1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 1991, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 /* 27 * Object file dependent support for a.out format objects. 28 */ 29 30 #include <a.out.h> /* Explicitly override M_SEGSIZE */ 31 #include <machdep.h> /* used in M_SROUND */ 32 33 #include <sys/types.h> 34 #include <sys/procfs.h> 35 #include <sys/mman.h> 36 #include <fcntl.h> 37 #include <unistd.h> 38 #include <string.h> 39 #include <limits.h> 40 #include <stdio.h> 41 #include <dlfcn.h> 42 #include <errno.h> 43 #include <debug.h> 44 #include "_a.out.h" 45 #include "cache_a.out.h" 46 #include "msg.h" 47 #include "_rtld.h" 48 49 /* 50 * Default and secure dependency search paths. 51 */ 52 static Spath_defn _aout_def_dirs[] = { 53 { MSG_ORIG(MSG_PTH_USR4LIB), MSG_PTH_USR4LIB_SIZE }, 54 { MSG_ORIG(MSG_PTH_USRLIB), MSG_PTH_USRLIB_SIZE }, 55 { MSG_ORIG(MSG_PTH_USRLCLIB), MSG_PTH_USRLCLIB_SIZE }, 56 { 0, 0 } 57 }; 58 59 static Spath_defn _aout_sec_dirs[] = { 60 { MSG_ORIG(MSG_PTH_LIBSE), MSG_PTH_LIBSE_SIZE }, 61 { 0, 0 } 62 }; 63 64 Alist *aout_def_dirs = NULL; 65 Alist *aout_sec_dirs = NULL; 66 67 /* 68 * Defines for local functions. 69 */ 70 static void aout_dladdr(ulong_t, Rt_map *, Dl_info *, void **, int); 71 static int aout_dlsym_handle(Grp_hdl *, Slookup *, Sresult *, uint_t *, 72 int *); 73 static Addr aout_entry_point(void); 74 static int aout_find_sym(Slookup *, Sresult *, uint_t *, int *); 75 static int aout_fix_name(const char *, Rt_map *, Alist **, Aliste, uint_t); 76 static Alist **aout_get_def_dirs(void); 77 static Alist **aout_get_sec_dirs(void); 78 static char *aout_get_so(const char *, const char *, size_t, size_t); 79 static int aout_needed(Lm_list *, Aliste, Rt_map *, int *); 80 81 /* 82 * Functions and data accessed through indirect pointers. 83 */ 84 Fct aout_fct = { 85 aout_verify, 86 aout_new_lmp, 87 aout_entry_point, 88 aout_needed, 89 aout_lookup_sym, 90 aout_reloc, 91 aout_get_def_dirs, 92 aout_get_sec_dirs, 93 aout_fix_name, 94 aout_get_so, 95 aout_dladdr, 96 aout_dlsym_handle 97 }; 98 99 /* 100 * Default and secure dependency search paths. 101 */ 102 static Alist ** 103 aout_get_def_dirs() 104 { 105 if (aout_def_dirs == NULL) 106 set_dirs(&aout_def_dirs, _aout_def_dirs, LA_SER_DEFAULT); 107 return (&aout_def_dirs); 108 } 109 110 static Alist ** 111 aout_get_sec_dirs() 112 { 113 if (aout_sec_dirs == NULL) 114 set_dirs(&aout_sec_dirs, _aout_sec_dirs, LA_SER_SECURE); 115 return (&aout_sec_dirs); 116 } 117 118 /* 119 * In 4.x, a needed file or a dlopened file that was a simple file name implied 120 * that the file be found in the present working directory. To simulate this 121 * lookup within the ELF rules it is necessary to add a preceding `./' to the 122 * filename. 123 */ 124 /* ARGSUSED4 */ 125 static int 126 aout_fix_name(const char *oname, Rt_map *clmp, Alist **alpp, Aliste alni, 127 uint_t orig) 128 { 129 size_t len; 130 Pdesc *pdp; 131 const char *nname; 132 133 /* 134 * Check for slash in name, if none, prepend "./", otherwise just 135 * return name given. 