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