ldso.c 22 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. unsigned char *_dl_malloc_addr = 0; /* Lets _dl_malloc use the already allocated memory page */
  40. unsigned char *_dl_mmap_zero = 0; /* Also used by _dl_malloc */
  41. unsigned long *_dl_brkp = 0; /* The end of the data segment for brk and sbrk */
  42. unsigned long *_dl_envp = 0; /* The environment address */
  43. int _dl_secure = 1; /* Are we dealing with setuid stuff? */
  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. /* This global variable is also to communicate with debuggers such as gdb. */
  65. struct r_debug *_dl_debug_addr = NULL;
  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, struct elf_resolve *app_tpnt,
  74. unsigned long load_addr, unsigned long *hash_addr,
  75. Elf32_auxv_t auxvt[AT_EGID + 1], char **envp, struct r_debug *debug_addr,
  76. unsigned char *malloc_buffer, unsigned char *mmap_zero, char **argv)
  77. {
  78. ElfW(Phdr) *ppnt;
  79. char *lpntstr;
  80. int i, goof = 0, be_lazy = RTLD_LAZY, trace_loaded_objects = 0;
  81. struct dyn_elf *rpnt;
  82. struct elf_resolve *tcurr;
  83. struct elf_resolve *tpnt1;
  84. unsigned long brk_addr, *lpnt;
  85. int (*_dl_atexit) (void *);
  86. #if defined (__SUPPORT_LD_DEBUG__)
  87. int (*_dl_on_exit) (void (*FUNCTION)(int STATUS, void *ARG),void*);
  88. #endif
  89. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  90. /* Wahoo!!! */
  91. SEND_STDERR("Cool, we managed to make a function call.\n");
  92. #endif
  93. /* Make it so _dl_malloc can use the page of memory we have already
  94. * allocated. We shouldn't need to grab any more memory. This must
  95. * be first since things like _dl_dprintf() use _dl_malloc().... */
  96. _dl_malloc_addr = malloc_buffer;
  97. _dl_mmap_zero = mmap_zero;
  98. /* Now we have done the mandatory linking of some things. We are now
  99. * free to start using global variables, since these things have all been
  100. * fixed up by now. Still no function calls outside of this library ,
  101. * since the dynamic resolver is not yet ready. */
  102. if (argv[0]) {
  103. _dl_progname = argv[0];
  104. }
  105. /* Start to build the tables of the modules that are required for
  106. * this beast to run. We start with the basic executable, and then
  107. * go from there. Eventually we will run across ourself, and we
  108. * will need to properly deal with that as well. */
  109. lpnt = (unsigned long *) (tpnt->dynamic_info[DT_PLTGOT] + load_addr);
  110. tpnt->chains = hash_addr;
  111. tpnt->next = 0;
  112. tpnt->libname = 0;
  113. tpnt->libtype = program_interpreter;
  114. tpnt->loadaddr = (ElfW(Addr)) load_addr;
  115. #ifdef ALLOW_ZERO_PLTGOT
  116. if (tpnt->dynamic_info[DT_PLTGOT])
  117. #endif
  118. {
  119. INIT_GOT(lpnt, tpnt);
  120. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  121. _dl_dprintf(_dl_debug_file, "GOT found at %x\n", lpnt);
  122. #endif
  123. }
  124. /* OK, this was a big step, now we need to scan all of the user images
  125. and load them properly. */
  126. {
  127. ElfW(Ehdr) *epnt;
  128. ElfW(Phdr) *myppnt;
  129. int j;
  130. epnt = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_ptr;
  131. tpnt->n_phent = epnt->e_phnum;
  132. tpnt->ppnt = myppnt = (ElfW(Phdr) *) (load_addr + epnt->e_phoff);
  133. for (j = 0; j < epnt->e_phnum; j++, myppnt++) {
  134. if (myppnt->p_type == PT_DYNAMIC) {
  135. tpnt->dynamic_addr = (ElfW(Dyn) *)myppnt->p_vaddr + load_addr;
  136. tpnt->dynamic_size = myppnt->p_filesz;
