ldso/ldso/ldso.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Program to load an ELF binary on a linux system, and run it
   4  * after resolving ELF shared library symbols
   5  *
   6  * Copyright (C) 2005 by Joakim Tjernlund
   7  * Copyright (C) 2000-2006 by Erik Andersen <andersen@codepoet.org>
   8  * Copyright (c) 1994-2000 Eric Youngdale, Peter MacDonald,
   9  *                              David Engel, Hongjiu Lu and Mitch D'Souza
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. The name of the above contributors may not be
  17  *    used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "ldso.h"
  34 #include "unsecvars.h"
  35
  36 /* Pull in common debug code */
  37 #include "dl-debug.c"
  38
  39 #define ALLOW_ZERO_PLTGOT
  40
  41 /* Pull in the value of _dl_progname */
  42 #include LDSO_ELFINTERP
  43
  44 /* Global variables used within the shared library loader */
  45 char *_dl_library_path         = 0;     /* Where we look for libraries */
  46 char *_dl_preload              = 0;     /* Things to be loaded before the libs */
  47 char *_dl_ldsopath             = 0;     /* Location of the shared lib loader */
  48 int _dl_secure                 = 1;     /* Are we dealing with setuid stuff? */
  49 int _dl_errno                  = 0;     /* We can't use the real errno in ldso */
  50 size_t _dl_pagesize            = 0;     /* Store the page size for use later */
  51 struct r_debug *_dl_debug_addr = NULL;  /* Used to communicate with the gdb debugger */
  52 void *(*_dl_malloc_function) (size_t size) = NULL;
  53
  54 #ifdef __SUPPORT_LD_DEBUG__
  55 char *_dl_debug           = 0;
  56 char *_dl_debug_symbols   = 0;
  57 char *_dl_debug_move      = 0;
  58 char *_dl_debug_reloc     = 0;
  59 char *_dl_debug_detail    = 0;
  60 char *_dl_debug_nofixups  = 0;
  61 char *_dl_debug_bindings  = 0;
  62 int   _dl_debug_file      = 2;
  63 #endif
  64
  65 /* Needed for standalone execution. */
  66 unsigned long attribute_hidden _dl_skip_args = 0;
  67 const char *_dl_progname = UCLIBC_LDSO;      /* The name of the executable being run */
  68 #include "dl-startup.c"
  69 /* Forward function declarations */
  70 static int _dl_suid_ok(void);
  71
  72 /*
  73  * This stub function is used by some debuggers.  The idea is that they
  74  * can set an internal breakpoint on it, so that we are notified when the
  75  * address mapping is changed in some way.
  76  */
  77 void _dl_debug_state(void);
  78 void _dl_debug_state()
  79 {
  80 }
  81
  82 static unsigned char *_dl_malloc_addr = 0;      /* Lets _dl_malloc use the already allocated memory page */
  83 static unsigned char *_dl_mmap_zero   = 0;      /* Also used by _dl_malloc */
  84
  85 static struct elf_resolve **init_fini_list;
  86 static unsigned int nlist; /* # items in init_fini_list */
  87 extern void _start(void);
  88
  89 #ifdef __UCLIBC_HAS_SSP__
  90 # include <dl-osinfo.h>
  91 uintptr_t stack_chk_guard;
  92 # ifndef THREAD_SET_STACK_GUARD
  93 /* Only exported for architectures that don't store the stack guard canary
  94  * in local thread area.  */
  95 uintptr_t __stack_chk_guard attribute_relro;
  96 #  ifdef __UCLIBC_HAS_SSP_COMPAT__
  97 strong_alias(__stack_chk_guard,__guard)
  98 #  endif
  99 # elif __UCLIBC_HAS_SSP_COMPAT__
 100 uintptr_t __guard attribute_relro;
 101 # endif
 102 #endif
 103
 104 static void _dl_run_array_forward(unsigned long array, unsigned long size,
 105                                   DL_LOADADDR_TYPE loadaddr)
 106 {
 107         if (array != 0) {
 108                 unsigned int j;
 109                 unsigned int jm;
 110                 ElfW(Addr) *addrs;
 111                 jm = size / sizeof (ElfW(Addr));
 112                 addrs = (ElfW(Addr) *) DL_RELOC_ADDR(loadaddr, array);
 113                 for (j = 0; j < jm; ++j) {
 114                         void (*dl_elf_func) (void);
 115                         dl_elf_func = (void (*)(void)) (intptr_t) addrs[j];
 116                         DL_CALL_FUNC_AT_ADDR (dl_elf_func, loadaddr, (void (*)(void)));
 117                 }
 118         }
 119 }
 120
 121 void _dl_run_init_array(struct elf_resolve *tpnt);
 122 void _dl_run_init_array(struct elf_resolve *tpnt)
 123 {
 124         _dl_run_array_forward(tpnt->dynamic_info[DT_INIT_ARRAY],
 125                               tpnt->dynamic_info[DT_INIT_ARRAYSZ],
 126                               tpnt->loadaddr);
 127 }
 128
 129 void _dl_app_init_array(void);
 130 void _dl_app_init_array(void)
 131 {
 132         _dl_run_init_array(_dl_loaded_modules);
 133 }
 134
 135 void _dl_run_fini_array(struct elf_resolve *tpnt);
 136 void _dl_run_fini_array(struct elf_resolve *tpnt)
