1 /*- 2 * Copyright (c) 1997-2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_ddb.h" 31 #include "opt_hwpmc_hooks.h" 32 #include "opt_mac.h" 33 34 #include <sys/param.h> 35 #include <sys/kernel.h> 36 #include <sys/systm.h> 37 #include <sys/malloc.h> 38 #include <sys/sysproto.h> 39 #include <sys/sysent.h> 40 #include <sys/priv.h> 41 #include <sys/proc.h> 42 #include <sys/lock.h> 43 #include <sys/mutex.h> 44 #include <sys/sx.h> 45 #include <sys/module.h> 46 #include <sys/mount.h> 47 #include <sys/linker.h> 48 #include <sys/fcntl.h> 49 #include <sys/libkern.h> 50 #include <sys/namei.h> 51 #include <sys/vnode.h> 52 #include <sys/syscallsubr.h> 53 #include <sys/sysctl.h> 54 55 #include <security/mac/mac_framework.h> 56 57 #include "linker_if.h" 58 59 #ifdef HWPMC_HOOKS 60 #include <sys/pmckern.h> 61 #endif 62 63 #ifdef KLD_DEBUG 64 int kld_debug = 0; 65 #endif 66 67 #define KLD_LOCK() sx_xlock(&kld_sx) 68 #define KLD_UNLOCK() sx_xunlock(&kld_sx) 69 #define KLD_LOCKED() sx_xlocked(&kld_sx) 70 #define KLD_LOCK_ASSERT() do { \ 71 if (!cold) \ 72 sx_assert(&kld_sx, SX_XLOCKED); \ 73 } while (0) 74 75 /* 76 * static char *linker_search_path(const char *name, struct mod_depend 77 * *verinfo); 78 */ 79 static const char *linker_basename(const char *path); 80 81 /* 82 * Find a currently loaded file given its filename. 83 */ 84 static linker_file_t linker_find_file_by_name(const char* _filename); 85 86 /* 87 * Find a currently loaded file given its file id. 88 */ 89 static linker_file_t linker_find_file_by_id(int _fileid); 90 91 /* Metadata from the static kernel */ 92 SET_DECLARE(modmetadata_set, struct mod_metadata); 93 94 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 95 96 linker_file_t linker_kernel_file; 97 98 static struct sx kld_sx; /* kernel linker lock */ 99 100 /* 101 * Load counter used by clients to determine if a linker file has been 102 * re-loaded. This counter is incremented for each file load. 103 */ 104 static int loadcnt; 105 106 static linker_class_list_t classes; 107 static linker_file_list_t linker_files; 108 static int next_file_id = 1; 109 static int linker_no_more_classes = 0; 110 111 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 112 linker_file_t lftmp; \ 113 \ 114 KLD_LOCK_ASSERT(); \ 115 retry: \ 116 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 117 if (next_file_id == lftmp->id) { \ 118 next_file_id++; \ 119 goto retry; \ 120 } \ 121 } \ 122 (a) = next_file_id; \ 123 } while(0) 124 125 126 /* XXX wrong name; we're looking at version provision tags here, not modules */ 127 typedef TAILQ_HEAD(, modlist) modlisthead_t; 128 struct modlist { 129 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 130 linker_file_t container; 131 const char *name; 132 int version; 133 }; 134 typedef struct modlist *modlist_t; 135 static modlisthead_t found_modules; 136 137 static int linker_file_add_dependency(linker_file_t file, 138 linker_file_t dep); 139 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file, 140 const char* name, int deps); 141 static int linker_load_module(const char *kldname, 142 const char *modname, struct linker_file *parent, 143 struct mod_depend *verinfo, struct linker_file **lfpp); 144 static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo); 145 146 static char * 147 linker_strdup(const char *str) 148 { 149 char *result; 150 151 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 152 strcpy(result, str); 153 return (result); 154 } 155 156 static void 157 linker_init(void *arg) 158 { 159 160 sx_init(&kld_sx, "kernel linker"); 161 TAILQ_INIT(&classes); 162 TAILQ_INIT(&linker_files); 163 } 164 165 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 166 167 static void 168 linker_stop_class_add(void *arg) 169 { 170 171 linker_no_more_classes = 1; 172 } 173 174 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 175 176 int 177 linker_add_class(linker_class_t lc) 178 { 179 180 /* 181 * We disallow any class registration past SI_ORDER_ANY 182 * of SI_SUB_KLD. We bump the reference count to keep the 183 * ops from being freed. 184 */ 185 if (linker_no_more_classes == 1) 186 return (EPERM); 187 kobj_class_compile((kobj_class_t) lc); 188 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 189 TAILQ_INSERT_TAIL(&classes, lc, link); 190 return (0); 191 } 192 193 static void 194 linker_file_sysinit(linker_file_t lf) 195 { 196 struct sysinit **start, **stop, **sipp, **xipp, *save; 197 198 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 199 lf->filename)); 200 201 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 202 return; 203 /* 204 * Perform a bubble sort of the system initialization objects by 205 * their subsystem (primary key) and order (secondary key). 206 * 207 * Since some things care about execution order, this is the operation 208 * which ensures continued function. 209 */ 210 for (sipp = start; sipp < stop; sipp++) { 211 for (xipp = sipp + 1; xipp < stop; xipp++) { 212 if ((*sipp)->subsystem < (*xipp)->subsystem || 213 ((*sipp)->subsystem == (*xipp)->subsystem && 214 (*sipp)->order <= (*xipp)->order)) 215 continue; /* skip */ 216 save = *sipp; 217 *sipp = *xipp; 218 *xipp = save; 219 } 220 } 221 222 /* 223 * Traverse the (now) ordered list of system initialization tasks. 224 * Perform each task, and continue on to the next task. 225 */ 226 mtx_lock(&Giant); 227 for (sipp = start; sipp < stop; sipp++) { 228 if ((*sipp)->subsystem == SI_SUB_DUMMY) 229 continue; /* skip dummy task(s) */ 230 231 /* Call function */ 232 (*((*sipp)->func)) ((*sipp)->udata); 233 } 234 mtx_unlock(&Giant); 235 } 236 237 static void 238 linker_file_sysuninit(linker_file_t lf) 239 { 240 struct sysinit **start, **stop, **sipp, **xipp, *save; 241 242 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 243 lf->filename)); 244 245 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 246 NULL) != 0) 247 return; 248 249 /* 250 * Perform a reverse bubble sort of the system initialization objects 251 * by their subsystem (primary key) and order (secondary key). 252 * 253 * Since some things care about execution order, this is the operation 254 * which ensures continued function. 255 */ 256 for (sipp = start; sipp < stop; sipp++) { 257 for (xipp = sipp + 1; xipp < stop; xipp++) { 258 if ((*sipp)->subsystem > (*xipp)->subsystem || 259 ((*sipp)->subsystem == (*xipp)->subsystem && 260 (*sipp)->order >= (*xipp)->order)) 261 continue; /* skip */ 262 save = *sipp; 263 *sipp = *xipp; 264 *xipp = save; 265 } 266 } 267 268 /* 269 * Traverse the (now) ordered list of system initialization tasks. 