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 /* 694 * List all functions in a file. 695 */ 696 int 697 linker_file_function_listall(linker_file_t lf, 698 int (*callback_func)(linker_file_t, linker_symval_t *, void *), void *arg) 699 { 700 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 701 } 702 703 caddr_t 704 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 705 { 706 caddr_t sym; 707 int locked; 708 709 locked = KLD_LOCKED(); 710 if (!locked) 711 KLD_LOCK(); 712 sym = linker_file_lookup_symbol_internal(file, name, deps); 713 if (!locked) 714 KLD_UNLOCK(); 715 return (sym); 716 } 717 718 static caddr_t 719 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 720 int deps) 721 { 722 c_linker_sym_t sym; 723 linker_symval_t symval; 724 caddr_t address; 725 size_t common_size = 0; 726 int i; 727 728 KLD_LOCK_ASSERT(); 729 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 730 file, name, deps)); 731 732 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 733 LINKER_SYMBOL_VALUES(file, sym, &symval); 734 if (symval.value == 0) 735 /* 736 * For commons, first look them up in the 737 * dependencies and only allocate space if not found 738 * there. 739 */ 740 common_size = symval.size; 741 else { 742 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 743 ".value=%p\n", symval.value)); 744 return (symval.value); 745 } 746 } 747 if (deps) { 748 for (i = 0; i < file->ndeps; i++) { 749 address = linker_file_lookup_symbol_internal( 750 file->deps[i], name, 0); 751 if (address) { 752 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 753 " deps value=%p\n", address)); 754 return (address); 755 } 756 } 757 } 758 if (common_size > 0) { 759 /* 760 * This is a common symbol which was not found in the 761 * dependencies. We maintain a simple common symbol table in 762 * the file object. 763 */ 764 struct common_symbol *cp; 765 766 STAILQ_FOREACH(cp, &file->common, link) { 767 if (strcmp(cp->name, name) == 0) { 768 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 769 " old common value=%p\n", cp->address)); 770 return (cp->address); 771 } 772 } 773 /* 774 * Round the symbol size up to align. 775 */ 776 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 777 cp = malloc(sizeof(struct common_symbol) 778 + common_size + strlen(name) + 1, M_LINKER, 779 M_WAITOK | M_ZERO); 780 cp->address = (caddr_t)(cp + 1); 781 cp->name = cp->address + common_size; 782 strcpy(cp->name, name); 783 bzero(cp->address, common_size); 784 STAILQ_INSERT_TAIL(&file->common, cp, link); 785 786 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 787 " value=%p\n", cp->address)); 788 return (cp->address); 789 } 790 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 791 return (0); 792 } 793 794 #ifdef DDB 795 /* 796 * DDB Helpers. DDB has to look across multiple files with their own symbol 797 * tables and string tables. 798 * 799 * Note that we do not obey list locking protocols here. We really don't need 800 * DDB to hang because somebody's got the lock held. We'll take the chance 801 * that the files list is inconsistant instead. 802 */ 803 804 int 805 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 806 { 807 linker_file_t lf; 808 809 TAILQ_FOREACH(lf, &linker_files, link) { 810 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 811 return (0); 812 } 813 return (ENOENT); 814 } 815 816 int 817 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 818 { 819 linker_file_t lf; 820 c_linker_sym_t best, es; 821 u_long diff, bestdiff, off; 822 823 best = 0; 824 off = (uintptr_t)value; 825 bestdiff = off; 826 TAILQ_FOREACH(lf, &linker_files, link) { 827 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 828 continue; 829 if (es != 0 && diff < bestdiff) { 830 best = es; 831 bestdiff = diff; 832 } 833 if (bestdiff == 0) 834 break; 835 } 836 if (best) { 837 *sym = best; 838 *diffp = bestdiff; 839 return (0); 840 } else { 841 *sym = 0; 842 *diffp = off; 843 return (ENOENT); 844 } 845 } 846 847 int 848 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 849 { 850 linker_file_t lf; 851 852 TAILQ_FOREACH(lf, &linker_files, link) { 853 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 854 return (0); 855 } 856 return (ENOENT); 857 } 858 #endif 859 860 /* 861 * Syscalls. 