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) 2000-2004 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 {
  79 }
  80
  81 static unsigned char *_dl_malloc_addr = 0;      /* Lets _dl_malloc use the already allocated memory page */
  82 static unsigned char *_dl_mmap_zero   = 0;      /* Also used by _dl_malloc */
  83
  84 static struct elf_resolve **init_fini_list;
  85 static unsigned int nlist; /* # items in init_fini_list */
  86 extern void _start(void);
  87
  88 #ifdef __UCLIBC_HAS_SSP__
  89 #include <dl-osinfo.h>
  90 #ifndef THREAD_SET_STACK_GUARD
  91 /* Only exported for architectures that don't store the stack guard canary
  92  * in local thread area.  */
  93 uintptr_t __stack_chk_guard attribute_relro;
  94 strong_alias(__stack_chk_guard,__guard)
  95 #endif
  96 #endif
  97
  98 static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void)
  99 {
 100         int i;
 101         struct elf_resolve * tpnt;
 102
 103         for (i = 0; i < nlist; ++i) {
 104                 tpnt = init_fini_list[i];
 105                 if (tpnt->init_flag & FINI_FUNCS_CALLED)
 106                         continue;
 107                 tpnt->init_flag |= FINI_FUNCS_CALLED;
 108                 if (tpnt->dynamic_info[DT_FINI]) {
 109                         void (*dl_elf_func) (void);
 110
 111                         dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
 112                         _dl_if_debug_dprint("\ncalling FINI: %s\n\n", tpnt->libname);
 113                         (*dl_elf_func) ();
 114                 }
 115         }
 116 }
 117
 118 void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
 119                           ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp,
 120                           char **argv)
 121 {
 122         ElfW(Phdr) *ppnt;
 123         ElfW(Dyn) *dpnt;
 124         char *lpntstr;
 125         unsigned int i;
 126         int unlazy = 0, trace_loaded_objects = 0;
 127         struct dyn_elf *rpnt;
 128         struct elf_resolve *tcurr;
 129         struct elf_resolve *tpnt1;
 130         struct elf_resolve app_tpnt_tmp;
 131         struct elf_resolve *app_tpnt = &app_tpnt_tmp;
 132         struct r_debug *debug_addr;
 133         unsigned long *lpnt;
 134         unsigned long *_dl_envp;                /* The environment address */
 135         ElfW(Addr) relro_addr = 0;
 136         size_t relro_size = 0;
 137
 138         /* Wahoo!!! We managed to make a function call!  Get malloc
 139          * setup so we can use _dl_dprintf() to print debug noise
 140          * instead of the SEND_STDERR macros used in dl-startup.c */
 141
 142         _dl_memset(app_tpnt, 0x00, sizeof(*app_tpnt));
 143
 144         /* Store the page size for later use */
 145         _dl_pagesize = (auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE;
 146         /* Make it so _dl_malloc can use the page of memory we have already
 147          * allocated.  We shouldn't need to grab any more memory.  This must
 148          * be first since things like _dl_dprintf() use _dl_malloc()...
 149          */
 150         _dl_malloc_addr = (unsigned char *)_dl_pagesize;
 151         _dl_mmap_zero = 0;
 152
 153         /* Wahoo!!! */
 154         _dl_debug_early("Cool, ldso survived making function calls\n");
 155
 156         /* Now we have done the mandatory linking of some things.  We are now
 157          * free to start using global variables, since these things have all
 158          * been fixed up by now.  Still no function calls outside of this
 159          * library, since the dynamic resolver is not yet ready.
 160          */
 161         if (argv[0]) {
 162                 _dl_progname = argv[0];
 163         }
 164
 165         if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) {
 166                 _dl_dprintf(_dl_debug_file, "Standalone execution is not supported yet\n");
 167                 _dl_exit(1);
 168         }
 169
 170         /* Start to build the tables of the modules that are required for
 171          * this beast to run.  We start with the basic executable, and then
 172          * go from there.  Eventually we will run across ourself, and we
 173          * will need to properly deal with that as well.
 174          */
 175         rpnt = NULL;
 176         if (_dl_getenv("LD_BIND_NOW", envp))
 177                 unlazy = RTLD_NOW;
 178
 179         /* Now we need to figure out what kind of options are selected.
 180          * Note that for SUID programs we ignore the settings in
 181          * LD_LIBRARY_PATH.
