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_kld.h" 32 #include "opt_hwpmc_hooks.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/eventhandler.h> 49 #include <sys/fcntl.h> 50 #include <sys/jail.h> 51 #include <sys/libkern.h> 52 #include <sys/namei.h> 53 #include <sys/vnode.h> 54 #include <sys/syscallsubr.h> 55 #include <sys/sysctl.h> 56 57 #include <net/vnet.h> 58 59 #include <security/mac/mac_framework.h> 60 61 #include "linker_if.h" 62 63 #ifdef HWPMC_HOOKS 64 #include <sys/pmckern.h> 65 #endif 66 67 #ifdef KLD_DEBUG 68 int kld_debug = 0; 69 SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RW | CTLFLAG_TUN, 70 &kld_debug, 0, "Set various levels of KLD debug"); 71 TUNABLE_INT("debug.kld_debug", &kld_debug); 72 #endif 73 74 #define KLD_LOCK() sx_xlock(&kld_sx) 75 #define KLD_UNLOCK() sx_xunlock(&kld_sx) 76 #define KLD_DOWNGRADE() sx_downgrade(&kld_sx) 77 #define KLD_LOCK_READ() sx_slock(&kld_sx) 78 #define KLD_UNLOCK_READ() sx_sunlock(&kld_sx) 79 #define KLD_LOCKED() sx_xlocked(&kld_sx) 80 #define KLD_LOCK_ASSERT() do { \ 81 if (!cold) \ 82 sx_assert(&kld_sx, SX_XLOCKED); \ 83 } while (0) 84 85 /* 86 * static char *linker_search_path(const char *name, struct mod_depend 87 * *verinfo); 88 */ 89 static const char *linker_basename(const char *path); 90 91 /* 92 * Find a currently loaded file given its filename. 93 */ 94 static linker_file_t linker_find_file_by_name(const char* _filename); 95 96 /* 97 * Find a currently loaded file given its file id. 98 */ 99 static linker_file_t linker_find_file_by_id(int _fileid); 100 101 /* Metadata from the static kernel */ 102 SET_DECLARE(modmetadata_set, struct mod_metadata); 103 104 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 105 106 linker_file_t linker_kernel_file; 107 108 static struct sx kld_sx; /* kernel linker lock */ 109 110 /* 111 * Load counter used by clients to determine if a linker file has been 112 * re-loaded. This counter is incremented for each file load. 113 */ 114 static int loadcnt; 115 116 static linker_class_list_t classes; 117 static linker_file_list_t linker_files; 118 static int next_file_id = 1; 119 static int linker_no_more_classes = 0; 120 121 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 122 linker_file_t lftmp; \ 123 \ 124 KLD_LOCK_ASSERT(); \ 125 retry: \ 126 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 127 if (next_file_id == lftmp->id) { \ 128 next_file_id++; \ 129 goto retry; \ 130 } \ 131 } \ 132 (a) = next_file_id; \ 133 } while(0) 134 135 136 /* XXX wrong name; we're looking at version provision tags here, not modules */ 137 typedef TAILQ_HEAD(, modlist) modlisthead_t; 138 struct modlist { 139 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 140 linker_file_t container; 141 const char *name; 142 int version; 143 }; 144 typedef struct modlist *modlist_t; 145 static modlisthead_t found_modules; 146 147 static int linker_file_add_dependency(linker_file_t file, 148 linker_file_t dep); 149 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file, 150 const char* name, int deps); 151 static int linker_load_module(const char *kldname, 152 const char *modname, struct linker_file *parent, 153 struct mod_depend *verinfo, struct linker_file **lfpp); 154 static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo); 155 156 static void 157 linker_init(void *arg) 158 { 159 160 sx_init(&kld_sx, "kernel linker"); 161 TAILQ_INIT(&classes); 162 TAILQ_INIT(&linker_files); 163 } 164 165 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); 166 167 static void 168 linker_stop_class_add(void *arg) 169 { 170 171 linker_no_more_classes = 1; 172 } 173 174 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL); 175 176 int 177 linker_add_class(linker_class_t lc) 178 { 179 180 /* 181 * We disallow any class registration past SI_ORDER_ANY 182 * of SI_SUB_KLD. We bump the reference count to keep the 183 * ops from being freed. 184 */ 185 if (linker_no_more_classes == 1) 186 return (EPERM); 187 kobj_class_compile((kobj_class_t) lc); 188 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 189 TAILQ_INSERT_TAIL(&classes, lc, link); 190 return (0); 191 } 192 193 static void 194 linker_file_sysinit(linker_file_t lf) 195 { 196 struct sysinit **start, **stop, **sipp, **xipp, *save; 197 198 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 199 lf->filename)); 200 201 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 202 return; 203 /* 204 * Perform a bubble sort of the system initialization objects by 205 * their subsystem (primary key) and order (secondary key). 206 * 207 * Since some things care about execution order, this is the operation 208 * which ensures continued function. 209 */ 210 for (sipp = start; sipp < stop; sipp++) { 211 for (xipp = sipp + 1; xipp < stop; xipp++) { 212 if ((*sipp)->subsystem < (*xipp)->subsystem || 213 ((*sipp)->subsystem == (*xipp)->subsystem && 214 (*sipp)->order <= (*xipp)->order)) 215 continue; /* skip */ 216 save = *sipp; 217 *sipp = *xipp; 218 *xipp = save; 219 } 220 } 221 222 /* 223 * Traverse the (now) ordered list of system initialization tasks. 224 * Perform each task, and continue on to the next task. 225 */ 226 mtx_lock(&Giant); 227 for (sipp = start; sipp < stop; sipp++) { 228 if ((*sipp)->subsystem == SI_SUB_DUMMY) 229 continue; /* skip dummy task(s) */ 230 231 /* Call function */ 232 (*((*sipp)->func)) ((*sipp)->udata); 233 } 234 mtx_unlock(&Giant); 235 } 236 237 static void 238 linker_file_sysuninit(linker_file_t lf) 239 { 240 struct sysinit **start, **stop, **sipp, **xipp, *save; 241 242 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 243 lf->filename)); 244 245 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 246 NULL) != 0) 247 return; 248 249 /* 250 * Perform a reverse bubble sort of the system initialization objects 251 * by their subsystem (primary key) and order (secondary key). 252 * 253 * Since some things care about execution order, this is the operation 254 * which ensures continued function. 255 */ 256 for (sipp = start; sipp < stop; sipp++) { 257 for (xipp = sipp + 1; xipp < stop; xipp++) { 258 if ((*sipp)->subsystem > (*xipp)->subsystem || 259 ((*sipp)->subsystem == (*xipp)->subsystem && 260 (*sipp)->order >= (*xipp)->order)) 261 continue; /* skip */ 262 save = *sipp; 263 *sipp = *xipp; 264 *xipp = save; 265 } 266 } 267 268 /* 269 * Traverse the (now) ordered list of system initialization tasks. 