T
     29  *	  All Rights Reserved
     30  */
     31 
     32 /*
     33  * 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 
     53 extern void	elf_rtbndr(Rt_map *, ulong_t, caddr_t);
     54 
     55 int
     56 elf_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 
     69 void
     70 ldso_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 
     82 static 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 };
     88 int	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  */
    105 static caddr_t
    106 elf_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  */
    193 ulong_t
    194 elf_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 	int		entry, lmflags;
    204 	Lm_list		*lml;
    205 
    206 	/*
    207 	 * For compatibility with libthread (TI_VERSION 1) we track the entry
    208 	 * value.  A zero value indicates we have recursed into ld.so.1 to
    209 	 * further process a locking request.  Under this recursion we disable
    210 	 * tsort and cleanup activities.
    211 	 */
    212 	entry = enter(0);
    213 
    214 	lml = LIST(lmp);
    215 	if ((lmflags = lml->lm_flags) & LML_FLG_RTLDLM) {
    216 		dbg_class = dbg_desc->d_class;
    217 		dbg_desc->d_class = 0;
    218 	}
    219 
    220 	/*
    221 	 * Perform some basic sanity checks.  If we didn't get a load map or
    222 	 * the relocation offset is invalid then its possible someone has walked
    223 	 * over the .got entries or jumped to plt0 out of the blue.
    224 	 */
    225 	if (!lmp || ((reloff % sizeof (Rel)) != 0)) {
    226 		Conv_inv_buf_t inv_buf;
    227 
    228 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_PLTREF),
    229 		    conv_reloc_386_type(R_386_JMP_SLOT, 0, &inv_buf),
    230 		    EC_NATPTR(lmp), EC_XWORD(reloff), EC_NATPTR(from));
    231 		rtldexit(lml, 1);
    232 	}
    233 
    234 	/*
    235 	 * Use relocation entry to get symbol table entry and symbol name.
    236 	 */
    237 	addr = (ulong_t)JMPREL(lmp);
    238 	rptr = (Rel *)(addr + reloff);
    239 	rsymndx = ELF_R_SYM(rptr->r_info);
    240 	rsym = (Sym *)((ulong_t)SYMTAB(lmp) + (rsymndx * SYMENT(lmp)));
    241 	name = (char *)(STRTAB(lmp) + rsym->st_name);
    242 
    243 	/*
    244 	 * Determine the last link-map of this list, this'll be the starting
    245 	 * point for any tsort() processing.
    246 	 */
    247 	llmp = lml->lm_tail;
    248 
    249 	/*
    250 	 * Find definition for symbol.  Initialize the symbol lookup data
    251 	 * structure.
    252 	 */
    253 	SLOOKUP_INIT(sl, name, lmp, lml->lm_head, ld_entry_cnt, 0,
    254 	    rsymndx, rsym, 0, LKUP_DEFT);
    255 
    256 	if ((nsym = lookup_sym(&sl, &nlmp, &binfo, NULL)) == 0) {
    257 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_REL_NOSYM), NAME(lmp),
    258 		    demangle(name));
    259 		rtldexit(lml, 1);
    260 	}
    261 
    262 	symval = nsym->st_value;
    263 	if (!(FLAGS(nlmp) & FLG_RT_FIXED) &&
    264 	    (nsym->st_shndx != SHN_ABS))
    265 		symval += ADDR(nlmp);
    266 	if ((lmp != nlmp) && ((FLAGS1(nlmp) & FL1_RT_NOINIFIN) == 0)) {
    267 		/*
    268 		 * Record that this new link map is now bound to the caller.