  137. }
  138. }
  139. }
  140. brk_addr = 0;
  141. rpnt = NULL;
  142. /* At this point we are now free to examine the user application,
  143. and figure out which libraries are supposed to be called. Until
  144. we have this list, we will not be completely ready for dynamic linking */
  145. ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;
  146. for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
  147. if (ppnt->p_type == PT_LOAD) {
  148. #ifndef __UCLIBC_PIE_SUPPORT__
  149. if (ppnt->p_vaddr + ppnt->p_memsz > brk_addr)
  150. brk_addr = ppnt->p_vaddr + ppnt->p_memsz;
  151. #else
  152. if (ppnt->p_vaddr + app_tpnt->loadaddr + ppnt->p_memsz > brk_addr)
  153. brk_addr = ppnt->p_vaddr + app_tpnt->loadaddr + ppnt->p_memsz;
  154. #endif
  155. }
  156. if (ppnt->p_type == PT_DYNAMIC) {
  157. #ifndef ALLOW_ZERO_PLTGOT
  158. /* make sure it's really there. */
  159. if (app_tpnt->dynamic_info[DT_PLTGOT] == 0)
  160. continue;
  161. #endif
  162. /* OK, we have what we need - slip this one into the list. */
  163. #ifndef __UCLIBC_PIE_SUPPORT__
  164. app_tpnt = _dl_add_elf_hash_table("", 0,
  165. app_tpnt->dynamic_info, ppnt->p_vaddr, ppnt->p_filesz);
  166. #else
  167. app_tpnt = _dl_add_elf_hash_table("", (char *)app_tpnt->loadaddr,
  168. app_tpnt->dynamic_info, ppnt->p_vaddr + app_tpnt->loadaddr, ppnt->p_filesz);
  169. #endif
  170. _dl_loaded_modules->libtype = elf_executable;
  171. _dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;
  172. _dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
  173. _dl_symbol_tables = rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  174. _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
  175. rpnt->dyn = _dl_loaded_modules;
  176. app_tpnt->usage_count++;
  177. app_tpnt->symbol_scope = _dl_symbol_tables;
  178. #ifndef __UCLIBC_PIE_SUPPORT__
  179. lpnt = (unsigned long *) (app_tpnt->dynamic_info[DT_PLTGOT]);
  180. #else
  181. lpnt = (unsigned long *) (app_tpnt->dynamic_info[DT_PLTGOT] + app_tpnt->loadaddr);
  182. #endif
  183. #ifdef ALLOW_ZERO_PLTGOT
  184. if (lpnt)
  185. #endif
  186. INIT_GOT(lpnt, _dl_loaded_modules);
  187. }
  188. /* OK, fill this in - we did not have this before */
  189. if (ppnt->p_type == PT_INTERP) {
  190. int readsize = 0;
  191. char *pnt, *pnt1, buf[1024];
  192. tpnt->libname = _dl_strdup((char *) ppnt->p_offset +
  193. (auxvt[AT_PHDR].a_un.a_val & PAGE_ALIGN));
  194. /* Determine if the shared lib loader is a symlink */
  195. _dl_memset(buf, 0, sizeof(buf));
  196. readsize = _dl_readlink(tpnt->libname, buf, sizeof(buf));
  197. if (readsize > 0 && readsize < (int)(sizeof(buf)-1)) {
  198. pnt1 = _dl_strrchr(buf, '/');
  199. if (pnt1 && buf != pnt1) {
  200. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  201. _dl_dprintf(_dl_debug_file, "changing tpnt->libname from '%s' to '%s'\n", tpnt->libname, buf);
  202. #endif
  203. tpnt->libname = _dl_strdup(buf);
  204. }
  205. }
  206. /* Store the path where the shared lib loader was found for
  207. * later use */
  208. pnt = _dl_strdup(tpnt->libname);
  209. pnt1 = _dl_strrchr(pnt, '/');
  210. if (pnt != pnt1) {
  211. *pnt1 = '\0';
  212. _dl_ldsopath = pnt;
  213. } else {
  214. _dl_ldsopath = tpnt->libname;
  215. }
  216. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  217. _dl_dprintf(_dl_debug_file, "Lib Loader:\t(%x) %s\n", tpnt->loadaddr, tpnt->libname);
  218. #endif
  219. }
  220. }
  221. /* Now we need to figure out what kind of options are selected.