 182          */
 183         if ((auxvt[AT_UID].a_un.a_val == (size_t)-1 && _dl_suid_ok()) ||
 184             (auxvt[AT_UID].a_un.a_val != (size_t)-1 &&
 185              auxvt[AT_UID].a_un.a_val == auxvt[AT_EUID].a_un.a_val &&
 186              auxvt[AT_GID].a_un.a_val == auxvt[AT_EGID].a_un.a_val)) {
 187                 _dl_secure = 0;
 188                 _dl_preload = _dl_getenv("LD_PRELOAD", envp);
 189                 _dl_library_path = _dl_getenv("LD_LIBRARY_PATH", envp);
 190         } else {
 191                 static const char unsecure_envvars[] =
 192 #ifdef EXTRA_UNSECURE_ENVVARS
 193                         EXTRA_UNSECURE_ENVVARS
 194 #endif
 195                         UNSECURE_ENVVARS;
 196                 const char *nextp;
 197                 _dl_secure = 1;
 198
 199                 nextp = unsecure_envvars;
 200                 do {
 201                         _dl_unsetenv (nextp, envp);
 202                         /* We could use rawmemchr but this need not be fast.  */
 203                         nextp = (char *) _dl_strchr(nextp, '\0') + 1;
 204                 } while (*nextp != '\0');
 205                 _dl_preload = NULL;
 206                 _dl_library_path = NULL;
 207                 /* SUID binaries can be exploited if they do LAZY relocation. */
 208                 unlazy = RTLD_NOW;
 209         }
 210
 211         /* sjhill: your TLS init should go before this */
 212 #ifdef __UCLIBC_HAS_SSP__
 213         /* Set up the stack checker's canary.  */
 214         uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard ();
 215 # ifdef THREAD_SET_STACK_GUARD
 216         THREAD_SET_STACK_GUARD (stack_chk_guard);
 217 # else
 218         __stack_chk_guard = stack_chk_guard;
 219 # endif
 220 #endif
 221
 222         /* At this point we are now free to examine the user application,
 223          * and figure out which libraries are supposed to be called.  Until
 224          * we have this list, we will not be completely ready for dynamic
 225          * linking.
 226          */
 227
 228         /* Find the runtime load address of the main executable.  This may be
 229          * different from what the ELF header says for ET_DYN/PIE executables.
 230          */
 231         {
 232                 unsigned int i;
 233                 ElfW(Phdr) *ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 234
 235                 for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++)
 236                         if (ppnt->p_type == PT_PHDR) {
 237                                 app_tpnt->loadaddr = (ElfW(Addr)) (auxvt[AT_PHDR].a_un.a_val - ppnt->p_vaddr);
 238                                 break;
 239                         }
 240
 241                 if (app_tpnt->loadaddr)
 242                         _dl_debug_early("Position Independent Executable: "
 243                                         "app_tpnt->loadaddr=%x\n", app_tpnt->loadaddr);
 244         }
 245
 246         /*
 247          * This is used by gdb to locate the chain of shared libraries that are
 248          * currently loaded.
 249          */
 250         debug_addr = _dl_malloc(sizeof(struct r_debug));
 251         _dl_memset(debug_addr, 0, sizeof(struct r_debug));
 252
 253         ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 254         for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
 255                 if (ppnt->p_type == PT_GNU_RELRO) {
 256                         relro_addr = ppnt->p_vaddr;
 257                         relro_size = ppnt->p_memsz;
 258                 }
 259                 if (ppnt->p_type == PT_DYNAMIC) {
 260                         dpnt = (ElfW(Dyn) *) (ppnt->p_vaddr + app_tpnt->loadaddr);
 261                         _dl_parse_dynamic_info(dpnt, app_tpnt->dynamic_info, debug_addr, app_tpnt->loadaddr);
 262 #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
 263                         /* Ugly, ugly.  We need to call mprotect to change the
 264                          * protection of the text pages so that we can do the
 265                          * dynamic linking.  We can set the protection back
 266                          * again once we are done.