862 */ 863 int 864 kern_kldload(struct thread *td, const char *file, int *fileid) 865 { 866 #ifdef HWPMC_HOOKS 867 struct pmckern_map_in pkm; 868 #endif 869 const char *kldname, *modname; 870 linker_file_t lf; 871 int error; 872 873 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 874 return (error); 875 876 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 877 return (error); 878 879 /* 880 * If file does not contain a qualified name or any dot in it 881 * (kldname.ko, or kldname.ver.ko) treat it as an interface 882 * name. 883 */ 884 if (index(file, '/') || index(file, '.')) { 885 kldname = file; 886 modname = NULL; 887 } else { 888 kldname = NULL; 889 modname = file; 890 } 891 892 KLD_LOCK(); 893 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 894 if (error) 895 goto unlock; 896 #ifdef HWPMC_HOOKS 897 pkm.pm_file = lf->filename; 898 pkm.pm_address = (uintptr_t) lf->address; 899 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 900 #endif 901 lf->userrefs++; 902 if (fileid != NULL) 903 *fileid = lf->id; 904 unlock: 905 KLD_UNLOCK(); 906 return (error); 907 } 908 909 int 910 kldload(struct thread *td, struct kldload_args *uap) 911 { 912 char *pathname = NULL; 913 int error, fileid; 914 915 td->td_retval[0] = -1; 916 917 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 918 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 919 if (error == 0) { 920 error = kern_kldload(td, pathname, &fileid); 921 if (error == 0) 922 td->td_retval[0] = fileid; 923 } 924 free(pathname, M_TEMP); 925 return (error); 926 } 927 928 int 929 kern_kldunload(struct thread *td, int fileid, int flags) 930 { 931 #ifdef HWPMC_HOOKS 932 struct pmckern_map_out pkm; 933 #endif 934 linker_file_t lf; 935 int error = 0; 936 937 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 938 return (error); 939 940 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 941 return (error); 942 943 KLD_LOCK(); 944 lf = linker_find_file_by_id(fileid); 945 if (lf) { 946 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 947 948 /* Check if there are DTrace probes enabled on this file. */ 949 if (lf->nenabled > 0) { 950 printf("kldunload: attempt to unload file that has" 951 " DTrace probes enabled\n"); 952 error = EBUSY; 953 } else if (lf->userrefs == 0) { 954 /* 955 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 956 */ 957 printf("kldunload: attempt to unload file that was" 958 " loaded by the kernel\n"); 959 error = EBUSY; 960 } else { 961 #ifdef HWPMC_HOOKS 962 /* Save data needed by hwpmc(4) before unloading. */ 963 pkm.pm_address = (uintptr_t) lf->address; 964 pkm.pm_size = lf->size; 965 #endif 966 lf->userrefs--; 967 error = linker_file_unload(lf, flags); 968 if (error) 969 lf->userrefs++; 970 } 971 } else 972 error = ENOENT; 973 974 #ifdef HWPMC_HOOKS 975 if (error == 0) 976 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 977 #endif 978 KLD_UNLOCK(); 979 return (error); 980 } 981 982 int 983 kldunload(struct thread *td, struct kldunload_args *uap) 984 { 985 986 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 987 } 988 989 int 990 kldunloadf(struct thread *td, struct kldunloadf_args *uap) 991 { 992 993 if (uap->flags != LINKER_UNLOAD_NORMAL && 994 uap->flags != LINKER_UNLOAD_FORCE) 995 return (EINVAL); 996 return (kern_kldunload(td, uap->fileid, uap->flags)); 997 } 998 999 int 1000 kldfind(struct thread *td, struct kldfind_args *uap) 1001 { 1002 char *pathname; 1003 const char *filename; 1004 linker_file_t lf; 1005 int error; 1006 1007 #ifdef MAC 1008 error = mac_kld_check_stat(td->td_ucred); 1009 if (error) 1010 return (error); 1011 #endif 1012 1013 td->td_retval[0] = -1; 1014 1015 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1016 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1017 goto out; 1018 1019 filename = linker_basename(pathname); 1020 KLD_LOCK(); 1021 lf = linker_find_file_by_name(filename); 1022 if (lf) 1023 td->td_retval[0] = lf->id; 1024 else 1025 error = ENOENT; 1026 KLD_UNLOCK(); 1027 out: 1028 free(pathname, M_TEMP); 1029 return (error); 1030 } 1031 1032 int 1033 kldnext(struct thread *td, struct kldnext_args *uap) 1034 { 1035 linker_file_t lf; 1036 int error = 0; 1037 1038 #ifdef MAC 1039 error = mac_kld_check_stat(td->td_ucred); 1040 if (error) 1041 return (error); 1042 #endif 1043 1044 KLD_LOCK(); 1045 if (uap->fileid == 0) 1046 lf = TAILQ_FIRST(&linker_files); 1047 else { 1048 lf = linker_find_file_by_id(uap->fileid); 1049 if (lf == NULL) { 1050 error = ENOENT; 1051 goto out; 1052 } 1053 lf = TAILQ_NEXT(lf, link); 1054 } 1055 1056 /* Skip partially loaded files. */ 1057 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1058 lf = TAILQ_NEXT(lf, link); 1059 1060 if (lf) 1061 td->td_retval[0] = lf->id; 1062 else 1063 td->td_retval[0] = 0; 1064 out: 1065 KLD_UNLOCK(); 1066 return (error); 1067 } 1068 1069 int 1070 kldstat(struct thread *td, struct kldstat_args *uap) 1071 { 1072 struct kld_file_stat stat; 1073 linker_file_t lf; 1074 int error, namelen, version, version_num; 1075 1076 /* 1077 * Check the version of the user's structure. 