  222. Note that for SUID programs we ignore the settings in LD_LIBRARY_PATH */
  223. {
  224. if (_dl_getenv("LD_BIND_NOW", envp))
  225. be_lazy = 0;
  226. if ((auxvt[AT_UID].a_un.a_val == -1 && _dl_suid_ok()) ||
  227. (auxvt[AT_UID].a_un.a_val != -1 &&
  228. auxvt[AT_UID].a_un.a_val == auxvt[AT_EUID].a_un.a_val
  229. && auxvt[AT_GID].a_un.a_val== auxvt[AT_EGID].a_un.a_val)) {
  230. _dl_secure = 0;
  231. _dl_preload = _dl_getenv("LD_PRELOAD", envp);
  232. _dl_library_path = _dl_getenv("LD_LIBRARY_PATH", envp);
  233. } else {
  234. _dl_secure = 1;
  235. _dl_preload = _dl_getenv("LD_PRELOAD", envp);
  236. _dl_unsetenv("LD_AOUT_PRELOAD", envp);
  237. _dl_unsetenv("LD_LIBRARY_PATH", envp);
  238. _dl_unsetenv("LD_AOUT_LIBRARY_PATH", envp);
  239. _dl_library_path = NULL;
  240. }
  241. }
  242. #ifdef __SUPPORT_LD_DEBUG__
  243. _dl_debug = _dl_getenv("LD_DEBUG", envp);
  244. if (_dl_debug)
  245. {
  246. if (_dl_strstr(_dl_debug, "all")) {
  247. _dl_debug_detail = _dl_debug_move = _dl_debug_symbols
  248. = _dl_debug_reloc = _dl_debug_bindings = _dl_debug_nofixups = _dl_strstr(_dl_debug, "all");
  249. }
  250. else {
  251. _dl_debug_detail = _dl_strstr(_dl_debug, "detail");
  252. _dl_debug_move = _dl_strstr(_dl_debug, "move");
  253. _dl_debug_symbols = _dl_strstr(_dl_debug, "sym");
  254. _dl_debug_reloc = _dl_strstr(_dl_debug, "reloc");
  255. _dl_debug_nofixups = _dl_strstr(_dl_debug, "nofix");
  256. _dl_debug_bindings = _dl_strstr(_dl_debug, "bind");
  257. }
  258. }
  259. {
  260. const char *dl_debug_output;
  261. dl_debug_output = _dl_getenv("LD_DEBUG_OUTPUT", envp);
  262. if (dl_debug_output)
  263. {
  264. char tmp[22], *tmp1, *filename;
  265. int len1, len2;
  266. _dl_memset(tmp, 0, sizeof(tmp));
  267. tmp1=_dl_simple_ltoa( tmp, (unsigned long)_dl_getpid());
  268. len1 = _dl_strlen(dl_debug_output);
  269. len2 = _dl_strlen(tmp1);
  270. filename = _dl_malloc(len1+len2+2);
  271. if (filename)
  272. {
  273. _dl_strcpy (filename, dl_debug_output);
  274. filename[len1] = '.';
  275. _dl_strcpy (&filename[len1+1], tmp1);
  276. _dl_debug_file= _dl_open(filename, O_WRONLY|O_CREAT, 0644);
  277. if (_dl_debug_file<0)
  278. {
  279. _dl_debug_file = 2;
  280. _dl_dprintf (2, "can't open file: '%s'\n",filename);
  281. }
  282. }
  283. }
  284. }
  285. #endif
  286. if (_dl_getenv("LD_TRACE_LOADED_OBJECTS", envp) != NULL) {
  287. trace_loaded_objects++;
  288. }
  289. #ifndef __LDSO_LDD_SUPPORT__
  290. if (trace_loaded_objects) {
  291. _dl_dprintf(_dl_debug_file, "Use the ldd provided by uClibc\n");
  292. _dl_exit(1);
  293. }
  294. #endif
  295. /*
  296. * OK, fix one more thing - set up debug_addr so it will point
  297. * to our chain. Later we may need to fill in more fields, but this
  298. * should be enough for now.
