ldso.c 26 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880
  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. #include "ldso.h"
  33. #include "unsecvars.h"
  34. /* Pull in common debug code */
  35. #include "dl-debug.c"
  36. #define ALLOW_ZERO_PLTGOT
  37. /* Pull in the value of _dl_progname */
  38. #include LDSO_ELFINTERP
  39. /* Global variables used within the shared library loader */
  40. char *_dl_library_path = 0; /* Where we look for libraries */
  41. char *_dl_preload = 0; /* Things to be loaded before the libs */
  42. char *_dl_ldsopath = 0; /* Location of the shared lib loader */
  43. int _dl_secure = 1; /* Are we dealing with setuid stuff? */
  44. int _dl_errno = 0; /* We can't use the real errno in ldso */
  45. size_t _dl_pagesize = 0; /* Store the page size for use later */
  46. struct r_debug *_dl_debug_addr = NULL; /* Used to communicate with the gdb debugger */
  47. void *(*_dl_malloc_function) (size_t size) = NULL;
  48. #ifdef __SUPPORT_LD_DEBUG__
  49. char *_dl_debug = 0;
  50. char *_dl_debug_symbols = 0;
  51. char *_dl_debug_move = 0;
  52. char *_dl_debug_reloc = 0;
  53. char *_dl_debug_detail = 0;
  54. char *_dl_debug_nofixups = 0;
  55. char *_dl_debug_bindings = 0;
  56. int _dl_debug_file = 2;
  57. #endif
  58. /* Needed for standalone execution. */
  59. unsigned long attribute_hidden _dl_skip_args = 0;
  60. const char *_dl_progname = UCLIBC_LDSO; /* The name of the executable being run */
  61. #include "dl-startup.c"
  62. /* Forward function declarations */
  63. static int _dl_suid_ok(void);
  64. /*
  65. * This stub function is used by some debuggers. The idea is that they
  66. * can set an internal breakpoint on it, so that we are notified when the
  67. * address mapping is changed in some way.
  68. */
  69. void _dl_debug_state(void);
  70. void _dl_debug_state()
  71. {
  72. }
  73. static unsigned char *_dl_malloc_addr = 0; /* Lets _dl_malloc use the already allocated memory page */
  74. static unsigned char *_dl_mmap_zero = 0; /* Also used by _dl_malloc */
  75. static struct elf_resolve **init_fini_list;
  76. static unsigned int nlist; /* # items in init_fini_list */
  77. extern void _start(void);
  78. #ifdef __UCLIBC_HAS_SSP__
  79. #include <dl-osinfo.h>
  80. uintptr_t stack_chk_guard;
  81. #ifndef THREAD_SET_STACK_GUARD
  82. /* Only exported for architectures that don't store the stack guard canary
  83. * in local thread area. */
  84. uintptr_t __stack_chk_guard attribute_relro;
  85. strong_alias(__stack_chk_guard,__guard)
  86. #endif
  87. #endif
  88. static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void)
  89. {
  90. int i;
  91. struct elf_resolve * tpnt;
  92. for (i = 0; i < nlist; ++i) {
  93. tpnt = init_fini_list[i];
  94. if (tpnt->init_flag & FINI_FUNCS_CALLED)
  95. continue;
  96. tpnt->init_flag |= FINI_FUNCS_CALLED;
  97. if (tpnt->dynamic_info[DT_FINI]) {
  98. void (*dl_elf_func) (void);
  99. dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
  100. _dl_if_debug_dprint("\ncalling FINI: %s\n\n", tpnt->libname);
  101. (*dl_elf_func) ();
  102. }
  103. }
  104. }
  105. void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
  106. ElfW(auxv_t) auxvt[AT_EGID + 1], char **envp,
  107. char **argv)
  108. {
  109. ElfW(Phdr) *ppnt;
  110. ElfW(Dyn) *dpnt;
  111. char *lpntstr;
  112. unsigned int i;
  113. int unlazy = 0, trace_loaded_objects = 0;
  114. struct dyn_elf *rpnt;
  115. struct elf_resolve *tcurr;
  116. struct elf_resolve *tpnt1;
  117. struct elf_resolve app_tpnt_tmp;
  118. struct elf_resolve *app_tpnt = &app_tpnt_tmp;
  119. struct r_debug *debug_addr;
  120. unsigned long *lpnt;
  121. unsigned long *_dl_envp; /* The environment address */
  122. ElfW(Addr) relro_addr = 0;
  123. size_t relro_size = 0;
  124. /* Wahoo!!! We managed to make a function call! Get malloc
  125. * setup so we can use _dl_dprintf() to print debug noise
  126. * instead of the SEND_STDERR macros used in dl-startup.c */
  127. _dl_memset(app_tpnt, 0x00, sizeof(*app_tpnt));
  128. /* Store the page size for later use */
  129. _dl_pagesize = (auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE;
  130. /* Make it so _dl_malloc can use the page of memory we have already
  131. * allocated. We shouldn't need to grab any more memory. This must
  132. * be first since things like _dl_dprintf() use _dl_malloc()...
