ldso.c 26 KB

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  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) 2000-2004 by Erik Andersen <andersen@codpoet.org>
  7. * Copyright (c) 1994-2000 Eric Youngdale, Peter MacDonald,
  8. * David Engel, Hongjiu Lu and Mitch D'Souza
  9. *
  10. * Redistribution and use in source and binary forms, with or without
  11. * modification, are permitted provided that the following conditions
  12. * are met:
  13. * 1. Redistributions of source code must retain the above copyright
  14. * notice, this list of conditions and the following disclaimer.
  15. * 2. The name of the above contributors may not be
  16. * used to endorse or promote products derived from this software
  17. * without specific prior written permission.
  18. *
  19. * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
  20. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22. * ARE DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE
  23. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29. * SUCH DAMAGE.
  30. */
  31. #include "ldso.h"
  32. #define ALLOW_ZERO_PLTGOT
  33. /* Pull in the value of _dl_progname */
  34. #include "dl-progname.h"
  35. /* Global variables used within the shared library loader */
  36. char *_dl_library_path = 0; /* Where we look for libraries */
  37. char *_dl_preload = 0; /* Things to be loaded before the libs */
  38. char *_dl_ldsopath = 0; /* Location of the shared lib loader */
  39. int _dl_secure = 1; /* Are we dealing with setuid stuff? */
  40. int _dl_errno = 0; /* We can't use the real errno in ldso */
  41. size_t _dl_pagesize = 0; /* Store the page size for use later */
  42. struct r_debug *_dl_debug_addr = NULL; /* Used to communicate with the gdb debugger */
  43. void *(*_dl_malloc_function) (size_t size) = NULL;
  44. #ifdef __SUPPORT_LD_DEBUG__
  45. char *_dl_debug = 0;
  46. char *_dl_debug_symbols = 0;
  47. char *_dl_debug_move = 0;
  48. char *_dl_debug_reloc = 0;
  49. char *_dl_debug_detail = 0;
  50. char *_dl_debug_nofixups = 0;
  51. char *_dl_debug_bindings = 0;
  52. int _dl_debug_file = 2;
  53. #endif
  54. /* Forward function declarations */
  55. static int _dl_suid_ok(void);
  56. /*
  57. * This stub function is used by some debuggers. The idea is that they
  58. * can set an internal breakpoint on it, so that we are notified when the
  59. * address mapping is changed in some way.
  60. */
  61. void _dl_debug_state(void)
  62. {
  63. }
  64. static unsigned char *_dl_malloc_addr = 0; /* Lets _dl_malloc use the already allocated memory page */
  65. static unsigned char *_dl_mmap_zero = 0; /* Also used by _dl_malloc */
  66. #if defined (__SUPPORT_LD_DEBUG__)
  67. static void debug_fini (int status, void *arg)
  68. {
  69. (void)status;
  70. _dl_dprintf(_dl_debug_file,"\ncalling fini: %s\n\n", (const char*)arg);
  71. }
  72. #endif
  73. void _dl_get_ready_to_run(struct elf_resolve *tpnt, unsigned long load_addr,
  74. Elf32_auxv_t auxvt[AT_EGID + 1], char **envp, char **argv)
  75. {
  76. ElfW(Phdr) *ppnt;
  77. Elf32_Dyn *dpnt;
  78. char *lpntstr;
  79. int i, goof = 0, unlazy = 0, trace_loaded_objects = 0;
  80. struct dyn_elf *rpnt;
  81. struct elf_resolve *tcurr;
  82. struct elf_resolve *tpnt1;
  83. struct elf_resolve app_tpnt_tmp;
  84. struct elf_resolve *app_tpnt = &app_tpnt_tmp;
  85. struct r_debug *debug_addr;
  86. unsigned long brk_addr, *lpnt;
  87. int (*_dl_atexit) (void *);
  88. #if defined (__SUPPORT_LD_DEBUG__)
  89. int (*_dl_on_exit) (void (*FUNCTION)(int STATUS, void *ARG),void*);
  90. #endif
  91. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  92. /* Wahoo!!! */
  93. SEND_STDERR("Cool, we managed to make a function call.\n");
  94. #endif
  95. /* Store the page size for later use */
  96. _dl_pagesize = (auxvt[AT_PAGESZ].a_un.a_val)? (size_t) auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE;