  299. */
  300. debug_addr->r_map = (struct link_map *) _dl_loaded_modules;
  301. debug_addr->r_version = 1;
  302. debug_addr->r_ldbase = load_addr;
  303. debug_addr->r_brk = (unsigned long) &_dl_debug_state;
  304. _dl_debug_addr = debug_addr;
  305. /* Notify the debugger we are in a consistant state */
  306. _dl_debug_addr->r_state = RT_CONSISTENT;
  307. _dl_debug_state();
  308. /* OK, we now have the application in the list, and we have some
  309. basic stuff in place. Now search through the list for other shared
  310. libraries that should be loaded, and insert them on the list in the
  311. correct order. */
  312. _dl_map_cache();
  313. if (_dl_preload)
  314. {
  315. char c, *str, *str2;
  316. str = _dl_preload;
  317. while (*str == ':' || *str == ' ' || *str == '\t')
  318. str++;
  319. while (*str)
  320. {
  321. str2 = str;
  322. while (*str2 && *str2 != ':' && *str2 != ' ' && *str2 != '\t')
  323. str2++;
  324. c = *str2;
  325. *str2 = '\0';
  326. if (!_dl_secure || _dl_strchr(str, '/') == NULL)
  327. {
  328. if ((tpnt1 = _dl_check_if_named_library_is_loaded(str, trace_loaded_objects)))
  329. {
  330. continue;
  331. }
  332. #if defined (__SUPPORT_LD_DEBUG__)
  333. if(_dl_debug) _dl_dprintf(_dl_debug_file, "\tfile='%s'; needed by '%s'\n",
  334. str, _dl_progname);
  335. #endif
  336. tpnt1 = _dl_load_shared_library(_dl_secure, &rpnt, NULL, str, trace_loaded_objects);
  337. if (!tpnt1) {
  338. #ifdef __LDSO_LDD_SUPPORT__
  339. if (trace_loaded_objects)
  340. _dl_dprintf(1, "\t%s => not found\n", str);
  341. else
  342. #endif
  343. {
  344. _dl_dprintf(2, "%s: can't load " "library '%s'\n", _dl_progname, str);
  345. _dl_exit(15);
  346. }
  347. } else {
  348. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  349. _dl_dprintf(_dl_debug_file, "Loading:\t(%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  350. #endif
  351. #ifdef __LDSO_LDD_SUPPORT__
  352. if (trace_loaded_objects && tpnt1->usage_count==1) {
  353. /* this is a real hack to make ldd not print
  354. * the library itself when run on a library. */
  355. if (_dl_strcmp(_dl_progname, str) != 0)
  356. _dl_dprintf(1, "\t%s => %s (%x)\n", str, tpnt1->libname,
  357. (unsigned) tpnt1->loadaddr);
  358. }
  359. #endif
  360. }
  361. }
  362. *str2 = c;
  363. str = str2;
  364. while (*str == ':' || *str == ' ' || *str == '\t')
  365. str++;
  366. }
  367. }
  368. #ifdef SUPPORT_LDSO_PRELOAD_FILE
  369. {
  370. int fd;
  371. struct stat st;
  372. char *preload;
  373. if (!_dl_stat(LDSO_PRELOAD, &st) && st.st_size > 0) {
  374. if ((fd = _dl_open(LDSO_PRELOAD, O_RDONLY, 0)) < 0) {
  375. _dl_dprintf(2, "%s: can't open file '%s'\n",
  376. _dl_progname, LDSO_PRELOAD);
  377. } else {
  378. preload = (caddr_t) _dl_mmap(0, st.st_size + 1,
  379. PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
  380. _dl_close(fd);
  381. if (preload == (caddr_t) - 1) {
  382. _dl_dprintf(2, "%s: can't map file '%s'\n",
  383. _dl_progname, LDSO_PRELOAD);
  384. } else {
  385. char c, *cp, *cp2;
  386. /* convert all separators and comments to spaces */
  387. for (cp = preload; *cp; /*nada */ ) {
  388. if (*cp == ':' || *cp == '\t' || *cp == '\n') {
  389. *cp++ = ' ';
  390. } else if (*cp == '#') {
  391. do
  392. *cp++ = ' ';
  393. while (*cp != '\n' && *cp != '\0');