 137 {
 138         if (tpnt->dynamic_info[DT_FINI_ARRAY]) {
 139                 ElfW(Addr) *array = (ElfW(Addr) *) DL_RELOC_ADDR(tpnt->loadaddr, tpnt->dynamic_info[DT_FINI_ARRAY]);
 140                 unsigned int i = (tpnt->dynamic_info[DT_FINI_ARRAYSZ] / sizeof(ElfW(Addr)));
 141                 while (i-- > 0) {
 142                         void (*dl_elf_func) (void);
 143                         dl_elf_func = (void (*)(void)) (intptr_t) array[i];
 144                         DL_CALL_FUNC_AT_ADDR (dl_elf_func, tpnt->loadaddr, (void (*)(void)));
 145                 }
 146         }
 147 }
 148
 149 void _dl_app_fini_array(void);
 150 void _dl_app_fini_array(void)
 151 {
 152         _dl_run_fini_array(_dl_loaded_modules);
 153 }
 154
 155 static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void)
 156 {
 157         int i;
 158         struct elf_resolve * tpnt;
 159
 160         for (i = 0; i < nlist; ++i) {
 161                 tpnt = init_fini_list[i];
 162                 if (tpnt->init_flag & FINI_FUNCS_CALLED)
 163                         continue;
 164                 tpnt->init_flag |= FINI_FUNCS_CALLED;
 165                 _dl_run_fini_array(tpnt);
 166                 if (tpnt->dynamic_info[DT_FINI]) {
 167                         void (*dl_elf_func) (void);
 168
 169                         dl_elf_func = (void (*)(void)) (intptr_t) DL_RELOC_ADDR(tpnt->loadaddr, tpnt->dynamic_info[DT_FINI]);
 170                         _dl_if_debug_dprint("\ncalling FINI: %s\n\n", tpnt->libname);
 171                         DL_CALL_FUNC_AT_ADDR (dl_elf_func, tpnt->loadaddr, (void(*)(void)));
 172                 }
 173         }
 174 }
 175
 176 void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
 177                           ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp,
 178                           char **argv)
 179 {
 180         ElfW(Phdr) *ppnt;
 181         ElfW(Dyn) *dpnt;
 182         char *lpntstr;
 183         unsigned int i;
 184         int unlazy = 0, trace_loaded_objects = 0;
 185         struct dyn_elf *rpnt;
 186         struct elf_resolve *tcurr;
 187         struct elf_resolve *tpnt1;
 188         struct elf_resolve app_tpnt_tmp;
 189         struct elf_resolve *app_tpnt = &app_tpnt_tmp;
 190         struct r_debug *debug_addr;
 191         unsigned long *lpnt;
 192         unsigned long *_dl_envp;                /* The environment address */
 193         ElfW(Addr) relro_addr = 0;
 194         size_t relro_size = 0;
 195         struct stat st;
 196
 197         /* Wahoo!!! We managed to make a function call!  Get malloc
 198          * setup so we can use _dl_dprintf() to print debug noise
 199          * instead of the SEND_STDERR macros used in dl-startup.c */
 200
 201         _dl_memset(app_tpnt, 0x00, sizeof(*app_tpnt));
 202
 203         /* Store the page size for later use */
 204         _dl_pagesize = (auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE;
 205         /* Make it so _dl_malloc can use the page of memory we have already
 206          * allocated.  We shouldn't need to grab any more memory.  This must
 207          * be first since things like _dl_dprintf() use _dl_malloc()...
 208          */
 209         _dl_malloc_addr = (unsigned char *)_dl_pagesize;
 210         _dl_mmap_zero = 0;
 211
 212         /* Wahoo!!! */
 213         _dl_debug_early("Cool, ldso survived making function calls\n");
 214
 215         /* Now we have done the mandatory linking of some things.  We are now
 216          * free to start using global variables, since these things have all
 217          * been fixed up by now.  Still no function calls outside of this
 218          * library, since the dynamic resolver is not yet ready.
 219          */
 220         if (argv[0]) {
 221                 _dl_progname = argv[0];
 222         }
 223
 224         if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) {
 225                 _dl_dprintf(_dl_debug_file, "Standalone execution is not supported yet\n");
 226                 _dl_exit(1);
 227         }
 228
 229         /* Start to build the tables of the modules that are required for
 230          * this beast to run.  We start with the basic executable, and then
 231          * go from there.  Eventually we will run across ourself, and we
 232          * will need to properly deal with that as well.
 233          */
 234         rpnt = NULL;
 235         if (_dl_getenv("LD_BIND_NOW", envp))
 236                 unlazy = RTLD_NOW;
 237
 238         /* Now we need to figure out what kind of options are selected.
 239          * Note that for SUID programs we ignore the settings in
 240          * LD_LIBRARY_PATH.