270 * Perform each task, and continue on to the next task. 271 */ 272 mtx_lock(&Giant); 273 for (sipp = start; sipp < stop; sipp++) { 274 if ((*sipp)->subsystem == SI_SUB_DUMMY) 275 continue; /* skip dummy task(s) */ 276 277 /* Call function */ 278 (*((*sipp)->func)) ((*sipp)->udata); 279 } 280 mtx_unlock(&Giant); 281 } 282 283 static void 284 linker_file_register_sysctls(linker_file_t lf) 285 { 286 struct sysctl_oid **start, **stop, **oidp; 287 288 KLD_DPF(FILE, 289 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 290 lf->filename)); 291 292 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 293 return; 294 295 sysctl_lock(); 296 for (oidp = start; oidp < stop; oidp++) 297 sysctl_register_oid(*oidp); 298 sysctl_unlock(); 299 } 300 301 static void 302 linker_file_unregister_sysctls(linker_file_t lf) 303 { 304 struct sysctl_oid **start, **stop, **oidp; 305 306 KLD_DPF(FILE, ("linker_file_unregister_sysctls: unregistering SYSCTLs" 307 " for %s\n", lf->filename)); 308 309 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 310 return; 311 312 sysctl_lock(); 313 for (oidp = start; oidp < stop; oidp++) 314 sysctl_unregister_oid(*oidp); 315 sysctl_unlock(); 316 } 317 318 static int 319 linker_file_register_modules(linker_file_t lf) 320 { 321 struct mod_metadata **start, **stop, **mdp; 322 const moduledata_t *moddata; 323 int first_error, error; 324 325 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 326 " in %s\n", lf->filename)); 327 328 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 329 &stop, NULL) != 0) { 330 /* 331 * This fallback should be unnecessary, but if we get booted 332 * from boot2 instead of loader and we are missing our 333 * metadata then we have to try the best we can. 334 */ 335 if (lf == linker_kernel_file) { 336 start = SET_BEGIN(modmetadata_set); 337 stop = SET_LIMIT(modmetadata_set); 338 } else 339 return (0); 340 } 341 first_error = 0; 342 for (mdp = start; mdp < stop; mdp++) { 343 if ((*mdp)->md_type != MDT_MODULE) 344 continue; 345 moddata = (*mdp)->md_data; 346 KLD_DPF(FILE, ("Registering module %s in %s\n", 347 moddata->name, lf->filename)); 348 error = module_register(moddata, lf); 349 if (error) { 350 printf("Module %s failed to register: %d\n", 351 moddata->name, error); 352 if (first_error == 0) 353 first_error = error; 354 } 355 } 356 return (first_error); 357 } 358 359 static void 360 linker_init_kernel_modules(void) 361 { 362 363 linker_file_register_modules(linker_kernel_file); 364 } 365 366 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 367 0); 368 369 static int 370 linker_load_file(const char *filename, linker_file_t *result) 371 { 372 linker_class_t lc; 373 linker_file_t lf; 374 int foundfile, error, modules; 375 376 /* Refuse to load modules if securelevel raised */ 377 if (prison0.pr_securelevel > 0) 378 return (EPERM); 379 380 KLD_LOCK_ASSERT(); 381 lf = linker_find_file_by_name(filename); 382 if (lf) { 383 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 384 " incrementing refs\n", filename)); 385 *result = lf; 386 lf->refs++; 387 return (0); 388 } 389 foundfile = 0; 390 error = 0; 391 392 /* 393 * We do not need to protect (lock) classes here because there is 394 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 395 * and there is no class deregistration mechanism at this time. 396 */ 397 TAILQ_FOREACH(lc, &classes, link) { 398 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 399 filename)); 400 error = LINKER_LOAD_FILE(lc, filename, &lf); 401 /* 402 * If we got something other than ENOENT, then it exists but 403 * we cannot load it for some other reason. 404 */ 405 if (error != ENOENT) 406 foundfile = 1; 407 if (lf) { 408 error = linker_file_register_modules(lf); 409 if (error == EEXIST) { 410 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 411 return (error); 412 } 413 modules = !TAILQ_EMPTY(&lf->modules); 414 KLD_UNLOCK(); 415 linker_file_register_sysctls(lf); 416 linker_file_sysinit(lf); 417 KLD_LOCK(); 418 lf->flags |= LINKER_FILE_LINKED; 419 420 /* 421 * If all of the modules in this file failed 422 * to load, unload the file and return an 423 * error of ENOEXEC. 424 */ 425 if (modules && TAILQ_EMPTY(&lf->modules)) { 426 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 427 return (ENOEXEC); 428 } 429 *result = lf; 430 return (0); 431 } 432 } 433 /* 434 * Less than ideal, but tells the user whether it failed to load or 435 * the module was not found. 436 */ 437 if (foundfile) { 438 439 /* 440 * If the file type has not been recognized by the last try 441 * printout a message before to fail. 442 */ 443 if (error == ENOSYS) 444 printf("linker_load_file: Unsupported file type\n"); 445 446 /* 447 * Format not recognized or otherwise unloadable. 448 * When loading a module that is statically built into 449 * the kernel EEXIST percolates back up as the return 450 * value. Preserve this so that apps like sysinstall 451 * can recognize this special case and not post bogus 452 * dialog boxes. 453 */ 454 if (error != EEXIST) 455 error = ENOEXEC; 456 } else 457 error = ENOENT; /* Nothing found */ 458 return (error); 459 } 460 461 int 462 linker_reference_module(const char *modname, struct mod_depend *verinfo, 463 linker_file_t *result) 464 { 465 modlist_t mod; 466 int error; 467 468 KLD_LOCK(); 469 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 470 *result = mod->container; 471 (*result)->refs++; 472 KLD_UNLOCK(); 473 return (0); 474 } 475 476 error = linker_load_module(NULL, modname, NULL, verinfo, result); 477 KLD_UNLOCK(); 478 return (error); 479 } 480 481 int 482 linker_release_module(const char *modname, struct mod_depend *verinfo, 483 linker_file_t lf) 484 { 485 modlist_t mod; 486 int error; 487 488 KLD_LOCK(); 489 if (lf == NULL) { 490 KASSERT(modname != NULL, 491 ("linker_release_module: no file or name")); 492 mod = modlist_lookup2(modname, verinfo); 493 if (mod == NULL) { 494 KLD_UNLOCK(); 495 return (ESRCH); 496 } 497 lf = mod->container; 498 } else 499 KASSERT(modname == NULL && verinfo == NULL, 500 ("linker_release_module: both file and name")); 501 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 502 KLD_UNLOCK(); 503 return (error); 504 } 505 506 static linker_file_t 507 linker_find_file_by_name(const char *filename) 508 { 509 linker_file_t lf; 510 char *koname; 511 512 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 513 sprintf(koname, "%s.ko", filename); 514 515 KLD_LOCK_ASSERT(); 516 TAILQ_FOREACH(lf, &linker_files, link) { 517 if (strcmp(lf->filename, koname) == 0) 518 break; 519 if (strcmp(lf->filename, filename) == 0) 520 break; 521 } 522 free(koname, M_LINKER); 523 return (lf); 524 } 525 526 static linker_file_t 527 linker_find_file_by_id(int fileid) 528 { 529 linker_file_t lf; 530 531 KLD_LOCK_ASSERT(); 532 TAILQ_FOREACH(lf, &linker_files, link) 533 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 534 break; 535 return (lf); 536 } 537 538 int 539 linker_file_foreach(linker_predicate_t *predicate, void *context) 540 { 541 linker_file_t lf; 542 int retval = 0; 543 544 KLD_LOCK(); 545 TAILQ_FOREACH(lf, &linker_files, link) { 546 retval = predicate(lf, context); 547 if (retval != 0) 548 break; 549 } 550 KLD_UNLOCK(); 551 return (retval); 552 } 553 554 linker_file_t 555 linker_make_file(const char *pathname, linker_class_t lc) 556 { 557 linker_file_t lf; 558 const char *filename; 559 560 KLD_LOCK_ASSERT(); 561 filename = linker_basename(pathname); 562 563 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 564 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 565 if (lf == NULL) 566 return (NULL); 567 lf->refs = 1; 568 lf->userrefs = 0; 569 lf->flags = 0; 570 lf->filename = strdup(filename, M_LINKER); 571 lf->pathname = strdup(pathname, M_LINKER); 572 LINKER_GET_NEXT_FILE_ID(lf->id); 573 lf->ndeps = 0; 574 lf->deps = NULL; 575 lf->loadcnt = ++loadcnt; 576 STAILQ_INIT(&lf->common); 577 TAILQ_INIT(&lf->modules); 578 TAILQ_INSERT_TAIL(&linker_files, lf, link); 579 return (lf); 580 } 581 582 int 583 linker_file_unload(linker_file_t file, int flags) 584 { 585 module_t mod, next; 586 modlist_t ml, nextml; 587 struct common_symbol *cp; 588 int error, i; 589 590 /* Refuse to unload modules if securelevel raised. */ 591 if (prison0.pr_securelevel > 0) 592 return (EPERM); 593 594 KLD_LOCK_ASSERT(); 595 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 596 597 /* Easy case of just dropping a reference. */ 598 if (file->refs > 1) { 599 file->refs--; 600 return (0); 601 } 602 603 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 604 " informing modules\n")); 605 606 /* 607 * Quiesce all the modules to give them a chance to veto the unload. 