 267                          */
 268                         _dl_debug_early("calling mprotect on the application program\n");
 269                         /* Now cover the application program. */
 270                         if (app_tpnt->dynamic_info[DT_TEXTREL]) {
 271                                 ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 272                                 for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
 273                                         if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W))
 274                                                 _dl_mprotect((void *) ((ppnt->p_vaddr + app_tpnt->loadaddr) & PAGE_ALIGN),
 275                                                              ((ppnt->p_vaddr + app_tpnt->loadaddr) & ADDR_ALIGN) +
 276                                                              (unsigned long) ppnt->p_filesz,
 277                                                              PROT_READ | PROT_WRITE | PROT_EXEC);
 278                                 }
 279                         }
 280 #endif
 281
 282 #ifndef ALLOW_ZERO_PLTGOT
 283                         /* make sure it's really there. */
 284                         if (app_tpnt->dynamic_info[DT_PLTGOT] == 0)
 285                                 continue;
 286 #endif
 287                         /* OK, we have what we need - slip this one into the list. */
 288                         app_tpnt = _dl_add_elf_hash_table(_dl_progname, (char *)app_tpnt->loadaddr,
 289                                         app_tpnt->dynamic_info, ppnt->p_vaddr + app_tpnt->loadaddr, ppnt->p_filesz);
 290                         _dl_loaded_modules->libtype = elf_executable;
 291                         _dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
 292                         _dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
 293                         _dl_symbol_tables = rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
 294                         _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
 295                         rpnt->dyn = _dl_loaded_modules;
 296                         app_tpnt->rtld_flags = unlazy | RTLD_GLOBAL;
 297                         app_tpnt->usage_count++;
 298                         app_tpnt->symbol_scope = _dl_symbol_tables;
 299                         lpnt = (unsigned long *) (app_tpnt->dynamic_info[DT_PLTGOT]);
 300 #ifdef ALLOW_ZERO_PLTGOT
 301                         if (lpnt)
 302 #endif
 303                                 INIT_GOT(lpnt, _dl_loaded_modules);
 304                 }
 305
 306                 /* OK, fill this in - we did not have this before */
 307                 if (ppnt->p_type == PT_INTERP) {
 308                         char *ptmp;
 309
 310                         tpnt->libname = (char *) ppnt->p_vaddr + app_tpnt->loadaddr;
 311
 312                         /* Store the path where the shared lib loader was found
 313                          * for later use
 314                          */
 315                         _dl_ldsopath = _dl_strdup(tpnt->libname);
 316                         ptmp = _dl_strrchr(_dl_ldsopath, '/');
 317                         if (ptmp != _dl_ldsopath)
 318                                 *ptmp = '\0';
 319
 320                         _dl_debug_early("Lib Loader: (%x) %s\n", tpnt->loadaddr, tpnt->libname);
 321                 }
 322         }
 323         app_tpnt->relro_addr = relro_addr;
 324         app_tpnt->relro_size = relro_size;
 325
 326 #ifdef __SUPPORT_LD_DEBUG__
 327         _dl_debug = _dl_getenv("LD_DEBUG", envp);
 328         if (_dl_debug) {
 329                 if (_dl_strstr(_dl_debug, "all")) {
 330                         _dl_debug_detail = _dl_debug_move = _dl_debug_symbols
 331                                 = _dl_debug_reloc = _dl_debug_bindings = _dl_debug_nofixups = (void*)1;
 332                 } else {
 333                         _dl_debug_detail   = _dl_strstr(_dl_debug, "detail");
 334                         _dl_debug_move     = _dl_strstr(_dl_debug, "move");
 335                         _dl_debug_symbols  = _dl_strstr(_dl_debug, "sym");
 336                         _dl_debug_reloc    = _dl_strstr(_dl_debug, "reloc");
 337                         _dl_debug_nofixups = _dl_strstr(_dl_debug, "nofix");
 338                         _dl_debug_bindings = _dl_strstr(_dl_debug, "bind");
 339                 }
 340         }
 341
 342         {
 343                 const char *dl_debug_output;
 344
 345                 dl_debug_output = _dl_getenv("LD_DEBUG_OUTPUT", envp);
 346
 347                 if (dl_debug_output) {
 348                         char tmp[22], *tmp1, *filename;
 349                         int len1, len2;
 350
 351                         _dl_memset(tmp, 0, sizeof(tmp));
 352                         tmp1 = _dl_simple_ltoa( tmp, (unsigned long)_dl_getpid());
 353
 354                         len1 = _dl_strlen(dl_debug_output);
 355                         len2 = _dl_strlen(tmp1);
 356
 357                         filename = _dl_malloc(len1+len2+2);
 358
 359                         if (filename) {
 360                                 _dl_strcpy (filename, dl_debug_output);
 361                                 filename[len1] = '.';
 362                                 _dl_strcpy (&filename[len1+1], tmp1);
 363
 364                                 _dl_debug_file= _dl_open(filename, O_WRONLY|O_CREAT, 0644);
 365                                 if (_dl_debug_file < 0) {
 366                                         _dl_debug_file = 2;
 367                                         _dl_dprintf(_dl_debug_file, "can't open file: '%s'\n",filename);
 368                                 }
 369                         }
 370                 }
 371         }
 372 #endif
 373
 374         if (_dl_getenv("LD_TRACE_LOADED_OBJECTS", envp) != NULL) {
 375                 trace_loaded_objects++;
 376         }
 377
 378 #ifndef __LDSO_LDD_SUPPORT__
 379         if (trace_loaded_objects) {
 380                 _dl_dprintf(_dl_debug_file, "Use the ldd provided by uClibc\n");
 381                 _dl_exit(1);
 382         }
 383 #endif
 384
 385         /*
 386          * OK, fix one more thing - set up debug_addr so it will point
 387          * to our chain.  Later we may need to fill in more fields, but this
 388          * should be enough for now.