  133. */
  134. _dl_malloc_addr = (unsigned char *)_dl_pagesize;
  135. _dl_mmap_zero = 0;
  136. /* Wahoo!!! */
  137. _dl_debug_early("Cool, ldso survived making function calls\n");
  138. /* Now we have done the mandatory linking of some things. We are now
  139. * free to start using global variables, since these things have all
  140. * been fixed up by now. Still no function calls outside of this
  141. * library, since the dynamic resolver is not yet ready.
  142. */
  143. if (argv[0]) {
  144. _dl_progname = argv[0];
  145. }
  146. if (_start == (void *) auxvt[AT_ENTRY].a_un.a_val) {
  147. _dl_dprintf(_dl_debug_file, "Standalone execution is not supported yet\n");
  148. _dl_exit(1);
  149. }
  150. /* Start to build the tables of the modules that are required for
  151. * this beast to run. We start with the basic executable, and then
  152. * go from there. Eventually we will run across ourself, and we
  153. * will need to properly deal with that as well.
  154. */
  155. rpnt = NULL;
  156. if (_dl_getenv("LD_BIND_NOW", envp))
  157. unlazy = RTLD_NOW;
  158. /* Now we need to figure out what kind of options are selected.
  159. * Note that for SUID programs we ignore the settings in
  160. * LD_LIBRARY_PATH.
  161. */
  162. if ((auxvt[AT_UID].a_un.a_val == (size_t)-1 && _dl_suid_ok()) ||
  163. (auxvt[AT_UID].a_un.a_val != (size_t)-1 &&
  164. auxvt[AT_UID].a_un.a_val == auxvt[AT_EUID].a_un.a_val &&
  165. auxvt[AT_GID].a_un.a_val == auxvt[AT_EGID].a_un.a_val)) {
  166. _dl_secure = 0;
  167. _dl_preload = _dl_getenv("LD_PRELOAD", envp);
  168. _dl_library_path = _dl_getenv("LD_LIBRARY_PATH", envp);
  169. } else {
  170. static const char unsecure_envvars[] =
  171. #ifdef EXTRA_UNSECURE_ENVVARS
  172. EXTRA_UNSECURE_ENVVARS
  173. #endif
  174. UNSECURE_ENVVARS;
  175. const char *nextp;
  176. _dl_secure = 1;
  177. nextp = unsecure_envvars;
  178. do {
  179. _dl_unsetenv (nextp, envp);
  180. /* We could use rawmemchr but this need not be fast. */
  181. nextp = (char *) _dl_strchr(nextp, '\0') + 1;
  182. } while (*nextp != '\0');
  183. _dl_preload = NULL;
  184. _dl_library_path = NULL;
  185. /* SUID binaries can be exploited if they do LAZY relocation. */
  186. unlazy = RTLD_NOW;
  187. }
  188. /* sjhill: your TLS init should go before this */
  189. #ifdef __UCLIBC_HAS_SSP__
  190. /* Set up the stack checker's canary. */
  191. stack_chk_guard = _dl_setup_stack_chk_guard ();
  192. # ifdef THREAD_SET_STACK_GUARD
  193. THREAD_SET_STACK_GUARD (stack_chk_guard);
  194. # else
  195. __stack_chk_guard = stack_chk_guard;
  196. # endif
  197. #endif
  198. /* At this point we are now free to examine the user application,
  199. * and figure out which libraries are supposed to be called. Until
  200. * we have this list, we will not be completely ready for dynamic
  201. * linking.
  202. */
  203. /* Find the runtime load address of the main executable. This may be
  204. * different from what the ELF header says for ET_DYN/PIE executables.