608 */ 609 MOD_SLOCK; 610 for (mod = TAILQ_FIRST(&file->modules); mod; 611 mod = module_getfnext(mod)) { 612 613 error = module_quiesce(mod); 614 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 615 KLD_DPF(FILE, ("linker_file_unload: module %s" 616 " vetoed unload\n", module_getname(mod))); 617 /* 618 * XXX: Do we need to tell all the quiesced modules 619 * that they can resume work now via a new module 620 * event? 621 */ 622 MOD_SUNLOCK; 623 return (error); 624 } 625 } 626 MOD_SUNLOCK; 627 628 /* 629 * Inform any modules associated with this file that they are 630 * being unloaded. 631 */ 632 MOD_XLOCK; 633 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 634 next = module_getfnext(mod); 635 MOD_XUNLOCK; 636 637 /* 638 * Give the module a chance to veto the unload. 639 */ 640 if ((error = module_unload(mod)) != 0) { 641 #ifdef KLD_DEBUG 642 MOD_SLOCK; 643 KLD_DPF(FILE, ("linker_file_unload: module %s" 644 " failed unload\n", module_getname(mod))); 645 MOD_SUNLOCK; 646 #endif 647 return (error); 648 } 649 MOD_XLOCK; 650 module_release(mod); 651 } 652 MOD_XUNLOCK; 653 654 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 655 if (ml->container == file) { 656 TAILQ_REMOVE(&found_modules, ml, link); 657 free(ml, M_LINKER); 658 } 659 } 660 661 /* 662 * Don't try to run SYSUNINITs if we are unloaded due to a 663 * link error. 664 */ 665 if (file->flags & LINKER_FILE_LINKED) { 666 file->flags &= ~LINKER_FILE_LINKED; 667 KLD_UNLOCK(); 668 linker_file_sysuninit(file); 669 linker_file_unregister_sysctls(file); 670 KLD_LOCK(); 671 } 672 TAILQ_REMOVE(&linker_files, file, link); 673 674 if (file->deps) { 675 for (i = 0; i < file->ndeps; i++) 676 linker_file_unload(file->deps[i], flags); 677 free(file->deps, M_LINKER); 678 file->deps = NULL; 679 } 680 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 681 STAILQ_REMOVE_HEAD(&file->common, link); 682 free(cp, M_LINKER); 683 } 684 685 LINKER_UNLOAD(file); 686 if (file->filename) { 687 free(file->filename, M_LINKER); 688 file->filename = NULL; 689 } 690 if (file->pathname) { 691 free(file->pathname, M_LINKER); 692 file->pathname = NULL; 693 } 694 kobj_delete((kobj_t) file, M_LINKER); 695 return (0); 696 } 697 698 int 699 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 700 { 701 return (LINKER_CTF_GET(file, lc)); 702 } 703 704 static int 705 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 706 { 707 linker_file_t *newdeps; 708 709 KLD_LOCK_ASSERT(); 710 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 711 M_LINKER, M_WAITOK | M_ZERO); 712 if (newdeps == NULL) 713 return (ENOMEM); 714 715 if (file->deps) { 716 bcopy(file->deps, newdeps, 717 file->ndeps * sizeof(linker_file_t *)); 718 free(file->deps, M_LINKER); 719 } 720 file->deps = newdeps; 721 file->deps[file->ndeps] = dep; 722 file->ndeps++; 723 KLD_DPF(FILE, ("linker_file_add_dependency:" 724 " adding %s as dependency for %s\n", 725 dep->filename, file->filename)); 726 return (0); 727 } 728 729 /* 730 * Locate a linker set and its contents. This is a helper function to avoid 731 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 732 * This function is used in this file so we can avoid having lots of (void **) 733 * casts. 734 */ 735 int 736 linker_file_lookup_set(linker_file_t file, const char *name, 737 void *firstp, void *lastp, int *countp) 738 { 739 int error, locked; 740 741 locked = KLD_LOCKED(); 742 if (!locked) 743 KLD_LOCK(); 744 error = LINKER_LOOKUP_SET(file, name, firstp, lastp, countp); 745 if (!locked) 746 KLD_UNLOCK(); 747 return (error); 748 } 749 750 /* 751 * List all functions in a file. 752 */ 753 int 754 linker_file_function_listall(linker_file_t lf, 755 linker_function_nameval_callback_t callback_func, void *arg) 756 { 757 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 758 } 759 760 caddr_t 761 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 762 { 763 caddr_t sym; 764 int locked; 765 766 locked = KLD_LOCKED(); 767 if (!locked) 768 KLD_LOCK(); 769 sym = linker_file_lookup_symbol_internal(file, name, deps); 770 if (!locked) 771 KLD_UNLOCK(); 772 return (sym); 773 } 774 775 static caddr_t 776 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 777 int deps) 778 { 779 c_linker_sym_t sym; 780 linker_symval_t symval; 781 caddr_t address; 782 size_t common_size = 0; 783 int i; 784 785 KLD_LOCK_ASSERT(); 786 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 787 file, name, deps)); 788 789 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 790 LINKER_SYMBOL_VALUES(file, sym, &symval); 791 if (symval.value == 0) 792 /* 793 * For commons, first look them up in the 794 * dependencies and only allocate space if not found 795 * there. 796 */ 797 common_size = symval.size; 798 else { 799 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 800 ".value=%p\n", symval.value)); 801 return (symval.value); 802 } 803 } 804 if (deps) { 805 for (i = 0; i < file->ndeps; i++) { 806 address = linker_file_lookup_symbol_internal( 807 file->deps[i], name, 0); 808 if (address) { 809 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 810 " deps value=%p\n", address)); 811 return (address); 812 } 813 } 814 } 815 if (common_size > 0) { 816 /* 817 * This is a common symbol which was not found in the 818 * dependencies. We maintain a simple common symbol table in 819 * the file object. 820 */ 821 struct common_symbol *cp; 822 823 STAILQ_FOREACH(cp, &file->common, link) { 824 if (strcmp(cp->name, name) == 0) { 825 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 826 " old common value=%p\n", cp->address)); 827 return (cp->address); 828 } 829 } 830 /* 831 * Round the symbol size up to align. 