 389          */
 390         debug_addr->r_map = (struct link_map *) _dl_loaded_modules;
 391         debug_addr->r_version = 1;
 392         debug_addr->r_ldbase = load_addr;
 393         debug_addr->r_brk = (unsigned long) &_dl_debug_state;
 394         _dl_debug_addr = debug_addr;
 395
 396         /* Notify the debugger we are in a consistant state */
 397         _dl_debug_addr->r_state = RT_CONSISTENT;
 398         _dl_debug_state();
 399
 400         /* OK, we now have the application in the list, and we have some
 401          * basic stuff in place.  Now search through the list for other shared
 402          * libraries that should be loaded, and insert them on the list in the
 403          * correct order.
 404          */
 405
 406         _dl_map_cache();
 407
 408         if (_dl_preload) {
 409                 char c, *str, *str2;
 410
 411                 str = _dl_preload;
 412                 while (*str == ':' || *str == ' ' || *str == '\t')
 413                         str++;
 414
 415                 while (*str) {
 416                         str2 = str;
 417                         while (*str2 && *str2 != ':' && *str2 != ' ' && *str2 != '\t')
 418                                 str2++;
 419                         c = *str2;
 420                         *str2 = '\0';
 421
 422                         if (!_dl_secure || _dl_strchr(str, '/') == NULL) {
 423                                 _dl_if_debug_dprint("\tfile='%s';  needed by '%s'\n", str, _dl_progname);
 424
 425                                 tpnt1 = _dl_load_shared_library(_dl_secure, &rpnt, NULL, str, trace_loaded_objects);
 426                                 if (!tpnt1) {
 427 #ifdef __LDSO_LDD_SUPPORT__
 428                                         if (trace_loaded_objects)
 429                                                 _dl_dprintf(1, "\t%s => not found\n", str);
 430                                         else
 431 #endif
 432                                         {
 433                                                 _dl_dprintf(_dl_debug_file, "%s: can't load " "library '%s'\n", _dl_progname, str);
 434                                                 _dl_exit(15);
 435                                         }
 436                                 } else {
 437                                         tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 438
 439                                         _dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
 440
 441 #ifdef __LDSO_LDD_SUPPORT__
 442                                         if (trace_loaded_objects &&
 443                                             tpnt1->usage_count == 1) {
 444                                                 /* This is a real hack to make
 445                                                  * ldd not print the library
 446                                                  * itself when run on a
 447                                                  * library.
