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(*newdeps), M_LINKER, 729 M_WAITOK | M_ZERO); 730 731 if (file->deps) { 732 bcopy(file->deps, newdeps, file->ndeps * sizeof(*newdeps)); 733 free(file->deps, M_LINKER); 734 } 735 file->deps = newdeps; 736 file->deps[file->ndeps] = dep; 737 file->ndeps++; 738 KLD_DPF(FILE, ("linker_file_add_dependency:" 739 " adding %s as dependency for %s\n", 740 dep->filename, file->filename)); 741 return (0); 742 } 743 744 /* 745 * Locate a linker set and its contents. This is a helper function to avoid 746 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 747 * This function is used in this file so we can avoid having lots of (void **) 748 * casts. 749 */ 750 int 751 linker_file_lookup_set(linker_file_t file, const char *name, 752 void *firstp, void *lastp, int *countp) 753 { 754 755 sx_assert(&kld_sx, SA_LOCKED); 756 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 757 } 758 759 /* 760 * List all functions in a file. 761 */ 762 int 763 linker_file_function_listall(linker_file_t lf, 764 linker_function_nameval_callback_t callback_func, void *arg) 765 { 766 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 767 } 768 769 caddr_t 770 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 771 { 772 caddr_t sym; 773 int locked; 774 775 locked = sx_xlocked(&kld_sx); 776 if (!locked) 777 sx_xlock(&kld_sx); 778 sym = linker_file_lookup_symbol_internal(file, name, deps); 779 if (!locked) 780 sx_xunlock(&kld_sx); 781 return (sym); 782 } 783 784 static caddr_t 785 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 786 int deps) 787 { 788 c_linker_sym_t sym; 789 linker_symval_t symval; 790 caddr_t address; 791 size_t common_size = 0; 792 int i; 793 794 sx_assert(&kld_sx, SA_XLOCKED); 795 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 796 file, name, deps)); 797 798 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 799 LINKER_SYMBOL_VALUES(file, sym, &symval); 800 if (symval.value == 0) 801 /* 802 * For commons, first look them up in the 803 * dependencies and only allocate space if not found 804 * there. 805 */ 806 common_size = symval.size; 807 else { 808 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 809 ".value=%p\n", symval.value)); 810 return (symval.value); 811 } 812 } 813 if (deps) { 814 for (i = 0; i < file->ndeps; i++) { 815 address = linker_file_lookup_symbol_internal( 816 file->deps[i], name, 0); 817 if (address) { 818 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 819 " deps value=%p\n", address)); 820 return (address); 821 } 822 } 823 } 824 if (common_size > 0) { 825 /* 826 * This is a common symbol which was not found in the 827 * dependencies. We maintain a simple common symbol table in 828 * the file object. 829 */ 830 struct common_symbol *cp; 831 832 STAILQ_FOREACH(cp, &file->common, link) { 833 if (strcmp(cp->name, name) == 0) { 834 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 835 " old common value=%p\n", cp->address)); 836 return (cp->address); 837 } 838 } 839 /* 840 * Round the symbol size up to align. 841 */ 842 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 843 cp = malloc(sizeof(struct common_symbol) 844 + common_size + strlen(name) + 1, M_LINKER, 845 M_WAITOK | M_ZERO); 846 cp->address = (caddr_t)(cp + 1); 847 cp->name = cp->address + common_size; 848 strcpy(cp->name, name); 849 bzero(cp->address, common_size); 850 STAILQ_INSERT_TAIL(&file->common, cp, link); 851 852 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 853 " value=%p\n", cp->address)); 854 return (cp->address); 855 } 856 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 857 return (0); 858 } 859 860 /* 861 * Both DDB and stack(9) rely on the kernel linker to provide forward and 862 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 863 * do this in a lockfree manner. We provide a set of internal helper 864 * routines to perform these operations without locks, and then wrappers that 865 * optionally lock. 866 * 867 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 868 */ 869 #ifdef DDB 870 