1078 */ 1079 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) != 0) 1080 return (error); 1081 if (version == sizeof(struct kld_file_stat_1)) 1082 version_num = 1; 1083 else if (version == sizeof(struct kld_file_stat)) 1084 version_num = 2; 1085 else 1086 return (EINVAL); 1087 1088 #ifdef MAC 1089 error = mac_kld_check_stat(td->td_ucred); 1090 if (error) 1091 return (error); 1092 #endif 1093 1094 KLD_LOCK(); 1095 lf = linker_find_file_by_id(uap->fileid); 1096 if (lf == NULL) { 1097 KLD_UNLOCK(); 1098 return (ENOENT); 1099 } 1100 1101 /* Version 1 fields: */ 1102 namelen = strlen(lf->filename) + 1; 1103 if (namelen > MAXPATHLEN) 1104 namelen = MAXPATHLEN; 1105 bcopy(lf->filename, &stat.name[0], namelen); 1106 stat.refs = lf->refs; 1107 stat.id = lf->id; 1108 stat.address = lf->address; 1109 stat.size = lf->size; 1110 if (version_num > 1) { 1111 /* Version 2 fields: */ 1112 namelen = strlen(lf->pathname) + 1; 1113 if (namelen > MAXPATHLEN) 1114 namelen = MAXPATHLEN; 1115 bcopy(lf->pathname, &stat.pathname[0], namelen); 1116 } 1117 KLD_UNLOCK(); 1118 1119 td->td_retval[0] = 0; 1120 1121 return (copyout(&stat, uap->stat, version)); 1122 } 1123 1124 int 1125 kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1126 { 1127 linker_file_t lf; 1128 module_t mp; 1129 int error = 0; 1130 1131 #ifdef MAC 1132 error = mac_kld_check_stat(td->td_ucred); 1133 if (error) 1134 return (error); 1135 #endif 1136 1137 KLD_LOCK(); 1138 lf = linker_find_file_by_id(uap->fileid); 1139 if (lf) { 1140 MOD_SLOCK; 1141 mp = TAILQ_FIRST(&lf->modules); 1142 if (mp != NULL) 1143 td->td_retval[0] = module_getid(mp); 1144 else 1145 td->td_retval[0] = 0; 1146 MOD_SUNLOCK; 1147 } else 1148 error = ENOENT; 1149 KLD_UNLOCK(); 1150 return (error); 1151 } 1152 1153 int 1154 kldsym(struct thread *td, struct kldsym_args *uap) 1155 { 1156 char *symstr = NULL; 1157 c_linker_sym_t sym; 1158 linker_symval_t symval; 1159 linker_file_t lf; 1160 struct kld_sym_lookup lookup; 1161 int error = 0; 1162 1163 #ifdef MAC 1164 error = mac_kld_check_stat(td->td_ucred); 1165 if (error) 1166 return (error); 1167 #endif 1168 1169 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1170 return (error); 1171 if (lookup.version != sizeof(lookup) || 1172 uap->cmd != KLDSYM_LOOKUP) 1173 return (EINVAL); 1174 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1175 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1176 goto out; 1177 KLD_LOCK(); 1178 if (uap->fileid != 0) { 1179 lf = linker_find_file_by_id(uap->fileid); 1180 if (lf == NULL) 1181 error = ENOENT; 1182 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1183 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1184 lookup.symvalue = (uintptr_t) symval.value; 1185 lookup.symsize = symval.size; 1186 error = copyout(&lookup, uap->data, sizeof(lookup)); 1187 } else 1188 error = ENOENT; 1189 } else { 1190 TAILQ_FOREACH(lf, &linker_files, link) { 1191 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1192 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1193 lookup.symvalue = (uintptr_t)symval.value; 1194 lookup.symsize = symval.size; 1195 error = copyout(&lookup, uap->data, 1196 sizeof(lookup)); 1197 break; 1198 } 1199 } 1200 if (lf == NULL) 1201 error = ENOENT; 1202 } 1203 KLD_UNLOCK(); 1204 out: 1205 free(symstr, M_TEMP); 1206 return (error); 1207 } 1208 1209 /* 1210 * Preloaded module support 1211 */ 1212 1213 static modlist_t 1214 modlist_lookup(const char *name, int ver) 1215 { 1216 modlist_t mod; 1217 1218 TAILQ_FOREACH(mod, &found_modules, link) { 1219 if (strcmp(mod->name, name) == 0 && 1220 (ver == 0 || mod->version == ver)) 1221 return (mod); 1222 } 1223 return (NULL); 1224 } 1225 1226 static modlist_t 1227 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1228 { 1229 modlist_t mod, bestmod; 1230 int ver; 1231 1232 if (verinfo == NULL) 1233 return (modlist_lookup(name, 0)); 1234 bestmod = NULL; 1235 TAILQ_FOREACH(mod, &found_modules, link) { 1236 if (strcmp(mod->name, name) != 0) 1237 continue; 1238 ver = mod->version; 1239 if (ver == verinfo->md_ver_preferred) 1240 return (mod); 1241 if (ver >= verinfo->md_ver_minimum && 1242 ver <= verinfo->md_ver_maximum && 1243 (bestmod == NULL || ver > bestmod->version)) 1244 bestmod = mod; 1245 } 1246 return (bestmod); 1247 } 1248 1249 static modlist_t 1250 modlist_newmodule(const char *modname, int version, linker_file_t container) 1251 { 1252 modlist_t mod; 1253 1254 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1255 if (mod == NULL) 1256 panic("no memory for module list"); 1257 mod->container = container; 1258 mod->name = modname; 1259 mod->version = version; 1260 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1261 return (mod); 1262 } 1263 1264 static void 1265 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1266 struct mod_metadata **stop, int preload) 1267 { 1268 struct mod_metadata *mp, **mdp; 1269 const char *modname; 1270 int ver; 1271 1272 for (mdp = start; mdp < stop; mdp++) { 1273 mp = *mdp; 1274 if (mp->md_type != MDT_VERSION) 1275 continue; 1276 modname = mp->md_cval; 1277 ver = ((struct mod_version *)mp->md_data)->mv_version; 1278 if (modlist_lookup(modname, ver) != NULL) { 1279 printf("module %s already present!\n", modname); 1280 /* XXX what can we do? this is a build error. :-( */ 1281 continue; 1282 } 1283 modlist_newmodule(modname, ver, lf); 1284 } 1285 } 1286 1287 static void 1288 linker_preload(void *arg) 1289 { 1290 caddr_t modptr; 1291 const char *modname, *nmodname; 1292 char *modtype; 1293 linker_file_t lf, nlf; 1294 linker_class_t lc; 1295 int error; 1296 linker_file_list_t loaded_files; 1297 linker_file_list_t depended_files; 1298 struct mod_metadata *mp, *nmp; 1299 struct mod_metadata **start, **stop, **mdp, **nmdp; 1300 struct mod_depend *verinfo; 1301 int nver; 1302 int resolves; 1303 modlist_t mod; 1304 struct sysinit **si_start, **si_stop; 1305 1306 TAILQ_INIT(&loaded_files); 1307 TAILQ_INIT(&depended_files); 1308 TAILQ_INIT(&found_modules); 1309 error = 0; 1310 1311 modptr = NULL; 1312 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1313 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1314 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1315 if (modname == NULL) { 1316 printf("Preloaded module at %p does not have a" 1317 " name!\n", modptr); 1318 continue; 1319 } 1320 if (modtype == NULL) { 1321 printf("Preloaded module at %p does not have a type!\n", 1322 modptr); 1323 continue; 1324 } 1325 if (bootverbose) 1326 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1327 modptr); 1328 lf = NULL; 1329 TAILQ_FOREACH(lc, &classes, link) { 1330 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1331 if (!error) 1332 break; 1333 lf = NULL; 1334 } 1335 if (lf) 1336 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1337 } 1338 1339 /* 1340 * First get a list of stuff in the kernel. 1341 */ 1342 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1343 &stop, NULL) == 0) 1344 linker_addmodules(linker_kernel_file, start, stop, 1); 1345 1346 /* 1347 * This is a once-off kinky bubble sort to resolve relocation 1348 * dependency requirements. 1349 */ 1350 restart: 1351 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1352 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1353 &stop, NULL); 1354 /* 1355 * First, look to see if we would successfully link with this 1356 * stuff. 1357 */ 1358 resolves = 1; /* unless we know otherwise */ 1359 if (!error) { 1360 for (mdp = start; mdp < stop; mdp++) { 1361 mp = *mdp; 1362 if (mp->md_type != MDT_DEPEND) 1363 continue; 1364 modname = mp->md_cval; 1365 verinfo = mp->md_data; 1366 for (nmdp = start; nmdp < stop; nmdp++) { 1367 nmp = *nmdp; 1368 if (nmp->md_type != MDT_VERSION) 1369 continue; 1370 nmodname = nmp->md_cval; 1371 if (strcmp(modname, nmodname) == 0) 1372 break; 1373 } 1374 if (nmdp < stop) /* it's a self reference */ 1375 continue; 1376 1377 /* 1378 * ok, the module isn't here yet, we 1379 * are not finished 1380 */ 1381 if (modlist_lookup2(modname, verinfo) == NULL) 1382 resolves = 0; 1383 } 1384 } 1385 /* 1386 * OK, if we found our modules, we can link. So, "provide" 1387 * the modules inside and add it to the end of the link order 1388 * list. 1389 */ 1390 if (resolves) { 1391 if (!error) { 1392 for (mdp = start; mdp < stop; mdp++) { 1393 mp = *mdp; 1394 if (mp->md_type != MDT_VERSION) 1395 continue; 1396 modname = mp->md_cval; 1397 nver = ((struct mod_version *) 1398 mp->md_data)->mv_version; 1399 if (modlist_lookup(modname, 1400 nver) != NULL) { 1401 printf("module %s already" 1402 " present!