    269 		 */
    270 		if (bind_one(lmp, nlmp, BND_REFER) == 0)
    271 			rtldexit(lml, 1);
    272 	}
    273 
    274 	if ((lml->lm_tflags | AFLAGS(lmp)) & LML_TFLG_AUD_SYMBIND) {
    275 		uint_t	symndx = (((uintptr_t)nsym -
    276 		    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
    277 		symval = audit_symbind(lmp, nlmp, nsym, symndx, symval,
    278 		    &sb_flags);
    279 	}
    280 
    281 	if (!(rtld_flags & RT_FL_NOBIND)) {
    282 		addr = rptr->r_offset;
    283 		if (!(FLAGS(lmp) & FLG_RT_FIXED))
    284 			addr += ADDR(lmp);
    285 		if (((lml->lm_tflags | AFLAGS(lmp)) &
    286 		    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
    287 		    AUDINFO(lmp)->ai_dynplts) {
    288 			int	fail = 0;
    289 			uint_t	pltndx = reloff / sizeof (Rel);
    290 			uint_t	symndx = (((uintptr_t)nsym -
    291 			    (uintptr_t)SYMTAB(nlmp)) / SYMENT(nlmp));
    292 
    293 			symval = (ulong_t)elf_plt_trace_write(addr, lmp, nlmp,
    294 			    nsym, symndx, pltndx, (caddr_t)symval, sb_flags,
    295 			    &fail);
    296 			if (fail)
    297 				rtldexit(lml, 1);
    298 		} else {
    299 			/*
    300 			 * Write standard PLT entry to jump directly
    301 			 * to newly bound function.
    302 			 */
    303 			*(ulong_t *)addr = symval;
    304 		}
    305 	}
    306 
    307 	/*
    308 	 * Print binding information and rebuild PLT entry.
    309 	 */
    310 	DBG_CALL(Dbg_bind_global(lmp, (Addr)from, (Off)(from - ADDR(lmp)),
    311 	    (Xword)(reloff / sizeof (Rel)), PLT_T_FULL, nlmp, (Addr)symval,
    312 	    nsym->st_value, name, binfo));
    313 
    314 	/*
    315 	 * Complete any processing for newly loaded objects.  Note we don't
    316 	 * know exactly where any new objects are loaded (we know the object
    317 	 * that supplied the symbol, but others may have been loaded lazily as
    318 	 * we searched for the symbol), so sorting starts from the last
    319 	 * link-map know on entry to this routine.
    320 	 */
    321 	if (entry)
    322 		load_completion(llmp);
    323 
    324 	/*
    325 	 * Some operations like dldump() or dlopen()'ing a relocatable object
    326 	 * result in objects being loaded on rtld's link-map, make sure these
    327 	 * objects are initialized also.
    328 	 */
    329 	if ((LIST(nlmp)->lm_flags & LML_FLG_RTLDLM) && LIST(nlmp)->lm_init)
    330 		load_completion(nlmp);
    331 
    332 	/*
    333 	 * Make sure the object to which we've bound has had it's .init fired.
    334 	 * Cleanup before return to user code.
    335 	 */
    336 	if (entry) {
    337 		is_dep_init(nlmp, lmp);
    338 		leave(lml, 0);
    339 	}
    340 
    341 	if (lmflags & LML_FLG_RTLDLM)
    342 		dbg_desc->d_class = dbg_class;
    343 
    344 	return (symval);
    345 }
    346 
    347 /*
    348  * Read and process the relocations for one link object, we assume all
    349  * relocation sections for loadable segments are stored contiguously in
    350  * the file.
    351  */
    352 int
    353 elf_reloc(Rt_map *lmp, uint_t plt, int *in_nfavl, APlist **textrel)
    354 {
    355 	ulong_t		relbgn, relend, relsiz, basebgn, pltbgn, pltend;
    356 	ulong_t		_pltbgn, _pltend;
    357 	ulong_t		dsymndx, roffset, rsymndx, psymndx = 0;
    358 	uchar_t		rtype;
    359 	long		value, pvalue;
    360 	Sym		*symref, *psymref, *symdef, *psymdef;
    361 	char		*name, *pname;
    362 	Rt_map		*_lmp, *plmp;
    363 	int		ret = 1, noplt = 0;
    364 	int		relacount = RELACOUNT(lmp), plthint = 0;
    365 	Rel		*rel;
    366 	uint_t		binfo, pbinfo;
    367 	APlist		*bound = NULL;
    368 
    369 	/*
    370 	 * Although only necessary for lazy binding, initialize the first
    371 	 * global offset entry to go to elf_rtbndr().  dbx(1) seems
    372 	 * to find this useful.
    373 	 */
    374 	if ((plt == 0) && PLTGOT(lmp)) {
    375 		mmapobj_result_t	*mpp;
    376 
    377 		/*
    378 		 * Make sure the segment is writable.