 241          */
 242         if ((auxvt[AT_UID].a_un.a_val == (size_t)-1 && _dl_suid_ok()) ||
 243             (auxvt[AT_UID].a_un.a_val != (size_t)-1 &&
 244              auxvt[AT_UID].a_un.a_val == auxvt[AT_EUID].a_un.a_val &&
 245              auxvt[AT_GID].a_un.a_val == auxvt[AT_EGID].a_un.a_val)) {
 246                 _dl_secure = 0;
 247                 _dl_preload = _dl_getenv("LD_PRELOAD", envp);
 248                 _dl_library_path = _dl_getenv("LD_LIBRARY_PATH", envp);
 249         } else {
 250                 static const char unsecure_envvars[] =
 251 #ifdef EXTRA_UNSECURE_ENVVARS
 252                         EXTRA_UNSECURE_ENVVARS
 253 #endif
 254                         UNSECURE_ENVVARS;
 255                 const char *nextp;
 256                 _dl_secure = 1;
 257
 258                 nextp = unsecure_envvars;
 259                 do {
 260                         _dl_unsetenv (nextp, envp);
 261                         /* We could use rawmemchr but this need not be fast.  */
 262                         nextp = (char *) _dl_strchr(nextp, '\0') + 1;
 263                 } while (*nextp != '\0');
 264                 _dl_preload = NULL;
 265                 _dl_library_path = NULL;
 266                 /* SUID binaries can be exploited if they do LAZY relocation. */
 267                 unlazy = RTLD_NOW;
 268         }
 269
 270         /* sjhill: your TLS init should go before this */
 271 #ifdef __UCLIBC_HAS_SSP__
 272         /* Set up the stack checker's canary.  */
 273         stack_chk_guard = _dl_setup_stack_chk_guard ();
 274 # ifdef THREAD_SET_STACK_GUARD
 275         THREAD_SET_STACK_GUARD (stack_chk_guard);
 276 #  ifdef __UCLIBC_HAS_SSP_COMPAT__
 277         __guard = stack_chk_guard;
 278 #  endif
 279 # else
 280         __stack_chk_guard = stack_chk_guard;
 281 # endif
 282 #endif
 283
 284         /* At this point we are now free to examine the user application,
 285          * and figure out which libraries are supposed to be called.  Until
 286          * we have this list, we will not be completely ready for dynamic
 287          * linking.
 288          */
 289
 290         /* Find the runtime load address of the main executable.  This may be
 291          * different from what the ELF header says for ET_DYN/PIE executables.
 292          */
 293         {
 294                 unsigned int idx;
 295                 ElfW(Phdr) *phdr = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 296
 297                 for (idx = 0; idx < auxvt[AT_PHNUM].a_un.a_val; idx++, phdr++)
 298                         if (phdr->p_type == PT_PHDR) {
 299                                 DL_INIT_LOADADDR_PROG(app_tpnt->loadaddr, auxvt[AT_PHDR].a_un.a_val - phdr->p_vaddr);
 300                                 break;
 301                         }
 302
 303                 if (DL_LOADADDR_BASE(app_tpnt->loadaddr))
 304                         _dl_debug_early("Position Independent Executable: "
 305                                         "app_tpnt->loadaddr=%x\n", DL_LOADADDR_BASE(app_tpnt->loadaddr));
 306         }
 307
 308         /*
 309          * This is used by gdb to locate the chain of shared libraries that are
 310          * currently loaded.
 311          */
 312         debug_addr = _dl_malloc(sizeof(struct r_debug));
 313         _dl_memset(debug_addr, 0, sizeof(struct r_debug));
 314
 315         ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 316         for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
 317                 if (ppnt->p_type == PT_GNU_RELRO) {
 318                         relro_addr = ppnt->p_vaddr;
 319                         relro_size = ppnt->p_memsz;
 320                 }
 321                 if (ppnt->p_type == PT_DYNAMIC) {
 322                         dpnt = (ElfW(Dyn) *) DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr);
 323                         _dl_parse_dynamic_info(dpnt, app_tpnt->dynamic_info, debug_addr, app_tpnt->loadaddr);
 324 #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
 325                         /* Ugly, ugly.  We need to call mprotect to change the
 326                          * protection of the text pages so that we can do the
 327                          * dynamic linking.  We can set the protection back
 328                          * again once we are done.