  97. /* Make it so _dl_malloc can use the page of memory we have already
  98. * allocated. We shouldn't need to grab any more memory. This must
  99. * be first since things like _dl_dprintf() use _dl_malloc().... */
  100. _dl_malloc_addr = (unsigned char *)_dl_pagesize;
  101. _dl_mmap_zero = 0;
  102. /* Now we have done the mandatory linking of some things. We are now
  103. * free to start using global variables, since these things have all been
  104. * fixed up by now. Still no function calls outside of this library ,
  105. * since the dynamic resolver is not yet ready. */
  106. if (argv[0]) {
  107. _dl_progname = argv[0];
  108. }
  109. /* Start to build the tables of the modules that are required for
  110. * this beast to run. We start with the basic executable, and then
  111. * go from there. Eventually we will run across ourself, and we
  112. * will need to properly deal with that as well. */
  113. {
  114. ElfW(Ehdr) *epnt;
  115. ElfW(Phdr) *myppnt;
  116. int j;
  117. epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_ptr;
  118. tpnt->n_phent = epnt->e_phnum;
  119. tpnt->ppnt = myppnt = (ElfW(Phdr) *) (load_addr + epnt->e_phoff);
  120. for (j = 0; j < epnt->e_phnum; j++, myppnt++) {
  121. if (myppnt->p_type == PT_DYNAMIC) {
  122. tpnt->dynamic_addr = (ElfW(Dyn) *)(myppnt->p_vaddr + load_addr);
  123. tpnt->dynamic_size = myppnt->p_filesz;
  124. }
  125. }
  126. }
  127. brk_addr = 0;
  128. rpnt = NULL;
  129. if (_dl_getenv("LD_BIND_NOW", envp))
  130. unlazy = RTLD_NOW;
  131. /* At this point we are now free to examine the user application,
  132. and figure out which libraries are supposed to be called. Until
  133. we have this list, we will not be completely ready for dynamic linking */
  134. /* Find the runtime load address of the main executable, this may be
  135. * different from what the ELF header says for ET_DYN/PIE executables.
  136. */
  137. {
  138. int i;
  139. ElfW(Phdr) *ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;
  140. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++)
  141. if (ppnt->p_type == PT_PHDR) {
  142. app_tpnt->loadaddr = (ElfW(Addr)) (auxvt[AT_PHDR].a_un.a_val - ppnt->p_vaddr);
  143. break;
  144. }
  145. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  146. if (app_tpnt->loadaddr) {
  147. SEND_STDERR("Position Independent Executable: app_tpnt->loadaddr=");
  148. SEND_ADDRESS_STDERR(app_tpnt->loadaddr, 1);
  149. }
  150. #endif
  151. }
  152. /*
  153. * This is used by gdb to locate the chain of shared libraries that are currently loaded.
  154. */
  155. debug_addr = _dl_malloc(sizeof(struct r_debug));
  156. _dl_memset(debug_addr, 0, sizeof(struct r_debug));
  157. ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;
  158. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
  159. if (ppnt->p_type == PT_LOAD) {
  160. if (ppnt->p_vaddr + app_tpnt->loadaddr + ppnt->p_memsz > brk_addr)
  161. brk_addr = ppnt->p_vaddr + app_tpnt->loadaddr + ppnt->p_memsz;
  162. }
  163. if (ppnt->p_type == PT_DYNAMIC) {
  164. dpnt = (Elf32_Dyn *) (ppnt->p_vaddr + app_tpnt->loadaddr);
  165. while (dpnt->d_tag) {
  166. #if defined(__mips__)
  167. if (dpnt->d_tag == DT_MIPS_GOTSYM)
  168. app_tpnt->mips_gotsym =
  169. (unsigned long) dpnt->d_un.d_val;
  170. if (dpnt->d_tag == DT_MIPS_LOCAL_GOTNO)
  171. app_tpnt->mips_local_gotno =
  172. (unsigned long) dpnt->d_un.d_val;
  173. if (dpnt->d_tag == DT_MIPS_SYMTABNO)
  174. app_tpnt->mips_symtabno =
  175. (unsigned long) dpnt->d_un.d_val;
  176. if (dpnt->d_tag > DT_JMPREL) {
  177. dpnt++;
  178. continue;
  179. }
  180. app_tpnt->dynamic_info[dpnt->d_tag] = dpnt->d_un.d_val;
  181. if (dpnt->d_tag == DT_DEBUG) {
  182. /* Allow writing debug_addr into the .dynamic segment.
  183. * Even though the program header is marked RWE, the kernel gives
  184. * it to us rx.