    379 		 */
    380 		if ((((mpp =
    381 		    find_segment((caddr_t)PLTGOT(lmp), lmp)) != NULL) &&
    382 		    ((mpp->mr_prot & PROT_WRITE) == 0)) &&
    383 		    ((set_prot(lmp, mpp, 1) == 0) ||
    384 		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL)))
    385 			return (0);
    386 
    387 		elf_plt_init(PLTGOT(lmp), (caddr_t)lmp);
    388 	}
    389 
    390 	/*
    391 	 * Initialize the plt start and end addresses.
    392 	 */
    393 	if ((pltbgn = (ulong_t)JMPREL(lmp)) != 0)
    394 		pltend = pltbgn + (ulong_t)(PLTRELSZ(lmp));
    395 
    396 	relsiz = (ulong_t)(RELENT(lmp));
    397 	basebgn = ADDR(lmp);
    398 
    399 	if (PLTRELSZ(lmp))
    400 		plthint = PLTRELSZ(lmp) / relsiz;
    401 
    402 	/*
    403 	 * If we've been called upon to promote an RTLD_LAZY object to an
    404 	 * RTLD_NOW then we're only interested in scaning the .plt table.
    405 	 * An uninitialized .plt is the case where the associated got entry
    406 	 * points back to the plt itself.  Determine the range of the real .plt
    407 	 * entries using the _PROCEDURE_LINKAGE_TABLE_ symbol.
    408 	 */
    409 	if (plt) {
    410 		Slookup	sl;
    411 
    412 		relbgn = pltbgn;
    413 		relend = pltend;
    414 		if (!relbgn || (relbgn == relend))
    415 			return (1);
    416 
    417 		/*
    418 		 * Initialize the symbol lookup data structure.
    419 		 */
    420 		SLOOKUP_INIT(sl, MSG_ORIG(MSG_SYM_PLT), lmp, lmp, ld_entry_cnt,
    421 		    elf_hash(MSG_ORIG(MSG_SYM_PLT)), 0, 0, 0, LKUP_DEFT);
    422 
    423 		if ((symdef = elf_find_sym(&sl, &_lmp, &binfo, NULL)) == 0)
    424 			return (1);
    425 
    426 		_pltbgn = symdef->st_value;
    427 		if (!(FLAGS(lmp) & FLG_RT_FIXED) &&
    428 		    (symdef->st_shndx != SHN_ABS))
    429 			_pltbgn += basebgn;
    430 		_pltend = _pltbgn + (((PLTRELSZ(lmp) / relsiz)) *
    431 		    M_PLT_ENTSIZE) + M_PLT_RESERVSZ;
    432 
    433 	} else {
    434 		/*
    435 		 * The relocation sections appear to the run-time linker as a
    436 		 * single table.  Determine the address of the beginning and end
    437 		 * of this table.  There are two different interpretations of
    438 		 * the ABI at this point:
    439 		 *
    440 		 *   o	The REL table and its associated RELSZ indicate the
    441 		 *	concatenation of *all* relocation sections (this is the
    442 		 *	model our link-editor constructs).
    443 		 *
    444 		 *   o	The REL table and its associated RELSZ indicate the
    445 		 *	concatenation of all *but* the .plt relocations.  These
    446 		 *	relocations are specified individually by the JMPREL and
    447 		 *	PLTRELSZ entries.
    448 		 *
    449 		 * Determine from our knowledege of the relocation range and
    450 		 * .plt range, the range of the total relocation table.  Note
    451 		 * that one other ABI assumption seems to be that the .plt
    452 		 * relocations always follow any other relocations, the
    453 		 * following range checking drops that assumption.
    454 		 */
    455 		relbgn = (ulong_t)(REL(lmp));
    456 		relend = relbgn + (ulong_t)(RELSZ(lmp));
    457 		if (pltbgn) {
    458 			if (!relbgn || (relbgn > pltbgn))
    459 				relbgn = pltbgn;
    460 			if (!relbgn || (relend < pltend))
    461 				relend = pltend;
    462 		}
    463 	}
    464 	if (!relbgn || (relbgn == relend)) {
    465 		DBG_CALL(Dbg_reloc_run(lmp, 0, plt, DBG_REL_NONE));
    466 		return (1);
    467 	}
    468 	DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, plt, DBG_REL_START));
    469 
    470 	/*
    471 	 * If we're processing a dynamic executable in lazy mode there is no
    472 	 * need to scan the .rel.plt table, however if we're processing a shared
    473 	 * object in lazy mode the .got addresses associated to each .plt must
    474 	 * be relocated to reflect the location of the shared object.
