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|
/* $OpenBSD: loader.c,v 1.113 2008/05/05 02:29:02 kurt Exp $ */
/*
* Copyright (c) 1998 Per Fogelstrom, Opsycon AB
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#define _DYN_LOADER
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/exec.h>
#include <sys/param.h>
#include <sys/sysctl.h>
#include <nlist.h>
#include <string.h>
#include <link.h>
#include <dlfcn.h>
#include "syscall.h"
#include "archdep.h"
#include "resolve.h"
#include "sod.h"
#include "stdlib.h"
#include "dl_prebind.h"
/*
* Local decls.
*/
static char *_dl_getenv(const char *, char **);
static void _dl_unsetenv(const char *, char **);
unsigned long _dl_boot(const char **, char **, const long, long *);
void _dl_debug_state(void);
void _dl_setup_env(char **);
void _dl_dtors(void);
void _dl_boot_bind(const long, long *, Elf_Dyn *);
void _dl_fixup_user_env(void);
const char *_dl_progname;
int _dl_pagesz;
char *_dl_libpath;
char *_dl_preload;
char *_dl_bindnow;
char *_dl_traceld;
char *_dl_debug;
char *_dl_showmap;
char *_dl_norandom;
char *_dl_noprebind;
char *_dl_prebind_validate;
char *_dl_tracefmt1, *_dl_tracefmt2, *_dl_traceprog;
struct r_debug *_dl_debug_map;
void _dl_dopreload(char *paths);
void
_dl_debug_state(void)
{
/* Debugger stub */
}
/*
* Run dtors for all objects that are eligible.
*/
void
_dl_run_all_dtors()
{
elf_object_t *node;
int fini_complete;
struct dep_node *dnode;
fini_complete = 0;
while (fini_complete == 0) {
fini_complete = 1;
for (node = _dl_objects->next;
node != NULL;
node = node->next) {
if ((node->dyn.fini) &&
(OBJECT_REF_CNT(node) == 0) &&
(node->status & STAT_INIT_DONE) &&
((node->status & STAT_FINI_DONE) == 0)) {
node->status |= STAT_FINI_READY;
}
}
for (node = _dl_objects->next;
node != NULL;
node = node->next ) {
if ((node->dyn.fini) &&
(OBJECT_REF_CNT(node) == 0) &&
(node->status & STAT_INIT_DONE) &&
((node->status & STAT_FINI_DONE) == 0))
TAILQ_FOREACH(dnode, &node->child_list,
next_sib)
dnode->data->status &= ~STAT_FINI_READY;
}
for (node = _dl_objects->next;
node != NULL;
node = node->next ) {
if (node->status & STAT_FINI_READY) {
DL_DEB(("doing dtors obj %p @%p: [%s]\n",
node, node->dyn.fini,
node->load_name));
fini_complete = 0;
node->status |= STAT_FINI_DONE;
node->status &= ~STAT_FINI_READY;
(*node->dyn.fini)();
}
}
}
}
/*
* Routine to walk through all of the objects except the first
* (main executable).
*
* Big question, should dlopen()ed objects be unloaded before or after
* the destructor for the main application runs?
*/
void
_dl_dtors(void)
{
_dl_thread_kern_stop();
/* ORDER? */
_dl_unload_dlopen();
DL_DEB(("doing dtors\n"));
/* main program runs its dtors itself
* but we want to run dtors on all it's children);
*/
_dl_objects->status |= STAT_FINI_DONE;
_dl_objects->opencount--;
_dl_notify_unload_shlib(_dl_objects);
_dl_run_all_dtors();
}
void
_dl_dopreload(char *paths)
{
char *cp, *dp;
elf_object_t *shlib;
dp = paths = _dl_strdup(paths);
if (dp == NULL) {
_dl_printf("preload: out of memory");
_dl_exit(1);
}
while ((cp = _dl_strsep(&dp, ":")) != NULL) {
shlib = _dl_load_shlib(cp, _dl_objects, OBJTYPE_LIB,
_dl_objects->obj_flags);
if (shlib == NULL) {
_dl_printf("%s: can't load library '%s'\n",
_dl_progname, cp);
_dl_exit(4);
}
_dl_add_object(shlib);
_dl_link_child(shlib, _dl_objects);
}
_dl_free(paths);
return;
}
/*
* grab interesting environment variables, zap bad env vars if
* issetugid
*/
char **_dl_so_envp;
void
_dl_setup_env(char **envp)
{
/*
* Get paths to various things we are going to use.