270 * Perform each task, and continue on to the next task. 271 */ 272 mtx_lock(&Giant); 273 for (sipp = start; sipp < stop; sipp++) { 274 if ((*sipp)->subsystem == SI_SUB_DUMMY) 275 continue; /* skip dummy task(s) */ 276 277 /* Call function */ 278 (*((*sipp)->func)) ((*sipp)->udata); 279 } 280 mtx_unlock(&Giant); 281 } 282 283 static void 284 linker_file_register_sysctls(linker_file_t lf) 285 { 286 struct sysctl_oid **start, **stop, **oidp; 287 288 KLD_DPF(FILE, 289 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 290 lf->filename)); 291 292 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 293 return; 294 295 mtx_lock(&Giant); 296 for (oidp = start; oidp < stop; oidp++) 297 sysctl_register_oid(*oidp); 298 mtx_unlock(&Giant); 299 } 300 301 static void 302 linker_file_unregister_sysctls(linker_file_t lf) 303 { 304 struct sysctl_oid **start, **stop, **oidp; 305 306 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 307 " for %s\n", lf->filename)); 308 309 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 310 return; 311 312 mtx_lock(&Giant); 313 for (oidp = start; oidp < stop; oidp++) 314 sysctl_unregister_oid(*oidp); 315 mtx_unlock(&Giant); 316 } 317 318 static int 319 linker_file_register_modules(linker_file_t lf) 320 { 321 struct mod_metadata **start, **stop, **mdp; 322 const moduledata_t *moddata; 323 int first_error, error; 324 325 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 326 " in %s\n", lf->filename)); 327 328 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 329 &stop, NULL) != 0) { 330 /* 331 * This fallback should be unnecessary, but if we get booted 332 * from boot2 instead of loader and we are missing our 333 * metadata then we have to try the best we can. 334 */ 335 if (lf == linker_kernel_file) { 336 start = SET_BEGIN(modmetadata_set); 337 stop = SET_LIMIT(modmetadata_set); 338 } else 339 return (0); 340 } 341 first_error = 0; 342 for (mdp = start; mdp < stop; mdp++) { 343 if ((*mdp)->md_type != MDT_MODULE) 344 continue; 345 moddata = (*mdp)->md_data; 346 KLD_DPF(FILE, ("Registering module %s in %s\n", 347 moddata->name, lf->filename)); 348 error = module_register(moddata, lf); 349 if (error) { 350 printf("Module %s failed to register: %d\n", 351 moddata->name, error); 352 if (first_error == 0) 353 first_error = error; 354 } 355 } 356 return (first_error); 357 } 358 359 static void 360 linker_init_kernel_modules(void) 361 { 362 363 linker_file_register_modules(linker_kernel_file); 364 } 365 366 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 367 368 static int 369 linker_load_file(const char *filename, linker_file_t *result) 370 { 371 linker_class_t lc; 372 linker_file_t lf; 373 int foundfile, error; 374 375 /* Refuse to load modules if securelevel raised */ 376 if (securelevel > 0) 377 return (EPERM); 378 379 KLD_LOCK_ASSERT(); 380 lf = linker_find_file_by_name(filename); 381 if (lf) { 382 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 383 " incrementing refs\n", filename)); 384 *result = lf; 385 lf->refs++; 386 return (0); 387 } 388 foundfile = 0; 389 error = 0; 390 391 /* 392 * We do not need to protect (lock) classes here because there is 393 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 394 * and there is no class deregistration mechanism at this time. 395 */ 396 TAILQ_FOREACH(lc, &classes, link) { 397 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 398 filename)); 399 error = LINKER_LOAD_FILE(lc, filename, &lf); 400 /* 401 * If we got something other than ENOENT, then it exists but 402 * we cannot load it for some other reason. 403 */ 404 if (error != ENOENT) 405 foundfile = 1; 406 if (lf) { 407 error = linker_file_register_modules(lf); 408 if (error == EEXIST) { 409 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 410 return (error); 411 } 412 KLD_UNLOCK(); 413 linker_file_register_sysctls(lf); 414 linker_file_sysinit(lf); 415 KLD_LOCK(); 416 lf->flags |= LINKER_FILE_LINKED; 417 *result = lf; 418 return (0); 419 } 420 } 421 /* 422 * Less than ideal, but tells the user whether it failed to load or 423 * the module was not found. 424 */ 425 if (foundfile) { 426 /* 427 * Format not recognized or otherwise unloadable. 428 * When loading a module that is statically built into 429 * the kernel EEXIST percolates back up as the return 430 * value. Preserve this so that apps like sysinstall 431 * can recognize this special case and not post bogus 432 * dialog boxes. 433 */ 434 if (error != EEXIST) 435 error = ENOEXEC; 436 } else 437 error = ENOENT; /* Nothing found */ 438 return (error); 439 } 440 441 int 442 linker_reference_module(const char *modname, struct mod_depend *verinfo, 443 linker_file_t *result) 444 { 445 modlist_t mod; 446 int error; 447 448 KLD_LOCK(); 449 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 450 *result = mod->container; 451 (*result)->refs++; 452 KLD_UNLOCK(); 453 return (0); 454 } 455 456 error = linker_load_module(NULL, modname, NULL, verinfo, result); 457 KLD_UNLOCK(); 458 return (error); 459 } 460 461 int 462 linker_release_module(const char *modname, struct mod_depend *verinfo, 463 linker_file_t lf) 464 { 465 modlist_t mod; 466 int error; 467 468 KLD_LOCK(); 469 if (lf == NULL) { 470 KASSERT(modname != NULL, 471 ("linker_release_module: no file or name")); 472 mod = modlist_lookup2(modname, verinfo); 473 if (mod == NULL) { 474 KLD_UNLOCK(); 475 return (ESRCH); 476 } 477 lf = mod->container; 478 } else 479 KASSERT(modname == NULL && verinfo == NULL, 480 ("linker_release_module: both file and name")); 481 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 482 KLD_UNLOCK(); 483 return (error); 484 } 485 486 static linker_file_t 487 linker_find_file_by_name(const char *filename) 488 { 489 linker_file_t lf; 490 char *koname; 491 492 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 493 sprintf(koname, "%s.ko", filename); 494 495 KLD_LOCK_ASSERT(); 496 TAILQ_FOREACH(lf, &linker_files, link) { 497 if (strcmp(lf->filename, koname) == 0) 498 break; 499 if (strcmp(lf->filename, filename) == 0) 500 break; 501 } 502 free(koname, M_LINKER); 503 return (lf); 504 } 505 506 static linker_file_t 507 linker_find_file_by_id(int fileid) 508 { 509 linker_file_t lf; 510 511 KLD_LOCK_ASSERT(); 512 TAILQ_FOREACH(lf, &linker_files, link) 513 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 514 break; 515 return (lf); 516 } 517 518 int 519 linker_file_foreach(linker_predicate_t *predicate, void *context) 520 { 521 linker_file_t lf; 522 int retval = 0; 523 524 KLD_LOCK(); 525 TAILQ_FOREACH(lf, &linker_files, link) { 526 retval = predicate(lf, context); 527 if (retval != 0) 528 break; 529 } 530 KLD_UNLOCK(); 531 return (retval); 532 } 533 534 linker_file_t 535 linker_make_file(const char *pathname, linker_class_t lc) 536 { 537 linker_file_t lf; 538 const char *filename; 539 540 KLD_LOCK_ASSERT(); 541 filename = linker_basename(pathname); 542 543 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 544 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 545 if (lf == NULL) 546 return (NULL); 547 lf->refs = 1; 548 lf->userrefs = 0; 549 lf->flags = 0; 550 lf->filename = linker_strdup(filename); 551 lf->pathname = linker_strdup(pathname); 552 LINKER_GET_NEXT_FILE_ID(lf->id); 553 lf->ndeps = 0; 554 lf->deps = NULL; 555 lf->loadcnt = ++loadcnt; 556 lf->sdt_probes = NULL; 557 lf->sdt_nprobes = 0; 558 STAILQ_INIT(&lf->common); 559 TAILQ_INIT(&lf->modules); 560 TAILQ_INSERT_TAIL(&linker_files, lf, link); 561 return (lf); 562 } 563 564 int 565 linker_file_unload(linker_file_t file, int flags) 566 { 567 module_t mod, next; 568 modlist_t ml, nextml; 569 struct common_symbol *cp; 570 int error, i; 571 572 /* Refuse to unload modules if securelevel raised. */ 573 if (securelevel > 0) 574 return (EPERM); 575 576 KLD_LOCK_ASSERT(); 577 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 578 579 /* Easy case of just dropping a reference. */ 580 if (file->refs > 1) { 581 file->refs--; 582 return (0); 583 } 584 585 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 586 " informing modules\n")); 587 588 /* 589 * Inform any modules associated with this file. 590 */ 591 MOD_XLOCK; 592 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 593 next = module_getfnext(mod); 594 MOD_XUNLOCK; 595 596 /* 597 * Give the module a chance to veto the unload. 598 */ 599 if ((error = module_unload(mod, flags)) != 0) { 600 KLD_DPF(FILE, ("linker_file_unload: module %p" 601 " vetoes unload\n", mod)); 602 return (error); 603 } 604 MOD_XLOCK; 605 module_release(mod); 606 } 607 MOD_XUNLOCK; 608 609 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 610 if (ml->container == file) { 611 TAILQ_REMOVE(&found_modules, ml, link); 612 free(ml, M_LINKER); 613 } 614 } 615 616 /* 617 * Don't try to run SYSUNINITs if we are unloaded due to a 618 * link error. 619 */ 620 if (file->flags & LINKER_FILE_LINKED) { 621 linker_file_sysuninit(file); 622 linker_file_unregister_sysctls(file); 623 } 624 TAILQ_REMOVE(&linker_files, file, link); 625 626 if (file->deps) { 627 for (i = 0; i < file->ndeps; i++) 628 linker_file_unload(file->deps[i], flags); 629 free(file->deps, M_LINKER); 630 file->deps = NULL; 631 } 632 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 633 STAILQ_REMOVE_HEAD(&file->common, link); 634 free(cp, M_LINKER); 635 } 636 637 LINKER_UNLOAD(file); 638 if (file->filename) { 639 free(file->filename, M_LINKER); 640 file->filename = NULL; 641 } 642 if (file->pathname) { 643 free(file->pathname, M_LINKER); 644 file->pathname = NULL; 645 } 646 kobj_delete((kobj_t) file, M_LINKER); 647 return (0); 648 } 649 650 static int 651 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 652 { 653 linker_file_t *newdeps; 654 655 KLD_LOCK_ASSERT(); 656 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 657 M_LINKER, M_WAITOK | M_ZERO); 658 if (newdeps == NULL) 659 return (ENOMEM); 660 661 if (file->deps) { 662 bcopy(file->deps, newdeps, 663 file->ndeps * sizeof(linker_file_t *)); 664 free(file->deps, M_LINKER); 665 } 666 file->deps = newdeps; 667 file->deps[file->ndeps] = dep; 668 file->ndeps++; 669 return (0); 670 } 671 672 /* 673 * Locate a linker set and its contents. This is a helper function to avoid 674 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 675 * This function is used in this file so we can avoid having lots of (void **) 676 * casts. 677 */ 678 int 679 linker_file_lookup_set(linker_file_t file, const char *name, 680 void *firstp, void *lastp, int *countp) 681 { 682 int error, locked; 683 684 locked = KLD_LOCKED(); 685 if (!locked) 686 KLD_LOCK(); 687 error = LINKER_LOOKUP_SET(file, name, firstp, lastp, countp); 688 if (!locked) 689 KLD_UNLOCK(); 690 return (error); 691 } 692 693 caddr_t 694 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 695 { 696 caddr_t sym; 697 int locked; 698 699 locked = KLD_LOCKED(); 700 if (!locked) 701 KLD_LOCK(); 702 sym = linker_file_lookup_symbol_internal(file, name, deps); 703 if (!locked) 704 KLD_UNLOCK(); 705 return (sym); 706 } 707 708 static caddr_t 709 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 710 int deps) 711 { 712 c_linker_sym_t sym; 713 linker_symval_t symval; 714 caddr_t address; 715 size_t common_size = 0; 716 int i; 717 718 KLD_LOCK_ASSERT(); 719 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 720 file, name, deps)); 721 722 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 723 LINKER_SYMBOL_VALUES(file, sym, &symval); 724 if (symval.value == 0) 725 /* 726 * For commons, first look them up in the 727 * dependencies and only allocate space if not found 728 * there. 729 */ 730 common_size = symval.size; 731 else { 732 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 733 ".value=%p\n", symval.value)); 734 return (symval.value); 735 } 736 } 737 if (deps) { 738 for (i = 0; i < file->ndeps; i++) { 739 address = linker_file_lookup_symbol_internal( 740 file->deps[i], name, 0); 741 if (address) { 742 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 743 " deps value=%p\n", address)); 744 return (address); 745 } 746 } 747 } 748 if (common_size > 0) { 749 /* 750 * This is a common symbol which was not found in the 751 * dependencies. We maintain a simple common symbol table in 752 * the file object. 753 */ 754 struct common_symbol *cp; 755 756 STAILQ_FOREACH(cp, &file->common, link) { 757 if (strcmp(cp->name, name) == 0) { 758 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 759 " old common value=%p\n", cp->address)); 760 return (cp->address); 761 } 762 } 763 /* 764 * Round the symbol size up to align. 765 */ 766 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 767 cp = malloc(sizeof(struct common_symbol) 768 + common_size + strlen(name) + 1, M_LINKER, 769 M_WAITOK | M_ZERO); 770 cp->address = (caddr_t)(cp + 1); 771 cp->name = cp->address + common_size; 772 strcpy(cp->name, name); 773 bzero(cp->address, common_size); 774 STAILQ_INSERT_TAIL(&file->common, cp, link); 775 776 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 777 " value=%p\n", cp->address)); 778 return (cp->address); 779 } 780 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 781 return (0); 782 } 783 784 #ifdef DDB 785 /* 786 * DDB Helpers. DDB has to look across multiple files with their own symbol 787 * tables and string tables. 