    475 	 */
    476 	if (pltbgn && ((MODE(lmp) & RTLD_NOW) == 0) &&
    477 	    (FLAGS(lmp) & FLG_RT_FIXED))
    478 		noplt = 1;
    479 
    480 	/*
    481 	 * Loop through relocations.
    482 	 */
    483 	while (relbgn < relend) {
    484 		mmapobj_result_t	*mpp;
    485 		uint_t			sb_flags = 0;
    486 
    487 		rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info, M_MACH);
    488 
    489 		/*
    490 		 * If this is a RELATIVE relocation in a shared object (the
    491 		 * common case), and if we are not debugging, then jump into a
    492 		 * tighter relocation loop (elf_reloc_relative).
    493 		 */
    494 		if ((rtype == R_386_RELATIVE) &&
    495 		    ((FLAGS(lmp) & FLG_RT_FIXED) == 0) && (DBG_ENABLED == 0)) {
    496 			if (relacount) {
    497 				relbgn = elf_reloc_relative_count(relbgn,
    498 				    relacount, relsiz, basebgn, lmp, textrel);
    499 				relacount = 0;
    500 			} else {
    501 				relbgn = elf_reloc_relative(relbgn, relend,
    502 				    relsiz, basebgn, lmp, textrel);
    503 			}
    504 			if (relbgn >= relend)
    505 				break;
    506 			rtype = ELF_R_TYPE(((Rel *)relbgn)->r_info, M_MACH);
    507 		}
    508 
    509 		roffset = ((Rel *)relbgn)->r_offset;
    510 
    511 		/*
    512 		 * If this is a shared object, add the base address to offset.
    513 		 */
    514 		if (!(FLAGS(lmp) & FLG_RT_FIXED)) {
    515 			/*
    516 			 * If we're processing lazy bindings, we have to step
    517 			 * through the plt entries and add the base address
    518 			 * to the corresponding got entry.
    519 			 */
    520 			if (plthint && (plt == 0) &&
    521 			    (rtype == R_386_JMP_SLOT) &&
    522 			    ((MODE(lmp) & RTLD_NOW) == 0)) {
    523 				relbgn = elf_reloc_relative_count(relbgn,
    524 				    plthint, relsiz, basebgn, lmp, textrel);
    525 				plthint = 0;
    526 				continue;
    527 			}
    528 			roffset += basebgn;
    529 		}
    530 
    531 		rsymndx = ELF_R_SYM(((Rel *)relbgn)->r_info);
    532 		rel = (Rel *)relbgn;
    533 		relbgn += relsiz;
    534 
    535 		/*
    536 		 * Optimizations.
    537 		 */
    538 		if (rtype == R_386_NONE)
    539 			continue;
    540 		if (noplt && ((ulong_t)rel >= pltbgn) &&
    541 		    ((ulong_t)rel < pltend)) {
    542 			relbgn = pltend;
    543 			continue;
    544 		}
    545 
    546 		/*
    547 		 * If we're promoting plts, determine if this one has already
    548 		 * been written.
    549 		 */
    550 		if (plt && ((*(ulong_t *)roffset < _pltbgn) ||
    551 		    (*(ulong_t *)roffset > _pltend)))
    552 			continue;
    553 
    554 		/*
    555 		 * If this relocation is not against part of the image
    556 		 * mapped into memory we skip it.
    557 		 */
    558 		if ((mpp = find_segment((caddr_t)roffset, lmp)) == NULL) {
    559 			elf_reloc_bad(lmp, (void *)rel, rtype, roffset,
    560 			    rsymndx);
    561 			continue;
    562 		}
    563 
    564 		binfo = 0;
    565 		/*
    566 		 * If a symbol index is specified then get the symbol table
    567 		 * entry, locate the symbol definition, and determine its
    568 		 * address.
    569 		 */
    570 		if (rsymndx) {
    571 			/*
    572 			 * Get the local symbol table entry.
