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