  205. */
  206. {
  207. unsigned int i;
  208. ElfW(Phdr) *ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
  209. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++)
  210. if (ppnt->p_type == PT_PHDR) {
  211. app_tpnt->loadaddr = (ElfW(Addr)) (auxvt[AT_PHDR].a_un.a_val - ppnt->p_vaddr);
  212. break;
  213. }
  214. if (app_tpnt->loadaddr)
  215. _dl_debug_early("Position Independent Executable: "
  216. "app_tpnt->loadaddr=%x\n", app_tpnt->loadaddr);
  217. }
  218. /*
  219. * This is used by gdb to locate the chain of shared libraries that are
  220. * currently loaded.
  221. */
  222. debug_addr = _dl_malloc(sizeof(struct r_debug));
  223. _dl_memset(debug_addr, 0, sizeof(struct r_debug));
  224. ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
  225. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
  226. if (ppnt->p_type == PT_GNU_RELRO) {
  227. relro_addr = ppnt->p_vaddr;
  228. relro_size = ppnt->p_memsz;
  229. }
  230. if (ppnt->p_type == PT_DYNAMIC) {
  231. dpnt = (ElfW(Dyn) *) (ppnt->p_vaddr + app_tpnt->loadaddr);
  232. _dl_parse_dynamic_info(dpnt, app_tpnt->dynamic_info, debug_addr, app_tpnt->loadaddr);
  233. #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
  234. /* Ugly, ugly. We need to call mprotect to change the
  235. * protection of the text pages so that we can do the
  236. * dynamic linking. We can set the protection back
  237. * again once we are done.
  238. */
  239. _dl_debug_early("calling mprotect on the application program\n");
  240. /* Now cover the application program. */
  241. if (app_tpnt->dynamic_info[DT_TEXTREL]) {
  242. ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
  243. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
  244. if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W))
  245. _dl_mprotect((void *) ((ppnt->p_vaddr + app_tpnt->loadaddr) & PAGE_ALIGN),
  246. ((ppnt->p_vaddr + app_tpnt->loadaddr) & ADDR_ALIGN) +
  247. (unsigned long) ppnt->p_filesz,
  248. PROT_READ | PROT_WRITE | PROT_EXEC);
  249. }
  250. }
  251. #endif
  252. #ifndef ALLOW_ZERO_PLTGOT
  253. /* make sure it's really there. */
  254. if (app_tpnt->dynamic_info[DT_PLTGOT] == 0)
  255. continue;
  256. #endif
  257. /* OK, we have what we need - slip this one into the list. */
  258. app_tpnt = _dl_add_elf_hash_table(_dl_progname, (char *)app_tpnt->loadaddr,
  259. app_tpnt->dynamic_info, ppnt->p_vaddr + app_tpnt->loadaddr, ppnt->p_filesz);
  260. _dl_loaded_modules->libtype = elf_executable;
  261. _dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
  262. _dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
  263. _dl_symbol_tables = rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  264. _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
  265. rpnt->dyn = _dl_loaded_modules;
  266. app_tpnt->rtld_flags = unlazy | RTLD_GLOBAL;
  267. app_tpnt->usage_count++;
  268. app_tpnt->symbol_scope = _dl_symbol_tables;
  269. lpnt = (unsigned long *) (app_tpnt->dynamic_info[DT_PLTGOT]);
  270. #ifdef ALLOW_ZERO_PLTGOT
  271. if (lpnt)
  272. #endif
  273. INIT_GOT(lpnt, _dl_loaded_modules);
  274. }
  275. /* OK, fill this in - we did not have this before */
  276. if (ppnt->p_type == PT_INTERP) {
  277. char *ptmp;
  278. tpnt->libname = (char *) ppnt->p_vaddr + app_tpnt->loadaddr;
  279. /* Store the path where the shared lib loader was found
  280. * for later use
  281. */
  282. _dl_ldsopath = _dl_strdup(tpnt->libname);
  283. ptmp = _dl_strrchr(_dl_ldsopath, '/');
  284. if (ptmp != _dl_ldsopath)
  285. *ptmp = '\0';
  286. _dl_debug_early("Lib Loader: (%x) %s\n", tpnt->loadaddr, tpnt->libname);
  287. }
  288. }
  289. app_tpnt->relro_addr = relro_addr;
  290. app_tpnt->relro_size = relro_size;
  291. #ifdef __SUPPORT_LD_DEBUG__