788 * 789 * Note that we do not obey list locking protocols here. We really don't need 790 * DDB to hang because somebody's got the lock held. We'll take the chance 791 * that the files list is inconsistant instead. 792 */ 793 794 int 795 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 796 { 797 linker_file_t lf; 798 799 TAILQ_FOREACH(lf, &linker_files, link) { 800 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 801 return (0); 802 } 803 return (ENOENT); 804 } 805 806 int 807 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 808 { 809 linker_file_t lf; 810 c_linker_sym_t best, es; 811 u_long diff, bestdiff, off; 812 813 best = 0; 814 off = (uintptr_t)value; 815 bestdiff = off; 816 TAILQ_FOREACH(lf, &linker_files, link) { 817 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 818 continue; 819 if (es != 0 && diff < bestdiff) { 820 best = es; 821 bestdiff = diff; 822 } 823 if (bestdiff == 0) 824 break; 825 } 826 if (best) { 827 *sym = best; 828 *diffp = bestdiff; 829 return (0); 830 } else { 831 *sym = 0; 832 *diffp = off; 833 return (ENOENT); 834 } 835 } 836 837 int 838 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 839 { 840 linker_file_t lf; 841 842 TAILQ_FOREACH(lf, &linker_files, link) { 843 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 844 return (0); 845 } 846 return (ENOENT); 847 } 848 #endif 849 850 /* 851 * Syscalls. 852 */ 853 int 854 kern_kldload(struct thread *td, const char *file, int *fileid) 855 { 856 #ifdef HWPMC_HOOKS 857 struct pmckern_map_in pkm; 858 #endif 859 const char *kldname, *modname; 860 linker_file_t lf; 861 int error; 862 863 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 864 return (error); 865 866 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 867 return (error); 868 869 /* 870 * If file does not contain a qualified name or any dot in it 871 * (kldname.ko, or kldname.ver.ko) treat it as an interface 872 * name. 873 */ 874 if (index(file, '/') || index(file, '.')) { 875 kldname = file; 876 modname = NULL; 877 } else { 878 kldname = NULL; 879 modname = file; 880 } 881 882 KLD_LOCK(); 883 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 884 if (error) 885 goto unlock; 886 #ifdef HWPMC_HOOKS 887 pkm.pm_file = lf->filename; 888 pkm.pm_address = (uintptr_t) lf->address; 889 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 890 #endif 891 lf->userrefs++; 892 if (fileid != NULL) 893 *fileid = lf->id; 894 unlock: 895 KLD_UNLOCK(); 896 return (error); 897 } 898 899 int 900 kldload(struct thread *td, struct kldload_args *uap) 901 { 902 char *pathname = NULL; 903 int error, fileid; 904 905 td->td_retval[0] = -1; 906 907 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 908 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 909 if (error == 0) { 910 error = kern_kldload(td, pathname, &fileid); 911 if (error == 0) 912 td->td_retval[0] = fileid; 913 } 914 free(pathname, M_TEMP); 915 return (error); 916 } 917 918 int 919 kern_kldunload(struct thread *td, int fileid, int flags) 920 { 921 #ifdef HWPMC_HOOKS 922 struct pmckern_map_out pkm; 923 #endif 924 linker_file_t lf; 925 int error = 0; 926 927 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 928 return (error); 929 930 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 931 return (error); 932 933 KLD_LOCK(); 934 lf = linker_find_file_by_id(fileid); 935 if (lf) { 936 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 937 938 /* Check if there are DTrace probes enabled on this file. */ 939 if (lf->nenabled > 0) { 940 printf("kldunload: attempt to unload file that has" 941 " DTrace probes enabled\n"); 942 error = EBUSY; 943 } else if (lf->userrefs == 0) { 944 /* 945 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 946 */ 947 printf("kldunload: attempt to unload file that was" 948 " loaded by the kernel\n"); 949 error = EBUSY; 950 } else { 951 #ifdef HWPMC_HOOKS 952 /* Save data needed by hwpmc(4) before unloading. */ 953 pkm.pm_address = (uintptr_t) lf->address; 954 pkm.pm_size = lf->size; 955 #endif 956 lf->userrefs--; 957 error = linker_file_unload(lf, flags); 958 if (error) 959 lf->userrefs++; 960 } 961 } else 962 error = ENOENT; 963 964 #ifdef HWPMC_HOOKS 965 if (error == 0) 966 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 967 #endif 968 KLD_UNLOCK(); 969 return (error); 970 } 971 972 int 973 kldunload(struct thread *td, struct kldunload_args *uap) 974 { 975 976 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 977 } 978 979 int 980 kldunloadf(struct thread *td, struct kldunloadf_args *uap) 981 { 982 983 if (uap->flags != LINKER_UNLOAD_NORMAL && 984 uap->flags != LINKER_UNLOAD_FORCE) 985 return (EINVAL); 986 return (kern_kldunload(td, uap->fileid, uap->flags)); 987 } 988 989 int 990 kldfind(struct thread *td, struct kldfind_args *uap) 991 { 992 char *pathname; 993 const char *filename; 994 linker_file_t lf; 995 int error; 996 997 #ifdef MAC 998 error = mac_kld_check_stat(td->td_ucred); 999 if (error) 1000 return (error); 1001 #endif 1002 1003 td->td_retval[0] = -1; 1004 1005 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1006 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1007 goto out; 1008 1009 filename = linker_basename(pathname); 1010 KLD_LOCK(); 1011 lf = linker_find_file_by_name(filename); 1012 if (lf) 1013 td->td_retval[0] = lf->id; 1014 else 1015 error = ENOENT; 1016 KLD_UNLOCK(); 1017 out: 1018 free(pathname, M_TEMP); 1019 return (error); 1020 } 1021 1022 int 1023 kldnext(struct thread *td, struct kldnext_args *uap) 1024 { 1025 linker_file_t lf; 1026 int error = 0; 1027 1028 #ifdef MAC 1029 error = mac_kld_check_stat(td->td_ucred); 1030 if (error) 1031 return (error); 1032 #endif 1033 1034 KLD_LOCK(); 1035 if (uap->fileid == 0) 1036 lf = TAILQ_FIRST(&linker_files); 1037 else { 1038 lf = linker_find_file_by_id(uap->fileid); 1039 if (lf == NULL) { 1040 error = ENOENT; 1041 goto out; 1042 } 1043 lf = TAILQ_NEXT(lf, link); 1044 } 1045 1046 /* Skip partially loaded files. */ 1047 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1048 lf = TAILQ_NEXT(lf, link); 1049 1050 if (lf) 1051 td->td_retval[0] = lf->id; 1052 else 1053 td->td_retval[0] = 0; 1054 out: 1055 KLD_UNLOCK(); 1056 return (error); 1057 } 1058 1059 int 1060 kldstat(struct thread *td, struct kldstat_args *uap) 1061 { 1062 struct kld_file_stat stat; 1063 linker_file_t lf; 1064 int error, namelen, version, version_num; 1065 1066 /* 1067 * Check the version of the user's structure. 