*/
_dl_libpath = _dl_getenv("LD_LIBRARY_PATH", envp);
_dl_preload = _dl_getenv("LD_PRELOAD", envp);
_dl_bindnow = _dl_getenv("LD_BIND_NOW", envp);
_dl_traceld = _dl_getenv("LD_TRACE_LOADED_OBJECTS", envp);
_dl_tracefmt1 = _dl_getenv("LD_TRACE_LOADED_OBJECTS_FMT1", envp);
_dl_tracefmt2 = _dl_getenv("LD_TRACE_LOADED_OBJECTS_FMT2", envp);
_dl_traceprog = _dl_getenv("LD_TRACE_LOADED_OBJECTS_PROGNAME", envp);
_dl_debug = _dl_getenv("LD_DEBUG", envp);
_dl_norandom = _dl_getenv("LD_NORANDOM", envp);
_dl_noprebind = _dl_getenv("LD_NOPREBIND", envp);
_dl_prebind_validate = _dl_getenv("LD_PREBINDVALIDATE", envp);
/*
* Don't allow someone to change the search paths if he runs
* a suid program without credentials high enough.
*/
if (_dl_issetugid()) { /* Zap paths if s[ug]id... */
if (_dl_libpath) {
_dl_libpath = NULL;
_dl_unsetenv("LD_LIBRARY_PATH", envp);
}
if (_dl_preload) {
_dl_preload = NULL;
_dl_unsetenv("LD_PRELOAD", envp);
}
if (_dl_bindnow) {
_dl_bindnow = NULL;
_dl_unsetenv("LD_BIND_NOW", envp);
}
if (_dl_debug) {
_dl_debug = NULL;
_dl_unsetenv("LD_DEBUG", envp);
}
if (_dl_norandom) {
_dl_norandom = NULL;
_dl_unsetenv("LD_NORANDOM", envp);
}
}
_dl_so_envp = envp;
}
int
_dl_load_dep_libs(elf_object_t *object, int flags, int booting)
{
elf_object_t *dynobj;
Elf_Dyn *dynp;
unsigned int loop;
int libcount;
int depflags;
dynobj = object;
while (dynobj) {
DL_DEB(("examining: '%s'\n", dynobj->load_name));
libcount = 0;
/* propagate RTLD_NOW to deplibs (can be set by dynamic tags) */
depflags = flags | (dynobj->obj_flags & RTLD_NOW);
for (dynp = dynobj->load_dyn; dynp->d_tag; dynp++) {
if (dynp->d_tag == DT_NEEDED) {
libcount++;
}
}
if ( libcount != 0) {
struct listent {
Elf_Dyn *dynp;
elf_object_t *depobj;
} *liblist;
int *randomlist;
liblist = _dl_malloc(libcount * sizeof(struct listent));
randomlist = _dl_malloc(libcount * sizeof(int));
if (liblist == NULL)
_dl_exit(5);
for (dynp = dynobj->load_dyn, loop = 0; dynp->d_tag;
dynp++)
if (dynp->d_tag == DT_NEEDED)
liblist[loop++].dynp = dynp;
/* Randomize these */
for (loop = 0; loop < libcount; loop++)
randomlist[loop] = loop;
if (!_dl_norandom)
for (loop = 1; loop < libcount; loop++) {
unsigned int rnd;
int cur;
rnd = _dl_random();
rnd = rnd % (loop+1);
cur = randomlist[rnd];
randomlist[rnd] = randomlist[loop];
randomlist[loop] = cur;
}
for (loop = 0; loop < libcount; loop++) {
elf_object_t *depobj;
const char *libname;
libname = dynobj->dyn.strtab;
libname +=
liblist[randomlist[loop]].dynp->d_un.d_val;
DL_DEB(("loading: %s required by %s\n", libname,
dynobj->load_name));
depobj = _dl_load_shlib(libname, dynobj,
OBJTYPE_LIB, depflags);
if (depobj == 0) {
if (booting) {
_dl_printf(
"%s: can't load library '%s'\n",
_dl_progname, libname);
_dl_exit(4);
} else {
DL_DEB(("dlopen: failed to open %s\n",
libname));
_dl_free(liblist);
return (1);
}
}
liblist[randomlist[loop]].depobj = depobj;
}
for (loop = 0; loop < libcount; loop++) {
_dl_add_object(liblist[loop].depobj);
_dl_link_child(liblist[loop].depobj, dynobj);
}
_dl_free(liblist);
}
dynobj = dynobj->next;
}
/* add first object manually */
_dl_link_grpsym(object);
_dl_cache_grpsym_list(object);
return(0);
}
#define PFLAGS(X) ((((X) & PF_R) ? PROT_READ : 0) | \
(((X) & PF_W) ? PROT_WRITE : 0) | \
(((X) & PF_X) ? PROT_EXEC : 0))
/*
* This is the dynamic loader entrypoint. When entering here, depending
* on architecture type, the stack and registers are set up according
* to the architectures ABI specification. The first thing required
* to do is to dig out all information we need to accomplish our task.