 329                          */
 330                         _dl_debug_early("calling mprotect on the application program\n");
 331                         /* Now cover the application program. */
 332                         if (app_tpnt->dynamic_info[DT_TEXTREL]) {
 333                                 ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 334                                 for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
 335                                         if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W))
 336                                                 _dl_mprotect((void *) (DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr) & PAGE_ALIGN),
 337                                                              ((ppnt->p_vaddr + app_tpnt->loadaddr) & ADDR_ALIGN) +
 338                                                              (unsigned long) ppnt->p_filesz,
 339                                                              PROT_READ | PROT_WRITE | PROT_EXEC);
 340                                 }
 341                         }
 342 #endif
 343
 344 #ifndef ALLOW_ZERO_PLTGOT
 345                         /* make sure it's really there. */
 346                         if (app_tpnt->dynamic_info[DT_PLTGOT] == 0)
 347                                 continue;
 348 #endif
 349                         /* OK, we have what we need - slip this one into the list. */
 350                         app_tpnt = _dl_add_elf_hash_table(_dl_progname, app_tpnt->loadaddr,
 351                                         app_tpnt->dynamic_info,
 352                                         DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr),
 353                                         ppnt->p_filesz);
 354                         _dl_loaded_modules->libtype = elf_executable;
 355                         _dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 356                         _dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
 357                         _dl_symbol_tables = rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
 358                         _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
 359                         rpnt->dyn = _dl_loaded_modules;
 360                         app_tpnt->rtld_flags = unlazy | RTLD_GLOBAL;
 361                         app_tpnt->usage_count++;
 362                         app_tpnt->symbol_scope = _dl_symbol_tables;
 363                         lpnt = (unsigned long *) (app_tpnt->dynamic_info[DT_PLTGOT]);
 364 #ifdef ALLOW_ZERO_PLTGOT
 365                         if (lpnt)
 366 #endif
 367                                 INIT_GOT(lpnt, _dl_loaded_modules);
 368                 }
 369
 370                 /* OK, fill this in - we did not have this before */
 371                 if (ppnt->p_type == PT_INTERP) {
 372                         char *ptmp;
 373
 374                         tpnt->libname = (char *) DL_RELOC_ADDR(app_tpnt->loadaddr, ppnt->p_vaddr);
 375
 376                         /* Store the path where the shared lib loader was found
 377                          * for later use
 378                          */
 379                         _dl_ldsopath = _dl_strdup(tpnt->libname);
 380                         ptmp = _dl_strrchr(_dl_ldsopath, '/');
 381                         if (ptmp != _dl_ldsopath)
 382                                 *ptmp = '\0';
 383
 384                         _dl_debug_early("Lib Loader: (%x) %s\n", DL_LOADADDR_BASE(tpnt->loadaddr), tpnt->libname);
 385                 }
 386         }
 387         app_tpnt->relro_addr = relro_addr;
 388         app_tpnt->relro_size = relro_size;
 389
 390 #ifdef __SUPPORT_LD_DEBUG__
 391         _dl_debug = _dl_getenv("LD_DEBUG", envp);
 392         if (_dl_debug) {
 393                 if (_dl_strstr(_dl_debug, "all")) {
 394                         _dl_debug_detail = _dl_debug_move = _dl_debug_symbols
 395                                 = _dl_debug_reloc = _dl_debug_bindings = _dl_debug_nofixups = (void*)1;
 396                 } else {
 397                         _dl_debug_detail   = _dl_strstr(_dl_debug, "detail");
 398                         _dl_debug_move     = _dl_strstr(_dl_debug, "move");
 399                         _dl_debug_symbols  = _dl_strstr(_dl_debug, "sym");
 400                         _dl_debug_reloc    = _dl_strstr(_dl_debug, "reloc");
 401                         _dl_debug_nofixups = _dl_strstr(_dl_debug, "nofix");
 402                         _dl_debug_bindings = _dl_strstr(_dl_debug, "bind");
 403                 }
 404         }
 405
 406         {
 407                 const char *dl_debug_output;
 408
 409                 dl_debug_output = _dl_getenv("LD_DEBUG_OUTPUT", envp);
 410
 411                 if (dl_debug_output) {
 412                         char tmp[22], *tmp1, *filename;
 413                         int len1, len2;
 414
 415                         _dl_memset(tmp, 0, sizeof(tmp));
 416                         tmp1 = _dl_simple_ltoa( tmp, (unsigned long)_dl_getpid());
 417
 418                         len1 = _dl_strlen(dl_debug_output);
 419                         len2 = _dl_strlen(tmp1);
 420
 421                         filename = _dl_malloc(len1+len2+2);
 422
 423                         if (filename) {
 424                                 _dl_strcpy (filename, dl_debug_output);
 425                                 filename[len1] = '.';
 426                                 _dl_strcpy (&filename[len1+1], tmp1);
 427
 428                                 _dl_debug_file= _dl_open(filename, O_WRONLY|O_CREAT, 0644);
 429                                 if (_dl_debug_file < 0) {
 430                                         _dl_debug_file = 2;
 431                                         _dl_dprintf(_dl_debug_file, "can't open file: '%s'\n",filename);
 432                                 }
 433                         }
 434                 }
 435         }
 436 #endif
 437
 438         if (_dl_getenv("LD_TRACE_LOADED_OBJECTS", envp) != NULL) {
 439                 trace_loaded_objects++;
 440         }
 441
 442 #ifndef __LDSO_LDD_SUPPORT__
 443         if (trace_loaded_objects) {
 444                 _dl_dprintf(_dl_debug_file, "Use the ldd provided by uClibc\n");
 445                 _dl_exit(1);
 446         }
 447 #endif
 448
 449         /*
 450          * OK, fix one more thing - set up debug_addr so it will point
 451          * to our chain.  Later we may need to fill in more fields, but this
 452          * should be enough for now.
 453          */
 454         debug_addr->r_map = (struct link_map *) _dl_loaded_modules;
 455         debug_addr->r_version = 1;
 456         debug_addr->r_ldbase = DL_LOADADDR_BASE(load_addr);
 457         debug_addr->r_brk = (unsigned long) &_dl_debug_state;
 458         _dl_debug_addr = debug_addr;
 459
 460         /* Notify the debugger we are in a consistant state */
 461         _dl_debug_addr->r_state = RT_CONSISTENT;
 462         _dl_debug_state();
 463
 464         /* OK, we now have the application in the list, and we have some
 465          * basic stuff in place.  Now search through the list for other shared
 466          * libraries that should be loaded, and insert them on the list in the
 467          * correct order.