 448                                                  */
 449                                                 if (_dl_strcmp(_dl_progname, str) != 0)
 450                                                         _dl_dprintf(1, "\t%s => %s (%x)\n", str, tpnt1->libname,
 451                                                                     tpnt1->loadaddr);
 452                                         }
 453 #endif
 454                                 }
 455                         }
 456
 457                         *str2 = c;
 458                         str = str2;
 459                         while (*str == ':' || *str == ' ' || *str == '\t')
 460                                 str++;
 461                 }
 462         }
 463
 464 #ifdef __LDSO_PRELOAD_FILE_SUPPORT__
 465         do {
 466                 struct stat st;
 467                 char *preload;
 468                 int fd;
 469                 char c, *cp, *cp2;
 470
 471                 if (_dl_stat(LDSO_PRELOAD, &st) || st.st_size == 0) {
 472                         break;
 473                 }
 474
 475                 if ((fd = _dl_open(LDSO_PRELOAD, O_RDONLY, 0)) < 0) {
 476                         _dl_dprintf(_dl_debug_file, "%s: can't open file '%s'\n",
 477                                     _dl_progname, LDSO_PRELOAD);
 478                         break;
 479                 }
 480
 481                 preload = (caddr_t) _dl_mmap(0, st.st_size + 1,
 482                                              PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
 483                 _dl_close(fd);
 484                 if (preload == (caddr_t) -1) {
 485                         _dl_dprintf(_dl_debug_file, "%s: can't map file '%s'\n",
 486                                     _dl_progname, LDSO_PRELOAD);
 487                         break;
 488                 }
 489
 490                 /* convert all separators and comments to spaces */
 491                 for (cp = preload; *cp; /*nada */ ) {
 492                         if (*cp == ':' || *cp == '\t' || *cp == '\n') {
 493                                 *cp++ = ' ';
 494                         } else if (*cp == '#') {
 495                                 do {
 496                                         *cp++ = ' ';
 497                                 } while (*cp != '\n' && *cp != '\0');
 498                         } else {
 499                                 cp++;
 500                         }
 501                 }
 502
 503                 /* find start of first library */
 504                 for (cp = preload; *cp && *cp == ' '; cp++)
 505                         /*nada */ ;
 506
 507                 while (*cp) {
 508                         /* find end of library */
 509                         for (cp2 = cp; *cp && *cp != ' '; cp++)
 510                                 /*nada */ ;
 511                         c = *cp;
 512                         *cp = '\0';
 513
 514                         _dl_if_debug_dprint("\tfile='%s';  needed by '%s'\n", cp2, _dl_progname);
 515
 516                         tpnt1 = _dl_load_shared_library(0, &rpnt, NULL, cp2, trace_loaded_objects);
 517                         if (!tpnt1) {
 518 #ifdef __LDSO_LDD_SUPPORT__
 519                                 if (trace_loaded_objects)
 520                                         _dl_dprintf(1, "\t%s => not found\n", cp2);
 521                                 else
 522 #endif
 523                                 {
 524                                         _dl_dprintf(_dl_debug_file, "%s: can't load library '%s'\n", _dl_progname, cp2);
 525                                         _dl_exit(15);
 526                                 }
 527                         } else {
 528                                 tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 529
 530                                 _dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
 531
 532 #ifdef __LDSO_LDD_SUPPORT__
 533                                 if (trace_loaded_objects &&
 534                                     tpnt1->usage_count == 1) {
 535                                         _dl_dprintf(1, "\t%s => %s (%x)\n",
 536                                                     cp2, tpnt1->libname,
 537                                                     (unsigned)tpnt1->loadaddr);
 538                                 }
 539 #endif
 540                         }
 541
 542                         /* find start of next library */
 543                         *cp = c;
 544                         for ( /*nada */ ; *cp && *cp == ' '; cp++)
 545                                 /*nada */ ;
 546                 }
 547
 548                 _dl_munmap(preload, st.st_size + 1);
 549         } while (0);
 550 #endif /* __LDSO_PRELOAD_FILE_SUPPORT__ */
 551
 552         nlist = 0;
 553         for (tcurr = _dl_loaded_modules; tcurr; tcurr = tcurr->next) {
 554                 ElfW(Dyn) *dpnt;
 555
 556                 nlist++;
 557                 for (dpnt = (ElfW(Dyn) *) tcurr->dynamic_addr; dpnt->d_tag; dpnt++) {