  292. _dl_debug = _dl_getenv("LD_DEBUG", envp);
  293. if (_dl_debug) {
  294. if (_dl_strstr(_dl_debug, "all")) {
  295. _dl_debug_detail = _dl_debug_move = _dl_debug_symbols
  296. = _dl_debug_reloc = _dl_debug_bindings = _dl_debug_nofixups = (void*)1;
  297. } else {
  298. _dl_debug_detail = _dl_strstr(_dl_debug, "detail");
  299. _dl_debug_move = _dl_strstr(_dl_debug, "move");
  300. _dl_debug_symbols = _dl_strstr(_dl_debug, "sym");
  301. _dl_debug_reloc = _dl_strstr(_dl_debug, "reloc");
  302. _dl_debug_nofixups = _dl_strstr(_dl_debug, "nofix");
  303. _dl_debug_bindings = _dl_strstr(_dl_debug, "bind");
  304. }
  305. }
  306. {
  307. const char *dl_debug_output;
  308. dl_debug_output = _dl_getenv("LD_DEBUG_OUTPUT", envp);
  309. if (dl_debug_output) {
  310. char tmp[22], *tmp1, *filename;
  311. int len1, len2;
  312. _dl_memset(tmp, 0, sizeof(tmp));
  313. tmp1 = _dl_simple_ltoa( tmp, (unsigned long)_dl_getpid());
  314. len1 = _dl_strlen(dl_debug_output);
  315. len2 = _dl_strlen(tmp1);
  316. filename = _dl_malloc(len1+len2+2);
  317. if (filename) {
  318. _dl_strcpy (filename, dl_debug_output);
  319. filename[len1] = '.';
  320. _dl_strcpy (&filename[len1+1], tmp1);
  321. _dl_debug_file= _dl_open(filename, O_WRONLY|O_CREAT, 0644);
  322. if (_dl_debug_file < 0) {
  323. _dl_debug_file = 2;
  324. _dl_dprintf(_dl_debug_file, "can't open file: '%s'\n",filename);
  325. }
  326. }
  327. }
  328. }
  329. #endif
  330. if (_dl_getenv("LD_TRACE_LOADED_OBJECTS", envp) != NULL) {
  331. trace_loaded_objects++;
  332. }
  333. #ifndef __LDSO_LDD_SUPPORT__
  334. if (trace_loaded_objects) {
  335. _dl_dprintf(_dl_debug_file, "Use the ldd provided by uClibc\n");
  336. _dl_exit(1);
  337. }
  338. #endif
  339. /*
  340. * OK, fix one more thing - set up debug_addr so it will point
  341. * to our chain. Later we may need to fill in more fields, but this
  342. * should be enough for now.
  343. */
  344. debug_addr->r_map = (struct link_map *) _dl_loaded_modules;
  345. debug_addr->r_version = 1;
  346. debug_addr->r_ldbase = load_addr;
  347. debug_addr->r_brk = (unsigned long) &_dl_debug_state;
  348. _dl_debug_addr = debug_addr;
  349. /* Notify the debugger we are in a consistant state */
  350. _dl_debug_addr->r_state = RT_CONSISTENT;
  351. _dl_debug_state();
  352. /* OK, we now have the application in the list, and we have some
  353. * basic stuff in place. Now search through the list for other shared
  354. * libraries that should be loaded, and insert them on the list in the
  355. * correct order.
  356. */
  357. _dl_map_cache();
  358. if (_dl_preload) {
  359. char c, *str, *str2;
  360. str = _dl_preload;
  361. while (*str == ':' || *str == ' ' || *str == '\t')
  362. str++;
  363. while (*str) {
  364. str2 = str;
  365. while (*str2 && *str2 != ':' && *str2 != ' ' && *str2 != '\t')
  366. str2++;
  367. c = *str2;
  368. *str2 = '\0';
  369. if (!_dl_secure || _dl_strchr(str, '/') == NULL) {
  370. _dl_if_debug_dprint("\tfile='%s'; needed by '%s'\n", str, _dl_progname);
  371. tpnt1 = _dl_load_shared_library(_dl_secure, &rpnt, NULL, str, trace_loaded_objects);
  372. if (!tpnt1) {
  373. #ifdef __LDSO_LDD_SUPPORT__
  374. if (trace_loaded_objects)
  375. _dl_dprintf(1, "\t%s => not found\n", str);
  376. else
  377. #endif
  378. {
  379. _dl_dprintf(_dl_debug_file, "%s: can't load " "library '%s'\n", _dl_progname, str);
  380. _dl_exit(15);
  381. }
  382. } else {
  383. tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
  384. _dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  385. #ifdef __LDSO_LDD_SUPPORT__
  386. if (trace_loaded_objects &&
  387. tpnt1->usage_count == 1) {
  388. /* This is a real hack to make
  389. * ldd not print the library
  390. * itself when run on a
  391. * library.