\n", modname); 1403 TAILQ_REMOVE(&loaded_files, 1404 lf, loaded); 1405 linker_file_unload(lf, 1406 LINKER_UNLOAD_FORCE); 1407 /* we changed tailq next ptr */ 1408 goto restart; 1409 } 1410 modlist_newmodule(modname, nver, lf); 1411 } 1412 } 1413 TAILQ_REMOVE(&loaded_files, lf, loaded); 1414 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1415 /* 1416 * Since we provided modules, we need to restart the 1417 * sort so that the previous files that depend on us 1418 * have a chance. Also, we've busted the tailq next 1419 * pointer with the REMOVE. 1420 */ 1421 goto restart; 1422 } 1423 } 1424 1425 /* 1426 * At this point, we check to see what could not be resolved.. 1427 */ 1428 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1429 TAILQ_REMOVE(&loaded_files, lf, loaded); 1430 printf("KLD file %s is missing dependencies\n", lf->filename); 1431 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1432 } 1433 1434 /* 1435 * We made it. Finish off the linking in the order we determined. 1436 */ 1437 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1438 if (linker_kernel_file) { 1439 linker_kernel_file->refs++; 1440 error = linker_file_add_dependency(lf, 1441 linker_kernel_file); 1442 if (error) 1443 panic("cannot add dependency"); 1444 } 1445 lf->userrefs++; /* so we can (try to) kldunload it */ 1446 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1447 &stop, NULL); 1448 if (!error) { 1449 for (mdp = start; mdp < stop; mdp++) { 1450 mp = *mdp; 1451 if (mp->md_type != MDT_DEPEND) 1452 continue; 1453 modname = mp->md_cval; 1454 verinfo = mp->md_data; 1455 mod = modlist_lookup2(modname, verinfo); 1456 /* Don't count self-dependencies */ 1457 if (lf == mod->container) 1458 continue; 1459 mod->container->refs++; 1460 error = linker_file_add_dependency(lf, 1461 mod->container); 1462 if (error) 1463 panic("cannot add dependency"); 1464 } 1465 } 1466 /* 1467 * Now do relocation etc using the symbol search paths 1468 * established by the dependencies 1469 */ 1470 error = LINKER_LINK_PRELOAD_FINISH(lf); 1471 if (error) { 1472 TAILQ_REMOVE(&depended_files, lf, loaded); 1473 printf("KLD file %s - could not finalize loading\n", 1474 lf->filename); 1475 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1476 continue; 1477 } 1478 linker_file_register_modules(lf); 1479 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1480 &si_stop, NULL) == 0) 1481 sysinit_add(si_start, si_stop); 1482 linker_file_register_sysctls(lf); 1483 lf->flags |= LINKER_FILE_LINKED; 1484 } 1485 /* woohoo! we made it! */ 1486 } 1487 1488 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1489 1490 /* 1491 * Search for a not-loaded module by name. 1492 * 1493 * Modules may be found in the following locations: 1494 * 1495 * - preloaded (result is just the module name) - on disk (result is full path 1496 * to module) 1497 * 1498 * If the module name is qualified in any way (contains path, etc.) the we 1499 * simply return a copy of it. 1500 * 1501 * The search path can be manipulated via sysctl. Note that we use the ';' 1502 * character as a separator to be consistent with the bootloader. 1503 */ 1504 1505 static char linker_hintfile[] = "linker.hints"; 1506 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1507 1508 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1509 sizeof(linker_path), "module load search path"); 1510 1511 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1512 1513 static char *linker_ext_list[] = { 1514 "", 1515 ".ko", 1516 NULL 1517 }; 1518 1519 /* 1520 * Check if file actually exists either with or without extension listed in 1521 * the linker_ext_list. (probably should be generic for the rest of the 1522 * kernel) 1523 */ 1524 static char * 1525 linker_lookup_file(const char *path, int pathlen, const char *name, 1526 int namelen, struct vattr *vap) 1527 { 1528 struct nameidata nd; 1529 struct thread *td = curthread; /* XXX */ 1530 char *result, **cpp, *sep; 1531 int error, len, extlen, reclen, flags, vfslocked; 1532 enum vtype type; 1533 1534 extlen = 0; 1535 for (cpp = linker_ext_list; *cpp; cpp++) { 1536 len = strlen(*cpp); 1537 if (len > extlen) 1538 extlen = len; 1539 } 1540 extlen++; /* trailing '\0' */ 1541 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1542 1543 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1544 result = malloc(reclen, M_LINKER, M_WAITOK); 