static int 871 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 872 { 873 linker_file_t lf; 874 875 TAILQ_FOREACH(lf, &linker_files, link) { 876 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 877 return (0); 878 } 879 return (ENOENT); 880 } 881 #endif 882 883 static int 884 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 885 { 886 linker_file_t lf; 887 c_linker_sym_t best, es; 888 u_long diff, bestdiff, off; 889 890 best = 0; 891 off = (uintptr_t)value; 892 bestdiff = off; 893 TAILQ_FOREACH(lf, &linker_files, link) { 894 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 895 continue; 896 if (es != 0 && diff < bestdiff) { 897 best = es; 898 bestdiff = diff; 899 } 900 if (bestdiff == 0) 901 break; 902 } 903 if (best) { 904 *sym = best; 905 *diffp = bestdiff; 906 return (0); 907 } else { 908 *sym = 0; 909 *diffp = off; 910 return (ENOENT); 911 } 912 } 913 914 static int 915 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 916 { 917 linker_file_t lf; 918 919 TAILQ_FOREACH(lf, &linker_files, link) { 920 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 921 return (0); 922 } 923 return (ENOENT); 924 } 925 926 static int 927 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 928 long *offset) 929 { 930 linker_symval_t symval; 931 c_linker_sym_t sym; 932 int error; 933 934 *offset = 0; 935 error = linker_debug_search_symbol(value, &sym, offset); 936 if (error) 937 return (error); 938 error = linker_debug_symbol_values(sym, &symval); 939 if (error) 940 return (error); 941 strlcpy(buf, symval.name, buflen); 942 return (0); 943 } 944 945 /* 946 * DDB Helpers. DDB has to look across multiple files with their own symbol 947 * tables and string tables. 948 * 949 * Note that we do not obey list locking protocols here. We really don't need 950 * DDB to hang because somebody's got the lock held. We'll take the chance 951 * that the files list is inconsistant instead. 952 */ 953 #ifdef DDB 954 int 955 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 956 { 957 958 return (linker_debug_lookup(symstr, sym)); 959 } 960 #endif 961 962 int 963 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 964 { 965 966 return (linker_debug_search_symbol(value, sym, diffp)); 967 } 968 969 int 970 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 971 { 972 973 return (linker_debug_symbol_values(sym, symval)); 974 } 975 976 int 977 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 978 long *offset) 979 { 980 981 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 982 } 983 984 /* 985 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 986 * obey locking protocols, and offer a significantly less complex interface. 987 */ 988 int 989 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 990 long *offset) 991 { 992 int error; 993 994 sx_xlock(&kld_sx); 995 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 996 sx_xunlock(&kld_sx); 997 return (error); 998 } 999 1000 /* 1001 * Syscalls. 1002 */ 1003 int 1004 kern_kldload(struct thread *td, const char *file, int *fileid) 1005 { 1006 const char *kldname, *modname; 1007 linker_file_t lf; 1008 int error; 1009 1010 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1011 return (error); 1012 1013 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1014 return (error); 1015 1016 /* 1017 * It is possible that kldloaded module will attach a new ifnet, 1018 * so vnet context must be set when this ocurs. 1019 */ 1020 CURVNET_SET(TD_TO_VNET(td)); 1021 1022 /* 1023 * If file does not contain a qualified name or any dot in it 1024 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1025 * name. 1026 */ 1027 if (strchr(file, '/') || strchr(file, '.')) { 1028 kldname = file; 1029 modname = NULL; 1030 } else { 1031 kldname = NULL; 1032 modname = file; 1033 } 1034 1035 sx_xlock(&kld_sx); 1036 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1037 if (error) { 1038 sx_xunlock(&kld_sx); 1039 goto done; 1040 } 1041 lf->userrefs++; 1042 if (fileid != NULL) 1043 *fileid = lf->id; 1044 sx_xunlock(&kld_sx); 1045 1046 done: 1047 