  185. */
  186. Elf32_Addr mpa = (ppnt->p_vaddr + app_tpnt->loadaddr) & ~(_dl_pagesize - 1);
  187. Elf32_Word mps = ((ppnt->p_vaddr + app_tpnt->loadaddr) - mpa) + ppnt->p_memsz;
  188. if(_dl_mprotect(mpa, mps, PROT_READ | PROT_WRITE | PROT_EXEC)) {
  189. SEND_STDERR("Couldn't mprotect .dynamic segment to rwx.\n");
  190. _dl_exit(0);
  191. }
  192. dpnt->d_un.d_val = (unsigned long) debug_addr;
  193. }
  194. #else
  195. if (dpnt->d_tag > DT_JMPREL) {
  196. dpnt++;
  197. continue;
  198. }
  199. app_tpnt->dynamic_info[dpnt->d_tag] = dpnt->d_un.d_val;
  200. if (dpnt->d_tag == DT_DEBUG) {
  201. dpnt->d_un.d_val = (unsigned long) debug_addr;
  202. }
  203. #endif
  204. if (dpnt->d_tag == DT_TEXTREL)
  205. app_tpnt->dynamic_info[DT_TEXTREL] = 1;
  206. dpnt++;
  207. }
  208. #ifndef FORCE_SHAREABLE_TEXT_SEGMENTS
  209. /* Ugly, ugly. We need to call mprotect to change the protection of
  210. the text pages so that we can do the dynamic linking. We can set the
  211. protection back again once we are done */
  212. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  213. SEND_STDERR("calling mprotect on the application program\n");
  214. #endif
  215. /* Now cover the application program. */
  216. if (app_tpnt->dynamic_info[DT_TEXTREL]) {
  217. ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;
  218. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
  219. if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W))
  220. _dl_mprotect((void *) ((ppnt->p_vaddr + app_tpnt->loadaddr) & PAGE_ALIGN),
  221. ((ppnt->p_vaddr + app_tpnt->loadaddr) & ADDR_ALIGN) +
  222. (unsigned long) ppnt->p_filesz,
  223. PROT_READ | PROT_WRITE | PROT_EXEC);
  224. }
  225. }
  226. #endif
  227. #ifndef ALLOW_ZERO_PLTGOT
  228. /* make sure it's really there. */
  229. if (app_tpnt->dynamic_info[DT_PLTGOT] == 0)
  230. continue;
  231. #endif
  232. /* OK, we have what we need - slip this one into the list. */
  233. app_tpnt = _dl_add_elf_hash_table(_dl_progname, (char *)app_tpnt->loadaddr,
  234. app_tpnt->dynamic_info, ppnt->p_vaddr + app_tpnt->loadaddr, ppnt->p_filesz);
  235. _dl_loaded_modules->libtype = elf_executable;
  236. _dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;
  237. _dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
  238. _dl_symbol_tables = rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  239. _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
  240. rpnt->dyn = _dl_loaded_modules;
  241. app_tpnt->rtld_flags = unlazy | RTLD_GLOBAL;
  242. app_tpnt->usage_count++;
  243. app_tpnt->symbol_scope = _dl_symbol_tables;
  244. lpnt = (unsigned long *) (app_tpnt->dynamic_info[DT_PLTGOT] + app_tpnt->loadaddr);
  245. #ifdef ALLOW_ZERO_PLTGOT
  246. if (lpnt)
  247. #endif
  248. INIT_GOT(lpnt, _dl_loaded_modules);
  249. }
  250. /* OK, fill this in - we did not have this before */
  251. if (ppnt->p_type == PT_INTERP) {
  252. int readsize = 0;
  253. char *pnt, *pnt1, buf[1024];
  254. tpnt->libname = _dl_strdup((char *) ppnt->p_offset +
  255. (auxvt[AT_PHDR].a_un.a_val & PAGE_ALIGN));
  256. /* Determine if the shared lib loader is a symlink */
  257. _dl_memset(buf, 0, sizeof(buf));
  258. readsize = _dl_readlink(tpnt->libname, buf, sizeof(buf));
  259. if (readsize > 0 && readsize < (int)(sizeof(buf)-1)) {
  260. pnt1 = _dl_strrchr(buf, '/');
  261. if (pnt1 && buf != pnt1) {
  262. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  263. _dl_dprintf(_dl_debug_file, "changing tpnt->libname from '%s' to '%s'\n", tpnt->libname, buf);
  264. #endif
  265. tpnt->libname = _dl_strdup(buf);
  266. }
  267. }
  268. /* Store the path where the shared lib loader was found for
  269. * later use */
  270. pnt = _dl_strdup(tpnt->libname);
  271. pnt1 = _dl_strrchr(pnt, '/');
  272. if (pnt != pnt1) {
  273. *pnt1 = '\0';
  274. _dl_ldsopath = pnt;
  275. } else {
  276. _dl_ldsopath = tpnt->libname;
  277. }
  278. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  279. _dl_dprintf(_dl_debug_file, "Lib Loader:\t(%x) %s\n", tpnt->loadaddr, tpnt->libname);
  280. #endif
  281. }
  282. }
  283. /* Now we need to figure out what kind of options are selected.
