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