1068 */ 1069 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) != 0) 1070 return (error); 1071 if (version == sizeof(struct kld_file_stat_1)) 1072 version_num = 1; 1073 else if (version == sizeof(struct kld_file_stat)) 1074 version_num = 2; 1075 else 1076 return (EINVAL); 1077 1078 #ifdef MAC 1079 error = mac_kld_check_stat(td->td_ucred); 1080 if (error) 1081 return (error); 1082 #endif 1083 1084 KLD_LOCK(); 1085 lf = linker_find_file_by_id(uap->fileid); 1086 if (lf == NULL) { 1087 KLD_UNLOCK(); 1088 return (ENOENT); 1089 } 1090 1091 /* Version 1 fields: */ 1092 namelen = strlen(lf->filename) + 1; 1093 if (namelen > MAXPATHLEN) 1094 namelen = MAXPATHLEN; 1095 bcopy(lf->filename, &stat.name[0], namelen); 1096 stat.refs = lf->refs; 1097 stat.id = lf->id; 1098 stat.address = lf->address; 1099 stat.size = lf->size; 1100 if (version_num > 1) { 1101 /* Version 2 fields: */ 1102 namelen = strlen(lf->pathname) + 1; 1103 if (namelen > MAXPATHLEN) 1104 namelen = MAXPATHLEN; 1105 bcopy(lf->pathname, &stat.pathname[0], namelen); 1106 } 1107 KLD_UNLOCK(); 1108 1109 td->td_retval[0] = 0; 1110 1111 return (copyout(&stat, uap->stat, version)); 1112 } 1113 1114 int 1115 kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1116 { 1117 linker_file_t lf; 1118 module_t mp; 1119 int error = 0; 1120 1121 #ifdef MAC 1122 error = mac_kld_check_stat(td->td_ucred); 1123 if (error) 1124 return (error); 1125 #endif 1126 1127 KLD_LOCK(); 1128 lf = linker_find_file_by_id(uap->fileid); 1129 if (lf) { 1130 MOD_SLOCK; 1131 mp = TAILQ_FIRST(&lf->modules); 1132 if (mp != NULL) 1133 td->td_retval[0] = module_getid(mp); 1134 else 1135 td->td_retval[0] = 0; 1136 MOD_SUNLOCK; 1137 } else 1138 error = ENOENT; 1139 KLD_UNLOCK(); 1140 return (error); 1141 } 1142 1143 int 1144 kldsym(struct thread *td, struct kldsym_args *uap) 1145 { 1146 char *symstr = NULL; 1147 c_linker_sym_t sym; 1148 linker_symval_t symval; 1149 linker_file_t lf; 1150 struct kld_sym_lookup lookup; 1151 int error = 0; 1152 1153 #ifdef MAC 1154 error = mac_kld_check_stat(td->td_ucred); 1155 if (error) 1156 return (error); 1157 #endif 1158 1159 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1160 return (error); 1161 if (lookup.version != sizeof(lookup) || 1162 uap->cmd != KLDSYM_LOOKUP) 1163 return (EINVAL); 1164 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1165 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1166 goto out; 1167 KLD_LOCK(); 1168 if (uap->fileid != 0) { 1169 lf = linker_find_file_by_id(uap->fileid); 1170 if (lf == NULL) 1171 error = ENOENT; 1172 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1173 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1174 lookup.symvalue = (uintptr_t) symval.value; 1175 lookup.symsize = symval.size; 1176 error = copyout(&lookup, uap->data, sizeof(lookup)); 1177 } else 1178 error = ENOENT; 1179 } else { 1180 TAILQ_FOREACH(lf, &linker_files, link) { 1181 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1182 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1183 lookup.symvalue = (uintptr_t)symval.value; 1184 lookup.symsize = symval.size; 1185 error = copyout(&lookup, uap->data, 1186 sizeof(lookup)); 1187 break; 1188 } 1189 } 1190 if (lf == NULL) 1191 error = ENOENT; 1192 } 1193 KLD_UNLOCK(); 1194 out: 1195 free(symstr, M_TEMP); 1196 return (error); 1197 } 1198 1199 /* 1200 * Preloaded module support 1201 */ 1202 1203 static modlist_t 1204 modlist_lookup(const char *name, int ver) 1205 { 1206 modlist_t mod; 1207 1208 TAILQ_FOREACH(mod, &found_modules, link) { 1209 if (strcmp(mod->name, name) == 0 && 1210 (ver == 0 || mod->version == ver)) 1211 return (mod); 1212 } 1213 return (NULL); 1214 } 1215 1216 static modlist_t 1217 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1218 { 1219 modlist_t mod, bestmod; 1220 int ver; 1221 1222 if (verinfo == NULL) 1223 return (modlist_lookup(name, 0)); 1224 bestmod = NULL; 1225 TAILQ_FOREACH(mod, &found_modules, link) { 1226 if (strcmp(mod->name, name) != 0) 1227 continue; 1228 ver = mod->version; 1229 if (ver == verinfo->md_ver_preferred) 1230 return (mod); 1231 if (ver >= verinfo->md_ver_minimum && 1232 ver <= verinfo->md_ver_maximum && 1233 (bestmod == NULL || ver > bestmod->version)) 1234 bestmod = mod; 1235 } 1236 return (bestmod); 1237 } 1238 1239 static modlist_t 1240 modlist_newmodule(const char *modname, int version, linker_file_t container) 1241 { 1242 modlist_t mod; 1243 1244 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1245 if (mod == NULL) 1246 panic("no memory for module list"); 1247 mod->container = container; 1248 mod->name = modname; 1249 mod->version = version; 1250 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1251 return (mod); 1252 } 1253 1254 static void 1255 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1256 struct mod_metadata **stop, int preload) 1257 { 1258 struct mod_metadata *mp, **mdp; 1259 const char *modname; 1260 int ver; 1261 1262 for (mdp = start; mdp < stop; mdp++) { 1263 mp = *mdp; 1264 if (mp->md_type != MDT_VERSION) 1265 continue; 1266 modname = mp->md_cval; 1267 ver = ((struct mod_version *)mp->md_data)->mv_version; 1268 if (modlist_lookup(modname, ver) != NULL) { 1269 printf("module %s already present!\n", modname); 1270 /* XXX what can we do? this is a build error. :-( */ 1271 continue; 1272 } 1273 modlist_newmodule(modname, ver, lf); 1274 } 1275 } 1276 1277 static void 1278 linker_preload(void *arg) 1279 { 1280 caddr_t modptr; 1281 const char *modname, *nmodname; 1282 char *modtype; 1283 linker_file_t lf, nlf; 1284 linker_class_t lc; 1285 int error; 1286 linker_file_list_t loaded_files; 1287 linker_file_list_t depended_files; 1288 struct mod_metadata *mp, *nmp; 1289 struct mod_metadata **start, **stop, **mdp, **nmdp; 1290 struct mod_depend *verinfo; 1291 int nver; 1292 int resolves; 1293 modlist_t mod; 1294 struct sysinit **si_start, **si_stop; 1295 1296 TAILQ_INIT(&loaded_files); 1297 TAILQ_INIT(&depended_files); 1298 TAILQ_INIT(&found_modules); 1299 error = 0; 1300 1301 modptr = NULL; 1302 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1303 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1304 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1305 if (modname == NULL) { 1306 printf("Preloaded module at %p does not have a" 1307 " name!\n", modptr); 1308 continue; 1309 } 1310 if (modtype == NULL) { 1311 printf("Preloaded module at %p does not have a type!