 468          */
 469
 470         _dl_map_cache();
 471
 472         if (_dl_preload) {
 473                 char c, *str, *str2;
 474
 475                 str = _dl_preload;
 476                 while (*str == ':' || *str == ' ' || *str == '\t')
 477                         str++;
 478
 479                 while (*str) {
 480                         str2 = str;
 481                         while (*str2 && *str2 != ':' && *str2 != ' ' && *str2 != '\t')
 482                                 str2++;
 483                         c = *str2;
 484                         *str2 = '\0';
 485
 486                         if (!_dl_secure || _dl_strchr(str, '/') == NULL) {
 487                                 _dl_if_debug_dprint("\tfile='%s';  needed by '%s'\n", str, _dl_progname);
 488
 489                                 tpnt1 = _dl_load_shared_library(_dl_secure, &rpnt, NULL, str, trace_loaded_objects);
 490                                 if (!tpnt1) {
 491 #ifdef __LDSO_LDD_SUPPORT__
 492                                         if (trace_loaded_objects)
 493                                                 _dl_dprintf(1, "\t%s => not found\n", str);
 494                                         else
 495 #endif
 496                                         {
 497                                                 _dl_dprintf(_dl_debug_file, "%s: can't load " "library '%s'\n", _dl_progname, str);
 498                                                 _dl_exit(15);
 499                                         }
 500                                 } else {
 501                                         tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 502
 503                                         _dl_debug_early("Loading: (%x) %s\n", DL_LOADADDR_BASE(tpnt1->loadaddr), tpnt1->libname);
 504
 505 #ifdef __LDSO_LDD_SUPPORT__
 506                                         if (trace_loaded_objects &&
 507                                             tpnt1->usage_count == 1) {
 508                                                 /* This is a real hack to make
 509                                                  * ldd not print the library
 510                                                  * itself when run on a
 511                                                  * library.
 512                                                  */
 513                                                 if (_dl_strcmp(_dl_progname, str) != 0)
 514                                                         _dl_dprintf(1, "\t%s => %s (%x)\n", str, tpnt1->libname,
 515                                                                     DL_LOADADDR_BASE(tpnt1->loadaddr));
 516                                         }
 517 #endif
 518                                 }
 519                         }
 520
 521                         *str2 = c;
 522                         str = str2;
 523                         while (*str == ':' || *str == ' ' || *str == '\t')
 524                                 str++;
 525                 }
 526         }
 527
 528 #ifdef __LDSO_PRELOAD_FILE_SUPPORT__
 529         do {
 530                 struct stat st;
 531                 char *preload;
 532                 int fd;
 533                 char c, *cp, *cp2;
 534
 535                 if (_dl_stat(LDSO_PRELOAD, &st) || st.st_size == 0) {
 536                         break;
 537                 }
 538
 539                 if ((fd = _dl_open(LDSO_PRELOAD, O_RDONLY, 0)) < 0) {
 540                         _dl_dprintf(_dl_debug_file, "%s: can't open file '%s'\n",
 541                                     _dl_progname, LDSO_PRELOAD);
 542                         break;
 543                 }
 544
 545                 preload = (caddr_t) _dl_mmap(0, st.st_size + 1,
 546                                              PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
 547                 _dl_close(fd);
 548                 if (preload == (caddr_t) -1) {
 549                         _dl_dprintf(_dl_debug_file, "%s:%i: can't map '%s'\n",
 550                                     _dl_progname, __LINE__, LDSO_PRELOAD);
 551                         break;
 552                 }
 553
 554                 /* convert all separators and comments to spaces */
 555                 for (cp = preload; *cp; /*nada */ ) {
 556                         if (*cp == ':' || *cp == '\t' || *cp == '\n') {
 557                                 *cp++ = ' ';
 558                         } else if (*cp == '#') {
 559                                 do {
 560                                         *cp++ = ' ';
 561                                 } while (*cp != '\n' && *cp != '\0');
 562                         } else {
 563                                 cp++;
 564                         }
 565                 }
 566
 567                 /* find start of first library */
 568                 for (cp = preload; *cp && *cp == ' '; cp++)
 569                         /*nada */ ;
 570
 571                 while (*cp) {
 572                         /* find end of library */
 573                         for (cp2 = cp; *cp && *cp != ' '; cp++)
 574                                 /*nada */ ;
 575                         c = *cp;
 576                         *cp = '\0';
 577
 578                         _dl_if_debug_dprint("\tfile='%s';  needed by '%s'\n", cp2, _dl_progname);
 579
 580                         tpnt1 = _dl_load_shared_library(0, &rpnt, NULL, cp2, trace_loaded_objects);
 581                         if (!tpnt1) {
 582 #ifdef __LDSO_LDD_SUPPORT__
 583                                 if (trace_loaded_objects)
 584                                         _dl_dprintf(1, "\t%s => not found\n", cp2);
 585                                 else
 586 #endif
 587                                 {
 588                                         _dl_dprintf(_dl_debug_file, "%s: can't load library '%s'\n", _dl_progname, cp2);
 589                                         _dl_exit(15);
 590                                 }
 591                         } else {
 592                                 tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 593