  392. */
  393. if (_dl_strcmp(_dl_progname, str) != 0)
  394. _dl_dprintf(1, "\t%s => %s (%x)\n", str, tpnt1->libname,
  395. tpnt1->loadaddr);
  396. }
  397. #endif
  398. }
  399. }
  400. *str2 = c;
  401. str = str2;
  402. while (*str == ':' || *str == ' ' || *str == '\t')
  403. str++;
  404. }
  405. }
  406. #ifdef __LDSO_PRELOAD_FILE_SUPPORT__
  407. do {
  408. struct stat st;
  409. char *preload;
  410. int fd;
  411. char c, *cp, *cp2;
  412. if (_dl_stat(LDSO_PRELOAD, &st) || st.st_size == 0) {
  413. break;
  414. }
  415. if ((fd = _dl_open(LDSO_PRELOAD, O_RDONLY, 0)) < 0) {
  416. _dl_dprintf(_dl_debug_file, "%s: can't open file '%s'\n",
  417. _dl_progname, LDSO_PRELOAD);
  418. break;
  419. }
  420. preload = (caddr_t) _dl_mmap(0, st.st_size + 1,
  421. PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
  422. _dl_close(fd);
  423. if (preload == (caddr_t) -1) {
  424. _dl_dprintf(_dl_debug_file, "%s: can't map file '%s'\n",
  425. _dl_progname, LDSO_PRELOAD);
  426. break;
  427. }
  428. /* convert all separators and comments to spaces */
  429. for (cp = preload; *cp; /*nada */ ) {
  430. if (*cp == ':' || *cp == '\t' || *cp == '\n') {
  431. *cp++ = ' ';
  432. } else if (*cp == '#') {
  433. do {
  434. *cp++ = ' ';
  435. } while (*cp != '\n' && *cp != '\0');
  436. } else {
  437. cp++;
  438. }
  439. }
  440. /* find start of first library */
  441. for (cp = preload; *cp && *cp == ' '; cp++)
  442. /*nada */ ;
  443. while (*cp) {
  444. /* find end of library */
  445. for (cp2 = cp; *cp && *cp != ' '; cp++)
  446. /*nada */ ;
  447. c = *cp;
  448. *cp = '\0';
  449. _dl_if_debug_dprint("\tfile='%s'; needed by '%s'\n", cp2, _dl_progname);
  450. tpnt1 = _dl_load_shared_library(0, &rpnt, NULL, cp2, trace_loaded_objects);
  451. if (!tpnt1) {
  452. #ifdef __LDSO_LDD_SUPPORT__
  453. if (trace_loaded_objects)
  454. _dl_dprintf(1, "\t%s => not found\n", cp2);
  455. else
  456. #endif
  457. {
  458. _dl_dprintf(_dl_debug_file, "%s: can't load library '%s'\n", _dl_progname, cp2);
  459. _dl_exit(15);
  460. }
  461. } else {
  462. tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
  463. _dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  464. #ifdef __LDSO_LDD_SUPPORT__
  465. if (trace_loaded_objects &&
  466. tpnt1->usage_count == 1) {
  467. _dl_dprintf(1, "\t%s => %s (%x)\n",
  468. cp2, tpnt1->libname,
  469. (unsigned)tpnt1->loadaddr);
  470. }
  471. #endif
  472. }
  473. /* find start of next library */
  474. *cp = c;
  475. for ( /*nada */ ; *cp && *cp == ' '; cp++)
  476. /*nada */ ;
  477. }
  478. _dl_munmap(preload, st.st_size + 1);
  479. } while (0);
  480. #endif /* __LDSO_PRELOAD_FILE_SUPPORT__ */
  481. nlist = 0;
  482. for (tcurr = _dl_loaded_modules; tcurr; tcurr = tcurr->next) {
  483. ElfW(Dyn) *dpnt;
  484. nlist++;
  485. for (dpnt = (ElfW(Dyn) *) tcurr->dynamic_addr; dpnt->d_tag; dpnt++) {
  486. if (dpnt->d_tag == DT_NEEDED) {
  487. char *name;
  488. struct init_fini_list *tmp;
  489. lpntstr = (char*) (tcurr->dynamic_info[DT_STRTAB] + dpnt->d_un.d_val);