832 */ 833 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 834 cp = malloc(sizeof(struct common_symbol) 835 + common_size + strlen(name) + 1, M_LINKER, 836 M_WAITOK | M_ZERO); 837 cp->address = (caddr_t)(cp + 1); 838 cp->name = cp->address + common_size; 839 strcpy(cp->name, name); 840 bzero(cp->address, common_size); 841 STAILQ_INSERT_TAIL(&file->common, cp, link); 842 843 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 844 " value=%p\n", cp->address)); 845 return (cp->address); 846 } 847 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 848 return (0); 849 } 850 851 /* 852 * Both DDB and stack(9) rely on the kernel linker to provide forward and 853 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 854 * do this in a lockfree manner. We provide a set of internal helper 855 * routines to perform these operations without locks, and then wrappers that 856 * optionally lock. 857 * 858 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 859 */ 860 #ifdef DDB 861 static int 862 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 863 { 864 linker_file_t lf; 865 866 TAILQ_FOREACH(lf, &linker_files, link) { 867 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 868 return (0); 869 } 870 return (ENOENT); 871 } 872 #endif 873 874 static int 875 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 876 { 877 linker_file_t lf; 878 c_linker_sym_t best, es; 879 u_long diff, bestdiff, off; 880 881 best = 0; 882 off = (uintptr_t)value; 883 bestdiff = off; 884 TAILQ_FOREACH(lf, &linker_files, link) { 885 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 886 continue; 887 if (es != 0 && diff < bestdiff) { 888 best = es; 889 bestdiff = diff; 890 } 891 if (bestdiff == 0) 892 break; 893 } 894 if (best) { 895 *sym = best; 896 *diffp = bestdiff; 897 return (0); 898 } else { 899 *sym = 0; 900 *diffp = off; 901 return (ENOENT); 902 } 903 } 904 905 static int 906 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 907 { 908 linker_file_t lf; 909 910 TAILQ_FOREACH(lf, &linker_files, link) { 911 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 912 return (0); 913 } 914 return (ENOENT); 915 } 916 917 static int 918 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 919 long *offset) 920 { 921 linker_symval_t symval; 922 c_linker_sym_t sym; 923 int error; 924 925 *offset = 0; 926 error = linker_debug_search_symbol(value, &sym, offset); 927 if (error) 928 return (error); 929 error = linker_debug_symbol_values(sym, &symval); 930 if (error) 931 return (error); 932 strlcpy(buf, symval.name, buflen); 933 return (0); 934 } 935 936 /* 937 * DDB Helpers. DDB has to look across multiple files with their own symbol 938 * tables and string tables. 939 * 940 * Note that we do not obey list locking protocols here. We really don't need 941 * DDB to hang because somebody's got the lock held. We'll take the chance 942 * that the files list is inconsistant instead. 943 */ 944 #ifdef DDB 945 int 946 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 947 { 948 949 return (linker_debug_lookup(symstr, sym)); 950 } 951 #endif 952 953 int 954 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 955 { 956 957 return (linker_debug_search_symbol(value, sym, diffp)); 958 } 959 960 int 961 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 962 { 963 964 return (linker_debug_symbol_values(sym, symval)); 965 } 966 967 int 968 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 969 long *offset) 970 { 971 972 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 973 } 974 975 /* 976 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 977 * obey locking protocols, and offer a significantly less complex interface. 978 */ 979 int 980 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 981 long *offset) 982 { 983 int error; 984 985 KLD_LOCK(); 986 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 987 KLD_UNLOCK(); 988 return (error); 989 } 990 991 /* 992 * Syscalls. 993 */ 994 int 995 kern_kldload(struct thread *td, const char *file, int *fileid) 996 { 997 #ifdef HWPMC_HOOKS 998 struct pmckern_map_in pkm; 999 #endif 1000 const char *kldname, *modname; 1001 linker_file_t lf; 1002 int error; 1003 1004 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1005 return (error); 1006 1007 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1008 return (error); 1009 1010 /* 1011 * It is possible that kldloaded module will attach a new ifnet, 1012 * so vnet context must be set when this ocurs. 1013 */ 1014 CURVNET_SET(TD_TO_VNET(td)); 1015 1016 /* 1017 * If file does not contain a qualified name or any dot in it 1018 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1019 * name. 1020 */ 1021 if (strchr(file, '/') || strchr(file, '.')) { 1022 kldname = file; 1023 modname = NULL; 1024 } else { 1025 kldname = NULL; 1026 modname = file; 1027 } 1028 1029 KLD_LOCK(); 1030 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1031 if (error) { 1032 KLD_UNLOCK(); 1033 goto done; 1034 } 1035 lf->userrefs++; 1036 if (fileid != NULL) 1037 *fileid = lf->id; 1038 1039 EVENTHANDLER_INVOKE(kld_load, lf); 1040 1041 #ifdef HWPMC_HOOKS 1042 KLD_DOWNGRADE(); 1043 pkm.pm_file = lf->filename; 1044 pkm.pm_address = (uintptr_t) lf->address; 1045 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 1046 KLD_UNLOCK_READ(); 1047 #else 1048 KLD_UNLOCK(); 1049 #endif 1050 1051 done: 1052 CURVNET_RESTORE(); 1053 return (error); 1054 } 1055 1056 int 1057 sys_kldload(struct thread *td, struct kldload_args *uap) 1058 { 1059 char *pathname = NULL; 1060 int error, fileid; 1061 1062 td->td_retval[0] = -1; 1063 1064 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1065 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1066 if (error == 0) { 1067 error = kern_kldload(td, pathname, &fileid); 1068 if (error == 0) 1069 td->td_retval[0] = fileid; 1070 } 1071 free(pathname, M_TEMP); 1072 return (error); 1073 } 1074 1075 int 1076 kern_kldunload(struct thread *td, int fileid, int flags) 1077 { 1078 #ifdef HWPMC_HOOKS 1079 struct pmckern_map_out pkm; 1080 #endif 1081 linker_file_t lf; 1082 int error = 0; 1083 1084 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1085 return (error); 1086 1087 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1088 return (error); 1089 1090 CURVNET_SET(TD_TO_VNET(td)); 1091 KLD_LOCK(); 1092 lf = linker_find_file_by_id(fileid); 1093 if (lf) { 1094 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1095 1096 EVENTHANDLER_INVOKE(kld_unload, lf, &error); 1097 if (error != 0) 1098 error = EBUSY; 1099 else if (lf->userrefs == 0) { 1100 /* 1101 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1102 */ 1103 printf("kldunload: attempt to unload file that was" 1104 " loaded by the kernel\n"); 1105 error = EBUSY; 1106 } else { 1107 #ifdef HWPMC_HOOKS 1108 /* Save data needed by hwpmc(4) before unloading. */ 1109 pkm.pm_address = (uintptr_t) lf->address; 1110 pkm.pm_size = lf->size; 1111 #endif 1112 lf->userrefs--; 1113 error = linker_file_unload(lf, flags); 1114 if (error) 1115 lf->userrefs++; 1116 } 1117 } else 1118 error = ENOENT; 1119 1120 #ifdef HWPMC_HOOKS 1121 if (error == 0) { 1122 KLD_DOWNGRADE(); 1123 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 1124 KLD_UNLOCK_READ(); 1125 } else 1126 KLD_UNLOCK(); 1127 #else 1128 KLD_UNLOCK(); 1129 #endif 1130 CURVNET_RESTORE(); 1131 