CURVNET_RESTORE(); 1048 return (error); 1049 } 1050 1051 int 1052 sys_kldload(struct thread *td, struct kldload_args *uap) 1053 { 1054 char *pathname = NULL; 1055 int error, fileid; 1056 1057 td->td_retval[0] = -1; 1058 1059 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1060 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1061 if (error == 0) { 1062 error = kern_kldload(td, pathname, &fileid); 1063 if (error == 0) 1064 td->td_retval[0] = fileid; 1065 } 1066 free(pathname, M_TEMP); 1067 return (error); 1068 } 1069 1070 int 1071 kern_kldunload(struct thread *td, int fileid, int flags) 1072 { 1073 linker_file_t lf; 1074 int error = 0; 1075 1076 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1077 return (error); 1078 1079 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1080 return (error); 1081 1082 CURVNET_SET(TD_TO_VNET(td)); 1083 sx_xlock(&kld_sx); 1084 lf = linker_find_file_by_id(fileid); 1085 if (lf) { 1086 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1087 1088 if (lf->userrefs == 0) { 1089 /* 1090 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1091 */ 1092 printf("kldunload: attempt to unload file that was" 1093 " loaded by the kernel\n"); 1094 error = EBUSY; 1095 } else { 1096 lf->userrefs--; 1097 error = linker_file_unload(lf, flags); 1098 if (error) 1099 lf->userrefs++; 1100 } 1101 } else 1102 error = ENOENT; 1103 sx_xunlock(&kld_sx); 1104 1105 CURVNET_RESTORE(); 1106 return (error); 1107 } 1108 1109 int 1110 sys_kldunload(struct thread *td, struct kldunload_args *uap) 1111 { 1112 1113 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1114 } 1115 1116 int 1117 sys_kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1118 { 1119 1120 if (uap->flags != LINKER_UNLOAD_NORMAL && 1121 uap->flags != LINKER_UNLOAD_FORCE) 1122 return (EINVAL); 1123 return (kern_kldunload(td, uap->fileid, uap->flags)); 1124 } 1125 1126 int 1127 sys_kldfind(struct thread *td, struct kldfind_args *uap) 1128 { 1129 char *pathname; 1130 const char *filename; 1131 linker_file_t lf; 1132 int error; 1133 1134 #ifdef MAC 1135 error = mac_kld_check_stat(td->td_ucred); 1136 if (error) 1137 return (error); 1138 #endif 1139 1140 td->td_retval[0] = -1; 1141 1142 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1143 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1144 goto out; 1145 1146 filename = linker_basename(pathname); 1147 sx_xlock(&kld_sx); 1148 lf = linker_find_file_by_name(filename); 1149 if (lf) 1150 td->td_retval[0] = lf->id; 1151 else 1152 error = ENOENT; 1153 sx_xunlock(&kld_sx); 1154 out: 1155 free(pathname, M_TEMP); 1156 return (error); 1157 } 1158 1159 int 1160 sys_kldnext(struct thread *td, struct kldnext_args *uap) 1161 { 1162 linker_file_t lf; 1163 int error = 0; 1164 1165 #ifdef MAC 1166 error = mac_kld_check_stat(td->td_ucred); 1167 if (error) 1168 return (error); 1169 #endif 1170 1171 sx_xlock(&kld_sx); 1172 if (uap->fileid == 0) 1173 lf = TAILQ_FIRST(&linker_files); 1174 else { 1175 lf = linker_find_file_by_id(uap->fileid); 1176 if (lf == NULL) { 1177 error = ENOENT; 1178 goto out; 1179 } 1180 lf = TAILQ_NEXT(lf, link); 1181 } 1182 1183 /* Skip partially loaded files. */ 1184 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1185 lf = TAILQ_NEXT(lf, link); 1186 1187 if (lf) 1188 td->td_retval[0] = lf->id; 1189 else 1190 td->td_retval[0] = 0; 1191 out: 1192 sx_xunlock(&kld_sx); 1193 return (error); 1194 } 1195 1196 int 1197 sys_kldstat(struct thread *td, struct kldstat_args *uap) 1198 { 1199 struct kld_file_stat stat; 1200 int error, version; 1201 1202 /* 1203 * Check the version of the user's structure. 