1545 for (cpp = linker_ext_list; *cpp; cpp++) { 1546 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1547 namelen, name, *cpp); 1548 /* 1549 * Attempt to open the file, and return the path if 1550 * we succeed and it's a regular file. 1551 */ 1552 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, result, td); 1553 flags = FREAD; 1554 error = vn_open(&nd, &flags, 0, NULL); 1555 if (error == 0) { 1556 vfslocked = NDHASGIANT(&nd); 1557 NDFREE(&nd, NDF_ONLY_PNBUF); 1558 type = nd.ni_vp->v_type; 1559 if (vap) 1560 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1561 VOP_UNLOCK(nd.ni_vp, 0, td); 1562 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1563 VFS_UNLOCK_GIANT(vfslocked); 1564 if (type == VREG) 1565 return (result); 1566 } 1567 } 1568 free(result, M_LINKER); 1569 return (NULL); 1570 } 1571 1572 #define INT_ALIGN(base, ptr) ptr = \ 1573 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1574 1575 /* 1576 * Lookup KLD which contains requested module in the "linker.hints" file. If 1577 * version specification is available, then try to find the best KLD. 1578 * Otherwise just find the latest one. 1579 */ 1580 static char * 1581 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1582 int modnamelen, struct mod_depend *verinfo) 1583 { 1584 struct thread *td = curthread; /* XXX */ 1585 struct ucred *cred = td ? td->td_ucred : NULL; 1586 struct nameidata nd; 1587 struct vattr vattr, mattr; 1588 u_char *hints = NULL; 1589 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1590 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1591 int vfslocked = 0; 1592 1593 result = NULL; 1594 bestver = found = 0; 1595 1596 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1597 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1598 strlen(sep) + 1; 1599 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1600 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1601 linker_hintfile); 1602 1603 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, pathbuf, td); 1604 flags = FREAD; 1605 error = vn_open(&nd, &flags, 0, NULL); 1606 if (error) 1607 goto bad; 1608 vfslocked = NDHASGIANT(&nd); 1609 NDFREE(&nd, NDF_ONLY_PNBUF); 1610 if (nd.ni_vp->v_type != VREG) 1611 goto bad; 1612 best = cp = NULL; 1613 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1614 if (error) 1615 goto bad; 1616 /* 1617 * XXX: we need to limit this number to some reasonable value 1618 */ 1619 if (vattr.va_size > 100 * 1024) { 1620 printf("hints file too large %ld\n", (long)vattr.va_size); 1621 goto bad; 1622 } 1623 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1624 if (hints == NULL) 1625 goto bad; 1626 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1627 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1628 if (error) 1629 goto bad; 1630 VOP_UNLOCK(nd.ni_vp, 0, td); 1631 vn_close(nd.ni_vp, FREAD, cred, td); 1632 VFS_UNLOCK_GIANT(vfslocked); 1633 nd.ni_vp = NULL; 1634 if (reclen != 0) { 1635 printf("can't read %d\n", reclen); 1636 goto bad; 1637 } 1638 intp = (int *)hints; 1639 ival = *intp++; 1640 if (ival != LINKER_HINTS_VERSION) { 1641 printf("hints file version mismatch %d\n", ival); 1642 goto bad; 1643 } 1644 bufend = hints + vattr.va_size; 1645 recptr = (u_char *)intp; 1646 clen = blen = 0; 1647 while (recptr < bufend && !found) { 1648 intp = (int *)recptr; 1649 reclen = *intp++; 1650 ival = *intp++; 1651 cp = (char *)intp; 1652 switch (ival) { 1653 case MDT_VERSION: 1654 clen = *cp++; 1655 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1656 break; 1657 cp += clen; 1658 INT_ALIGN(hints, cp); 1659 ival = *(int *)cp; 1660 cp += sizeof(int); 1661 clen = *cp++; 1662 if (verinfo == NULL || 1663 ival == verinfo->md_ver_preferred) { 1664 found = 1; 1665 break; 1666 } 1667 if (ival >= verinfo->md_ver_minimum && 1668 ival <= verinfo->md_ver_maximum && 1669 ival > bestver) { 1670 bestver = ival; 1671 best = cp; 1672 blen = clen; 1673 } 1674 break; 1675 default: 1676 break; 1677 } 1678 recptr += reclen + sizeof(int); 1679 } 1680 /* 1681 * Finally check if KLD is in the place 1682 */ 1683 if (found) 1684 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1685 else if (best) 1686 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1687 1688 /* 1689 * KLD is newer than hints file. What we should do now? 1690 */ 1691 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1692 printf("warning: KLD '%s' is newer than the linker.hints" 1693 " file\n", result); 1694 bad: 1695 free(pathbuf, M_LINKER); 1696 if (hints) 1697 free(hints, M_TEMP); 1698 if (nd.ni_vp != NULL) { 1699 VOP_UNLOCK(nd.ni_vp, 0, td); 1700 vn_close(nd.ni_vp, FREAD, cred, td); 1701 VFS_UNLOCK_GIANT(vfslocked); 1702 } 1703 /* 1704 * If nothing found or hints is absent - fallback to the old 1705 * way by using "kldname[.ko]" as module name. 1706 */ 1707 if (!found && !bestver && result == NULL) 1708 result = linker_lookup_file(path, pathlen, modname, 1709 modnamelen, NULL); 1710 return (result); 1711 } 1712 1713 /* 1714 * Lookup KLD which contains requested module in the all directories. 