  284. Note that for SUID programs we ignore the settings in LD_LIBRARY_PATH */
  285. {
  286. if ((auxvt[AT_UID].a_un.a_val == -1 && _dl_suid_ok()) ||
  287. (auxvt[AT_UID].a_un.a_val != -1 &&
  288. auxvt[AT_UID].a_un.a_val == auxvt[AT_EUID].a_un.a_val
  289. && auxvt[AT_GID].a_un.a_val== auxvt[AT_EGID].a_un.a_val)) {
  290. _dl_secure = 0;
  291. _dl_preload = _dl_getenv("LD_PRELOAD", envp);
  292. _dl_library_path = _dl_getenv("LD_LIBRARY_PATH", envp);
  293. } else {
  294. _dl_secure = 1;
  295. _dl_preload = _dl_getenv("LD_PRELOAD", envp);
  296. _dl_unsetenv("LD_AOUT_PRELOAD", envp);
  297. _dl_unsetenv("LD_LIBRARY_PATH", envp);
  298. _dl_unsetenv("LD_AOUT_LIBRARY_PATH", envp);
  299. _dl_library_path = NULL;
  300. }
  301. }
  302. #ifdef __SUPPORT_LD_DEBUG__
  303. _dl_debug = _dl_getenv("LD_DEBUG", envp);
  304. if (_dl_debug)
  305. {
  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 = _dl_strstr(_dl_debug, "all");
  309. }
  310. else {
  311. _dl_debug_detail = _dl_strstr(_dl_debug, "detail");
  312. _dl_debug_move = _dl_strstr(_dl_debug, "move");
  313. _dl_debug_symbols = _dl_strstr(_dl_debug, "sym");
  314. _dl_debug_reloc = _dl_strstr(_dl_debug, "reloc");
  315. _dl_debug_nofixups = _dl_strstr(_dl_debug, "nofix");
  316. _dl_debug_bindings = _dl_strstr(_dl_debug, "bind");
  317. }
  318. }
  319. {
  320. const char *dl_debug_output;
  321. dl_debug_output = _dl_getenv("LD_DEBUG_OUTPUT", envp);
  322. if (dl_debug_output)
  323. {
  324. char tmp[22], *tmp1, *filename;
  325. int len1, len2;
  326. _dl_memset(tmp, 0, sizeof(tmp));
  327. tmp1=_dl_simple_ltoa( tmp, (unsigned long)_dl_getpid());
  328. len1 = _dl_strlen(dl_debug_output);
  329. len2 = _dl_strlen(tmp1);
  330. filename = _dl_malloc(len1+len2+2);
  331. if (filename)
  332. {
  333. _dl_strcpy (filename, dl_debug_output);
  334. filename[len1] = '.';
  335. _dl_strcpy (&filename[len1+1], tmp1);
  336. _dl_debug_file= _dl_open(filename, O_WRONLY|O_CREAT, 0644);
  337. if (_dl_debug_file<0)
  338. {
  339. _dl_debug_file = 2;
  340. _dl_dprintf (2, "can't open file: '%s'\n",filename);
  341. }
  342. }
  343. }
  344. }
  345. #endif
  346. if (_dl_getenv("LD_TRACE_LOADED_OBJECTS", envp) != NULL) {
  347. trace_loaded_objects++;
  348. }
  349. #ifndef __LDSO_LDD_SUPPORT__
  350. if (trace_loaded_objects) {
  351. _dl_dprintf(_dl_debug_file, "Use the ldd provided by uClibc\n");
  352. _dl_exit(1);
  353. }
  354. #endif
  355. /*
  356. * OK, fix one more thing - set up debug_addr so it will point
  357. * to our chain. Later we may need to fill in more fields, but this
  358. * should be enough for now.
