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