return (error); 1132 } 1133 1134 int 1135 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1136 { 1137 1138 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1139 } 1140 1141 int 1142 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1143 { 1144 1145 if (uap->flags != LINKER_UNLOAD_NORMAL && 1146 uap->flags != LINKER_UNLOAD_FORCE) 1147 return (EINVAL); 1148 return (kern_kldunload(td, uap->fileid, uap->flags)); 1149 } 1150 1151 int 1152 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1153 { 1154 char *pathname; 1155 const char *filename; 1156 linker_file_t lf; 1157 int error; 1158 1159 #ifdef MAC 1160 error = mac_kld_check_stat(td->td_ucred); 1161 if (error) 1162 return (error); 1163 #endif 1164 1165 td->td_retval[0] = -1; 1166 1167 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1168 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1169 goto out; 1170 1171 filename = linker_basename(pathname); 1172 KLD_LOCK(); 1173 lf = linker_find_file_by_name(filename); 1174 if (lf) 1175 td->td_retval[0] = lf->id; 1176 else 1177 error = ENOENT; 1178 KLD_UNLOCK(); 1179 out: 1180 free(pathname, M_TEMP); 1181 return (error); 1182 } 1183 1184 int 1185 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1186 { 1187 linker_file_t lf; 1188 int error = 0; 1189 1190 #ifdef MAC 1191 error = mac_kld_check_stat(td->td_ucred); 1192 if (error) 1193 return (error); 1194 #endif 1195 1196 KLD_LOCK(); 1197 if (uap->fileid == 0) 1198 lf = TAILQ_FIRST(&linker_files); 1199 else { 1200 lf = linker_find_file_by_id(uap->fileid); 1201 if (lf == NULL) { 1202 error = ENOENT; 1203 goto out; 1204 } 1205 lf = TAILQ_NEXT(lf, link); 1206 } 1207 1208 /* Skip partially loaded files. */ 1209 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1210 lf = TAILQ_NEXT(lf, link); 1211 1212 if (lf) 1213 td->td_retval[0] = lf->id; 1214 else 1215 td->td_retval[0] = 0; 1216 out: 1217 KLD_UNLOCK(); 1218 return (error); 1219 } 1220 1221 int 1222 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1223 { 1224 struct kld_file_stat stat; 1225 int error, version; 1226 1227 /* 1228 * Check the version of the user's structure. 1229 */ 1230 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1231 != 0) 1232 return (error); 1233 if (version != sizeof(struct kld_file_stat_1) && 1234 version != sizeof(struct kld_file_stat)) 1235 return (EINVAL); 1236 1237 error = kern_kldstat(td, uap->fileid, &stat); 1238 if (error != 0) 1239 return (error); 1240 return (copyout(&stat, uap->stat, version)); 1241 } 1242 1243 int 1244 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1245 { 1246 linker_file_t lf; 1247 int namelen; 1248 #ifdef MAC 1249 int error; 1250 1251 error = mac_kld_check_stat(td->td_ucred); 1252 if (error) 1253 return (error); 1254 #endif 1255 1256 KLD_LOCK(); 1257 lf = linker_find_file_by_id(fileid); 1258 if (lf == NULL) { 1259 KLD_UNLOCK(); 1260 return (ENOENT); 1261 } 1262 1263 /* Version 1 fields: */ 1264 namelen = strlen(lf->filename) + 1; 1265 if (namelen > MAXPATHLEN) 1266 namelen = MAXPATHLEN; 1267 bcopy(lf->filename, &stat->name[0], namelen); 1268 stat->refs = lf->refs; 1269 stat->id = lf->id; 1270 stat->address = lf->address; 1271 stat->size = lf->size; 1272 /* Version 2 fields: */ 1273 namelen = strlen(lf->pathname) + 1; 1274 if (namelen > MAXPATHLEN) 1275 namelen = MAXPATHLEN; 1276 bcopy(lf->pathname, &stat->pathname[0], namelen); 1277 KLD_UNLOCK(); 1278 1279 td->td_retval[0] = 0; 1280 return (0); 1281 } 1282 1283 int 1284 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1285 { 1286 linker_file_t lf; 1287 module_t mp; 1288 int error = 0; 1289 1290 #ifdef MAC 1291 error = mac_kld_check_stat(td->td_ucred); 1292 if (error) 1293 return (error); 1294 #endif 1295 1296 KLD_LOCK(); 1297 lf = linker_find_file_by_id(uap->fileid); 1298 if (lf) { 1299 MOD_SLOCK; 1300 mp = TAILQ_FIRST(&lf->modules); 1301 if (mp != NULL) 1302 td->td_retval[0] = module_getid(mp); 1303 else 1304 td->td_retval[0] = 0; 1305 MOD_SUNLOCK; 1306 } else 1307 error = ENOENT; 1308 KLD_UNLOCK(); 1309 return (error); 1310 } 1311 1312 int 1313 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1314 { 1315 char *symstr = NULL; 1316 c_linker_sym_t sym; 1317 linker_symval_t symval; 1318 linker_file_t lf; 1319 struct kld_sym_lookup lookup; 1320 int error = 0; 1321 1322 #ifdef MAC 1323 error = mac_kld_check_stat(td->td_ucred); 1324 if (error) 1325 return (error); 1326 #endif 1327 1328 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1329 return (error); 1330 if (lookup.version != sizeof(lookup) || 1331 uap->cmd != KLDSYM_LOOKUP) 1332 return (EINVAL); 1333 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1334 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1335 goto out; 1336 KLD_LOCK(); 1337 if (uap->fileid != 0) { 1338 lf = linker_find_file_by_id(uap->fileid); 1339 if (lf == NULL) 1340 error = ENOENT; 1341 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1342 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1343 lookup.symvalue = (uintptr_t) symval.value; 1344 lookup.symsize = symval.size; 1345 error = copyout(&lookup, uap->data, sizeof(lookup)); 1346 } else 1347 error = ENOENT; 1348 } else { 1349 TAILQ_FOREACH(lf, &linker_files, link) { 1350 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1351 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1352 lookup.symvalue = (uintptr_t)symval.value; 1353 lookup.symsize = symval.size; 1354 error = copyout(&lookup, uap->data, 1355 sizeof(lookup)); 1356 break; 1357 } 1358 } 1359 if (lf == NULL) 1360 error = ENOENT; 1361 } 1362 KLD_UNLOCK(); 1363 out: 1364 free(symstr, M_TEMP); 1365 return (error); 1366 } 1367 1368 /* 1369 * Preloaded module support 1370 */ 1371 1372 static modlist_t 1373 modlist_lookup(const char *name, int ver) 1374 { 1375 modlist_t mod; 1376 1377 TAILQ_FOREACH(mod, &found_modules, link) { 1378 if (strcmp(mod->name, name) == 0 && 1379 (ver == 0 || mod->version == ver)) 1380 return (mod); 1381 } 1382 return (NULL); 1383 } 1384 1385 static modlist_t 1386 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1387 { 1388 modlist_t mod, bestmod; 1389 int ver; 1390 1391 if (verinfo == NULL) 1392 return (modlist_lookup(name, 0)); 1393 bestmod = NULL; 1394 TAILQ_FOREACH(mod, &found_modules, link) { 1395 if (strcmp(mod->name, name) != 0) 1396 continue; 1397 ver = mod->version; 1398 if (ver == verinfo->md_ver_preferred) 1399 return (mod); 1400 if (ver >= verinfo->md_ver_minimum && 1401 ver <= verinfo->md_ver_maximum && 1402 (bestmod == NULL || ver > bestmod->version)) 1403 bestmod = mod; 1404 } 1405 return (bestmod); 1406 } 1407 1408 static modlist_t 1409 modlist_newmodule(const char *modname, int version, linker_file_t container) 1410 { 1411 modlist_t mod; 1412 1413 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1414 if (mod == NULL) 1415 panic("no memory for module list"); 1416 mod->container = container; 1417 mod->name = modname; 1418 mod->version = version; 1419 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1420 return (mod); 1421 } 1422 1423 static void 1424 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1425 struct mod_metadata **stop, int preload) 1426 { 1427 struct mod_metadata *mp, **mdp; 1428 const char *modname; 1429 int ver; 1430 1431 for (mdp = start; mdp < stop; mdp++) { 1432 mp = *mdp; 1433 if (mp->md_type != MDT_VERSION) 1434 continue; 1435 modname = mp->md_cval; 1436 ver = ((struct mod_version *)mp->md_data)->mv_version; 1437 if (modlist_lookup(modname, ver) != NULL) { 1438 printf("module %s already present!