1204 */ 1205 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1206 != 0) 1207 return (error); 1208 if (version != sizeof(struct kld_file_stat_1) && 1209 version != sizeof(struct kld_file_stat)) 1210 return (EINVAL); 1211 1212 error = kern_kldstat(td, uap->fileid, &stat); 1213 if (error != 0) 1214 return (error); 1215 return (copyout(&stat, uap->stat, version)); 1216 } 1217 1218 int 1219 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1220 { 1221 linker_file_t lf; 1222 int namelen; 1223 #ifdef MAC 1224 int error; 1225 1226 error = mac_kld_check_stat(td->td_ucred); 1227 if (error) 1228 return (error); 1229 #endif 1230 1231 sx_xlock(&kld_sx); 1232 lf = linker_find_file_by_id(fileid); 1233 if (lf == NULL) { 1234 sx_xunlock(&kld_sx); 1235 return (ENOENT); 1236 } 1237 1238 /* Version 1 fields: */ 1239 namelen = strlen(lf->filename) + 1; 1240 if (namelen > MAXPATHLEN) 1241 namelen = MAXPATHLEN; 1242 bcopy(lf->filename, &stat->name[0], namelen); 1243 stat->refs = lf->refs; 1244 stat->id = lf->id; 1245 stat->address = lf->address; 1246 stat->size = lf->size; 1247 /* Version 2 fields: */ 1248 namelen = strlen(lf->pathname) + 1; 1249 if (namelen > MAXPATHLEN) 1250 namelen = MAXPATHLEN; 1251 bcopy(lf->pathname, &stat->pathname[0], namelen); 1252 sx_xunlock(&kld_sx); 1253 1254 td->td_retval[0] = 0; 1255 return (0); 1256 } 1257 1258 int 1259 sys_kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1260 { 1261 linker_file_t lf; 1262 module_t mp; 1263 int error = 0; 1264 1265 #ifdef MAC 1266 error = mac_kld_check_stat(td->td_ucred); 1267 if (error) 1268 return (error); 1269 #endif 1270 1271 sx_xlock(&kld_sx); 1272 lf = linker_find_file_by_id(uap->fileid); 1273 if (lf) { 1274 MOD_SLOCK; 1275 mp = TAILQ_FIRST(&lf->modules); 1276 if (mp != NULL) 1277 td->td_retval[0] = module_getid(mp); 1278 else 1279 td->td_retval[0] = 0; 1280 MOD_SUNLOCK; 1281 } else 1282 error = ENOENT; 1283 sx_xunlock(&kld_sx); 1284 return (error); 1285 } 1286 1287 int 1288 sys_kldsym(struct thread *td, struct kldsym_args *uap) 1289 { 1290 char *symstr = NULL; 1291 c_linker_sym_t sym; 1292 linker_symval_t symval; 1293 linker_file_t lf; 1294 struct kld_sym_lookup lookup; 1295 int error = 0; 1296 1297 #ifdef MAC 1298 error = mac_kld_check_stat(td->td_ucred); 1299 if (error) 1300 return (error); 1301 #endif 1302 1303 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1304 return (error); 1305 if (lookup.version != sizeof(lookup) || 1306 uap->cmd != KLDSYM_LOOKUP) 1307 return (EINVAL); 1308 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1309 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1310 goto out; 1311 sx_xlock(&kld_sx); 1312 if (uap->fileid != 0) { 1313 lf = linker_find_file_by_id(uap->fileid); 1314 if (lf == NULL) 1315 error = ENOENT; 1316 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1317 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1318 lookup.symvalue = (uintptr_t) symval.value; 1319 lookup.symsize = symval.size; 1320 error = copyout(&lookup, uap->data, sizeof(lookup)); 1321 } else 1322 error = ENOENT; 1323 } else { 1324 TAILQ_FOREACH(lf, &linker_files, link) { 1325 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1326 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1327 lookup.symvalue = (uintptr_t)symval.value; 1328 lookup.symsize = symval.size; 1329 error = copyout(&lookup, uap->data, 1330 sizeof(lookup)); 1331 break; 1332 } 1333 } 1334 if (lf == NULL) 1335 error = ENOENT; 1336 } 1337 sx_xunlock(&kld_sx); 1338 out: 1339 free(symstr, M_TEMP); 1340 return (error); 1341 } 1342 1343 /* 1344 * Preloaded module support 1345 */ 1346 1347 static modlist_t 1348 modlist_lookup(const char *name, int ver) 1349 { 1350 modlist_t mod; 1351 1352 TAILQ_FOREACH(mod, &found_modules, link) { 1353 if (strcmp(mod->name, name) == 0 && 1354 (ver == 0 || mod->version == ver)) 1355 return (mod); 1356 } 1357 return (NULL); 1358 } 1359 1360 static modlist_t 1361 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1362 { 1363 modlist_t mod, bestmod; 1364 int ver; 1365 1366 if (verinfo == NULL) 1367 return (modlist_lookup(name, 0)); 1368 bestmod = NULL; 1369 TAILQ_FOREACH(mod, &found_modules, link) { 1370 if (strcmp(mod->name, name) != 0) 1371 continue; 1372 ver = mod->version; 1373 if (ver == verinfo->md_ver_preferred) 1374 return (mod); 1375 if (ver >= verinfo->md_ver_minimum && 1376 ver <= verinfo->md_ver_maximum && 1377 (bestmod == NULL || ver > bestmod->version)) 1378 bestmod = mod; 1379 } 1380 return (bestmod); 1381 } 