    573 			 */
    574 			symref = (Sym *)((ulong_t)SYMTAB(lmp) +
    575 			    (rsymndx * SYMENT(lmp)));
    576 
    577 			/*
    578 			 * If this is a local symbol, just use the base address.
    579 			 * (we should have no local relocations in the
    580 			 * executable).
    581 			 */
    582 			if (ELF_ST_BIND(symref->st_info) == STB_LOCAL) {
    583 				value = basebgn;
    584 				name = (char *)0;
    585 
    586 				/*
    587 				 * Special case TLS relocations.
    588 				 */
    589 				if (rtype == R_386_TLS_DTPMOD32) {
    590 					/*
    591 					 * Use the TLS modid.
    592 					 */
    593 					value = TLSMODID(lmp);
    594 
    595 				} else if (rtype == R_386_TLS_TPOFF) {
    596 					if ((value = elf_static_tls(lmp, symref,
    597 					    rel, rtype, 0, roffset, 0)) == 0) {
    598 						ret = 0;
    599 						break;
    600 					}
    601 				}
    602 			} else {
    603 				/*
    604 				 * If the symbol index is equal to the previous
    605 				 * symbol index relocation we processed then
    606 				 * reuse the previous values. (Note that there
    607 				 * have been cases where a relocation exists
    608 				 * against a copy relocation symbol, our ld(1)
    609 				 * should optimize this away, but make sure we
    610 				 * don't use the same symbol information should
    611 				 * this case exist).
    612 				 */
    613 				if ((rsymndx == psymndx) &&
    614 				    (rtype != R_386_COPY)) {
    615 					/* LINTED */
    616 					if (psymdef == 0) {
    617 						DBG_CALL(Dbg_bind_weak(lmp,
    618 						    (Addr)roffset, (Addr)
    619 						    (roffset - basebgn), name));
    620 						continue;
    621 					}
    622 					/* LINTED */
    623 					value = pvalue;
    624 					/* LINTED */
    625 					name = pname;
    626 					/* LINTED */
    627 					symdef = psymdef;
    628 					/* LINTED */
    629 					symref = psymref;
    630 					/* LINTED */
    631 					_lmp = plmp;
    632 					/* LINTED */
    633 					binfo = pbinfo;
    634 
    635 					if ((LIST(_lmp)->lm_tflags |
    636 					    AFLAGS(_lmp)) &
    637 					    LML_TFLG_AUD_SYMBIND) {
    638 						value = audit_symbind(lmp, _lmp,
    639 						    /* LINTED */
    640 						    symdef, dsymndx, value,
    641 						    &sb_flags);
    642 					}
    643 				} else {
    644 					Slookup		sl;
    645 
    646 					/*
    647 					 * Lookup the symbol definition.
    648 					 * Initialize the symbol lookup data
    649 					 * structure.
    650 					 */
    651 					name = (char *)(STRTAB(lmp) +
    652 					    symref->st_name);
    653 
    654 					SLOOKUP_INIT(sl, name, lmp, 0,
    655 					    ld_entry_cnt, 0, rsymndx, symref,
    656 					    rtype, LKUP_STDRELOC);
    657 
    658 					symdef = lookup_sym(&sl, &_lmp,
    659 					    &binfo, in_nfavl);
    660 
    661 					/*
    662 					 * If the symbol is not found and the
    663 					 * reference was not to a weak symbol,
    664 					 * report an error.  Weak references
    665 					 * may be unresolved.
    666 					 */
    667 					/* BEGIN CSTYLED */
    668 					if (symdef == 0) {
    669 					    if (sl.sl_bind != STB_WEAK) {
    670 						if (elf_reloc_error(lmp, name,
    671 						    rel, binfo))
    672 							continue;
    673 
    674 					   	ret = 0;
    675 						break;
    676 
    677 					    } else {
    678 						psymndx = rsymndx;
    679 						psymdef = 0;
    680 
    681 						DBG_CALL(Dbg_bind_weak(lmp,
    682 						    (Addr)roffset, (Addr)
    683 						    (roffset - basebgn), name));
    684 						continue;
    685 					    }
    686 					}
    687 					/* END CSTYLED */
    688 
    689 					/*
    690 					 * If symbol was found in an object
    691 					 * other than the referencing object
    692 					 * then record the binding.