\n", modname); 1439 /* XXX what can we do? this is a build error. :-( */ 1440 continue; 1441 } 1442 modlist_newmodule(modname, ver, lf); 1443 } 1444 } 1445 1446 static void 1447 linker_preload(void *arg) 1448 { 1449 caddr_t modptr; 1450 const char *modname, *nmodname; 1451 char *modtype; 1452 linker_file_t lf, nlf; 1453 linker_class_t lc; 1454 int error; 1455 linker_file_list_t loaded_files; 1456 linker_file_list_t depended_files; 1457 struct mod_metadata *mp, *nmp; 1458 struct mod_metadata **start, **stop, **mdp, **nmdp; 1459 struct mod_depend *verinfo; 1460 int nver; 1461 int resolves; 1462 modlist_t mod; 1463 struct sysinit **si_start, **si_stop; 1464 1465 TAILQ_INIT(&loaded_files); 1466 TAILQ_INIT(&depended_files); 1467 TAILQ_INIT(&found_modules); 1468 error = 0; 1469 1470 modptr = NULL; 1471 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1472 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1473 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1474 if (modname == NULL) { 1475 printf("Preloaded module at %p does not have a" 1476 " name!\n", modptr); 1477 continue; 1478 } 1479 if (modtype == NULL) { 1480 printf("Preloaded module at %p does not have a type!\n", 1481 modptr); 1482 continue; 1483 } 1484 if (bootverbose) 1485 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1486 modptr); 1487 lf = NULL; 1488 TAILQ_FOREACH(lc, &classes, link) { 1489 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1490 if (!error) 1491 break; 1492 lf = NULL; 1493 } 1494 if (lf) 1495 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1496 } 1497 1498 /* 1499 * First get a list of stuff in the kernel. 1500 */ 1501 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1502 &stop, NULL) == 0) 1503 linker_addmodules(linker_kernel_file, start, stop, 1); 1504 1505 /* 1506 * This is a once-off kinky bubble sort to resolve relocation 1507 * dependency requirements. 1508 */ 1509 restart: 1510 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1511 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1512 &stop, NULL); 1513 /* 1514 * First, look to see if we would successfully link with this 1515 * stuff. 1516 */ 1517 resolves = 1; /* unless we know otherwise */ 1518 if (!error) { 1519 for (mdp = start; mdp < stop; mdp++) { 1520 mp = *mdp; 1521 if (mp->md_type != MDT_DEPEND) 1522 continue; 1523 modname = mp->md_cval; 1524 verinfo = mp->md_data; 1525 for (nmdp = start; nmdp < stop; nmdp++) { 1526 nmp = *nmdp; 1527 if (nmp->md_type != MDT_VERSION) 1528 continue; 1529 nmodname = nmp->md_cval; 1530 if (strcmp(modname, nmodname) == 0) 1531 break; 1532 } 1533 if (nmdp < stop) /* it's a self reference */ 1534 continue; 1535 1536 /* 1537 * ok, the module isn't here yet, we 1538 * are not finished 1539 */ 1540 if (modlist_lookup2(modname, verinfo) == NULL) 1541 resolves = 0; 1542 } 1543 } 1544 /* 1545 * OK, if we found our modules, we can link. So, "provide" 1546 * the modules inside and add it to the end of the link order 1547 * list. 1548 */ 1549 if (resolves) { 1550 if (!error) { 1551 for (mdp = start; mdp < stop; mdp++) { 1552 mp = *mdp; 1553 if (mp->md_type != MDT_VERSION) 1554 continue; 1555 modname = mp->md_cval; 1556 nver = ((struct mod_version *) 1557 mp->md_data)->mv_version; 1558 if (modlist_lookup(modname, 1559 nver) != NULL) { 1560 printf("module %s already" 1561 " present!\n", modname); 1562 TAILQ_REMOVE(&loaded_files, 1563 lf, loaded); 1564 linker_file_unload(lf, 1565 LINKER_UNLOAD_FORCE); 1566 /* we changed tailq next ptr */ 1567 goto restart; 1568 } 1569 modlist_newmodule(modname, nver, lf); 1570 } 1571 } 1572 TAILQ_REMOVE(&loaded_files, lf, loaded); 1573 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1574 /* 1575 * Since we provided modules, we need to restart the 1576 * sort so that the previous files that depend on us 1577 * have a chance. Also, we've busted the tailq next 1578 * pointer with the REMOVE. 1579 */ 1580 goto restart; 1581 } 1582 } 1583 1584 /* 1585 * At this point, we check to see what could not be resolved.. 1586 */ 1587 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1588 TAILQ_REMOVE(&loaded_files, lf, loaded); 1589 printf("KLD file %s is missing dependencies\n", lf->filename); 1590 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1591 } 1592 1593 /* 1594 * We made it. Finish off the linking in the order we determined. 1595 */ 1596 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1597 if (linker_kernel_file) { 1598 linker_kernel_file->refs++; 1599 error = linker_file_add_dependency(lf, 1600 linker_kernel_file); 1601 if (error) 1602 panic("cannot add dependency"); 1603 } 1604 lf->userrefs++; /* so we can (try to) kldunload it */ 1605 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1606 &stop, NULL); 1607 if (!error) { 1608 for (mdp = start; mdp < stop; mdp++) { 1609 mp = *mdp; 1610 if (mp->md_type != MDT_DEPEND) 1611 continue; 1612 modname = mp->md_cval; 1613 verinfo = mp->md_data; 1614 mod = modlist_lookup2(modname, verinfo); 1615 if (mod == NULL) { 1616 printf("KLD file %s - cannot find " 1617 "dependency \"%s\"\n", 1618 lf->filename, modname); 1619 goto fail; 1620 } 1621 /* Don't count self-dependencies */ 1622 if (lf == mod->container) 1623 continue; 1624 mod->container->refs++; 1625 error = linker_file_add_dependency(lf, 1626 mod->container); 1627 if (error) 1628 panic("cannot add dependency"); 1629 } 1630 } 1631 /* 1632 * Now do relocation etc using the symbol search paths 1633 * established by the dependencies 1634 */ 1635 error = LINKER_LINK_PRELOAD_FINISH(lf); 1636 if (error) { 1637 printf("KLD file %s - could not finalize loading\n", 1638 lf->filename); 1639 goto fail; 1640 } 1641 linker_file_register_modules(lf); 1642 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1643 &si_stop, NULL) == 0) 1644 sysinit_add(si_start, si_stop); 1645 linker_file_register_sysctls(lf); 1646 lf->flags |= LINKER_FILE_LINKED; 1647 continue; 1648 fail: 1649 TAILQ_REMOVE(&depended_files, lf, loaded); 1650 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1651 } 1652 /* woohoo! we made it! */ 1653 } 1654 1655 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1656 1657 /* 1658 * Search for a not-loaded module by name. 1659 * 1660 * Modules may be found in the following locations: 1661 * 1662 * - preloaded (result is just the module name) - on disk (result is full path 1663 * to module) 1664 * 1665 * If the module name is qualified in any way (contains path, etc.) the we 1666 * simply return a copy of it. 1667 * 1668 * The search path can be manipulated via sysctl. Note that we use the ';' 1669 * character as a separator to be consistent with the bootloader. 