 594                                 _dl_debug_early("Loading: (%x) %s\n", DL_LOADADDR_BASE(tpnt1->loadaddr), tpnt1->libname);
 595
 596 #ifdef __LDSO_LDD_SUPPORT__
 597                                 if (trace_loaded_objects &&
 598                                     tpnt1->usage_count == 1) {
 599                                         _dl_dprintf(1, "\t%s => %s (%x)\n",
 600                                                     cp2, tpnt1->libname,
 601                                                     DL_LOADADDR_BASE(tpnt1->loadaddr));
 602                                 }
 603 #endif
 604                         }
 605
 606                         /* find start of next library */
 607                         *cp = c;
 608                         for ( /*nada */ ; *cp && *cp == ' '; cp++)
 609                                 /*nada */ ;
 610                 }
 611
 612                 _dl_munmap(preload, st.st_size + 1);
 613         } while (0);
 614 #endif /* __LDSO_PRELOAD_FILE_SUPPORT__ */
 615
 616         nlist = 0;
 617         for (tcurr = _dl_loaded_modules; tcurr; tcurr = tcurr->next) {
 618                 ElfW(Dyn) *this_dpnt;
 619
 620                 nlist++;
 621                 for (this_dpnt = (ElfW(Dyn) *) tcurr->dynamic_addr; this_dpnt->d_tag; this_dpnt++) {
 622                         if (this_dpnt->d_tag == DT_NEEDED) {
 623                                 char *name;
 624                                 struct init_fini_list *tmp;
 625
 626                                 lpntstr = (char*) (tcurr->dynamic_info[DT_STRTAB] + this_dpnt->d_un.d_val);
 627                                 name = _dl_get_last_path_component(lpntstr);
 628                                 if (_dl_strcmp(name, UCLIBC_LDSO) == 0)
 629                                         continue;
 630
 631                                 _dl_if_debug_dprint("\tfile='%s';  needed by '%s'\n", lpntstr, _dl_progname);
 632
 633                                 if (!(tpnt1 = _dl_load_shared_library(0, &rpnt, tcurr, lpntstr, trace_loaded_objects))) {
 634 #ifdef __LDSO_LDD_SUPPORT__
 635                                         if (trace_loaded_objects) {
 636                                                 _dl_dprintf(1, "\t%s => not found\n", lpntstr);
 637                                                 continue;
 638                                         } else
 639 #endif
 640                                         {
 641                                                 _dl_dprintf(_dl_debug_file, "%s: can't load library '%s'\n", _dl_progname, lpntstr);
 642                                                 _dl_exit(16);
 643                                         }
 644                                 }
 645
 646                                 tmp = alloca(sizeof(struct init_fini_list)); /* Allocates on stack, no need to free this memory */
 647                                 tmp->tpnt = tpnt1;
 648                                 tmp->next = tcurr->init_fini;
 649                                 tcurr->init_fini = tmp;
 650
 651                                 tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 652
 653                                 _dl_debug_early("Loading: (%x) %s\n", DL_LOADADDR_BASE(tpnt1->loadaddr), tpnt1->libname);
 654
 655 #ifdef __LDSO_LDD_SUPPORT__
 656                                 if (trace_loaded_objects &&
 657                                     tpnt1->usage_count == 1) {
 658                                         _dl_dprintf(1, "\t%s => %s (%x)\n",
 659                                                     lpntstr, tpnt1->libname,
 660                                                     DL_LOADADDR_BASE(tpnt1->loadaddr));
 661                                 }
 662 #endif
 663                         }
 664                 }
 665         }
 666         _dl_unmap_cache();
 667
 668         --nlist; /* Exclude the application. */
 669         init_fini_list = _dl_malloc(nlist * sizeof(struct elf_resolve *));
 670         i = 0;
 671         for (tcurr = _dl_loaded_modules->next; tcurr; tcurr = tcurr->next) {
 672                 init_fini_list[i++] = tcurr;
 673         }
 674
 675         /* Sort the INIT/FINI list in dependency order. */
 676         for (tcurr = _dl_loaded_modules->next; tcurr; tcurr = tcurr->next) {
 677                 int j, k;
 678
 679                 for (j = 0; init_fini_list[j] != tcurr; ++j)
 680                         /* Empty */;
 681                 for (k = j + 1; k < nlist; ++k) {
 682                         struct init_fini_list *runp = init_fini_list[k]->init_fini;
 683
 684                         for (; runp; runp = runp->next) {
 685                                 if (runp->tpnt == tcurr) {
 686                                         struct elf_resolve *here = init_fini_list[k];
 687                                         _dl_if_debug_dprint("Move %s from pos %d to %d in INIT/FINI list\n", here->libname, k, j);
 688                                         for (i = (k - j); i; --i)
 689                                                 init_fini_list[i+j] = init_fini_list[i+j-1];
 690                                         init_fini_list[j] = here;
 691                                         ++j;
 692                                         break;
 693                                 }
 694                         }
 695                 }
 696         }
 697 #ifdef __SUPPORT_LD_DEBUG__
 698         if (_dl_debug) {
 699                 _dl_dprintf(_dl_debug_file, "\nINIT/FINI order and dependencies:\n");
 700                 for (i = 0; i < nlist; i++) {
 701                         struct init_fini_list *tmp;
 702
 703                         _dl_dprintf(_dl_debug_file, "lib: %s has deps:\n",
 704                                     init_fini_list[i]->libname);
 705                         tmp = init_fini_list[i]->init_fini;
 706                         for (; tmp; tmp = tmp->next)
 707                                 _dl_dprintf(_dl_debug_file, " %s ", tmp->tpnt->libname);
 708                         _dl_dprintf(_dl_debug_file, "\n");
 709                 }
 710         }
 711 #endif
 712
 713         /*
 714          * If the program interpreter is not in the module chain, add it.