    693 					 */
    694 					if ((lmp != _lmp) && ((FLAGS1(_lmp) &
    695 					    FL1_RT_NOINIFIN) == 0)) {
    696 						if (aplist_test(&bound, _lmp,
    697 						    AL_CNT_RELBIND) == 0) {
    698 							ret = 0;
    699 							break;
    700 						}
    701 					}
    702 
    703 					/*
    704 					 * Calculate the location of definition;
    705 					 * symbol value plus base address of
    706 					 * containing shared object.
    707 					 */
    708 					if (IS_SIZE(rtype))
    709 						value = symdef->st_size;
    710 					else
    711 						value = symdef->st_value;
    712 
    713 					if (!(FLAGS(_lmp) & FLG_RT_FIXED) &&
    714 					    !(IS_SIZE(rtype)) &&
    715 					    (symdef->st_shndx != SHN_ABS) &&
    716 					    (ELF_ST_TYPE(symdef->st_info) !=
    717 					    STT_TLS))
    718 						value += ADDR(_lmp);
    719 
    720 					/*
    721 					 * Retain this symbol index and the
    722 					 * value in case it can be used for the
    723 					 * subsequent relocations.
    724 					 */
    725 					if (rtype != R_386_COPY) {
    726 						psymndx = rsymndx;
    727 						pvalue = value;
    728 						pname = name;
    729 						psymdef = symdef;
    730 						psymref = symref;
    731 						plmp = _lmp;
    732 						pbinfo = binfo;
    733 					}
    734 					if ((LIST(_lmp)->lm_tflags |
    735 					    AFLAGS(_lmp)) &
    736 					    LML_TFLG_AUD_SYMBIND) {
    737 						dsymndx = (((uintptr_t)symdef -
    738 						    (uintptr_t)SYMTAB(_lmp)) /
    739 						    SYMENT(_lmp));
    740 						value = audit_symbind(lmp, _lmp,
    741 						    symdef, dsymndx, value,
    742 						    &sb_flags);
    743 					}
    744 				}
    745 
    746 				/*
    747 				 * If relocation is PC-relative, subtract
    748 				 * offset address.
    749 				 */
    750 				if (IS_PC_RELATIVE(rtype))
    751 					value -= roffset;
    752 
    753 				/*
    754 				 * Special case TLS relocations.
    755 				 */
    756 				if (rtype == R_386_TLS_DTPMOD32) {
    757 					/*
    758 					 * Relocation value is the TLS modid.
    759 					 */
    760 					value = TLSMODID(_lmp);
    761 
    762 				} else if (rtype == R_386_TLS_TPOFF) {
    763 					if ((value = elf_static_tls(_lmp,
    764 					    symdef, rel, rtype, name, roffset,
    765 					    value)) == 0) {
    766 						ret = 0;
    767 						break;
    768 					}
    769 				}
    770 			}
    771 		} else {
    772 			/*
    773 			 * Special cases.
    774 			 */
    775 			if (rtype == R_386_TLS_DTPMOD32) {
    776 				/*
    777 				 * TLS relocation value is the TLS modid.
    778 				 */
    779 				value = TLSMODID(lmp);
    780 			} else
    781 				value = basebgn;
    782 			name = (char *)0;
    783 		}
    784 
    785 		DBG_CALL(Dbg_reloc_in(LIST(lmp), ELF_DBG_RTLD, M_MACH,
    786 		    M_REL_SHT_TYPE, rel, NULL, 0, name));
    787 
    788 		/*
    789 		 * Make sure the segment is writable.
    790 		 */
    791 		if (((mpp->mr_prot & PROT_WRITE) == 0) &&
    792 		    ((set_prot(lmp, mpp, 1) == 0) ||
    793 		    (aplist_append(textrel, mpp, AL_CNT_TEXTREL) == NULL))) {
    794 			ret = 0;
    795 			break;
    796 		}
    797 
    798 		/*
    799 		 * Call relocation routine to perform required relocation.