  490. name = _dl_get_last_path_component(lpntstr);
  491. if (_dl_strcmp(name, UCLIBC_LDSO) == 0)
  492. continue;
  493. _dl_if_debug_dprint("\tfile='%s'; needed by '%s'\n", lpntstr, _dl_progname);
  494. if (!(tpnt1 = _dl_load_shared_library(0, &rpnt, tcurr, lpntstr, trace_loaded_objects))) {
  495. #ifdef __LDSO_LDD_SUPPORT__
  496. if (trace_loaded_objects) {
  497. _dl_dprintf(1, "\t%s => not found\n", lpntstr);
  498. continue;
  499. } else
  500. #endif
  501. {
  502. _dl_dprintf(_dl_debug_file, "%s: can't load library '%s'\n", _dl_progname, lpntstr);
  503. _dl_exit(16);
  504. }
  505. }
  506. tmp = alloca(sizeof(struct init_fini_list)); /* Allocates on stack, no need to free this memory */
  507. tmp->tpnt = tpnt1;
  508. tmp->next = tcurr->init_fini;
  509. tcurr->init_fini = tmp;
  510. tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
  511. _dl_debug_early("Loading: (%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  512. #ifdef __LDSO_LDD_SUPPORT__
  513. if (trace_loaded_objects &&
  514. tpnt1->usage_count == 1) {
  515. _dl_dprintf(1, "\t%s => %s (%x)\n",
  516. lpntstr, tpnt1->libname,
  517. (unsigned)tpnt1->loadaddr);
  518. }
  519. #endif
  520. }
  521. }
  522. }
  523. _dl_unmap_cache();
  524. --nlist; /* Exclude the application. */
  525. init_fini_list = _dl_malloc(nlist * sizeof(struct elf_resolve *));
  526. i = 0;
  527. for (tcurr = _dl_loaded_modules->next; tcurr; tcurr = tcurr->next) {
  528. init_fini_list[i++] = tcurr;
  529. }
  530. /* Sort the INIT/FINI list in dependency order. */
  531. for (tcurr = _dl_loaded_modules->next; tcurr; tcurr = tcurr->next) {
  532. int j, k;
  533. for (j = 0; init_fini_list[j] != tcurr; ++j)
  534. /* Empty */;
  535. for (k = j + 1; k < nlist; ++k) {
  536. struct init_fini_list *runp = init_fini_list[k]->init_fini;
  537. for (; runp; runp = runp->next) {
  538. if (runp->tpnt == tcurr) {
  539. struct elf_resolve *here = init_fini_list[k];
  540. _dl_if_debug_dprint("Move %s from pos %d to %d in INIT/FINI list\n", here->libname, k, j);
  541. for (i = (k - j); i; --i)
  542. init_fini_list[i+j] = init_fini_list[i+j-1];
  543. init_fini_list[j] = here;
  544. ++j;
  545. break;
  546. }
  547. }
  548. }
  549. }
  550. #ifdef __SUPPORT_LD_DEBUG__
  551. if(_dl_debug) {
  552. _dl_dprintf(_dl_debug_file, "\nINIT/FINI order and dependencies:\n");
  553. for (i = 0; i < nlist; i++) {
  554. struct init_fini_list *tmp;
  555. _dl_dprintf(_dl_debug_file, "lib: %s has deps:\n",
  556. init_fini_list[i]->libname);
  557. tmp = init_fini_list[i]->init_fini;
  558. for (; tmp; tmp = tmp->next)
  559. _dl_dprintf(_dl_debug_file, " %s ", tmp->tpnt->libname);
  560. _dl_dprintf(_dl_debug_file, "\n");
  561. }
  562. }
  563. #endif
  564. /*
  565. * If the program interpreter is not in the module chain, add it.
  566. * This will be required for dlopen to be able to access the internal
  567. * functions in the dynamic linker and to relocate the interpreter
  568. * again once all libs are loaded.