  394. } else {
  395. cp++;
  396. }
  397. }
  398. /* find start of first library */
  399. for (cp = preload; *cp && *cp == ' '; cp++)
  400. /*nada */ ;
  401. while (*cp) {
  402. /* find end of library */
  403. for (cp2 = cp; *cp && *cp != ' '; cp++)
  404. /*nada */ ;
  405. c = *cp;
  406. *cp = '\0';
  407. if ((tpnt1 = _dl_check_if_named_library_is_loaded(cp2, trace_loaded_objects)))
  408. {
  409. continue;
  410. }
  411. #if defined (__SUPPORT_LD_DEBUG__)
  412. if(_dl_debug) _dl_dprintf(_dl_debug_file, "\tfile='%s'; needed by '%s'\n",
  413. cp2, _dl_progname);
  414. #endif
  415. tpnt1 = _dl_load_shared_library(0, &rpnt, NULL, cp2, trace_loaded_objects);
  416. if (!tpnt1) {
  417. #ifdef __LDSO_LDD_SUPPORT__
  418. if (trace_loaded_objects)
  419. _dl_dprintf(1, "\t%s => not found\n", cp2);
  420. else
  421. #endif
  422. {
  423. _dl_dprintf(2, "%s: can't load library '%s'\n", _dl_progname, cp2);
  424. _dl_exit(15);
  425. }
  426. } else {
  427. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  428. _dl_dprintf(_dl_debug_file, "Loading:\t(%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  429. #endif
  430. #ifdef __LDSO_LDD_SUPPORT__
  431. if (trace_loaded_objects && tpnt1->usage_count==1) {
  432. _dl_dprintf(1, "\t%s => %s (%x)\n", cp2,
  433. tpnt1->libname, (unsigned) tpnt1->loadaddr);
  434. }
  435. #endif
  436. }
  437. /* find start of next library */
  438. *cp = c;
  439. for ( /*nada */ ; *cp && *cp == ' '; cp++)
  440. /*nada */ ;
  441. }
  442. _dl_munmap(preload, st.st_size + 1);
  443. }
  444. }
  445. }
  446. }
  447. #endif
  448. for (tcurr = _dl_loaded_modules; tcurr; tcurr = tcurr->next)
  449. {
  450. Elf32_Dyn *dpnt;
  451. for (dpnt = (Elf32_Dyn *) tcurr->dynamic_addr; dpnt->d_tag; dpnt++)
  452. {
  453. if (dpnt->d_tag == DT_NEEDED)
  454. {
  455. char *name;
  456. lpntstr = (char*) (tcurr->loadaddr + tcurr->dynamic_info[DT_STRTAB] + dpnt->d_un.d_val);
  457. name = _dl_get_last_path_component(lpntstr);
  458. if ((tpnt1 = _dl_check_if_named_library_is_loaded(name, trace_loaded_objects)))
  459. {
  460. continue;
  461. }
  462. #if defined (__SUPPORT_LD_DEBUG__)
  463. if(_dl_debug) _dl_dprintf(_dl_debug_file, "\tfile='%s'; needed by '%s'\n",
  464. lpntstr, _dl_progname);
  465. #endif
  466. if (!(tpnt1 = _dl_load_shared_library(0, &rpnt, tcurr, lpntstr, trace_loaded_objects)))
  467. {
  468. #ifdef __LDSO_LDD_SUPPORT__
  469. if (trace_loaded_objects) {
  470. _dl_dprintf(1, "\t%s => not found\n", lpntstr);
  471. continue;
  472. } else
  473. #endif
  474. {
  475. _dl_dprintf(2, "%s: can't load library '%s'\n", _dl_progname, lpntstr);
  476. _dl_exit(16);
  477. }
  478. } else {
  479. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  480. _dl_dprintf(_dl_debug_file, "Loading:\t(%x) %s\n", tpnt1->loadaddr, tpnt1->libname);
  481. #endif
  482. #ifdef __LDSO_LDD_SUPPORT__
  483. if (trace_loaded_objects && tpnt1->usage_count==1) {
  484. _dl_dprintf(1, "\t%s => %s (%x)\n", lpntstr, tpnt1->libname,
  485. (unsigned) tpnt1->loadaddr);
  486. }
  487. #endif
  488. }
  489. }
  490. }
  491. }
  492. _dl_unmap_cache();
  493. /*
  494. * If the program interpreter is not in the module chain, add it. This will
  495. * be required for dlopen to be able to access the internal functions in the
  496. * dynamic linker.