 558                         if (dpnt->d_tag == DT_NEEDED) {
 559                                 char *name;
 560                                 struct init_fini_list *tmp;
 561
 562                                 lpntstr = (char*) (tcurr->dynamic_info[DT_STRTAB] + dpnt->d_un.d_val);
 563                                 name = _dl_get_last_path_component(lpntstr);
 564                                 if (_dl_strcmp(name, UCLIBC_LDSO) == 0)
 565                                         continue;
 566
 567                                 _dl_if_debug_dprint("\tfile='%s';  needed by '%s'\n", lpntstr, _dl_progname);
 568
 569                                 if (!(tpnt1 = _dl_load_shared_library(0, &rpnt, tcurr, lpntstr, trace_loaded_objects))) {
 570 #ifdef __LDSO_LDD_SUPPORT__
 571                                         if (trace_loaded_objects) {
 572                                                 _dl_dprintf(1, "\t%s => not found\n", lpntstr);
 573                                                 continue;
 574                                         } else
 575 #endif
 576                                         {
 577                                                 _dl_dprintf(_dl_debug_file, "%s: can't load library '%s'\n", _dl_progname, lpntstr);
 578                                                 _dl_exit(16);
 579                                         }
 580                                 }
 581
 582                                 tmp = alloca(sizeof(struct init_fini_list)); /* Allocates on stack, no need to free this memory */
 583                                 tmp->tpnt = tpnt1;
 584                                 tmp->next = tcurr->init_fini;
 585                                 tcurr->init_fini = tmp;
 586
 587                                 tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
 588
 589                                 _dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
 590
 591 #ifdef __LDSO_LDD_SUPPORT__
 592                                 if (trace_loaded_objects &&
 593                                     tpnt1->usage_count == 1) {
 594                                         _dl_dprintf(1, "\t%s => %s (%x)\n",
 595                                                     lpntstr, tpnt1->libname,
 596                                                     (unsigned)tpnt1->loadaddr);
 597                                 }
 598 #endif
 599                         }
 600                 }
 601         }
 602         _dl_unmap_cache();
 603
 604         --nlist; /* Exclude the application. */
 605         init_fini_list = _dl_malloc(nlist * sizeof(struct elf_resolve *));
 606         i = 0;
 607         for (tcurr = _dl_loaded_modules->next; tcurr; tcurr = tcurr->next) {
 608                 init_fini_list[i++] = tcurr;
 609         }
 610
 611         /* Sort the INIT/FINI list in dependency order. */
 612         for (tcurr = _dl_loaded_modules->next; tcurr; tcurr = tcurr->next) {
 613                 int j, k;
 614
 615                 for (j = 0; init_fini_list[j] != tcurr; ++j)
 616                         /* Empty */;
 617                 for (k = j + 1; k < nlist; ++k) {
 618                         struct init_fini_list *runp = init_fini_list[k]->init_fini;
 619
 620                         for (; runp; runp = runp->next) {
 621                                 if (runp->tpnt == tcurr) {
 622                                         struct elf_resolve *here = init_fini_list[k];
 623                                         _dl_if_debug_dprint("Move %s from pos %d to %d in INIT/FINI list\n", here->libname, k, j);
 624                                         for (i = (k - j); i; --i)
 625                                                 init_fini_list[i+j] = init_fini_list[i+j-1];
 626                                         init_fini_list[j] = here;
 627                                         ++j;
 628                                         break;
 629                                 }
 630                         }
 631                 }
 632         }
 633 #ifdef __SUPPORT_LD_DEBUG__
 634         if(_dl_debug) {
 635                 _dl_dprintf(_dl_debug_file, "\nINIT/FINI order and dependencies:\n");
 636                 for (i = 0; i < nlist; i++) {
 637                         struct init_fini_list *tmp;
 638
 639                         _dl_dprintf(_dl_debug_file, "lib: %s has deps:\n",
 640                                     init_fini_list[i]->libname);
 641                         tmp = init_fini_list[i]->init_fini;
 642                         for (; tmp; tmp = tmp->next)
 643                                 _dl_dprintf(_dl_debug_file, " %s ", tmp->tpnt->libname);
 644                         _dl_dprintf(_dl_debug_file, "\n");
 645                 }
 646         }
 647 #endif
 648
 649         /*
 650          * If the program interpreter is not in the module chain, add it.
 651          * This will be required for dlopen to be able to access the internal
 652          * functions in the dynamic linker and to relocate the interpreter
 653          * again once all libs are loaded.