1670 */ 1671 1672 static char linker_hintfile[] = "linker.hints"; 1673 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1674 1675 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1676 sizeof(linker_path), "module load search path"); 1677 1678 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1679 1680 static char *linker_ext_list[] = { 1681 "", 1682 ".ko", 1683 NULL 1684 }; 1685 1686 /* 1687 * Check if file actually exists either with or without extension listed in 1688 * the linker_ext_list. (probably should be generic for the rest of the 1689 * kernel) 1690 */ 1691 static char * 1692 linker_lookup_file(const char *path, int pathlen, const char *name, 1693 int namelen, struct vattr *vap) 1694 { 1695 struct nameidata nd; 1696 struct thread *td = curthread; /* XXX */ 1697 char *result, **cpp, *sep; 1698 int error, len, extlen, reclen, flags; 1699 enum vtype type; 1700 1701 extlen = 0; 1702 for (cpp = linker_ext_list; *cpp; cpp++) { 1703 len = strlen(*cpp); 1704 if (len > extlen) 1705 extlen = len; 1706 } 1707 extlen++; /* trailing '\0' */ 1708 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1709 1710 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1711 result = malloc(reclen, M_LINKER, M_WAITOK); 1712 for (cpp = linker_ext_list; *cpp; cpp++) { 1713 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1714 namelen, name, *cpp); 1715 /* 1716 * Attempt to open the file, and return the path if 1717 * we succeed and it's a regular file. 1718 */ 1719 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1720 flags = FREAD; 1721 error = vn_open(&nd, &flags, 0, NULL); 1722 if (error == 0) { 1723 NDFREE(&nd, NDF_ONLY_PNBUF); 1724 type = nd.ni_vp->v_type; 1725 if (vap) 1726 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1727 VOP_UNLOCK(nd.ni_vp, 0); 1728 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1729 if (type == VREG) 1730 return (result); 1731 } 1732 } 1733 free(result, M_LINKER); 1734 return (NULL); 1735 } 1736 1737 #define INT_ALIGN(base, ptr) ptr = \ 1738 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1739 1740 /* 1741 * Lookup KLD which contains requested module in the "linker.hints" file. If 1742 * version specification is available, then try to find the best KLD. 1743 * Otherwise just find the latest one. 1744 */ 1745 static char * 1746 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1747 int modnamelen, struct mod_depend *verinfo) 1748 { 1749 struct thread *td = curthread; /* XXX */ 1750 struct ucred *cred = td ? td->td_ucred : NULL; 1751 struct nameidata nd; 1752 struct vattr vattr, mattr; 1753 u_char *hints = NULL; 1754 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1755 int error, ival, bestver, *intp, found, flags, clen, blen; 1756 ssize_t reclen; 1757 1758 result = NULL; 1759 bestver = found = 0; 1760 1761 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1762 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1763 strlen(sep) + 1; 1764 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1765 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1766 linker_hintfile); 1767 1768 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1769 flags = FREAD; 1770 error = vn_open(&nd, &flags, 0, NULL); 1771 if (error) 1772 goto bad; 1773 NDFREE(&nd, NDF_ONLY_PNBUF); 1774 if (nd.ni_vp->v_type != VREG) 1775 goto bad; 1776 best = cp = NULL; 1777 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1778 if (error) 1779 goto bad; 1780 /* 1781 * XXX: we need to limit this number to some reasonable value 1782 */ 1783 if (vattr.va_size > 100 * 1024) { 1784 printf("hints file too large %ld\n", (long)vattr.va_size); 1785 goto bad; 1786 } 1787 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1788 if (hints == NULL) 1789 goto bad; 1790 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1791 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1792 if (error) 1793 goto bad; 1794 VOP_UNLOCK(nd.ni_vp, 0); 1795 vn_close(nd.ni_vp, FREAD, cred, td); 1796 nd.ni_vp = NULL; 1797 if (reclen != 0) { 1798 printf("can't read %zd\n", reclen); 1799 goto bad; 1800 } 1801 intp = (int *)hints; 1802 ival = *intp++; 1803 if (ival != LINKER_HINTS_VERSION) { 1804 printf("hints file version mismatch %d\n", ival); 1805 goto bad; 1806 } 1807 bufend = hints + vattr.va_size; 1808 recptr = (u_char *)intp; 1809 clen = blen = 0; 1810 while (recptr < bufend && !found) { 1811 intp = (int *)recptr; 1812 reclen = *intp++; 1813 ival = *intp++; 1814 cp = (char *)intp; 1815 switch (ival) { 1816 case MDT_VERSION: 1817 clen = *cp++; 1818 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1819 break; 1820 cp += clen; 1821 INT_ALIGN(hints, cp); 1822 ival = *(int *)cp; 1823 cp += sizeof(int); 1824 clen = *cp++; 1825 if (verinfo == NULL || 1826 ival == verinfo->md_ver_preferred) { 1827 found = 1; 1828 break; 1829 } 1830 if (ival >= verinfo->md_ver_minimum && 1831 ival <= verinfo->md_ver_maximum && 1832 ival > bestver) { 1833 bestver = ival; 1834 best = cp; 1835 blen = clen; 1836 } 1837 break; 1838 default: 1839 break; 1840 } 1841 recptr += reclen + sizeof(int); 1842 } 1843 /* 1844 * Finally check if KLD is in the place 1845 */ 1846 if (found) 1847 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1848 else if (best) 1849 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1850 1851 /* 1852 * KLD is newer than hints file. What we should do now? 1853 */ 1854 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1855 printf("warning: KLD '%s' is newer than the linker.hints" 1856 " file\n", result); 1857 bad: 1858 free(pathbuf, M_LINKER); 1859 if (hints) 1860 free(hints, M_TEMP); 1861 if (nd.ni_vp != NULL) { 1862 VOP_UNLOCK(nd.ni_vp, 0); 1863 vn_close(nd.ni_vp, FREAD, cred, td); 1864 } 1865 /* 1866 * If nothing found or hints is absent - fallback to the old 1867 * way by using "kldname[.ko]" as module name. 1868 */ 1869 if (!found && !bestver && result == NULL) 1870 result = linker_lookup_file(path, pathlen, modname, 1871 modnamelen, NULL); 1872 return (result); 1873 } 1874 1875 /* 1876 * Lookup KLD which contains requested module in the all directories. 1877 */ 1878 static char * 1879 linker_search_module(const char *modname, int modnamelen, 1880 struct mod_depend *verinfo) 1881 { 1882 char *cp, *ep, *result; 1883 1884 /* 1885 * traverse the linker path 1886 */ 1887 for (cp = linker_path; *cp; cp = ep + 1) { 1888 /* find the end of this component */ 1889 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1890 result = linker_hints_lookup(cp, ep - cp, modname, 1891 modnamelen, verinfo); 1892 if (result != NULL) 1893 return (result); 1894 if (*ep == 0) 1895 break; 1896 } 1897 return (NULL); 1898 } 1899 1900 /* 1901 * Search for module in all directories listed in the linker_path. 1902 */ 1903 static char * 1904 linker_search_kld(const char *name) 1905 { 1906 char *cp, *ep, *result; 1907 int len; 1908 1909 /* qualified at all? */ 1910 if (strchr(name, '/')) 1911 return (strdup(name, M_LINKER)); 1912 1913 /* traverse the linker path */ 1914 len = strlen(name); 1915 for (ep = linker_path; *ep; ep++) { 1916 cp = ep; 1917 /* find the end of this component */ 1918 for (; *ep != 0 && *ep != ';'; ep++); 1919 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1920 if (result != NULL) 1921 return (result); 1922 } 1923 return (NULL); 1924 } 1925 1926 static const char * 1927 linker_basename(const char *path) 1928 { 1929 const char *filename; 1930 1931 filename = strrchr(path, '/'); 1932 if (filename == NULL) 1933 return path; 1934 if (filename[1]) 1935 filename++; 1936 return (filename); 1937 } 1938 1939 #ifdef HWPMC_HOOKS 1940 /* 1941 * Inform hwpmc about the set of kernel modules currently loaded. 