  359. */
  360. debug_addr->r_map = (struct link_map *) _dl_loaded_modules;
  361. debug_addr->r_version = 1;
  362. debug_addr->r_ldbase = load_addr;
  363. debug_addr->r_brk = (unsigned long) &_dl_debug_state;
  364. _dl_debug_addr = debug_addr;
  365. /* Notify the debugger we are in a consistant state */
  366. _dl_debug_addr->r_state = RT_CONSISTENT;
  367. _dl_debug_state();
  368. /* OK, we now have the application in the list, and we have some
  369. basic stuff in place. Now search through the list for other shared
  370. libraries that should be loaded, and insert them on the list in the
  371. correct order. */
  372. _dl_map_cache();
  373. if (_dl_preload)
  374. {
  375. char c, *str, *str2;
  376. str = _dl_preload;
  377. while (*str == ':' || *str == ' ' || *str == '\t')
  378. str++;
  379. while (*str)
  380. {
  381. str2 = str;
  382. while (*str2 && *str2 != ':' && *str2 != ' ' && *str2 != '\t')
  383. str2++;
  384. c = *str2;
  385. *str2 = '\0';
  386. if (!_dl_secure || _dl_strchr(str, '/') == NULL)
  387. {
  388. if ((tpnt1 = _dl_check_if_named_library_is_loaded(str, trace_loaded_objects)))
  389. {
  390. tpnt1->usage_count++;
  391. continue;
  392. }
  393. #if defined (__SUPPORT_LD_DEBUG__)
  394. if(_dl_debug) _dl_dprintf(_dl_debug_file, "\tfile='%s'; needed by '%s'\n",
  395. str, _dl_progname);
  396. #endif
  397. tpnt1 = _dl_load_shared_library(_dl_secure, &rpnt, NULL, str, trace_loaded_objects);
  398. if (!tpnt1) {
  399. #ifdef __LDSO_LDD_SUPPORT__
  400. if (trace_loaded_objects)
  401. _dl_dprintf(1, "\t%s => not found\n", str);
  402. else
  403. #endif
  404. {
  405. _dl_dprintf(2, "%s: can't load " "library '%s'\n", _dl_progname, str);
  406. _dl_exit(15);
  407. }
  408. } else {
  409. tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
  410. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  411. _dl_dprintf(_dl_debug_file, "Loading:\t(%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  412. #endif
  413. #ifdef __LDSO_LDD_SUPPORT__
  414. if (trace_loaded_objects && tpnt1->usage_count==1) {
  415. /* this is a real hack to make ldd not print
  416. * the library itself when run on a library. */
  417. if (_dl_strcmp(_dl_progname, str) != 0)
  418. _dl_dprintf(1, "\t%s => %s (%x)\n", str, tpnt1->libname,
  419. (unsigned) tpnt1->loadaddr);
  420. }
  421. #endif
  422. }
  423. }
  424. *str2 = c;
  425. str = str2;
  426. while (*str == ':' || *str == ' ' || *str == '\t')
  427. str++;
  428. }
  429. }
  430. #ifdef SUPPORT_LDSO_PRELOAD_FILE
  431. {
  432. int fd;
  433. struct stat st;
  434. char *preload;
  435. if (!_dl_stat(LDSO_PRELOAD, &st) && st.st_size > 0) {
  436. if ((fd = _dl_open(LDSO_PRELOAD, O_RDONLY, 0)) < 0) {
  437. _dl_dprintf(2, "%s: can't open file '%s'\n",
  438. _dl_progname, LDSO_PRELOAD);
  439. } else {
  440. preload = (caddr_t) _dl_mmap(0, st.st_size + 1,
  441. PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
  442. _dl_close(fd);
  443. if (preload == (caddr_t) - 1) {
  444. _dl_dprintf(2, "%s: can't map file '%s'\n",
  445. _dl_progname, LDSO_PRELOAD);
  446. } else {
  447. char c, *cp, *cp2;
  448. /* convert all separators and comments to spaces */
  449. for (cp = preload; *cp; /*nada */ ) {
  450. if (*cp == ':' || *cp == '\t' || *cp == '\n') {
  451. *cp++ = ' ';
  452. } else if (*cp == '#') {
  453. do
  454. *cp++ = ' ';
  455. while (*cp != '\n' && *cp != '\0');
  456. } else {
  457. cp++;
  458. }
  459. }
  460. /* find start of first library */