*/
unsigned long
_dl_boot(const char **argv, char **envp, const long loff, long *dl_data)
{
struct elf_object *exe_obj; /* Pointer to executable object */
struct elf_object *dyn_obj; /* Pointer to executable object */
struct r_debug **map_link; /* Where to put pointer for gdb */
struct r_debug *debug_map;
struct load_list *next_load, *load_list = NULL;
Elf_Dyn *dynp;
Elf_Phdr *phdp;
Elf_Ehdr *ehdr;
char *us = "";
unsigned int loop;
int failed;
struct dep_node *n;
_dl_setup_env(envp);
_dl_progname = argv[0];
if (dl_data[AUX_pagesz] != 0)
_dl_pagesz = dl_data[AUX_pagesz];
else
_dl_pagesz = 4096;
/*
* now that GOT and PLT has been relocated, and we know
* page size, protect it from modification
*/
#ifndef RTLD_NO_WXORX
{
extern char *__got_start;
extern char *__got_end;
#ifdef RTLD_PROTECT_PLT
extern char *__plt_start;
extern char *__plt_end;
#endif
_dl_mprotect((void *)ELF_TRUNC((long)&__got_start, _dl_pagesz),
ELF_ROUND((long)&__got_end,_dl_pagesz) -
ELF_TRUNC((long)&__got_start, _dl_pagesz),
GOT_PERMS);
#ifdef RTLD_PROTECT_PLT
/* only for DATA_PLT or BSS_PLT */
_dl_mprotect((void *)ELF_TRUNC((long)&__plt_start, _dl_pagesz),
ELF_ROUND((long)&__plt_end,_dl_pagesz) -
ELF_TRUNC((long)&__plt_start, _dl_pagesz),
PROT_READ|PROT_EXEC);
#endif
}
#endif
DL_DEB(("rtld loading: '%s'\n", _dl_progname));
/* init this in runtime, not statically */
TAILQ_INIT(&_dlopened_child_list);
exe_obj = NULL;
_dl_loading_object = NULL;
/*
* Examine the user application and set up object information.
*/
phdp = (Elf_Phdr *)dl_data[AUX_phdr];
for (loop = 0; loop < dl_data[AUX_phnum]; loop++) {
if (phdp->p_type == PT_DYNAMIC) {
exe_obj = _dl_finalize_object(argv[0] ? argv[0] : "",
(Elf_Dyn *)phdp->p_vaddr, (Elf_Phdr *)dl_data[AUX_phdr],
dl_data[AUX_phnum], OBJTYPE_EXE, 0, 0);
_dl_add_object(exe_obj);
} else if (phdp->p_type == PT_INTERP) {
us = _dl_strdup((char *)phdp->p_vaddr);
} else if (phdp->p_type == PT_LOAD) {
int align = _dl_pagesz - 1;
int size = (phdp->p_vaddr & align) + phdp->p_filesz;
#define TRUNC_PG(x) ((x) & ~(align))
next_load = _dl_malloc(sizeof(struct load_list));
next_load->next = load_list;
load_list = next_load;
next_load->start = (char *)TRUNC_PG(phdp->p_vaddr);
next_load->size = size;
next_load->prot = PFLAGS(phdp->p_flags);
if (phdp->p_flags & 0x08000000) {
// dump_prelink(phdp->p_vaddr, phdp->p_memsz);
prebind_load_exe(phdp, exe_obj);
}
}
phdp++;
}
exe_obj->load_list = load_list;
exe_obj->obj_flags |= RTLD_GLOBAL;
n = _dl_malloc(sizeof *n);
if (n == NULL)
_dl_exit(5);
n->data = exe_obj;
TAILQ_INSERT_TAIL(&_dlopened_child_list, n, next_sib);
exe_obj->opencount++;
if (_dl_preload != NULL)
_dl_dopreload(_dl_preload);
_dl_load_dep_libs(exe_obj, exe_obj->obj_flags, 1);
/*
* Now add the dynamic loader itself last in the object list
* so we can use the _dl_ code when serving dl.... calls.
