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