  569. */
  570. if (tpnt) {
  571. ElfW(Ehdr) *epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_val;
  572. ElfW(Phdr) *myppnt = (ElfW(Phdr) *) (load_addr + epnt->e_phoff);
  573. int j;
  574. tpnt = _dl_add_elf_hash_table(tpnt->libname, (char *)load_addr,
  575. tpnt->dynamic_info,
  576. (unsigned long)tpnt->dynamic_addr,
  577. 0);
  578. tpnt->n_phent = epnt->e_phnum;
  579. tpnt->ppnt = myppnt;
  580. for (j = 0; j < epnt->e_phnum; j++, myppnt++) {
  581. if (myppnt->p_type == PT_GNU_RELRO) {
  582. tpnt->relro_addr = myppnt->p_vaddr;
  583. tpnt->relro_size = myppnt->p_memsz;
  584. break;
  585. }
  586. }
  587. tpnt->libtype = program_interpreter;
  588. tpnt->usage_count++;
  589. tpnt->symbol_scope = _dl_symbol_tables;
  590. if (rpnt) {
  591. rpnt->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  592. _dl_memset(rpnt->next, 0, sizeof(struct dyn_elf));
  593. rpnt->next->prev = rpnt;
  594. rpnt = rpnt->next;
  595. } else {
  596. rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  597. _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
  598. }
  599. rpnt->dyn = tpnt;
  600. tpnt->rtld_flags = RTLD_NOW | RTLD_GLOBAL; /* Must not be LAZY */
  601. #ifdef RERELOCATE_LDSO
  602. /* Only rerelocate functions for now. */
  603. tpnt->init_flag = RELOCS_DONE;
  604. lpnt = (unsigned long *) (tpnt->dynamic_info[DT_PLTGOT]);
  605. # ifdef ALLOW_ZERO_PLTGOT
  606. if (tpnt->dynamic_info[DT_PLTGOT])
  607. # endif
  608. INIT_GOT(lpnt, tpnt);
  609. #else
  610. tpnt->init_flag = RELOCS_DONE | JMP_RELOCS_DONE;
  611. #endif
  612. tpnt = NULL;
  613. }
  614. #ifdef __LDSO_LDD_SUPPORT__
  615. /* End of the line for ldd.... */
  616. if (trace_loaded_objects) {
  617. _dl_dprintf(1, "\t%s => %s (%x)\n",
  618. rpnt->dyn->libname + _dl_strlen(_dl_ldsopath) + 1,
  619. rpnt->dyn->libname, rpnt->dyn->loadaddr);
  620. _dl_exit(0);
  621. }
  622. #endif
  623. _dl_debug_early("Beginning relocation fixups\n");
  624. #ifdef __mips__
  625. /*
  626. * Relocation of the GOT entries for MIPS have to be done
  627. * after all the libraries have been loaded.
  628. */
  629. _dl_perform_mips_global_got_relocations(_dl_loaded_modules, !unlazy);
  630. #endif
  631. /*
  632. * OK, now all of the kids are tucked into bed in their proper
  633. * addresses. Now we go through and look for REL and RELA records that
  634. * indicate fixups to the GOT tables. We need to do this in reverse
  635. * order so that COPY directives work correctly.
  636. */
  637. if (_dl_symbol_tables)
  638. if (_dl_fixup(_dl_symbol_tables, unlazy))
  639. _dl_exit(-1);
  640. for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
  641. if (tpnt->relro_size)
  642. _dl_protect_relro (tpnt);
  643. }
  644. /* OK, at this point things are pretty much ready to run. Now we need
  645. * to touch up a few items that are required, and then we can let the
  646. * user application have at it. Note that the dynamic linker itself
  647. * is not guaranteed to be fully dynamicly linked if we are using
  648. * ld.so.1, so we have to look up each symbol individually.
  649. */
  650. _dl_envp = (unsigned long *) (intptr_t) _dl_find_hash("__environ", _dl_symbol_tables, NULL, 0);
  651. if (_dl_envp)
  652. *_dl_envp = (unsigned long) envp;
  653. #ifndef __FORCE_SHAREABLE_TEXT_SEGMENTS__
  654. {
  655. unsigned int j;
  656. ElfW(Phdr) *myppnt;
  657. /* We had to set the protections of all pages to R/W for
  658. * dynamic linking. Set text pages back to R/O.