  461. for (cp = preload; *cp && *cp == ' '; cp++)
  462. /*nada */ ;
  463. while (*cp) {
  464. /* find end of library */
  465. for (cp2 = cp; *cp && *cp != ' '; cp++)
  466. /*nada */ ;
  467. c = *cp;
  468. *cp = '\0';
  469. if ((tpnt1 = _dl_check_if_named_library_is_loaded(cp2, trace_loaded_objects)))
  470. {
  471. tpnt1->usage_count++;
  472. continue;
  473. }
  474. #if defined (__SUPPORT_LD_DEBUG__)
  475. if(_dl_debug) _dl_dprintf(_dl_debug_file, "\tfile='%s'; needed by '%s'\n",
  476. cp2, _dl_progname);
  477. #endif
  478. tpnt1 = _dl_load_shared_library(0, &rpnt, NULL, cp2, trace_loaded_objects);
  479. if (!tpnt1) {
  480. #ifdef __LDSO_LDD_SUPPORT__
  481. if (trace_loaded_objects)
  482. _dl_dprintf(1, "\t%s => not found\n", cp2);
  483. else
  484. #endif
  485. {
  486. _dl_dprintf(2, "%s: can't load library '%s'\n", _dl_progname, cp2);
  487. _dl_exit(15);
  488. }
  489. } else {
  490. tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
  491. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  492. _dl_dprintf(_dl_debug_file, "Loading:\t(%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  493. #endif
  494. #ifdef __LDSO_LDD_SUPPORT__
  495. if (trace_loaded_objects && tpnt1->usage_count==1) {
  496. _dl_dprintf(1, "\t%s => %s (%x)\n", cp2,
  497. tpnt1->libname, (unsigned) tpnt1->loadaddr);
  498. }
  499. #endif
  500. }
  501. /* find start of next library */
  502. *cp = c;
  503. for ( /*nada */ ; *cp && *cp == ' '; cp++)
  504. /*nada */ ;
  505. }
  506. _dl_munmap(preload, st.st_size + 1);
  507. }
  508. }
  509. }
  510. }
  511. #endif
  512. for (tcurr = _dl_loaded_modules; tcurr; tcurr = tcurr->next)
  513. {
  514. Elf32_Dyn *dpnt;
  515. for (dpnt = (Elf32_Dyn *) tcurr->dynamic_addr; dpnt->d_tag; dpnt++)
  516. {
  517. if (dpnt->d_tag == DT_NEEDED)
  518. {
  519. char *name;
  520. lpntstr = (char*) (tcurr->loadaddr + tcurr->dynamic_info[DT_STRTAB] + dpnt->d_un.d_val);
  521. name = _dl_get_last_path_component(lpntstr);
  522. if ((tpnt1 = _dl_check_if_named_library_is_loaded(name, trace_loaded_objects)))
  523. {
  524. tpnt1->usage_count++;
  525. continue;
  526. }
  527. #if defined (__SUPPORT_LD_DEBUG__)
  528. if(_dl_debug) _dl_dprintf(_dl_debug_file, "\tfile='%s'; needed by '%s'\n",
  529. lpntstr, _dl_progname);
  530. #endif
  531. if (!(tpnt1 = _dl_load_shared_library(0, &rpnt, tcurr, lpntstr, trace_loaded_objects)))
  532. {
  533. #ifdef __LDSO_LDD_SUPPORT__
  534. if (trace_loaded_objects) {
  535. _dl_dprintf(1, "\t%s => not found\n", lpntstr);
  536. continue;
  537. } else
  538. #endif
  539. {
  540. _dl_dprintf(2, "%s: can't load library '%s'\n", _dl_progname, lpntstr);
  541. _dl_exit(16);
  542. }
  543. } else {
  544. tpnt1->rtld_flags = unlazy | RTLD_GLOBAL;
  545. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  546. _dl_dprintf(_dl_debug_file, "Loading:\t(%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  547. #endif
  548. #ifdef __LDSO_LDD_SUPPORT__
  549. if (trace_loaded_objects && tpnt1->usage_count==1) {
  550. _dl_dprintf(1, "\t%s => %s (%x)\n", lpntstr, tpnt1->libname,
  551. (unsigned) tpnt1->loadaddr);
  552. }
  553. #endif
  554. }
  555. }
  556. }
  557. }
  558. _dl_unmap_cache();
  559. /*
  560. * If the program interpreter is not in the module chain, add it. This will
  561. * be required for dlopen to be able to access the internal functions in the
  562. * dynamic linker and to relocate the interpreter again once all libs are loaded.