\n", 1312 modptr); 1313 continue; 1314 } 1315 if (bootverbose) 1316 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1317 modptr); 1318 lf = NULL; 1319 TAILQ_FOREACH(lc, &classes, link) { 1320 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1321 if (!error) 1322 break; 1323 lf = NULL; 1324 } 1325 if (lf) 1326 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1327 } 1328 1329 /* 1330 * First get a list of stuff in the kernel. 1331 */ 1332 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1333 &stop, NULL) == 0) 1334 linker_addmodules(linker_kernel_file, start, stop, 1); 1335 1336 /* 1337 * This is a once-off kinky bubble sort to resolve relocation 1338 * dependency requirements. 1339 */ 1340 restart: 1341 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1342 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1343 &stop, NULL); 1344 /* 1345 * First, look to see if we would successfully link with this 1346 * stuff. 1347 */ 1348 resolves = 1; /* unless we know otherwise */ 1349 if (!error) { 1350 for (mdp = start; mdp < stop; mdp++) { 1351 mp = *mdp; 1352 if (mp->md_type != MDT_DEPEND) 1353 continue; 1354 modname = mp->md_cval; 1355 verinfo = mp->md_data; 1356 for (nmdp = start; nmdp < stop; nmdp++) { 1357 nmp = *nmdp; 1358 if (nmp->md_type != MDT_VERSION) 1359 continue; 1360 nmodname = nmp->md_cval; 1361 if (strcmp(modname, nmodname) == 0) 1362 break; 1363 } 1364 if (nmdp < stop) /* it's a self reference */ 1365 continue; 1366 1367 /* 1368 * ok, the module isn't here yet, we 1369 * are not finished 1370 */ 1371 if (modlist_lookup2(modname, verinfo) == NULL) 1372 resolves = 0; 1373 } 1374 } 1375 /* 1376 * OK, if we found our modules, we can link. So, "provide" 1377 * the modules inside and add it to the end of the link order 1378 * list. 1379 */ 1380 if (resolves) { 1381 if (!error) { 1382 for (mdp = start; mdp < stop; mdp++) { 1383 mp = *mdp; 1384 if (mp->md_type != MDT_VERSION) 1385 continue; 1386 modname = mp->md_cval; 1387 nver = ((struct mod_version *) 1388 mp->md_data)->mv_version; 1389 if (modlist_lookup(modname, 1390 nver) != NULL) { 1391 printf("module %s already" 1392 " present!\n", modname); 1393 TAILQ_REMOVE(&loaded_files, 1394 lf, loaded); 1395 linker_file_unload(lf, 1396 LINKER_UNLOAD_FORCE); 1397 /* we changed tailq next ptr */ 1398 goto restart; 1399 } 1400 modlist_newmodule(modname, nver, lf); 1401 } 1402 } 1403 TAILQ_REMOVE(&loaded_files, lf, loaded); 1404 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1405 /* 1406 * Since we provided modules, we need to restart the 1407 * sort so that the previous files that depend on us 1408 * have a chance. Also, we've busted the tailq next 1409 * pointer with the REMOVE. 1410 */ 1411 goto restart; 1412 } 1413 } 1414 1415 /* 1416 * At this point, we check to see what could not be resolved.. 1417 */ 1418 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1419 TAILQ_REMOVE(&loaded_files, lf, loaded); 1420 printf("KLD file %s is missing dependencies\n", lf->filename); 1421 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1422 } 1423 1424 /* 1425 * We made it. Finish off the linking in the order we determined. 1426 */ 1427 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1428 if (linker_kernel_file) { 1429 linker_kernel_file->refs++; 1430 error = linker_file_add_dependency(lf, 1431 linker_kernel_file); 1432 if (error) 1433 panic("cannot add dependency"); 1434 } 1435 lf->userrefs++; /* so we can (try to) kldunload it */ 1436 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1437 &stop, NULL); 1438 if (!error) { 1439 for (mdp = start; mdp < stop; mdp++) { 1440 mp = *mdp; 1441 if (mp->md_type != MDT_DEPEND) 1442 continue; 1443 modname = mp->md_cval; 1444 verinfo = mp->md_data; 1445 mod = modlist_lookup2(modname, verinfo); 1446 /* Don't count self-dependencies */ 1447 if (lf == mod->container) 1448 continue; 1449 mod->container->refs++; 1450 error = linker_file_add_dependency(lf, 1451 mod->container); 1452 if (error) 1453 panic("cannot add dependency"); 1454 } 1455 } 1456 /* 1457 * Now do relocation etc using the symbol search paths 1458 * established by the dependencies 1459 */ 1460 error = LINKER_LINK_PRELOAD_FINISH(lf); 1461 if (error) { 1462 TAILQ_REMOVE(&depended_files, lf, loaded); 1463 printf("KLD file %s - could not finalize loading\n", 1464 lf->filename); 1465 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1466 continue; 1467 } 1468 linker_file_register_modules(lf); 1469 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1470 &si_stop, NULL) == 0) 1471 sysinit_add(si_start, si_stop); 1472 linker_file_register_sysctls(lf); 1473 lf->flags |= LINKER_FILE_LINKED; 1474 } 1475 /* woohoo! we made it! */ 1476 } 1477 1478 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1479 1480 /* 1481 * Search for a not-loaded module by name. 1482 * 1483 * Modules may be found in the following locations: 1484 * 1485 * - preloaded (result is just the module name) - on disk (result is full path 1486 * to module) 1487 * 1488 * If the module name is qualified in any way (contains path, etc.) the we 1489 * simply return a copy of it. 1490 * 1491 * The search path can be manipulated via sysctl. Note that we use the ';' 1492 * character as a separator to be consistent with the bootloader. 1493 */ 1494 1495 static char linker_hintfile[] = "linker.hints"; 1496 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1497 1498 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1499 sizeof(linker_path), "module load search path"); 1500 1501 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1502 1503 static char *linker_ext_list[] = { 1504 "", 1505 ".ko", 1506 NULL 1507 }; 1508 1509 /* 1510 * Check if file actually exists either with or without extension listed in 1511 * the linker_ext_list. (probably should be generic for the rest of the 1512 * kernel) 1513 */ 1514 static char * 1515 linker_lookup_file(const char *path, int pathlen, const char *name, 1516 int namelen, struct vattr *vap) 1517 { 1518 struct nameidata nd; 1519 struct thread *td = curthread; /* XXX */ 1520 char *result, **cpp, *sep; 1521 int error, len, extlen, reclen, flags, vfslocked; 1522 enum vtype type; 1523 1524 extlen = 0; 1525 for (cpp = linker_ext_list; *cpp; cpp++) { 1526 len = strlen(*cpp); 1527 if (len > extlen) 1528 extlen = len; 1529 } 1530 extlen++; /* trailing '\0' */ 1531 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1532 1533 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1534 result = malloc(reclen, M_LINKER, M_WAITOK); 1535 for (cpp = linker_ext_list; *cpp; cpp++) { 1536 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1537 namelen, name, *cpp); 1538 /* 1539 * Attempt to open the file, and return the path if 1540 * we succeed and it's a regular file. 1541 */ 1542 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, result, td); 1543 flags = FREAD; 1544 error = vn_open(&nd, &flags, 0, NULL); 1545 if (error == 0) { 1546 vfslocked = NDHASGIANT(&nd); 1547 NDFREE(&nd, NDF_ONLY_PNBUF); 1548 type = nd.ni_vp->v_type; 1549 if (vap) 1550 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1551 VOP_UNLOCK(nd.ni_vp, 0, td); 1552 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1553 VFS_UNLOCK_GIANT(vfslocked); 1554 if (type == VREG) 1555 return (result); 1556 } 1557 } 1558 free(result, M_LINKER); 1559 return (NULL); 1560 } 1561 1562 #define INT_ALIGN(base, ptr) ptr = \ 1563 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1564 1565 /* 1566 * Lookup KLD which contains requested module in the "linker.hints" file. If 1567 * version specification is available, then try to find the best KLD. 1568 * Otherwise just find the latest one. 1569 */ 1570 static char * 1571 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1572 int modnamelen, struct mod_depend *verinfo) 1573 { 1574 struct thread *td = curthread; /* XXX */ 1575 struct ucred *cred = td ? td->td_ucred : NULL; 1576 struct nameidata nd; 1577 struct vattr vattr, mattr; 1578 u_char *hints = NULL; 1579 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1580 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1581 int vfslocked = 0; 1582 1583 result = NULL; 1584 bestver = found = 0; 1585 1586 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1587 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1588 strlen(sep) + 1; 1589 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1590 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1591 linker_hintfile); 1592 1593 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, pathbuf, td); 1594 flags = FREAD; 1595 error = vn_open(&nd, &flags, 0, NULL); 1596 if (error) 1597 goto bad; 1598 vfslocked = NDHASGIANT(&nd); 1599 NDFREE(&nd, NDF_ONLY_PNBUF); 1600 if (nd.ni_vp->v_type != VREG) 1601 goto bad; 1602 best = cp = NULL; 1603 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1604 if (error) 1605 goto bad; 1606 /* 1607 * XXX: we need to limit this number to some reasonable value 1608 */ 1609 if (vattr.va_size > 100 * 1024) { 1610 printf("hints file too large %ld\n", (long)vattr.va_size); 1611 goto bad; 1612 } 1613 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1614 if (hints == NULL) 1615 goto bad; 1616 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1617 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1618 if (error) 1619 goto bad; 1620 VOP_UNLOCK(nd.ni_vp, 0, td); 1621 vn_close(nd.ni_vp, FREAD, cred, td); 1622 VFS_UNLOCK_GIANT(vfslocked); 1623 nd.ni_vp = NULL; 1624 if (reclen != 0) { 1625 printf("can't read %d\n", reclen); 1626 goto bad; 1627 } 1628 intp = (int *)hints; 1629 ival = *intp++; 1630 if (ival != LINKER_HINTS_VERSION) { 1631 printf("hints file version mismatch %d\n", ival); 1632 goto bad; 1633 } 1634 bufend = hints + vattr.va_size; 1635 recptr = (u_char *)intp; 1636 clen = blen = 0; 1637 while (recptr < bufend && !found) { 1638 intp = (int *)recptr; 1639 reclen = *intp++; 1640 ival = *intp++; 1641 cp = (char *)intp; 1642 switch (ival) { 1643 case MDT_VERSION: 1644 clen = *cp++; 1645 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1646 break; 1647 cp += clen; 1648 INT_ALIGN(hints, cp); 1649 ival = *(int *)cp; 1650 cp += sizeof(int); 1651 clen = *cp++; 1652 if (verinfo == NULL || 1653 ival == verinfo->md_ver_preferred) { 1654 found = 1; 1655 break; 1656 } 1657 if (ival >= verinfo->md_ver_minimum && 1658 ival <= verinfo->md_ver_maximum && 1659 ival > bestver) { 1660 bestver = ival; 1661 best = cp; 1662 blen = clen; 1663 } 1664 break; 1665 default: 1666 break; 1667 } 1668 recptr += reclen + sizeof(int); 1669 } 1670 /* 1671 * Finally check if KLD is in the place 1672 */ 1673 if (found) 1674 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1675 else if (best) 1676 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1677 1678 /* 1679 * KLD is newer than hints file. What we should do now? 1680 */ 1681 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1682 printf("warning: KLD '%s' is newer than the linker.hints" 1683 " file\n", result); 1684 bad: 1685 free(pathbuf, M_LINKER); 1686 if (hints) 1687 free(hints, M_TEMP); 1688 if (nd.ni_vp != NULL) { 1689 VOP_UNLOCK(nd.ni_vp, 0, td); 1690 vn_close(nd.ni_vp, FREAD, cred, td); 1691 VFS_UNLOCK_GIANT(vfslocked); 1692 } 1693 /* 1694 * If nothing found or hints is absent - fallback to the old 1695 * way by using "kldname[.ko]" as module name. 1696 */ 1697 if (!found && !bestver && result == NULL) 1698 result = linker_lookup_file(path, pathlen, modname, 1699 modnamelen, NULL); 1700 return (result); 1701 } 1702 1703 /* 1704 * Lookup KLD which contains requested module in the all directories. 1705 */ 1706 static char * 1707 linker_search_module(const char *modname, int modnamelen, 1708 struct mod_depend *verinfo) 1709 { 1710 char *cp, *ep, *result; 1711 1712 /* 1713 * traverse the linker path 1714 */ 1715 for (cp = linker_path; *cp; cp = ep + 1) { 1716 /* find the end of this component */ 1717 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1718 result = linker_hints_lookup(cp, ep - cp, modname, 1719 modnamelen, verinfo); 1720 if (result != NULL) 1721 return (result); 1722 if (*ep == 0) 1723 break; 1724 } 1725 return (NULL); 1726 } 1727 1728 /* 1729 * Search for module in all directories listed in the linker_path. 1730 */ 1731 static char * 1732 linker_search_kld(const char *name) 1733 { 1734 char *cp, *ep, *result; 1735 int len; 1736 1737 /* qualified at all? */ 1738 if (index(name, '/')) 1739 return (linker_strdup(name)); 1740 1741 /* traverse the linker path */ 1742 len = strlen(name); 1743 for (ep = linker_path; *ep; ep++) { 1744 cp = ep; 1745 /* find the end of this component */ 1746 for (; *ep != 0 && *ep != ';'; ep++); 1747 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1748 if (result != NULL) 1749 return (result); 1750 } 1751 return (NULL); 1752 } 1753 1754 static const char * 1755 linker_basename(const char *path) 1756 { 1757 const char *filename; 1758 1759 filename = rindex(path, '/'); 1760 if (filename == NULL) 1761 return path; 1762 if (filename[1]) 1763 filename++; 1764 return (filename); 1765 } 1766 1767 #ifdef HWPMC_HOOKS 1768 1769 struct hwpmc_context { 1770 int nobjects; 1771 int nmappings; 1772 struct pmckern_map_in *kobase; 1773 }; 1774 1775 static int 1776 linker_hwpmc_list_object(linker_file_t lf, void *arg) 1777 { 1778 struct hwpmc_context *hc; 1779 1780 hc = arg; 1781 1782 /* If we run out of mappings, fail. */ 1783 if (hc->nobjects >= hc->nmappings) 1784 return (1); 1785 1786 /* Save the info for this linker file. */ 1787 hc->kobase[hc->nobjects].pm_file = lf->filename; 1788 hc->kobase[hc->nobjects].pm_address = (uintptr_t)lf->address; 1789 hc->nobjects++; 1790 return (0); 1791 } 1792 1793 /* 1794 * Inform hwpmc about the set of kernel modules currently loaded. 