  659. */
  660. for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
  661. for (myppnt = tpnt->ppnt, j = 0; j < tpnt->n_phent; j++, myppnt++) {
  662. if (myppnt->p_type == PT_LOAD && !(myppnt->p_flags & PF_W) && tpnt->dynamic_info[DT_TEXTREL]) {
  663. _dl_mprotect((void *) (tpnt->loadaddr + (myppnt->p_vaddr & PAGE_ALIGN)),
  664. (myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz, LXFLAGS(myppnt->p_flags));
  665. }
  666. }
  667. }
  668. }
  669. #endif
  670. /* Notify the debugger we have added some objects. */
  671. _dl_debug_addr->r_state = RT_ADD;
  672. _dl_debug_state();
  673. for (i = nlist; i; --i) {
  674. tpnt = init_fini_list[i-1];
  675. tpnt->init_fini = NULL; /* Clear, since alloca was used */
  676. if (tpnt->init_flag & INIT_FUNCS_CALLED)
  677. continue;
  678. tpnt->init_flag |= INIT_FUNCS_CALLED;
  679. if (tpnt->dynamic_info[DT_INIT]) {
  680. void (*dl_elf_func) (void);
  681. dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
  682. _dl_if_debug_dprint("calling INIT: %s\n\n", tpnt->libname);
  683. (*dl_elf_func) ();
  684. }
  685. }
  686. /* Find the real malloc function and make ldso functions use that from now on */
  687. _dl_malloc_function = (void* (*)(size_t)) (intptr_t) _dl_find_hash("malloc",
  688. _dl_symbol_tables, NULL, ELF_RTYPE_CLASS_PLT);
  689. /* Notify the debugger that all objects are now mapped in. */
  690. _dl_debug_addr->r_state = RT_CONSISTENT;
  691. _dl_debug_state();
  692. }
  693. char *_dl_getenv(const char *symbol, char **envp)
  694. {
  695. char *pnt;
  696. const char *pnt1;
  697. while ((pnt = *envp++)) {
  698. pnt1 = symbol;
  699. while (*pnt && *pnt == *pnt1)
  700. pnt1++, pnt++;
  701. if (!*pnt || *pnt != '=' || *pnt1)
  702. continue;
  703. return pnt + 1;
  704. }
  705. return 0;
  706. }
  707. void _dl_unsetenv(const char *symbol, char **envp)
  708. {
  709. char *pnt;
  710. const char *pnt1;
  711. char **newenvp = envp;
  712. for (pnt = *envp; pnt; pnt = *++envp) {
  713. pnt1 = symbol;
  714. while (*pnt && *pnt == *pnt1)
  715. pnt1++, pnt++;
  716. if (!*pnt || *pnt != '=' || *pnt1)
  717. *newenvp++ = *envp;
  718. }
  719. *newenvp++ = *envp;
  720. return;
  721. }
  722. static int _dl_suid_ok(void)
  723. {
  724. __kernel_uid_t uid, euid;
  725. __kernel_gid_t gid, egid;
  726. uid = _dl_getuid();
  727. euid = _dl_geteuid();
  728. gid = _dl_getgid();
  729. egid = _dl_getegid();
  730. if(uid == euid && gid == egid) {
  731. return 1;
  732. }
  733. return 0;
  734. }
  735. void *_dl_malloc(int size)
  736. {
  737. void *retval;
  738. #if 0
  739. _dl_debug_early("request for %d bytes\n", size);
  740. #endif
  741. if (_dl_malloc_function)
  742. return (*_dl_malloc_function) (size);
  743. if (_dl_malloc_addr - _dl_mmap_zero + (unsigned)size > _dl_pagesize) {
  744. _dl_debug_early("mmapping more memory\n");
  745. _dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, size,
  746. PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  747. if (_dl_mmap_check_error(_dl_mmap_zero)) {
  748. _dl_dprintf(_dl_debug_file, "%s: mmap of a spare page failed!\n", _dl_progname);
  749. _dl_exit(20);
  750. }
  751. }
  752. retval = _dl_malloc_addr;
  753. _dl_malloc_addr += size;
  754. /*
  755. * Align memory to 4 byte boundary. Some platforms require this,
  756. * others simply get better performance.
  757. */
  758. _dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + 3) & ~(3));
  759. return retval;
  760. }
  761. #include "dl-hash.c"
  762. #include "dl-elf.c"