136 */ 137 if (strchr(oname, '/')) { 138 len = strlen(oname) + 1; 139 if ((nname = stravl_insert(oname, 0, len, 0)) == NULL) 140 return (0); 141 } else { 142 char buffer[PATH_MAX]; 143 144 len = strlen(oname) + 3; 145 (void) snprintf(buffer, len, MSG_ORIG(MSG_FMT_4XPATH), oname); 146 if ((nname = stravl_insert(buffer, 0, len, 0)) == NULL) 147 return (0); 148 } 149 150 if ((pdp = alist_append(alpp, NULL, sizeof (Pdesc), alni)) == NULL) 151 return (0); 152 153 pdp->pd_pname = nname; 154 pdp->pd_plen = len; 155 pdp->pd_flags = PD_FLG_PNSLASH; 156 157 DBG_CALL(Dbg_file_fixname(LIST(clmp), nname, oname)); 158 return (1); 159 } 160 161 /* 162 * Determine if we have been given an A_OUT file. Returns 1 if true. 163 */ 164 Fct * 165 /* ARGSUSED1 */ 166 aout_verify(caddr_t addr, size_t size, Fdesc *fdp, const char *name, 167 Rej_desc *rej) 168 { 169 /* LINTED */ 170 struct exec *exec = (struct exec *)addr; 171 172 if (size < sizeof (exec) || (exec->a_machtype != M_SPARC) || 173 (N_BADMAG(*exec))) { 174 return (NULL); 175 } 176 return (&aout_fct); 177 } 178 179 /* 180 * Return the entry point of the A_OUT executable. Although the entry point 181 * within an ELF file is flexible, the entry point of an A_OUT executable is 182 * always zero. 183 */ 184 static Addr 185 aout_entry_point() 186 { 187 return (0); 188 } 189 190 /* 191 * Search through the dynamic section for DT_NEEDED entries and perform one 192 * of two functions. If only the first argument is specified then load the 193 * defined shared object, otherwise add the link map representing the 194 * defined link map the the dlopen list. 195 */ 196 static int 197 aout_needed(Lm_list *lml, Aliste lmco, Rt_map *clmp, int *in_nfavl) 198 { 199 Alist *palp = NULL; 200 void *need; 201 202 for (need = &TEXTBASE(clmp)[AOUTDYN(clmp)->v2->ld_need]; 203 need != &TEXTBASE(clmp)[0]; 204 need = &TEXTBASE(clmp)[((Lnk_obj *)(need))->lo_next]) { 205 Rt_map *nlmp; 206 char *name; 207 208 name = &TEXTBASE(clmp)[((Lnk_obj *)(need))->lo_name]; 209 210 if (((Lnk_obj *)(need))->lo_library) { 211 /* 212 * If lo_library field is not NULL then this needed 213 * library was linked in using the "-l" option. 214 * Thus we need to rebuild the library name before 215 * trying to load it. 216 */ 217 char *file; 218 size_t len; 219 220 /* 221 * Allocate name length plus 20 for full library name. 222 * lib.so.. = 7 + (2 * short) + NULL = 7 + 12 + 1 = 20 223 */ 224 len = strlen(name) + 20; 225 if ((file = malloc(len)) == NULL) 226 return (0); 227 (void) snprintf(file, len, MSG_ORIG(MSG_FMT_4XLIB), 228 name, ((Lnk_obj *)(need))->lo_major, 229 ((Lnk_obj *)(need))->lo_minor); 230 231 DBG_CALL(Dbg_libs_find(lml, file)); 232 233 /* 234 * We need to determine what filename will match the 235 * the filename specified (ie, a libc.so.1.2 may match 236 * to a libc.so.1.3). It's the