 715          * This will be required for dlopen to be able to access the internal
 716          * functions in the dynamic linker and to relocate the interpreter
 717          * again once all libs are loaded.
 718          */
 719         if (tpnt) {
 720                 ElfW(Ehdr) *epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val;
 721                 ElfW(Phdr) *myppnt = (ElfW(Phdr) *) DL_RELOC_ADDR(load_addr, epnt->e_phoff);
 722                 int j;
 723
 724                 tpnt = _dl_add_elf_hash_table(tpnt->libname, load_addr,
 725                                               tpnt->dynamic_info,
 726                                               (unsigned long)tpnt->dynamic_addr,
 727                                               0);
 728
 729                 if (_dl_stat(tpnt->libname, &st) >= 0) {
 730                         tpnt->st_dev = st.st_dev;
 731                         tpnt->st_ino = st.st_ino;
 732                 }
 733                 tpnt->n_phent = epnt->e_phnum;
 734                 tpnt->ppnt = myppnt;
 735                 for (j = 0; j < epnt->e_phnum; j++, myppnt++) {
 736                         if (myppnt->p_type ==  PT_GNU_RELRO) {
 737                                 tpnt->relro_addr = myppnt->p_vaddr;
 738                                 tpnt->relro_size = myppnt->p_memsz;
 739                                 break;
 740                         }
 741                 }
 742                 tpnt->libtype = program_interpreter;
 743                 tpnt->usage_count++;
 744                 tpnt->symbol_scope = _dl_symbol_tables;
 745                 if (rpnt) {
 746                         rpnt->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
 747                         _dl_memset(rpnt->next, 0, sizeof(struct dyn_elf));
 748                         rpnt->next->prev = rpnt;
 749                         rpnt = rpnt->next;
 750                 } else {
 751                         rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
 752                         _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
 753                 }
 754                 rpnt->dyn = tpnt;
 755                 tpnt->rtld_flags = RTLD_NOW | RTLD_GLOBAL; /* Must not be LAZY */
 756 #ifdef RERELOCATE_LDSO
 757                 /* Only rerelocate functions for now. */
 758                 tpnt->init_flag = RELOCS_DONE;
 759                 lpnt = (unsigned long *) (tpnt->dynamic_info[DT_PLTGOT]);
 760 # ifdef ALLOW_ZERO_PLTGOT
 761                 if (tpnt->dynamic_info[DT_PLTGOT])
 762 # endif
 763                         INIT_GOT(lpnt, tpnt);
 764 #else
 765                 tpnt->init_flag = RELOCS_DONE | JMP_RELOCS_DONE;
 766 #endif
 767                 tpnt = NULL;
 768         }
 769
 770 #ifdef __LDSO_LDD_SUPPORT__
 771         /* End of the line for ldd.... */
 772         if (trace_loaded_objects) {
 773                 _dl_dprintf(1, "\t%s => %s (%x)\n",
 774                             rpnt->dyn->libname + _dl_strlen(_dl_ldsopath) + 1,
 775                             rpnt->dyn->libname, DL_LOADADDR_BASE(rpnt->dyn->loadaddr));
 776                 _dl_exit(0);
 777         }
 778 #endif
 779
 780         _dl_debug_early("Beginning relocation fixups\n");
 781
 782 #ifdef __mips__
 783         /*
 784          * Relocation of the GOT entries for MIPS have to be done
 785          * after all the libraries have been loaded.
 786          */
 787         _dl_perform_mips_global_got_relocations(_dl_loaded_modules, !unlazy);
 788 #endif
 789
 790         /*
 791          * OK, now all of the kids are tucked into bed in their proper
 792          * addresses.  Now we go through and look for REL and RELA records that
 793          * indicate fixups to the GOT tables.  We need to do this in reverse
 794          * order so that COPY directives work correctly.
 795          */
 796         if (_dl_symbol_tables)
 797                 if (_dl_fixup(_dl_symbol_tables, unlazy))
 798                         _dl_exit(-1);
 799
 800         for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 801                 if (tpnt->relro_size)
 802                         _dl_protect_relro (tpnt);
 803         }
 804
 805         /* OK, at this point things are pretty much ready to run.  Now we need
 806          * to touch up a few items that are required, and then we can let the
 807          * user application have at it.  Note that the dynamic linker itself
 808          * is not guaranteed to be fully dynamicly linked if we are using
 809          * ld.so.1, so we have to look up each symbol individually.
 810          */
 811
 812         _dl_envp = (unsigned long *) (intptr_t) _dl_find_hash("__environ", _dl_symbol_tables, NULL, 0);
 813         if (_dl_envp)
 814                 *_dl_envp = (unsigned long) envp;
 815
 816 #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
 817         {
 818                 unsigned int j;
 819                 ElfW(Phdr) *myppnt;
 820
 821                 /* We had to set the protections of all pages to R/W for
 822                  * dynamic linking.  Set text pages back to R/O.