  563. */
  564. if (tpnt) {
  565. tpnt = _dl_add_elf_hash_table(tpnt->libname, (char *)load_addr, tpnt->dynamic_info,
  566. (unsigned long)tpnt->dynamic_addr, tpnt->dynamic_size);
  567. tpnt->libtype = program_interpreter;
  568. tpnt->usage_count++;
  569. tpnt->symbol_scope = _dl_symbol_tables;
  570. if (rpnt) {
  571. rpnt->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  572. _dl_memset(rpnt->next, 0, sizeof(struct dyn_elf));
  573. rpnt->next->prev = rpnt;
  574. rpnt = rpnt->next;
  575. } else {
  576. rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  577. _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
  578. }
  579. rpnt->dyn = tpnt;
  580. tpnt->rtld_flags = RTLD_NOW | RTLD_GLOBAL; /* Must not be LAZY */
  581. #ifdef RERELOCATE_LDSO
  582. /* Only rerelocate functions for now. */
  583. tpnt->init_flag = RELOCS_DONE | COPY_RELOCS_DONE;
  584. lpnt = (unsigned long *) (tpnt->dynamic_info[DT_PLTGOT] + load_addr);
  585. # ifdef ALLOW_ZERO_PLTGOT
  586. if (tpnt->dynamic_info[DT_PLTGOT])
  587. # endif
  588. INIT_GOT(lpnt, tpnt);
  589. #else
  590. tpnt->init_flag = RELOCS_DONE | JMP_RELOCS_DONE | COPY_RELOCS_DONE;
  591. #endif
  592. tpnt = NULL;
  593. }
  594. #ifdef __LDSO_LDD_SUPPORT__
  595. /* End of the line for ldd.... */
  596. if (trace_loaded_objects) {
  597. _dl_dprintf(1, "\t%s => %s (%x)\n", rpnt->dyn->libname + (_dl_strlen(_dl_ldsopath)) + 1,
  598. rpnt->dyn->libname, rpnt->dyn->loadaddr);
  599. _dl_exit(0);
  600. }
  601. #endif
  602. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  603. _dl_dprintf(_dl_debug_file, "Beginning relocation fixups\n");
  604. #endif
  605. #ifdef __mips__
  606. /*
  607. * Relocation of the GOT entries for MIPS have to be done
  608. * after all the libraries have been loaded. */
  609. _dl_perform_mips_global_got_relocations(_dl_loaded_modules);
  610. #endif
  611. /*
  612. * OK, now all of the kids are tucked into bed in their proper addresses.
  613. * Now we go through and look for REL and RELA records that indicate fixups
  614. * to the GOT tables. We need to do this in reverse order so that COPY
  615. * directives work correctly */
  616. if (_dl_symbol_tables)
  617. goof += _dl_fixup(_dl_symbol_tables, unlazy);
  618. /* OK, at this point things are pretty much ready to run. Now we
  619. need to touch up a few items that are required, and then
  620. we can let the user application have at it. Note that
  621. the dynamic linker itself is not guaranteed to be fully
  622. dynamicly linked if we are using ld.so.1, so we have to look
  623. up each symbol individually. */
  624. #ifndef FORCE_SHAREABLE_TEXT_SEGMENTS
  625. {
  626. unsigned int j;
  627. ElfW(Phdr) *myppnt;
  628. /* We had to set the protections of all pages to R/W for dynamic linking.
  629. Set text pages back to R/O */
  630. for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
  631. for (myppnt = tpnt->ppnt, j = 0; j < tpnt->n_phent; j++, myppnt++) {
  632. if (myppnt->p_type == PT_LOAD && !(myppnt->p_flags & PF_W) && tpnt->dynamic_info[DT_TEXTREL]) {
  633. _dl_mprotect((void *) (tpnt->loadaddr + (myppnt->p_vaddr & PAGE_ALIGN)),
  634. (myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz, LXFLAGS(myppnt->p_flags));
  635. }
  636. }
  637. }
  638. }
  639. #endif
  640. _dl_atexit = (int (*)(void *)) (intptr_t) _dl_find_hash("atexit", _dl_symbol_tables, ELF_RTYPE_CLASS_PLT);
  641. #if defined (__SUPPORT_LD_DEBUG__)
  642. _dl_on_exit = (int (*)(void (*)(int, void *),void*))
  643. (intptr_t) _dl_find_hash("on_exit", _dl_symbol_tables, ELF_RTYPE_CLASS_PLT);
  644. #endif
  645. /* Notify the debugger we have added some objects. */
  646. _dl_debug_addr->r_state = RT_ADD;
  647. _dl_debug_state();
  648. for (rpnt = _dl_symbol_tables; rpnt!=NULL&& rpnt->next!=NULL; rpnt=rpnt->next)
  649. ;
  650. for (;rpnt!=NULL; rpnt=rpnt->prev)
  651. {
  652. tpnt = rpnt->dyn;
  653. if (tpnt->libtype == program_interpreter)
  654. continue;
  655. /* Apparently crt0/1 for the application is responsible for handling this.