real pathname that is 237 * recorded in the link maps. If we are presently 238 * being traced, skip this pathname generation so 239 * that we fall through into load_so() to print the 240 * appropriate diagnostics. I don't like this at all. 241 */ 242 if (lml->lm_flags & LML_FLG_TRC_ENABLE) 243 name = file; 244 else { 245 Spath_desc sd = { search_rules, NULL, 0 }; 246 Pdesc *pdp; 247 char *path = NULL; 248 249 for (pdp = get_next_dir(&sd, clmp, 0); pdp; 250 pdp = get_next_dir(&sd, clmp, 0)) { 251 if (pdp->pd_pname == NULL) 252 continue; 253 254 if (path = aout_get_so(pdp->pd_pname, 255 file, 0, 0)) 256 break; 257 } 258 if (path == NULL) { 259 eprintf(lml, ERR_FATAL, 260 MSG_INTL(MSG_SYS_OPEN), file, 261 strerror(ENOENT)); 262 return (0); 263 } 264 name = path; 265 } 266 if (expand_paths(clmp, name, &palp, 267 AL_CNT_NEEDED, 0, 0) == 0) 268 return (0); 269 } else { 270 /* 271 * If the library is specified as a pathname, see if 272 * it must be fixed to specify the current working 273 * directory (ie. libc.so.1.2 -> ./libc.so.1.2). 274 */ 275 if (aout_fix_name(name, clmp, &palp, 276 AL_CNT_NEEDED, 0) == 0) 277 return (0); 278 } 279 280 DBG_CALL(Dbg_file_needed(clmp, name)); 281 282 nlmp = load_one(lml, lmco, palp, clmp, MODE(clmp), 0, 0, 283 in_nfavl); 284 remove_alist(&palp, 1); 285 if (((nlmp == NULL) || 286 (bind_one(clmp, nlmp, BND_NEEDED) == 0)) && 287 ((lml->lm_flags & LML_FLG_TRC_ENABLE) == 0)) 288 return (0); 289 } 290 291 return (1); 292 } 293 294 static Sym * 295 aout_symconvert(struct nlist *sp) 296 { 297 static Sym sym; 298 299 sym.st_value = sp->n_value; 300 sym.st_size = 0; 301 sym.st_info = 0; 302 sym.st_other = 0; 303 switch (sp->n_type) { 304 case N_EXT + N_ABS: 305 sym.st_shndx = SHN_ABS; 306 break; 307 case N_COMM: 308 sym.st_shndx = SHN_COMMON; 309 break; 310 case N_EXT + N_UNDF: 311 sym.st_shndx = SHN_UNDEF; 312 break; 313 default: 314 sym.st_shndx = 0; 315 break; 316 } 317 return (&sym); 318 } 319 320 /* 321 * Process a.out format commons. 322 */ 323 static struct nlist * 324 aout_find_com(struct nlist *sp, const char *name) 325 { 326 static struct rtc_symb *rtcp = NULL; 327 struct rtc_symb *rs, *trs; 328 const char *sl; 329 char *cp; 330 331 /* 332 * See if common is already allocated. 333 */ 334 trs = rtcp; 335 while (trs) { 336 sl = name; 337 cp = trs->rtc_sp->n_un.n_name; 338 while (*sl == *cp++) 339 if (*sl++ == '\0') 340 return (trs->rtc_sp); 341 trs = trs->rtc_next; 342 } 343 344 /* 345 * If we got here, common is not already allocated so allocate it. 346 */ 347 if ((rs = malloc(sizeof (struct rtc_symb))) == NULL) 348 return (NULL); 349 if ((rs->rtc_sp = malloc(sizeof (struct nlist))) == NULL) 350 return (NULL); 351 trs = rtcp; 352 rtcp = rs; 353 rs->rtc_next = trs; 354 *(rs->rtc_sp) = *sp; 355 if ((rs->rtc_sp->n_un.n_name = malloc(strlen(name) + 1)) == NULL) 356 return (NULL); 357 (void) strcpy(rs->rtc_sp->n_un.n_name, name); 358 rs->rtc_sp->n_type = N_COMM; 359 