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