  497. */
  498. if (tpnt) {
  499. tcurr = _dl_loaded_modules;
  500. if (tcurr)
  501. while (tcurr->next)
  502. tcurr = tcurr->next;
  503. tpnt->next = NULL;
  504. tpnt->usage_count++;
  505. if (tcurr) {
  506. tcurr->next = tpnt;
  507. tpnt->prev = tcurr;
  508. } else {
  509. _dl_loaded_modules = tpnt;
  510. tpnt->prev = NULL;
  511. }
  512. if (rpnt) {
  513. rpnt->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  514. _dl_memset(rpnt->next, 0, sizeof(struct dyn_elf));
  515. rpnt->next->prev = rpnt;
  516. rpnt = rpnt->next;
  517. } else {
  518. rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
  519. _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
  520. }
  521. rpnt->dyn = tpnt;
  522. tpnt = NULL;
  523. }
  524. #ifdef __LDSO_LDD_SUPPORT__
  525. /* End of the line for ldd.... */
  526. if (trace_loaded_objects) {
  527. _dl_dprintf(1, "\t%s => %s (%x)\n", rpnt->dyn->libname + (_dl_strlen(_dl_ldsopath)) + 1,
  528. rpnt->dyn->libname, rpnt->dyn->loadaddr);
  529. _dl_exit(0);
  530. }
  531. #endif
  532. #ifdef __mips__
  533. /*
  534. * Relocation of the GOT entries for MIPS have to be done
  535. * after all the libraries have been loaded.
  536. */
  537. _dl_perform_mips_global_got_relocations(_dl_loaded_modules);
  538. #endif
  539. #ifdef __SUPPORT_LD_DEBUG_EARLY__
  540. _dl_dprintf(_dl_debug_file, "Beginning relocation fixups\n");
  541. #endif
  542. /*
  543. * OK, now all of the kids are tucked into bed in their proper addresses.
  544. * Now we go through and look for REL and RELA records that indicate fixups
  545. * to the GOT tables. We need to do this in reverse order so that COPY
  546. * directives work correctly */
  547. if (_dl_symbol_tables)
  548. goof += _dl_fixup(_dl_symbol_tables, be_lazy);
  549. /* OK, at this point things are pretty much ready to run. Now we
  550. need to touch up a few items that are required, and then
  551. we can let the user application have at it. Note that
  552. the dynamic linker itself is not guaranteed to be fully
  553. dynamicly linked if we are using ld.so.1, so we have to look
  554. up each symbol individually. */
  555. _dl_brkp = (unsigned long *) (intptr_t) _dl_find_hash("___brk_addr", NULL, NULL, symbolrel);
  556. if (_dl_brkp) {
  557. *_dl_brkp = brk_addr;
  558. }
  559. _dl_envp = (unsigned long *) (intptr_t) _dl_find_hash("__environ", NULL, NULL, symbolrel);
  560. if (_dl_envp) {
  561. *_dl_envp = (unsigned long) envp;
  562. }
  563. #ifndef FORCE_SHAREABLE_TEXT_SEGMENTS
  564. {
  565. unsigned int j;
  566. ElfW(Phdr) *myppnt;
  567. /* We had to set the protections of all pages to R/W for dynamic linking.
  568. Set text pages back to R/O */
  569. for (tpnt = _dl_loaded_modules; tpnt; tpnt = tpnt->next) {
  570. for (myppnt = tpnt->ppnt, j = 0; j < tpnt->n_phent; j++, myppnt++) {
  571. if (myppnt->p_type == PT_LOAD && !(myppnt->p_flags & PF_W) && tpnt->dynamic_info[DT_TEXTREL]) {
  572. _dl_mprotect((void *) (tpnt->loadaddr + (myppnt->p_vaddr & PAGE_ALIGN)),
  573. (myppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) myppnt->p_filesz, LXFLAGS(myppnt->p_flags));
  574. }
  575. }
  576. }
  577. }
  578. #endif
  579. _dl_atexit = (int (*)(void *)) (intptr_t) _dl_find_hash("atexit", NULL, NULL, symbolrel);
  580. #if defined (__SUPPORT_LD_DEBUG__)
  581. _dl_on_exit = (int (*)(void (*)(int, void *),void*))
  582. (intptr_t) _dl_find_hash("on_exit", NULL, NULL, symbolrel);
  583. #endif
  584. /* Notify the debugger we have added some objects. */
  585. _dl_debug_addr->r_state = RT_ADD;
  586. _dl_debug_state();
  587. for (rpnt = _dl_symbol_tables; rpnt!=NULL&& rpnt->next!=NULL; rpnt=rpnt->next)
  588. ;
  589. for (;rpnt!=NULL; rpnt=rpnt->prev)
  590. {
  591. tpnt = rpnt->dyn;
  592. if (tpnt->libtype == program_interpreter)
  593. continue;
  594. /* Apparently crt0/1 for the application is responsible for handling this.