* Intentionally left off the exe child_list.
*/
dynp = (Elf_Dyn *)((void *)_DYNAMIC);
ehdr = (Elf_Ehdr *)dl_data[AUX_base];
dyn_obj = _dl_finalize_object(us, dynp,
(Elf_Phdr *)((char *)dl_data[AUX_base] + ehdr->e_phoff),
ehdr->e_phnum, OBJTYPE_LDR, dl_data[AUX_base], loff);
_dl_add_object(dyn_obj);
dyn_obj->refcount++;
_dl_link_grpsym(dyn_obj);
dyn_obj->status |= STAT_RELOC_DONE;
/*
* Everything should be in place now for doing the relocation
* and binding. Call _dl_rtld to do the job. Fingers crossed.
*/
_dl_prebind_pre_resolve();
failed = 0;
if (_dl_traceld == NULL)
failed = _dl_rtld(_dl_objects);
_dl_prebind_post_resolve();
if (_dl_debug || _dl_traceld)
_dl_show_objects();
DL_DEB(("dynamic loading done, %s.\n",
(failed == 0) ? "success":"failed"));
if (failed != 0)
_dl_exit(1);
if (_dl_traceld)
_dl_exit(0);
_dl_loading_object = NULL;
_dl_fixup_user_env();
/*
* Finally make something to help gdb when poking around in the code.
*/
#ifdef __mips__
map_link = (struct r_debug **)(exe_obj->Dyn.info[DT_MIPS_RLD_MAP -
DT_LOPROC + DT_NUM]);
#else
map_link = NULL;
for (dynp = exe_obj->load_dyn; dynp->d_tag; dynp++) {
if (dynp->d_tag == DT_DEBUG) {
map_link = (struct r_debug **)&dynp->d_un.d_ptr;
break;
}
}
if (dynp->d_tag != DT_DEBUG)
DL_DEB(("failed to mark DTDEBUG\n"));
#endif
if (map_link) {
debug_map = (struct r_debug *)_dl_malloc(sizeof(*debug_map));
debug_map->r_version = 1;
debug_map->r_map = (struct link_map *)_dl_objects;
debug_map->r_brk = (Elf_Addr)_dl_debug_state;
debug_map->r_state = RT_CONSISTENT;
debug_map->r_ldbase = loff;
_dl_debug_map = debug_map;
*map_link = _dl_debug_map;
}
_dl_debug_state();
/*
* The first object is the executable itself,
* it is responsible for running it's own ctors/dtors
* thus do NOT run the ctors for the executable, all of
* the shared libraries which follow.
* Do not run init code if run from ldd.
*/
if (_dl_objects->next != NULL) {
_dl_objects->status |= STAT_INIT_DONE;
_dl_call_init(_dl_objects);
}
/*
* Schedule a routine to be run at shutdown, by using atexit.
* Cannot call atexit directly from ld.so?
* Do not schedule destructors if run from ldd.
*/
{
const elf_object_t *sobj;
const Elf_Sym *sym;
Elf_Addr ooff;
sym = NULL;
ooff = _dl_find_symbol("atexit", &sym,
SYM_SEARCH_ALL|SYM_NOWARNNOTFOUND|SYM_PLT,
NULL, dyn_obj, &sobj);
if (sym == NULL)
_dl_printf("cannot find atexit, destructors will not be run!\n");
else
#ifdef MD_ATEXIT
MD_ATEXIT(sobj, sym, (Elf_Addr)&_dl_dtors);
#else
(*(void (*)(Elf_Addr))(sym->st_value + ooff))
((Elf_Addr)_dl_dtors);
#endif
}
DL_DEB(("entry point: 0x%lx\n", dl_data[AUX_entry]));
/*
* Return the entry point.
*/
return(dl_data[AUX_entry]);
}
void
_dl_boot_bind(const long sp, long *dl_data, Elf_Dyn *dynamicp)
{
struct elf_object dynld; /* Resolver data for the loader */
AuxInfo *auxstack;
long *stack;
Elf_Dyn *dynp;
int n, argc;
char **argv, **envp;
long loff;
/*
* Scan argument and environment vectors. Find dynamic
* data vector put after them.
*/
stack = (long *)sp;
argc = *stack++;
argv = (char **)stack;
envp = &argv[argc + 1];
stack = (long *)envp;
while (*stack++ != NULL)
;
/*
* Zero out dl_data.