  656. * We only need to run the init/fini for shared libraries
  657. */
  658. if (tpnt->libtype == elf_executable)
  659. break; /* at this point all shared libs are initialized !! */
  660. if (tpnt->init_flag & INIT_FUNCS_CALLED)
  661. continue;
  662. tpnt->init_flag |= INIT_FUNCS_CALLED;
  663. if (tpnt->dynamic_info[DT_INIT]) {
  664. void (*dl_elf_func) (void);
  665. dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
  666. #if defined (__SUPPORT_LD_DEBUG__)
  667. if(_dl_debug) _dl_dprintf(_dl_debug_file,"\ncalling init: %s\n\n", tpnt->libname);
  668. #endif
  669. (*dl_elf_func) ();
  670. }
  671. if (_dl_atexit && tpnt->dynamic_info[DT_FINI]) {
  672. void (*dl_elf_func) (void);
  673. dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
  674. (*_dl_atexit) (dl_elf_func);
  675. #if defined (__SUPPORT_LD_DEBUG__)
  676. if(_dl_debug && _dl_on_exit)
  677. {
  678. (*_dl_on_exit)(debug_fini, tpnt->libname);
  679. }
  680. #endif
  681. }
  682. #if defined (__SUPPORT_LD_DEBUG__)
  683. else {
  684. if (!_dl_atexit)
  685. _dl_dprintf(_dl_debug_file, "%s: The address of atexit () is 0x0.\n", tpnt->libname);
  686. #if 0
  687. if (!tpnt->dynamic_info[DT_FINI])
  688. _dl_dprintf(_dl_debug_file, "%s: Invalid .fini section.\n", tpnt->libname);
  689. #endif
  690. }
  691. #endif
  692. }
  693. /* Notify the debugger that all objects are now mapped in. */
  694. _dl_debug_addr->r_state = RT_CONSISTENT;
  695. _dl_debug_state();
  696. /* Find the real malloc function and make ldso functions use that from now on */
  697. _dl_malloc_function = (void (*)(size_t)) (intptr_t) _dl_find_hash("malloc", _dl_symbol_tables, ELF_RTYPE_CLASS_PLT);
  698. }
  699. char *_dl_getenv(const char *symbol, char **envp)
  700. {
  701. char *pnt;
  702. const char *pnt1;
  703. while ((pnt = *envp++)) {
  704. pnt1 = symbol;
  705. while (*pnt && *pnt == *pnt1)
  706. pnt1++, pnt++;
  707. if (!*pnt || *pnt != '=' || *pnt1)
  708. continue;
  709. return pnt + 1;
  710. }
  711. return 0;
  712. }
  713. void _dl_unsetenv(const char *symbol, char **envp)
  714. {
  715. char *pnt;
  716. const char *pnt1;
  717. char **newenvp = envp;
  718. for (pnt = *envp; pnt; pnt = *++envp) {
  719. pnt1 = symbol;
  720. while (*pnt && *pnt == *pnt1)
  721. pnt1++, pnt++;
  722. if (!*pnt || *pnt != '=' || *pnt1)
  723. *newenvp++ = *envp;
  724. }
  725. *newenvp++ = *envp;
  726. return;
  727. }
  728. static int _dl_suid_ok(void)
  729. {
  730. __kernel_uid_t uid, euid;
  731. __kernel_gid_t gid, egid;
  732. uid = _dl_getuid();
  733. euid = _dl_geteuid();
  734. gid = _dl_getgid();
  735. egid = _dl_getegid();
  736. if(uid == euid && gid == egid) {
  737. return 1;
  738. }
  739. return 0;
  740. }
  741. void *_dl_malloc(int size)
  742. {
  743. void *retval;
  744. #if 0
  745. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  746. _dl_dprintf(2, "malloc: request for %d bytes\n", size);
  747. #endif
  748. #endif
  749. if (_dl_malloc_function)
  750. return (*_dl_malloc_function) (size);
  751. if (_dl_malloc_addr - _dl_mmap_zero + (unsigned)size > _dl_pagesize) {
  752. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  753. _dl_dprintf(2, "malloc: mmapping more memory\n");
  754. #endif
  755. _dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, size,
  756. PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  757. if (_dl_mmap_check_error(_dl_mmap_zero)) {
  758. _dl_dprintf(2, "%s: mmap of a spare page failed!\n", _dl_progname);
  759. _dl_exit(20);
  760. }
  761. }
  762. retval = _dl_malloc_addr;
  763. _dl_malloc_addr += size;
  764. /*
  765. * Align memory to 4 byte boundary. Some platforms require this, others
  766. * simply get better performance.
  767. */
  768. _dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + 3) & ~(3));
  769. return retval;
  770. }
  771. #include "dl-hash.c"
  772. #include "dl-elf.c"