 654          */
 655         if (tpnt) {
 656                 ElfW(Ehdr) *epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val;
 657                 ElfW(Phdr) *myppnt = (ElfW(Phdr) *) (load_addr + epnt->e_phoff);
 658                 int j;
 659
 660                 tpnt = _dl_add_elf_hash_table(tpnt->libname, (char *)load_addr,
 661                                               tpnt->dynamic_info,
 662                                               (unsigned long)tpnt->dynamic_addr,
 663                                               0);
 664
 665                 tpnt->n_phent = epnt->e_phnum;
 666                 tpnt->ppnt = myppnt;
 667                 for (j = 0; j < epnt->e_phnum; j++, myppnt++) {
 668                         if (myppnt->p_type ==  PT_GNU_RELRO) {
 669                                 tpnt->relro_addr = myppnt->p_vaddr;
 670                                 tpnt->relro_size = myppnt->p_memsz;
 671                                 break;
 672                         }
 673                 }
 674                 tpnt->libtype = program_interpreter;
 675                 tpnt->usage_count++;
 676                 tpnt->symbol_scope = _dl_symbol_tables;
 677                 if (rpnt) {
 678                         rpnt->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
 679                         _dl_memset(rpnt->next, 0, sizeof(struct dyn_elf));
 680                         rpnt->next->prev = rpnt;
 681                         rpnt = rpnt->next;
 682                 } else {
 683                         rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
 684                         _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
 685                 }
 686                 rpnt->dyn = tpnt;
 687                 tpnt->rtld_flags = RTLD_NOW | RTLD_GLOBAL; /* Must not be LAZY */
 688 #ifdef RERELOCATE_LDSO
 689                 /* Only rerelocate functions for now. */
 690                 tpnt->init_flag = RELOCS_DONE;
 691                 lpnt = (unsigned long *) (tpnt->dynamic_info[DT_PLTGOT]);
 692 # ifdef ALLOW_ZERO_PLTGOT
 693                 if (tpnt->dynamic_info[DT_PLTGOT])
 694 # endif
 695                         INIT_GOT(lpnt, tpnt);
 696 #else
 697                 tpnt->init_flag = RELOCS_DONE | JMP_RELOCS_DONE;
 698 #endif
 699                 tpnt = NULL;
 700         }
 701
 702 #ifdef __LDSO_LDD_SUPPORT__
 703         /* End of the line for ldd.... */
 704         if (trace_loaded_objects) {
 705                 _dl_dprintf(1, "\t%s => %s (%x)\n",
 706                             rpnt->dyn->libname + _dl_strlen(_dl_ldsopath) + 1,
 707                             rpnt->dyn->libname, rpnt->dyn->loadaddr);
 708                 _dl_exit(0);
 709         }
 710 #endif
 711
 712         _dl_debug_early("Beginning relocation fixups\n");
 713
 714 #ifdef __mips__
 715         /*
 716          * Relocation of the GOT entries for MIPS have to be done
 717          * after all the libraries have been loaded.
 718          */
 719         _dl_perform_mips_global_got_relocations(_dl_loaded_modules, !unlazy);
 720 #endif
 721
 722         /*
 723          * OK, now all of the kids are tucked into bed in their proper
 724          * addresses.  Now we go through and look for REL and RELA records that
 725          * indicate fixups to the GOT tables.  We need to do this in reverse
 726          * order so that COPY directives work correctly.
 727          */
 728         if (_dl_symbol_tables)
 729                 if (_dl_fixup(_dl_symbol_tables, unlazy))
 730                         _dl_exit(-1);
 731
 732         for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 733                 if (tpnt->relro_size)
 734                         _dl_protect_relro (tpnt);
 735         }
 736
 737         /* OK, at this point things are pretty much ready to run.  Now we need
 738          * to touch up a few items that are required, and then we can let the
 739          * user application have at it.  Note that the dynamic linker itself
 740          * is not guaranteed to be fully dynamicly linked if we are using
 741          * ld.so.1, so we have to look up each symbol individually.
 742          */
 743
 744         _dl_envp = (unsigned long *) (intptr_t) _dl_find_hash("__environ", _dl_symbol_tables, NULL, 0);
 745         if (_dl_envp)
 746                 *_dl_envp = (unsigned long) envp;
 747
 748 #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
 749         {
 750                 unsigned int j;
 751                 ElfW(Phdr) *myppnt;
 752
 753                 /* We had to set the protections of all pages to R/W for
 754                  * dynamic linking.  Set text pages back to R/O.