*/
for (n = 0; n < AUX_entry; n++)
dl_data[n] = 0;
/*
* Dig out auxiliary data set up by exec call. Move all known
* tags to an indexed local table for easy access.
*/
for (auxstack = (AuxInfo *)stack; auxstack->au_id != AUX_null;
auxstack++) {
if (auxstack->au_id > AUX_entry)
continue;
dl_data[auxstack->au_id] = auxstack->au_v;
}
loff = dl_data[AUX_base]; /* XXX assumes linked at 0x0 */
/*
* We need to do 'selfreloc' in case the code weren't
* loaded at the address it was linked to.
*
* Scan the DYNAMIC section for the loader.
* Cache the data for easier access.
*/
#if defined(__alpha__)
dynp = (Elf_Dyn *)((long)_DYNAMIC);
#elif defined(__sparc__) || defined(__sparc64__) || defined(__powerpc__) || \
defined(__hppa__) || defined(__sh__)
dynp = dynamicp;
#else
dynp = (Elf_Dyn *)((long)_DYNAMIC + loff);
#endif
while (dynp != NULL && dynp->d_tag != DT_NULL) {
if (dynp->d_tag < DT_NUM)
dynld.Dyn.info[dynp->d_tag] = dynp->d_un.d_val;
else if (dynp->d_tag >= DT_LOPROC &&
dynp->d_tag < DT_LOPROC + DT_PROCNUM)
dynld.Dyn.info[dynp->d_tag - DT_LOPROC + DT_NUM] =
dynp->d_un.d_val;
if (dynp->d_tag == DT_TEXTREL)
dynld.dyn.textrel = 1;
dynp++;
}
/*
* Do the 'bootstrap relocation'. This is really only needed if
* the code was loaded at another location than it was linked to.
* We don't do undefined symbols resolving (to difficult..)
*/
/* "relocate" dyn.X values if they represent addresses */
{
int i, val;
/* must be code, not pic data */
int table[20];
i = 0;
table[i++] = DT_PLTGOT;
table[i++] = DT_HASH;
table[i++] = DT_STRTAB;
table[i++] = DT_SYMTAB;
table[i++] = DT_RELA;
table[i++] = DT_INIT;
table[i++] = DT_FINI;
table[i++] = DT_REL;
table[i++] = DT_JMPREL;
/* other processors insert their extras here */
table[i++] = DT_NULL;
for (i = 0; table[i] != DT_NULL; i++) {
val = table[i];
if (val > DT_HIPROC) /* ??? */
continue;
if (val > DT_LOPROC)
val -= DT_LOPROC + DT_NUM;
if (dynld.Dyn.info[val] != 0)
dynld.Dyn.info[val] += loff;
}
}
{
u_int32_t rs;
Elf_Rel *rp;
int i;
rp = (Elf_Rel *)(dynld.Dyn.info[DT_REL]);
rs = dynld.dyn.relsz;
for (i = 0; i < rs; i += sizeof (Elf_Rel)) {
Elf_Addr *ra;
const Elf_Sym *sp;
sp = dynld.dyn.symtab;
sp += ELF_R_SYM(rp->r_info);
if (ELF_R_SYM(rp->r_info) && sp->st_value == 0) {
#if 0
/* cannot printf in this function */
_dl_wrstderr("Dynamic loader failure: self bootstrapping impossible.\n");
_dl_wrstderr("Undefined symbol: ");
_dl_wrstderr((char *)dynld.dyn.strtab +
sp->st_name);
#endif
_dl_exit(5);
}
ra = (Elf_Addr *)(rp->r_offset + loff);
RELOC_REL(rp, sp, ra, loff);
rp++;
}
}
for (n = 0; n < 2; n++) {
unsigned long rs;
Elf_RelA *rp;
int i;
switch (n) {
case 0:
rp = (Elf_RelA *)(dynld.Dyn.info[DT_JMPREL]);
rs = dynld.dyn.pltrelsz;
break;
case 1:
rp = (Elf_RelA *)(dynld.Dyn.info[DT_RELA]);
rs = dynld.dyn.relasz;
break;
default:
rp = NULL;
rs = 0;
}
for (i = 0; i < rs; i += sizeof (Elf_RelA)) {
Elf_Addr *ra;
const Elf_Sym *sp;
sp = dynld.dyn.symtab;
sp += ELF_R_SYM(rp->r_info);
if (ELF_R_SYM(rp->r_info) && sp->st_value == 0) {
#if 0
_dl_wrstderr("Dynamic loader failure: self bootstrapping impossible.\n");
