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