 823                  */
 824                 for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 825                         for (myppnt = tpnt->ppnt, j = 0; j < tpnt->n_phent; j++, myppnt++) {
 826                                 if (myppnt->p_type == PT_LOAD && !(myppnt->p_flags & PF_W) && tpnt->dynamic_info[DT_TEXTREL]) {
 827                                         _dl_mprotect((void *) (DL_RELOC_ADDR(tpnt->loadaddr, myppnt->p_vaddr) & PAGE_ALIGN),
 828                                                         (myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz, LXFLAGS(myppnt->p_flags));
 829                                 }
 830                         }
 831                 }
 832
 833         }
 834 #endif
 835         /* Notify the debugger we have added some objects. */
 836         _dl_debug_addr->r_state = RT_ADD;
 837         _dl_debug_state();
 838
 839         /* Run pre-initialization functions for the executable.  */
 840         _dl_run_array_forward(_dl_loaded_modules->dynamic_info[DT_PREINIT_ARRAY],
 841                               _dl_loaded_modules->dynamic_info[DT_PREINIT_ARRAYSZ],
 842                               _dl_loaded_modules->loadaddr);
 843
 844         /* Run initialization functions for loaded objects.  For the
 845            main executable, they will be run from __uClibc_main.  */
 846         for (i = nlist; i; --i) {
 847                 tpnt = init_fini_list[i-1];
 848                 tpnt->init_fini = NULL; /* Clear, since alloca was used */
 849                 if (tpnt->init_flag & INIT_FUNCS_CALLED)
 850                         continue;
 851                 tpnt->init_flag |= INIT_FUNCS_CALLED;
 852
 853                 if (tpnt->dynamic_info[DT_INIT]) {
 854                         void (*dl_elf_func) (void);
 855
 856                         dl_elf_func = (void (*)(void)) DL_RELOC_ADDR(tpnt->loadaddr, tpnt->dynamic_info[DT_INIT]);
 857
 858                         _dl_if_debug_dprint("calling INIT: %s\n\n", tpnt->libname);
 859
 860                         DL_CALL_FUNC_AT_ADDR (dl_elf_func, tpnt->loadaddr, (void(*)(void)));
 861                 }
 862
 863                 _dl_run_init_array(tpnt);
 864         }
 865
 866         /* Find the real malloc function and make ldso functions use that from now on */
 867          _dl_malloc_function = (void* (*)(size_t)) (intptr_t) _dl_find_hash("malloc",
 868                          _dl_symbol_tables, NULL, ELF_RTYPE_CLASS_PLT);
 869
 870         /* Notify the debugger that all objects are now mapped in.  */
 871         _dl_debug_addr->r_state = RT_CONSISTENT;
 872         _dl_debug_state();
 873 }
 874
 875 char *_dl_getenv(const char *symbol, char **envp)
 876 {
 877         char *pnt;
 878         const char *pnt1;
 879
 880         while ((pnt = *envp++)) {
 881                 pnt1 = symbol;
 882                 while (*pnt && *pnt == *pnt1)
 883                         pnt1++, pnt++;
 884                 if (!*pnt || *pnt != '=' || *pnt1)
 885                         continue;
 886                 return pnt + 1;
 887         }
 888         return 0;
 889 }
 890
 891 void _dl_unsetenv(const char *symbol, char **envp)
 892 {
 893         char *pnt;
 894         const char *pnt1;
 895         char **newenvp = envp;
 896
 897         for (pnt = *envp; pnt; pnt = *++envp) {
 898                 pnt1 = symbol;
 899                 while (*pnt && *pnt == *pnt1)
 900                         pnt1++, pnt++;
 901                 if (!*pnt || *pnt != '=' || *pnt1)
 902                         *newenvp++ = *envp;
 903         }
 904         *newenvp++ = *envp;
 905         return;
 906 }
 907
 908 static int _dl_suid_ok(void)
 909 {
 910         __kernel_uid_t uid, euid;
 911         __kernel_gid_t gid, egid;
 912
 913         uid = _dl_getuid();
 914         euid = _dl_geteuid();
 915         gid = _dl_getgid();
 916         egid = _dl_getegid();
 917
 918         if (uid == euid && gid == egid) {
 919                 return 1;
 920         }
 921         return 0;
 922 }
 923
 924 void *_dl_malloc(int size)
 925 {
 926         void *retval;
 927
 928 #if 0
 929         _dl_debug_early("request for %d bytes\n", size);
 930 #endif
 931
 932         if (_dl_malloc_function)
 933                 return (*_dl_malloc_function) (size);
 934
 935         if (_dl_malloc_addr - _dl_mmap_zero + (unsigned)size > _dl_pagesize) {
 936                 _dl_debug_early("mmapping more memory\n");
 937                 _dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, size,
 938                                 PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 939                 if (_dl_mmap_check_error(_dl_mmap_zero)) {
 940                         _dl_dprintf(_dl_debug_file, "%s: mmap of a spare page failed!\n", _dl_progname);
 941                         _dl_exit(20);
 942                 }
 943         }
 944         retval = _dl_malloc_addr;
 945         _dl_malloc_addr += size;
 946
 947         /*
 948          * Align memory to 4 byte boundary.  Some platforms require this,
 949          * others simply get better performance.
 950          */
 951         _dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + 3) & ~(3));
 952         return retval;
 953 }
 954
 955 #include "dl-hash.c"
 956 #include "dl-elf.c"