_dl_wrstderr("Undefined symbol: ");
_dl_wrstderr((char *)dynld.dyn.strtab +
sp->st_name);
#endif
_dl_exit(6);
}
ra = (Elf_Addr *)(rp->r_offset + loff);
RELOC_RELA(rp, sp, ra, loff);
rp++;
}
}
RELOC_GOT(&dynld, loff);
/*
* we have been fully relocated here, so most things no longer
* need the loff adjustment
*/
}
#define DL_SM_SYMBUF_CNT 512
sym_cache _dl_sm_symcache_buffer[DL_SM_SYMBUF_CNT];
int
_dl_rtld(elf_object_t *object)
{
size_t sz;
int fails = 0;
if (object->next)
fails += _dl_rtld(object->next);
if (object->status & STAT_RELOC_DONE)
return 0;
sz = 0;
if (object->nchains < DL_SM_SYMBUF_CNT) {
_dl_symcache = _dl_sm_symcache_buffer;
// DL_DEB(("using static buffer for %d entries\n",
// object->nchains));
_dl_memset(_dl_symcache, 0,
sizeof (sym_cache) * object->nchains);
} else {
sz = ELF_ROUND(sizeof (sym_cache) * object->nchains,
_dl_pagesz);
// DL_DEB(("allocating symcache sz %x with mmap\n", sz));
_dl_symcache = (void *)_dl_mmap(0, sz, PROT_READ|PROT_WRITE,
MAP_PRIVATE|MAP_ANON, -1, 0);
if (_dl_symcache == (void *)MAP_FAILED) {
sz = 0;
_dl_symcache = NULL;
}
}
prebind_symcache(object, SYM_NOTPLT);
/*
* Do relocation information first, then GOT.
*/
fails =_dl_md_reloc(object, DT_REL, DT_RELSZ);
fails += _dl_md_reloc(object, DT_RELA, DT_RELASZ);
prebind_symcache(object, SYM_PLT);
fails += _dl_md_reloc_got(object, !(_dl_bindnow ||
object->obj_flags & RTLD_NOW));
if (_dl_symcache != NULL) {
if (sz != 0)
_dl_munmap( _dl_symcache, sz);
_dl_symcache = NULL;
}
if (fails == 0)
object->status |= STAT_RELOC_DONE;
return (fails);
}
void
_dl_call_init(elf_object_t *object)
{
struct dep_node *n;
TAILQ_FOREACH(n, &object->child_list, next_sib) {
if (n->data->status & STAT_INIT_DONE)
continue;
_dl_call_init(n->data);
}
if (object->status & STAT_INIT_DONE)
return;
if (object->dyn.init) {
DL_DEB(("doing ctors obj %p @%p: [%s]\n",
object, object->dyn.init, object->load_name));
(*object->dyn.init)();
}
/* What about loops? */
object->status |= STAT_INIT_DONE;
}
static char *
_dl_getenv(const char *var, char **env)
{
const char *ep;
while ((ep = *env++)) {
const char *vp = var;
while (*vp && *vp == *ep) {
vp++;
ep++;
}
if (*vp == '\0' && *ep++ == '=')
return((char *)ep);
}
return(NULL);
}
static void
_dl_unsetenv(const char *var, char **env)
{
char *ep;
while ((ep = *env)) {
const char *vp = var;
while (*vp && *vp == *ep) {
vp++;
ep++;
}
if (*vp == '\0' && *ep++ == '=') {
char **P;
for (P = env;; ++P)
if (!(*P = *(P + 1)))
break;
} else
env++;
}
}
/*
* _dl_fixup_user_env()
*
* Set the user environment so that programs can use the environment
* while running constructors. Specifically, MALLOC_OPTIONS= for malloc()
*/
void
_dl_fixup_user_env(void)
{
const Elf_Sym *sym;
Elf_Addr ooff;
struct elf_object dummy_obj;
dummy_obj.dyn.symbolic = 0;
dummy_obj.load_name = "ld.so";
sym = NULL;
ooff = _dl_find_symbol("environ", &sym,
SYM_SEARCH_ALL|SYM_NOWARNNOTFOUND|SYM_PLT, NULL, &dummy_obj, NULL);
if (sym != NULL)
*((char ***)(sym->st_value + ooff)) = _dl_so_envp;
}
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