1715 */ 1716 static char * 1717 linker_search_module(const char *modname, int modnamelen, 1718 struct mod_depend *verinfo) 1719 { 1720 char *cp, *ep, *result; 1721 1722 /* 1723 * traverse the linker path 1724 */ 1725 for (cp = linker_path; *cp; cp = ep + 1) { 1726 /* find the end of this component */ 1727 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1728 result = linker_hints_lookup(cp, ep - cp, modname, 1729 modnamelen, verinfo); 1730 if (result != NULL) 1731 return (result); 1732 if (*ep == 0) 1733 break; 1734 } 1735 return (NULL); 1736 } 1737 1738 /* 1739 * Search for module in all directories listed in the linker_path. 1740 */ 1741 static char * 1742 linker_search_kld(const char *name) 1743 { 1744 char *cp, *ep, *result; 1745 int len; 1746 1747 /* qualified at all? */ 1748 if (index(name, '/')) 1749 return (linker_strdup(name)); 1750 1751 /* traverse the linker path */ 1752 len = strlen(name); 1753 for (ep = linker_path; *ep; ep++) { 1754 cp = ep; 1755 /* find the end of this component */ 1756 for (; *ep != 0 && *ep != ';'; ep++); 1757 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1758 if (result != NULL) 1759 return (result); 1760 } 1761 return (NULL); 1762 } 1763 1764 static const char * 1765 linker_basename(const char *path) 1766 { 1767 const char *filename; 1768 1769 filename = rindex(path, '/'); 1770 if (filename == NULL) 1771 return path; 1772 if (filename[1]) 1773 filename++; 1774 return (filename); 1775 } 1776 1777 #ifdef HWPMC_HOOKS 1778 1779 struct hwpmc_context { 1780 int nobjects; 1781 int nmappings; 1782 struct pmckern_map_in *kobase; 1783 }; 1784 1785 static int 1786 linker_hwpmc_list_object(linker_file_t lf, void *arg) 1787 { 1788 struct hwpmc_context *hc; 1789 1790 hc = arg; 1791 1792 /* If we run out of mappings, fail. */ 1793 if (hc->nobjects >= hc->nmappings) 1794 return (1); 1795 1796 /* Save the info for this linker file. */ 1797 hc->kobase[hc->nobjects].pm_file = lf->filename; 1798 hc->kobase[hc->nobjects].pm_address = (uintptr_t)lf->address; 1799 hc->nobjects++; 1800 return (0); 1801 } 1802 1803 /* 1804 * Inform hwpmc about the set of kernel modules currently loaded. 1805 */ 1806 void * 1807 linker_hwpmc_list_objects(void) 1808 { 1809 struct hwpmc_context hc; 1810 1811 hc.nmappings = 15; /* a reasonable default */ 1812 1813 retry: 1814 /* allocate nmappings+1 entries */ 1815 MALLOC(hc.kobase, struct pmckern_map_in *, 1816 (hc.nmappings + 1) * sizeof(struct pmckern_map_in), M_LINKER, 1817 M_WAITOK | M_ZERO); 1818 1819 hc.nobjects = 0; 1820 if (linker_file_foreach(linker_hwpmc_list_object, &hc) != 0) { 1821 hc.nmappings = hc.nobjects; 1822 FREE(hc.kobase, M_LINKER); 1823 goto retry; 1824 } 1825 1826 KASSERT(hc.nobjects > 0, ("linker_hpwmc_list_objects: no kernel " 1827 "objects?")); 1828 1829 /* The last entry of the malloced area comprises of all zeros. */ 1830 KASSERT(hc.kobase[hc.nobjects].pm_file == NULL, 1831 ("linker_hwpmc_list_objects: last object not NULL")); 1832 1833 return ((void *)hc.kobase); 1834 } 1835 #endif 1836 1837 /* 1838 * Find a file which contains given module and load it, if "parent" is not 1839 * NULL, register a reference to it. 1840 */ 1841 static int 1842 linker_load_module(const char *kldname, const char *modname, 1843 struct linker_file *parent, struct mod_depend *verinfo, 1844 struct linker_file **lfpp) 1845 { 1846 linker_file_t lfdep; 1847 const char *filename; 1848 char *pathname; 1849 int error; 1850 1851 KLD_LOCK_ASSERT(); 1852 if (modname == NULL) { 1853 /* 1854 * We have to load KLD 1855 */ 1856 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1857 " is not NULL")); 1858 pathname = linker_search_kld(kldname); 1859 } else { 1860 if (modlist_lookup2(modname, verinfo) != NULL) 1861 return (EEXIST); 1862 if (kldname != NULL) 1863 pathname = linker_strdup(kldname); 1864 else if (rootvnode == NULL) 1865 pathname = NULL; 1866 else 1867 /* 1868 * Need to find a KLD with required module 1869 */ 1870 pathname = linker_search_module(modname, 1871 strlen(modname), verinfo); 1872 } 1873 if (pathname == NULL) 1874 return (ENOENT); 1875 1876 /* 1877 * Can't load more than one file with the same basename XXX: 1878 * Actually it should be possible to have multiple KLDs with 1879 * the same basename but different path because they can 1880 * provide different versions of the same modules. 