if ((rs->rtc_sp->n_value = 360 (long)calloc(rs->rtc_sp->n_value, 1)) == NULL) 361 return (NULL); 362 return (rs->rtc_sp); 363 } 364 365 /* 366 * Find a.out format symbol in the specified link map. Unlike the sister 367 * elf routine we re-calculate the symbols hash value for each link map 368 * we're looking at. 369 */ 370 static struct nlist * 371 aout_findsb(const char *aname, Rt_map *lmp, int flag) 372 { 373 const char *name = aname; 374 char *cp; 375 struct fshash *p; 376 int i; 377 struct nlist *sp; 378 ulong_t hval = 0; 379 380 #define HASHMASK 0x7fffffff 381 #define RTHS 126 382 383 /* 384 * The name passed to us is in ELF format, thus it is necessary to 385 * map this back to the A_OUT format to compute the hash value (see 386 * mapping rules in aout_lookup_sym()). Basically the symbols are 387 * mapped according to whether a leading `.' exists. 388 * 389 * elf symbol a.out symbol 390 * i. .bar -> .bar (LKUP_LDOT) 391 * ii. .nuts -> nuts 392 * iii. foo -> _foo 393 */ 394 if (*name == '.') { 395 if (!(flag & LKUP_LDOT)) 396 name++; 397 } else 398 hval = '_'; 399 400 while (*name) 401 hval = (hval << 1) + *name++; 402 hval = hval & HASHMASK; 403 404 i = hval % (AOUTDYN(lmp)->v2->ld_buckets == 0 ? RTHS : 405 AOUTDYN(lmp)->v2->ld_buckets); 406 p = LM2LP(lmp)->lp_hash + i; 407 408 if (p->fssymbno != -1) { 409 do { 410 sp = &LM2LP(lmp)->lp_symtab[p->fssymbno]; 411 cp = &LM2LP(lmp)->lp_symstr[sp->n_un.n_strx]; 412 name = aname; 413 if (*name == '.') { 414 if (!(flag & LKUP_LDOT)) 415 name++; 416 } else { 417 cp++; 418 } 419 while (*name == *cp++) { 420 if (*name++ == '\0') 421 return (sp); /* found */ 422 } 423 if (p->next == NULL) 424 return (NULL); /* not found */ 425 else 426 continue; 427 } while ((p = &LM2LP(lmp)->lp_hash[p->next]) != NULL); 428 } 429 return (NULL); 430 } 431 432 /* 433 * The symbol name we have been asked to look up is in A_OUT format, this 434 * symbol is mapped to the appropriate ELF format which is the standard by 435 * which symbols are passed around ld.so.1. The symbols are mapped 436 * according to whether a leading `_' or `.' exists. 437 * 438 * a.out symbol elf symbol 439 * i. _foo -> foo 440 * ii. .bar -> .bar (LKUP_LDOT) 441 * iii. nuts -> .nuts 442 */ 443 int 444 aout_lookup_sym(Slookup *slp, Sresult *srp, uint_t *binfo, int *in_nfavl) 445 { 446 char name[PATH_MAX]; 447 Slookup sl = *slp; 448 449 DBG_CALL(Dbg_syms_lookup_aout(LIST(slp->sl_cmap), slp->sl_name)); 450 451 if (*sl.sl_name == '_') 452 ++sl.sl_name; 453 else if (*sl.sl_name == '.') 454 sl.sl_flags |= LKUP_LDOT; 455 else { 456 name[0] = '.'; 457 (void) strcpy(&name[1], sl.sl_name); 458 sl.sl_name = name; 459 } 460 461 /* 462 * Call the generic lookup routine to cycle through the specified 463 * link maps. 464 */ 465 return (lookup_sym(&sl, srp, binfo, in_nfavl)); 466 } 467 468 /* 469 * Symbol lookup for an a.out format module. 