1795 */ 1796 void * 1797 linker_hwpmc_list_objects(void) 1798 { 1799 struct hwpmc_context hc; 1800 1801 hc.nmappings = 15; /* a reasonable default */ 1802 1803 retry: 1804 /* allocate nmappings+1 entries */ 1805 MALLOC(hc.kobase, struct pmckern_map_in *, 1806 (hc.nmappings + 1) * sizeof(struct pmckern_map_in), M_LINKER, 1807 M_WAITOK | M_ZERO); 1808 1809 hc.nobjects = 0; 1810 if (linker_file_foreach(linker_hwpmc_list_object, &hc) != 0) { 1811 hc.nmappings = hc.nobjects; 1812 FREE(hc.kobase, M_LINKER); 1813 goto retry; 1814 } 1815 1816 KASSERT(hc.nobjects > 0, ("linker_hpwmc_list_objects: no kernel " 1817 "objects?")); 1818 1819 /* The last entry of the malloced area comprises of all zeros. */ 1820 KASSERT(hc.kobase[hc.nobjects].pm_file == NULL, 1821 ("linker_hwpmc_list_objects: last object not NULL")); 1822 1823 return ((void *)hc.kobase); 1824 } 1825 #endif 1826 1827 /* 1828 * Find a file which contains given module and load it, if "parent" is not 1829 * NULL, register a reference to it. 1830 */ 1831 static int 1832 linker_load_module(const char *kldname, const char *modname, 1833 struct linker_file *parent, struct mod_depend *verinfo, 1834 struct linker_file **lfpp) 1835 { 1836 linker_file_t lfdep; 1837 const char *filename; 1838 char *pathname; 1839 int error; 1840 1841 KLD_LOCK_ASSERT(); 1842 if (modname == NULL) { 1843 /* 1844 * We have to load KLD 1845 */ 1846 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1847 " is not NULL")); 1848 pathname = linker_search_kld(kldname); 1849 } else { 1850 if (modlist_lookup2(modname, verinfo) != NULL) 1851 return (EEXIST); 1852 if (kldname != NULL) 1853 pathname = linker_strdup(kldname); 1854 else if (rootvnode == NULL) 1855 pathname = NULL; 1856 else 1857 /* 1858 * Need to find a KLD with required module 1859 */ 1860 pathname = linker_search_module(modname, 1861 strlen(modname), verinfo); 1862 } 1863 if (pathname == NULL) 1864 return (ENOENT); 1865 1866 /* 1867 * Can't load more than one file with the same basename XXX: 1868 * Actually it should be possible to have multiple KLDs with 1869 * the same basename but different path because they can 1870 * provide different versions of the same modules. 1871 */ 1872 filename = linker_basename(pathname); 1873 if (linker_find_file_by_name(filename)) 1874 error = EEXIST; 1875 else do { 1876 error = linker_load_file(pathname, &lfdep); 1877 if (error) 1878 break; 1879 if (modname && verinfo && 1880 modlist_lookup2(modname, verinfo) == NULL) { 1881 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1882 error = ENOENT; 1883 break; 1884 } 1885 if (parent) { 1886 error = linker_file_add_dependency(parent, lfdep); 1887 if (error) 1888 break; 1889 } 1890 if (lfpp) 1891 *lfpp = lfdep; 1892 } while (0); 1893 free(pathname, M_LINKER); 1894 return (error); 1895 } 1896 1897 /* 1898 * This routine is responsible for finding dependencies of userland initiated 1899 * kldload(2)'s of files. 1900 */ 1901 int 1902 linker_load_dependencies(linker_file_t lf) 1903 { 1904 linker_file_t lfdep; 1905 struct mod_metadata **start, **stop, **mdp, **nmdp; 1906 struct mod_metadata *mp, *nmp; 1907 struct mod_depend *verinfo; 1908 modlist_t mod; 1909 const char *modname, *nmodname; 1910 int ver, error = 0, count; 1911 1912 /* 1913 * All files are dependant on /kernel. 1914 */ 1915 KLD_LOCK_ASSERT(); 1916 if (linker_kernel_file) { 1917 linker_kernel_file->refs++; 1918 error = linker_file_add_dependency(lf, linker_kernel_file); 1919 if (error) 1920 return (error); 1921 } 1922 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1923 &count) != 0) 1924 return (0); 1925 for (mdp = start; mdp < stop; mdp++) { 1926 mp = *mdp; 1927 if (mp->md_type != MDT_VERSION) 1928 continue; 1929 modname = mp->md_cval; 1930 ver = ((struct mod_version *)mp->md_data)->mv_version; 1931 mod = modlist_lookup(modname, ver); 1932 if (mod != NULL) { 1933 printf("interface %s.%d already present in the KLD" 1934 " '%s'!\n", modname, ver, 1935 mod->container->filename); 1936 return (EEXIST); 1937 } 1938 } 1939 1940 for (mdp = start; mdp < stop; mdp++) { 1941 mp = *mdp; 1942 if (mp->md_type != MDT_DEPEND) 1943 continue; 1944 modname = mp->md_cval; 1945 verinfo = mp->md_data; 1946 nmodname = NULL; 1947 for (nmdp = start; nmdp < stop; nmdp++) { 1948 nmp = *nmdp; 1949 if (nmp->md_type != MDT_VERSION) 1950 continue; 1951 nmodname = nmp->md_cval; 1952 if (strcmp(modname, nmodname) == 0) 1953 break; 1954 } 1955 if (nmdp < stop)/* early exit, it's a self reference */ 1956 continue; 1957 mod = modlist_lookup2(modname, verinfo); 1958 if (mod) { /* woohoo, it's loaded already */ 1959 lfdep = mod->container; 1960 lfdep->refs++; 1961 error = linker_file_add_dependency(lf, lfdep); 1962 if (error) 1963 break; 1964 continue; 1965 } 1966 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1967 if (error) { 1968 printf("KLD %s: depends on %s - not available\n", 1969 lf->filename, modname); 1970 break; 1971 } 1972 } 1973 1974 if (error) 1975 return (error); 1976 linker_addmodules(lf, start, stop, 0); 1977 return (error); 1978 } 1979 1980 static int 1981 sysctl_kern_function_list_iterate(const char *name, void *opaque) 1982 { 1983 struct sysctl_req *req; 1984 1985 req = opaque; 1986 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1987 } 1988 1989 /* 1990 * Export a nul-separated, double-nul-terminated list of all function names 1991 * in the kernel. 1992 */ 1993 static int 1994 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1995 { 1996 linker_file_t lf; 1997 int error; 1998 1999 #ifdef MAC 2000 error = mac_kld_check_stat(req->td->td_ucred); 2001 if (error) 2002 return (error); 2003 #endif 2004 error = sysctl_wire_old_buffer(req, 0); 2005 if (error != 0) 2006 return (error); 2007 KLD_LOCK(); 2008 TAILQ_FOREACH(lf, &linker_files, link) { 2009 error = LINKER_EACH_FUNCTION_NAME(lf, 2010 sysctl_kern_function_list_iterate, req); 2011 if (error) { 2012 KLD_UNLOCK(); 2013 return (error); 2014 } 2015 } 2016 KLD_UNLOCK(); 2017 return (SYSCTL_OUT(req, "", 1)); 2018 } 2019 2020 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 2021 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 2022