1942 */ 1943 void * 1944 linker_hwpmc_list_objects(void) 1945 { 1946 linker_file_t lf; 1947 struct pmckern_map_in *kobase; 1948 int i, nmappings; 1949 1950 nmappings = 0; 1951 KLD_LOCK_READ(); 1952 TAILQ_FOREACH(lf, &linker_files, link) 1953 nmappings++; 1954 1955 /* Allocate nmappings + 1 entries. */ 1956 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 1957 M_LINKER, M_WAITOK | M_ZERO); 1958 i = 0; 1959 TAILQ_FOREACH(lf, &linker_files, link) { 1960 1961 /* Save the info for this linker file. */ 1962 kobase[i].pm_file = lf->filename; 1963 kobase[i].pm_address = (uintptr_t)lf->address; 1964 i++; 1965 } 1966 KLD_UNLOCK_READ(); 1967 1968 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 1969 1970 /* The last entry of the malloced area comprises of all zeros. */ 1971 KASSERT(kobase[i].pm_file == NULL, 1972 ("linker_hwpmc_list_objects: last object not NULL")); 1973 1974 return ((void *)kobase); 1975 } 1976 #endif 1977 1978 /* 1979 * Find a file which contains given module and load it, if "parent" is not 1980 * NULL, register a reference to it. 1981 */ 1982 static int 1983 linker_load_module(const char *kldname, const char *modname, 1984 struct linker_file *parent, struct mod_depend *verinfo, 1985 struct linker_file **lfpp) 1986 { 1987 linker_file_t lfdep; 1988 const char *filename; 1989 char *pathname; 1990 int error; 1991 1992 KLD_LOCK_ASSERT(); 1993 if (modname == NULL) { 1994 /* 1995 * We have to load KLD 1996 */ 1997 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1998 " is not NULL")); 1999 pathname = linker_search_kld(kldname); 2000 } else { 2001 if (modlist_lookup2(modname, verinfo) != NULL) 2002 return (EEXIST); 2003 if (kldname != NULL) 2004 pathname = strdup(kldname, M_LINKER); 2005 else if (rootvnode == NULL) 2006 pathname = NULL; 2007 else 2008 /* 2009 * Need to find a KLD with required module 2010 */ 2011 pathname = linker_search_module(modname, 2012 strlen(modname), verinfo); 2013 } 2014 if (pathname == NULL) 2015 return (ENOENT); 2016 2017 /* 2018 * Can't load more than one file with the same basename XXX: 2019 * Actually it should be possible to have multiple KLDs with 2020 * the same basename but different path because they can 2021 * provide different versions of the same modules. 2022 */ 2023 filename = linker_basename(pathname); 2024 if (linker_find_file_by_name(filename)) 2025 error = EEXIST; 2026 else do { 2027 error = linker_load_file(pathname, &lfdep); 2028 if (error) 2029 break; 2030 if (modname && verinfo && 2031 modlist_lookup2(modname, verinfo) == NULL) { 2032 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2033 error = ENOENT; 2034 break; 2035 } 2036 if (parent) { 2037 error = linker_file_add_dependency(parent, lfdep); 2038 if (error) 2039 break; 2040 } 2041 if (lfpp) 2042 *lfpp = lfdep; 2043 } while (0); 2044 free(pathname, M_LINKER); 2045 return (error); 2046 } 2047 2048 /* 2049 * This routine is responsible for finding dependencies of userland initiated 2050 * kldload(2)'s of files. 2051 */ 2052 int 2053 linker_load_dependencies(linker_file_t lf) 2054 { 2055 linker_file_t lfdep; 2056 struct mod_metadata **start, **stop, **mdp, **nmdp; 2057 struct mod_metadata *mp, *nmp; 2058 struct mod_depend *verinfo; 2059 modlist_t mod; 2060 const char *modname, *nmodname; 2061 int ver, error = 0, count; 2062 2063 /* 2064 * All files are dependant on /kernel. 2065 */ 2066 KLD_LOCK_ASSERT(); 2067 if (linker_kernel_file) { 2068 linker_kernel_file->refs++; 2069 error = linker_file_add_dependency(lf, linker_kernel_file); 2070 if (error) 2071 return (error); 2072 } 2073 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2074 &count) != 0) 2075 return (0); 2076 for (mdp = start; mdp < stop; mdp++) { 2077 mp = *mdp; 2078 if (mp->md_type != MDT_VERSION) 2079 continue; 2080 modname = mp->md_cval; 2081 ver = ((struct mod_version *)mp->md_data)->mv_version; 2082 mod = modlist_lookup(modname, ver); 2083 if (mod != NULL) { 2084 printf("interface %s.%d already present in the KLD" 2085 " '%s'!\n", modname, ver, 2086 mod->container->filename); 2087 return (EEXIST); 2088 } 2089 } 2090 2091 for (mdp = start; mdp < stop; mdp++) { 2092 mp = *mdp; 2093 if (mp->md_type != MDT_DEPEND) 2094 continue; 2095 modname = mp->md_cval; 2096 verinfo = mp->md_data; 2097 nmodname = NULL; 2098 for (nmdp = start; nmdp < stop; nmdp++) { 2099 nmp = *nmdp; 2100 if (nmp->md_type != MDT_VERSION) 2101 continue; 2102 nmodname = nmp->md_cval; 2103 if (strcmp(modname, nmodname) == 0) 2104 break; 2105 } 2106 if (nmdp < stop)/* early exit, it's a self reference */ 2107 continue; 2108 mod = modlist_lookup2(modname, verinfo); 2109 if (mod) { /* woohoo, it's loaded already */ 2110 lfdep = mod->container; 2111 lfdep->refs++; 2112 error = linker_file_add_dependency(lf, lfdep); 2113 if (error) 2114 break; 2115 continue; 2116 } 2117 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2118 if (error) { 2119 printf("KLD %s: depends on %s - not available or" 2120 " version mismatch\n", lf->filename, modname); 2121 break; 2122 } 2123 } 2124 2125 if (error) 2126 return (error); 2127 linker_addmodules(lf, start, stop, 0); 2128 return (error); 2129 } 2130 2131 static int 2132 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2133 { 2134 struct sysctl_req *req; 2135 2136 req = opaque; 2137 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2138 } 2139 2140 /* 2141 * Export a nul-separated, double-nul-terminated list of all function names 2142 * in the kernel. 2143 */ 2144 static int 2145 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2146 { 2147 linker_file_t lf; 2148 int error; 2149 2150 #ifdef MAC 2151 error = mac_kld_check_stat(req->td->td_ucred); 2152 if (error) 2153 return (error); 2154 #endif 2155 error = sysctl_wire_old_buffer(req, 0); 2156 if (error != 0) 2157 return (error); 2158 KLD_LOCK(); 2159 TAILQ_FOREACH(lf, &linker_files, link) { 2160 error = LINKER_EACH_FUNCTION_NAME(lf, 2161 sysctl_kern_function_list_iterate, req); 2162 if (error) { 2163 KLD_UNLOCK(); 2164 return (error); 2165 } 2166 } 2167 KLD_UNLOCK(); 2168 return (SYSCTL_OUT(req, "", 1)); 2169 } 2170 2171 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLTYPE_OPAQUE | CTLFLAG_RD, 2172 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 2173