 755                  */
 756                 for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
 757                         for (myppnt = tpnt->ppnt, j = 0; j < tpnt->n_phent; j++, myppnt++) {
 758                                 if (myppnt->p_type == PT_LOAD && !(myppnt->p_flags & PF_W) && tpnt->dynamic_info[DT_TEXTREL]) {
 759                                         _dl_mprotect((void *) (tpnt->loadaddr + (myppnt->p_vaddr & PAGE_ALIGN)),
 760                                                         (myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz, LXFLAGS(myppnt->p_flags));
 761                                 }
 762                         }
 763                 }
 764
 765         }
 766 #endif
 767         /* Notify the debugger we have added some objects. */
 768         _dl_debug_addr->r_state = RT_ADD;
 769         _dl_debug_state();
 770         for (i = nlist; i; --i) {
 771                 tpnt = init_fini_list[i-1];
 772                 tpnt->init_fini = NULL; /* Clear, since alloca was used */
 773                 if (tpnt->init_flag & INIT_FUNCS_CALLED)
 774                         continue;
 775                 tpnt->init_flag |= INIT_FUNCS_CALLED;
 776
 777                 if (tpnt->dynamic_info[DT_INIT]) {
 778                         void (*dl_elf_func) (void);
 779
 780                         dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
 781
 782                         _dl_if_debug_dprint("calling INIT: %s\n\n", tpnt->libname);
 783
 784                         (*dl_elf_func) ();
 785                 }
 786         }
 787
 788         /* Find the real malloc function and make ldso functions use that from now on */
 789          _dl_malloc_function = (void* (*)(size_t)) (intptr_t) _dl_find_hash("malloc",
 790                          _dl_symbol_tables, NULL, ELF_RTYPE_CLASS_PLT);
 791
 792         /* Notify the debugger that all objects are now mapped in.  */
 793         _dl_debug_addr->r_state = RT_CONSISTENT;
 794         _dl_debug_state();
 795 }
 796
 797 char *_dl_getenv(const char *symbol, char **envp)
 798 {
 799         char *pnt;
 800         const char *pnt1;
 801
 802         while ((pnt = *envp++)) {
 803                 pnt1 = symbol;
 804                 while (*pnt && *pnt == *pnt1)
 805                         pnt1++, pnt++;
 806                 if (!*pnt || *pnt != '=' || *pnt1)
 807                         continue;
 808                 return pnt + 1;
 809         }
 810         return 0;
 811 }
 812
 813 void _dl_unsetenv(const char *symbol, char **envp)
 814 {
 815         char *pnt;
 816         const char *pnt1;
 817         char **newenvp = envp;
 818
 819         for (pnt = *envp; pnt; pnt = *++envp) {
 820                 pnt1 = symbol;
 821                 while (*pnt && *pnt == *pnt1)
 822                         pnt1++, pnt++;
 823                 if (!*pnt || *pnt != '=' || *pnt1)
 824                         *newenvp++ = *envp;
 825         }
 826         *newenvp++ = *envp;
 827         return;
 828 }
 829
 830 static int _dl_suid_ok(void)
 831 {
 832         __kernel_uid_t uid, euid;
 833         __kernel_gid_t gid, egid;
 834
 835         uid = _dl_getuid();
 836         euid = _dl_geteuid();
 837         gid = _dl_getgid();
 838         egid = _dl_getegid();
 839
 840         if(uid == euid && gid == egid) {
 841                 return 1;
 842         }
 843         return 0;
 844 }
 845
 846 void *_dl_malloc(int size)
 847 {
 848         void *retval;
 849
 850 #if 0
 851         _dl_debug_early("request for %d bytes\n", size);
 852 #endif
 853
 854         if (_dl_malloc_function)
 855                 return (*_dl_malloc_function) (size);
 856
 857         if (_dl_malloc_addr - _dl_mmap_zero + (unsigned)size > _dl_pagesize) {
 858                 _dl_debug_early("mmapping more memory\n");
 859                 _dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, size,
 860                                 PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 861                 if (_dl_mmap_check_error(_dl_mmap_zero)) {
 862                         _dl_dprintf(_dl_debug_file, "%s: mmap of a spare page failed!\n", _dl_progname);
 863                         _dl_exit(20);
 864                 }
 865         }
 866         retval = _dl_malloc_addr;
 867         _dl_malloc_addr += size;
 868
 869         /*
 870          * Align memory to 4 byte boundary.  Some platforms require this,
 871          * others simply get better performance.
 872          */
 873         _dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + 3) & ~(3));
 874         return retval;
 875 }
 876
 877 #include "dl-hash.c"
 878 #include "dl-elf.c"