470 */ 471 /* ARGSUSED3 */ 472 static int 473 aout_find_sym(Slookup *slp, Sresult *srp, uint_t *binfo, int *in_nfavl) 474 { 475 const char *name = slp->sl_name; 476 Rt_map *ilmp = slp->sl_imap; 477 struct nlist *sp; 478 479 DBG_CALL(Dbg_syms_lookup(ilmp, name, MSG_ORIG(MSG_STR_AOUT))); 480 481 if (sp = aout_findsb(name, ilmp, slp->sl_flags)) { 482 if (sp->n_value != 0) { 483 /* 484 * is it a common? 485 */ 486 if (sp->n_type == (N_EXT + N_UNDF)) { 487 if ((sp = aout_find_com(sp, name)) == NULL) 488 return (0); 489 } 490 srp->sr_dmap = ilmp; 491 srp->sr_sym = aout_symconvert(sp); 492 *binfo |= DBG_BINFO_FOUND; 493 return (1); 494 } 495 } 496 return (0); 497 } 498 499 /* 500 * Create a new Rt_map structure for an a.out format object and 501 * initializes all values. 502 */ 503 /* ARGSUSED6 */ 504 Rt_map * 505 aout_new_lmp(Lm_list *lml, Aliste lmco, Fdesc *fdp, Addr addr, size_t msize, 506 void *odyn, Rt_map *clmp, int *in_nfavl) 507 { 508 const char *name = fdp->fd_nname; 509 Rt_map *lmp; 510 caddr_t base, caddr = (caddr_t)addr; 511 Link_dynamic *ld = (Link_dynamic *)odyn; 512 size_t lmsz, rtsz, prsz; 513 514 DBG_CALL(Dbg_file_aout(lml, name, addr, msize, lml->lm_lmidstr, lmco)); 515 516 /* 517 * Allocate space for the link-map and private a.out information. Once 518 * these are allocated and initialized, we can use remove_so(0, lmp) to 519 * tear down the link-map should any failures occur. 520 */ 521 rtsz = S_DROUND(sizeof (Rt_map)); 522 prsz = S_DROUND(sizeof (Rt_aoutp)); 523 lmsz = rtsz + prsz + sizeof (struct ld_private); 524 if ((lmp = calloc(lmsz, 1)) == NULL) 525 return (NULL); 526 AOUTPRV(lmp) = (void *)((uintptr_t)lmp + rtsz); 527 ((Rt_aoutp *)AOUTPRV(lmp))->lm_lpd = 528 (void *)((uintptr_t)lmp + rtsz + prsz); 529 LMSIZE(lmp) = lmsz; 530 531 /* 532 * All fields not filled in were set to 0 by calloc. 533 */ 534 NAME(lmp) = (char *)name; 535 ADDR(lmp) = addr; 536 MSIZE(lmp) = msize; 537 SYMINTP(lmp) = aout_find_sym; 538 FCT(lmp) = &aout_fct; 539 LIST(lmp) = lml; 540 OBJFLTRNDX(lmp) = FLTR_DISABLED; 541 SORTVAL(lmp) = -1; 542 543 /* 544 * Specific settings for a.out format. 545 */ 546 if (lml->lm_head == NULL) { 547 base = (caddr_t)MAIN_BASE; 548 FLAGS(lmp) |= FLG_RT_FIXED; 549 } else 550 base = caddr; 551 552 /* 553 * Fill in all AOUT information. Applications provide the Link_dynamic 554 * offset via the boot block, but if this is a shared object that 555 * ld.so.1 has mapped, then determine the Link_dynamic offset from the 556 * mapped image. 557 */ 558 if (ld == NULL) { 559 /* LINTED */ 560 struct exec *exec = (struct exec *)caddr; 561 struct nlist *nl; 562 563 /* LINTED */ 564 nl = (struct nlist *)&caddr[N_SYMOFF(*exec)]; 565 /* LINTED */ 566 ld = (Link_dynamic *)&caddr[nl->n_value]; 567 568 ld->v2 = (struct link_dynamic_2 *)((int)ld->v2 + (int)caddr); 569 } 570 AOUTDYN(lmp) = ld; 571 572 if ((RPATH(lmp) = (char *)&base[ld->v2->ld_rules]) == base) 573 RPATH(lmp) = NULL; 574 LM2LP(lmp)->lp_symbol_base = caddr; 575 /* LINTED */ 576 LM2LP(lmp)->lp_plt = (struct jbind *)(&caddr[JMPOFF(ld)]); 577 LM2LP(lmp)->lp_rp = 578 /* LINTED */ 579 (struct relocation_info *)(&base[RELOCOFF(ld)]); 580 /* LINTED */ 581 LM2LP(lmp)->lp_hash = (struct fshash *)(&base[HASHOFF(ld)]); 582 /* LINTED */ 583 LM2LP(lmp)->lp_symtab = (struct nlist *)(&base[SYMOFF(ld)]); 584 LM2LP(lmp)->lp_symstr = &base[STROFF(ld)]; 585 LM2LP(lmp)->lp_textbase = base; 586 LM2LP(lmp)->lp_refcnt++; 587 LM2LP(lmp)->lp_dlp = NULL; 588 589 /* 590 * Add the mapped object to the end of the link map list. 591 */ 592 lm_append(lml, lmco, lmp); 593 return (lmp); 594 } 595 596 /* 597 * Build full pathname of shared object from the given directory name and 598 * filename. 599 */ 600 static char * 601 /* ARGSUSED2 */ 602 aout_get_so(const char *dir, const char *file, size_t dlen, size_t flen) 603 { 604 struct db *dbp; 605 char *path = NULL; 606 607 if (dbp = lo_cache(dir)) { 608 path = ask_db(dbp, file); 609 } 610 return (path); 611 } 612 613 /* 614 * Determine the symbol location of an address within a link-map. Look for 615 * the nearest symbol (whoes value is less than or equal to the required 616 * address). This is the object specific part of dladdr(). 617 */ 618 static void 619 aout_dladdr(ulong_t addr, Rt_map *lmp, Dl_info *dlip, void **info, 620 int flags) 621 { 622 ulong_t ndx, cnt, base, _value; 623 struct nlist *sym, *_sym; 624 625 cnt = ((int)LM2LP(lmp)->lp_symstr - (int)LM2LP(lmp)->lp_symtab) / 626 sizeof (struct nlist); 627 sym = LM2LP(lmp)->lp_symtab; 628 629 if (FLAGS(lmp) & FLG_RT_FIXED) 630 base = 0; 631 else 632 base = ADDR(lmp); 633 634 for (_sym = NULL, _value = 0, ndx = 0; ndx < cnt; ndx++, sym++) { 635 ulong_t value; 636 637 if (sym->n_type == (N_EXT + N_UNDF)) 638 continue; 639 640 value = sym->n_value + base; 641 if (value > addr) 642 continue; 643 if (value < _value) 644 continue; 645 646 _sym = sym; 647 _value = value; 648 649 if (value == addr) 650 break; 651 } 652 653 if (_sym) { 654 int _flags = flags & RTLD_DL_MASK; 655 656 /* 657 * The only way we can create a symbol entry is to use 658 * aout_symconvert(), however this results in us pointing to 659 * static data that could be overridden. In addition the AOUT 660 * symbol format doesn't give us everything an ELF symbol does. 661 * So, unless we get convinced otherwise, don't bother returning 662 * a symbol entry for AOUT's. 663 */ 664 if (_flags == RTLD_DL_SYMENT) 665 *info = NULL; 666 else if (_flags == RTLD_DL_LINKMAP) 667 *info = (void *)lmp; 668 669 dlip->dli_sname = &LM2LP(lmp)->lp_symstr[_sym->n_un.n_strx]; 670 dlip->dli_saddr = (void *)_value; 671 } 672 } 673 674 /* 675 * Continue processing a dlsym request. Lookup the required symbol in each 676 * link-map specified by the handle. Note, that because this lookup is against 677 * individual link-maps we don't need to supply a starting link-map to the 678 * lookup routine (see lookup_sym():analyze.c). 