1881 */ 1882 filename = linker_basename(pathname); 1883 if (linker_find_file_by_name(filename)) 1884 error = EEXIST; 1885 else do { 1886 error = linker_load_file(pathname, &lfdep); 1887 if (error) 1888 break; 1889 if (modname && verinfo && 1890 modlist_lookup2(modname, verinfo) == NULL) { 1891 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1892 error = ENOENT; 1893 break; 1894 } 1895 if (parent) { 1896 error = linker_file_add_dependency(parent, lfdep); 1897 if (error) 1898 break; 1899 } 1900 if (lfpp) 1901 *lfpp = lfdep; 1902 } while (0); 1903 free(pathname, M_LINKER); 1904 return (error); 1905 } 1906 1907 /* 1908 * This routine is responsible for finding dependencies of userland initiated 1909 * kldload(2)'s of files. 1910 */ 1911 int 1912 linker_load_dependencies(linker_file_t lf) 1913 { 1914 linker_file_t lfdep; 1915 struct mod_metadata **start, **stop, **mdp, **nmdp; 1916 struct mod_metadata *mp, *nmp; 1917 struct mod_depend *verinfo; 1918 modlist_t mod; 1919 const char *modname, *nmodname; 1920 int ver, error = 0, count; 1921 1922 /* 1923 * All files are dependant on /kernel. 1924 */ 1925 KLD_LOCK_ASSERT(); 1926 if (linker_kernel_file) { 1927 linker_kernel_file->refs++; 1928 error = linker_file_add_dependency(lf, linker_kernel_file); 1929 if (error) 1930 return (error); 1931 } 1932 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1933 &count) != 0) 1934 return (0); 1935 for (mdp = start; mdp < stop; mdp++) { 1936 mp = *mdp; 1937 if (mp->md_type != MDT_VERSION) 1938 continue; 1939 modname = mp->md_cval; 1940 ver = ((struct mod_version *)mp->md_data)->mv_version; 1941 mod = modlist_lookup(modname, ver); 1942 if (mod != NULL) { 1943 printf("interface %s.%d already present in the KLD" 1944 " '%s'!\n", modname, ver, 1945 mod->container->filename); 1946 return (EEXIST); 1947 } 1948 } 1949 1950 for (mdp = start; mdp < stop; mdp++) { 1951 mp = *mdp; 1952 if (mp->md_type != MDT_DEPEND) 1953 continue; 1954 modname = mp->md_cval; 1955 verinfo = mp->md_data; 1956 nmodname = NULL; 1957 for (nmdp = start; nmdp < stop; nmdp++) { 1958 nmp = *nmdp; 1959 if (nmp->md_type != MDT_VERSION) 1960 continue; 1961 nmodname = nmp->md_cval; 1962 if (strcmp(modname, nmodname) == 0) 1963 break; 1964 } 1965 if (nmdp < stop)/* early exit, it's a self reference */ 1966 continue; 1967 mod = modlist_lookup2(modname, verinfo); 1968 if (mod) { /* woohoo, it's loaded already */ 1969 lfdep = mod->container; 1970 lfdep->refs++; 1971 error = linker_file_add_dependency(lf, lfdep); 1972 if (error) 1973 break; 1974 continue; 1975 } 1976 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1977 if (error) { 1978 printf("KLD %s: depends on %s - not available\n", 1979 lf->filename, modname); 1980 break; 1981 } 1982 } 1983 1984 if (error) 1985 return (error); 1986 linker_addmodules(lf, start, stop, 0); 1987 return (error); 1988 } 1989 1990 static int 1991 sysctl_kern_function_list_iterate(const char *name, void *opaque) 1992 { 1993 struct sysctl_req *req; 1994 1995 req = opaque; 1996 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1997 } 1998 1999 /* 2000 * Export a nul-separated, double-nul-terminated list of all function names 2001 * in the kernel. 2002 */ 2003 static int 2004 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2005 { 2006 linker_file_t lf; 2007 int error; 2008 2009 #ifdef MAC 2010 error = mac_kld_check_stat(req->td->td_ucred); 2011 if (error) 2012 return (error); 2013 #endif 2014 error = sysctl_wire_old_buffer(req, 0); 2015 if (error != 0) 2016 return (error); 2017 KLD_LOCK(); 2018 TAILQ_FOREACH(lf, &linker_files, link) { 2019 error = LINKER_EACH_FUNCTION_NAME(lf, 2020 sysctl_kern_function_list_iterate, req); 2021 if (error) { 2022 KLD_UNLOCK(); 2023 return (error); 2024 } 2025 } 2026 KLD_UNLOCK(); 2027 return (SYSCTL_OUT(req, "", 1)); 2028 } 2029 2030 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 2031 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 2032