  595. * We only need to run the init/fini for shared libraries
  596. */
  597. if (tpnt->libtype == elf_executable)
  598. break; /* at this point all shared libs are initialized !! */
  599. if (tpnt->init_flag & INIT_FUNCS_CALLED)
  600. continue;
  601. tpnt->init_flag |= INIT_FUNCS_CALLED;
  602. if (tpnt->dynamic_info[DT_INIT]) {
  603. void (*dl_elf_func) (void);
  604. dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_INIT]);
  605. #if defined (__SUPPORT_LD_DEBUG__)
  606. if(_dl_debug) _dl_dprintf(_dl_debug_file,"\ncalling init: %s\n\n", tpnt->libname);
  607. #endif
  608. (*dl_elf_func) ();
  609. }
  610. if (_dl_atexit && tpnt->dynamic_info[DT_FINI]) {
  611. void (*dl_elf_func) (void);
  612. dl_elf_func = (void (*)(void)) (intptr_t) (tpnt->loadaddr + tpnt->dynamic_info[DT_FINI]);
  613. (*_dl_atexit) (dl_elf_func);
  614. #if defined (__SUPPORT_LD_DEBUG__)
  615. if(_dl_debug && _dl_on_exit)
  616. {
  617. (*_dl_on_exit)(debug_fini, tpnt->libname);
  618. }
  619. #endif
  620. }
  621. #if defined (__SUPPORT_LD_DEBUG__)
  622. else {
  623. if (!_dl_atexit)
  624. _dl_dprintf(_dl_debug_file, "%s: The address of atexit () is 0x0.\n", tpnt->libname);
  625. #if 0
  626. if (!tpnt->dynamic_info[DT_FINI])
  627. _dl_dprintf(_dl_debug_file, "%s: Invalid .fini section.\n", tpnt->libname);
  628. #endif
  629. }
  630. #endif
  631. }
  632. /* Notify the debugger that all objects are now mapped in. */
  633. _dl_debug_addr->r_state = RT_CONSISTENT;
  634. _dl_debug_state();
  635. }
  636. char *_dl_getenv(const char *symbol, char **envp)
  637. {
  638. char *pnt;
  639. const char *pnt1;
  640. while ((pnt = *envp++)) {
  641. pnt1 = symbol;
  642. while (*pnt && *pnt == *pnt1)
  643. pnt1++, pnt++;
  644. if (!*pnt || *pnt != '=' || *pnt1)
  645. continue;
  646. return pnt + 1;
  647. }
  648. return 0;
  649. }
  650. void _dl_unsetenv(const char *symbol, char **envp)
  651. {
  652. char *pnt;
  653. const char *pnt1;
  654. char **newenvp = envp;
  655. for (pnt = *envp; pnt; pnt = *++envp) {
  656. pnt1 = symbol;
  657. while (*pnt && *pnt == *pnt1)
  658. pnt1++, pnt++;
  659. if (!*pnt || *pnt != '=' || *pnt1)
  660. *newenvp++ = *envp;
  661. }
  662. *newenvp++ = *envp;
  663. return;
  664. }
  665. static int _dl_suid_ok(void)
  666. {
  667. __kernel_uid_t uid, euid;
  668. __kernel_gid_t gid, egid;
  669. uid = _dl_getuid();
  670. euid = _dl_geteuid();
  671. gid = _dl_getgid();
  672. egid = _dl_getegid();
  673. if(uid == euid && gid == egid) {
  674. return 1;
  675. }
  676. return 0;
  677. }
  678. #include "dl-hash.c"
  679. #include "dl-elf.c"