679 */ 680 static int 681 aout_dlsym_handle(Grp_hdl *ghp, Slookup *slp, Sresult *srp, uint_t *binfo, 682 int *in_nfavl) 683 { 684 char buffer[PATH_MAX]; 685 Slookup sl; 686 687 if (dlsym_handle(ghp, slp, srp, binfo, in_nfavl)) 688 return (1); 689 690 /* 691 * Symbol not found as supplied. However, most of our symbols will 692 * be in the "C" name space, where the implementation prepends a "_" 693 * to the symbol as it emits it. Therefore, attempt to find the 694 * symbol with the "_" prepend. 695 */ 696 buffer[0] = '_'; 697 (void) strcpy(&buffer[1], slp->sl_name); 698 699 sl = *slp; 700 sl.sl_name = (const char *)buffer; 701 702 return (dlsym_handle(ghp, &sl, srp, binfo, in_nfavl)); 703 } 704 705 /* 706 * The initial mapping of the a.out occurs through exec(2), and presently this 707 * implementation doesn't provide a mmapobj_result_t array to ld.so.1. Thus, 708 * aout_get_mmap() is called to create the mapping information. Unlike ELF, 709 * the information that can be gathered from a mapped AOUT file, can be limited. 710 * In some cases the AOUT header isn't available in the mapped image, and thus 711 * this can't be inspected to determine the files size (the kernel always 712 * returns a pointer to the AOUT dynamic structure, but this is only sufficient 713 * to determine the size of the text segment). 714 * 715 * Therefore, the only generic mechanism of determining the AOUT's mapping is 716 * to use /proc. Only two mappings are required, the text (to determine any 717 * read-only region), and the data. The two mapping validate the range in 718 * which any relocations will occur. Should there be an additional bss segment, 719 * we don't care, as this can't be relocated, and we're never going to try 720 * unmapping the a.out. 721 */ 722 #define PROCSIZE 20 723 724 int 725 aout_get_mmap(Lm_list *lml, mmapobj_result_t *mpp) 726 { 727 prmap_t *maps; 728 char proc[PROCSIZE]; 729 int num, err, fd; 730 731 (void) snprintf(proc, PROCSIZE, MSG_ORIG(MSG_FMT_PROC), 732 EC_SWORD(getpid())); 733 if ((fd = open(proc, O_RDONLY)) == -1) { 734 err = errno; 735 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_OPEN), proc, 736 strerror(err)); 737 return (1); 738 } 739 740 if (ioctl(fd, PIOCNMAP, (void *)&num) == -1) { 741 err = errno; 742 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), strerror(err)); 743 return (1); 744 } 745 746 if ((maps = malloc((num + 1) * sizeof (prmap_t))) == NULL) 747 return (1); 748 749 if (ioctl(fd, PIOCMAP, (void *)maps) == -1) { 750 err = errno; 751 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_PROC), strerror(err)); 752 free(maps); 753 return (1); 754 } 755 756 mpp->mr_addr = maps->pr_vaddr; 757 mpp->mr_fsize = mpp->mr_msize = maps->pr_size; 758 mpp->mr_prot = (PROT_READ | PROT_EXEC); 759 760 mpp++, maps++; 761 762 mpp->mr_addr = maps->pr_vaddr; 763 mpp->mr_fsize = mpp->mr_msize = maps->pr_size; 764 mpp->mr_prot = (PROT_READ | PROT_WRITE | PROT_EXEC); 765 766 maps--; 767 free(maps); 768 return (0); 769 } 770