    800 		 */
    801 		switch (rtype) {
    802 		case R_386_COPY:
    803 			if (elf_copy_reloc(name, symref, lmp, (void *)roffset,
    804 			    symdef, _lmp, (const void *)value) == 0)
    805 				ret = 0;
    806 			break;
    807 		case R_386_JMP_SLOT:
    808 			if (((LIST(lmp)->lm_tflags | AFLAGS(lmp)) &
    809 			    (LML_TFLG_AUD_PLTENTER | LML_TFLG_AUD_PLTEXIT)) &&
    810 			    AUDINFO(lmp)->ai_dynplts) {
    811 				int	fail = 0;
    812 				int	pltndx = (((ulong_t)rel -
    813 				    (uintptr_t)JMPREL(lmp)) / relsiz);
    814 				int	symndx = (((uintptr_t)symdef -
    815 				    (uintptr_t)SYMTAB(_lmp)) / SYMENT(_lmp));
    816 
    817 				(void) elf_plt_trace_write(roffset, lmp, _lmp,
    818 				    symdef, symndx, pltndx, (caddr_t)value,
    819 				    sb_flags, &fail);
    820 				if (fail)
    821 					ret = 0;
    822 			} else {
    823 				/*
    824 				 * Write standard PLT entry to jump directly
    825 				 * to newly bound function.
    826 				 */
    827 				DBG_CALL(Dbg_reloc_apply_val(LIST(lmp),
    828 				    ELF_DBG_RTLD, (Xword)roffset,
    829 				    (Xword)value));
    830 				*(ulong_t *)roffset = value;
    831 			}
    832 			break;
    833 		default:
    834 			/*
    835 			 * Write the relocation out.
    836 			 */
    837 			if (do_reloc_rtld(rtype, (uchar_t *)roffset,
    838 			    (Word *)&value, name, NAME(lmp), LIST(lmp)) == 0)
    839 				ret = 0;
    840 
    841 			DBG_CALL(Dbg_reloc_apply_val(LIST(lmp), ELF_DBG_RTLD,
    842 			    (Xword)roffset, (Xword)value));
    843 		}
    844 
    845 		if ((ret == 0) &&
    846 		    ((LIST(lmp)->lm_flags & LML_FLG_TRC_WARN) == 0))
    847 			break;
    848 
    849 		if (binfo) {
    850 			DBG_CALL(Dbg_bind_global(lmp, (Addr)roffset,
    851 			    (Off)(roffset - basebgn), (Xword)(-1), PLT_T_FULL,
    852 			    _lmp, (Addr)value, symdef->st_value, name, binfo));
    853 		}
    854 	}
    855 
    856 	return (relocate_finish(lmp, bound, ret));
    857 }
    858 
    859 /*
    860  * Initialize the first few got entries so that function calls go to
    861  * elf_rtbndr:
    862  *
    863  *	GOT[GOT_XLINKMAP] =	the address of the link map
    864  *	GOT[GOT_XRTLD] =	the address of rtbinder
    865  */
    866 void
    867 elf_plt_init(void *got, caddr_t l)
    868 {
    869 	uint_t		*_got;
    870 	/* LINTED */
    871 	Rt_map		*lmp = (Rt_map *)l;
    872 
    873 	_got = (uint_t *)got + M_GOT_XLINKMAP;
    874 	*_got = (uint_t)lmp;
    875 	_got = (uint_t *)got + M_GOT_XRTLD;
    876 	*_got = (uint_t)elf_rtbndr;
    877 }
    878 
    879 /*
    880  * For SVR4 Intel compatability.  USL uses /usr/lib/libc.so.1 as the run-time
    881  * linker, so the interpreter's address will differ from /usr/lib/ld.so.1.
    882  * Further, USL has special _iob[] and _ctype[] processing that makes up for the
    883  * fact that these arrays do not have associated copy relocations.  So we try
    884  * and make up for that here.  Any relocations found will be added to the global
    885  * copy relocation list and will be processed in setup().
    886  */
    887 static int
    888 _elf_copy_reloc(const char *name, Rt_map *rlmp, Rt_map *dlmp)
    889 {
    890 	Sym		*symref, *symdef;
    891 	caddr_t 	ref, def;
    892 	Rt_map		*_lmp;
    893 	Rel		rel;
    894 	Slookup		sl;
    895 	uint_t		binfo;
    896 
    897 	/*
    898 	 * Determine if the special symbol exists as a reference in the dynamic
    899 	 * executable, and that an associated definition exists in libc.so.1.
    900 	 *
    901 	 * Initialize the symbol lookup data structure.
    902 	 */
    903 	SLOOKUP_INIT(sl, name, rlmp, rlmp, ld_entry_cnt, 0, 0, 0, 0,
    904 	    LKUP_FIRST);
    905 
    906 	if ((symref = lookup_sym(&sl, &_lmp, &binfo, NULL)) == 0)
    907 		return (1);
    908 
    909 	sl.sl_imap = dlmp;
    910 	sl.sl_flags = LKUP_DEFT;
    911 
    912 	if ((symdef = lookup_sym(&sl, &_lmp, &binfo, NULL)) == 0)
    913 		return (1);
    914 	if (strcmp(NAME(_lmp), MSG_ORIG(MSG_PTH_LIBC)))
    915 		return (1);
    916 
    917 	/*
    918 	 * Determine the reference and definition addresses.
    919 	 */
    920 	ref = (void *)(symref->st_value);
    921 	if (!(FLAGS(rlmp) & FLG_RT_FIXED))
    922 		ref += ADDR(rlmp);
    923 	def = (void *)(symdef->st_value);
    924 	if (!(FLAGS(_lmp) & FLG_RT_FIXED))
    925 		def += ADDR(_lmp);
    926 
    927 	/*
    928 	 * Set up a relocation entry for debugging and call the generic copy
    929 	 * relocation function to provide symbol size error checking and to
    930 	 * record the copy relocation that must be performed.
    931 	 */
    932 	rel.r_offset = (Addr)ref;
    933 	rel.r_info = (Word)R_386_COPY;
    934 	DBG_CALL(Dbg_reloc_in(LIST(rlmp), ELF_DBG_RTLD, M_MACH, M_REL_SHT_TYPE,
    935 	    &rel, NULL, 0, name));
    936 
    937 	return (elf_copy_reloc((char *)name, symref, rlmp, (void *)ref, symdef,
    938 	    _lmp, (void *)def));
    939 }
    940 
    941 int
    942 elf_copy_gen(Rt_map *lmp)
    943 {
    944 	if (interp && ((ulong_t)interp->i_faddr !=
    945 	    r_debug.rtd_rdebug.r_ldbase) &&
    946 	    !(strcmp(interp->i_name, MSG_ORIG(MSG_PTH_LIBC)))) {
    947 
    948 		DBG_CALL(Dbg_reloc_run(lmp, M_REL_SHT_TYPE, 0,
    949 		    DBG_REL_START));
    950 
    951 		if (_elf_copy_reloc(MSG_ORIG(MSG_SYM_CTYPE), lmp,
    952 		    (Rt_map *)NEXT(lmp)) == 0)
    953 			return (0);
    954 		if (_elf_copy_reloc(MSG_ORIG(MSG_SYM_IOB), lmp,
    955 		    (Rt_map *)NEXT(lmp)) == 0)
    956 			return (0);
    957 	}
    958 	return (1);
    959 }
    960 
    961 /*
    962  * Plt writing interface to allow debugging initialization to be generic.
    963  */
    964 Pltbindtype
    965 /* ARGSUSED1 */
    966 elf_plt_write(uintptr_t addr, uintptr_t vaddr, void *rptr, uintptr_t symval,
    967 	Xword pltndx)
    968 {
    969 	Rel		*rel = (Rel*)rptr;
    970 	uintptr_t	pltaddr;
    971 
    972 	pltaddr = addr + rel->r_offset;
    973 	*(ulong_t *)pltaddr = (ulong_t)symval;
    974 	DBG_CALL(pltcntfull++);
    975 	return (PLT_T_FULL);
    976 }
    977 
    978 /*
    979  * Provide a machine specific interface to the conversion routine.  By calling
    980  * the machine specific version, rather than the generic version, we insure that
    981  * the data tables/strings for all known machine versions aren't dragged into
    982  * ld.so.1.
    983  */
    984 const char *
    985 _conv_reloc_type(uint_t rel)
    986 {
    987 	static Conv_inv_buf_t	inv_buf;
    988 
    989 	return (conv_reloc_386_type(rel, 0, &inv_buf));
    990 }
    991