1382 1383 static modlist_t 1384 modlist_newmodule(const char *modname, int version, linker_file_t container) 1385 { 1386 modlist_t mod; 1387 1388 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1389 if (mod == NULL) 1390 panic("no memory for module list"); 1391 mod->container = container; 1392 mod->name = modname; 1393 mod->version = version; 1394 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1395 return (mod); 1396 } 1397 1398 static void 1399 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1400 struct mod_metadata **stop, int preload) 1401 { 1402 struct mod_metadata *mp, **mdp; 1403 const char *modname; 1404 int ver; 1405 1406 for (mdp = start; mdp < stop; mdp++) { 1407 mp = *mdp; 1408 if (mp->md_type != MDT_VERSION) 1409 continue; 1410 modname = mp->md_cval; 1411 ver = ((struct mod_version *)mp->md_data)->mv_version; 1412 if (modlist_lookup(modname, ver) != NULL) { 1413 printf("module %s already present!\n", modname); 1414 /* XXX what can we do? this is a build error. :-( */ 1415 continue; 1416 } 1417 modlist_newmodule(modname, ver, lf); 1418 } 1419 } 1420 1421 static void 1422 linker_preload(void *arg) 1423 { 1424 caddr_t modptr; 1425 const char *modname, *nmodname; 1426 char *modtype; 1427 linker_file_t lf, nlf; 1428 linker_class_t lc; 1429 int error; 1430 linker_file_list_t loaded_files; 1431 linker_file_list_t depended_files; 1432 struct mod_metadata *mp, *nmp; 1433 struct mod_metadata **start, **stop, **mdp, **nmdp; 1434 struct mod_depend *verinfo; 1435 int nver; 1436 int resolves; 1437 modlist_t mod; 1438 struct sysinit **si_start, **si_stop; 1439 1440 TAILQ_INIT(&loaded_files); 1441 TAILQ_INIT(&depended_files); 1442 TAILQ_INIT(&found_modules); 1443 error = 0; 1444 1445 modptr = NULL; 1446 sx_xlock(&kld_sx); 1447 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1448 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1449 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1450 if (modname == NULL) { 1451 printf("Preloaded module at %p does not have a" 1452 " name!\n", modptr); 1453 continue; 1454 } 1455 if (modtype == NULL) { 1456 printf("Preloaded module at %p does not have a type!\n", 1457 modptr); 1458 continue; 1459 } 1460 if (bootverbose) 1461 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1462 modptr); 1463 lf = NULL; 1464 TAILQ_FOREACH(lc, &classes, link) { 1465 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1466 if (!error) 1467 break; 1468 lf = NULL; 1469 } 1470 if (lf) 1471 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1472 } 1473 1474 /* 1475 * First get a list of stuff in the kernel. 1476 */ 1477 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1478 &stop, NULL) == 0) 1479 linker_addmodules(linker_kernel_file, start, stop, 1); 1480 1481 /* 1482 * This is a once-off kinky bubble sort to resolve relocation 1483 * dependency requirements. 1484 */ 1485 restart: 1486 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1487 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1488 &stop, NULL); 1489 /* 1490 * First, look to see if we would successfully link with this 1491 * stuff. 1492 */ 1493 resolves = 1; /* unless we know otherwise */ 1494 if (!error) { 1495 for (mdp = start; mdp < stop; mdp++) { 1496 mp = *mdp; 1497 if (mp->md_type != MDT_DEPEND) 1498 continue; 1499 modname = mp->md_cval; 1500 verinfo = mp->md_data; 1501 for (nmdp = start; nmdp < stop; nmdp++) { 1502 nmp = *nmdp; 1503 if (nmp->md_type != MDT_VERSION) 1504 continue; 1505 nmodname = nmp->md_cval; 1506 if (strcmp(modname, nmodname) == 0) 1507 break; 1508 } 1509 if (nmdp < stop) /* it's a self reference */ 1510 continue; 1511 1512 /* 1513 * ok, the module isn't here yet, we 1514 * are not finished 1515 */ 1516 if (modlist_lookup2(modname, verinfo) == NULL) 1517 resolves = 0; 1518 } 1519 } 1520 /* 1521 * OK, if we found our modules, we can link. So, "provide" 1522 * the modules inside and add it to the end of the link order 1523 * list. 1524 */ 1525 if (resolves) { 1526 if (!error) { 1527 for (mdp = start; mdp < stop; mdp++) { 1528 mp = *mdp; 1529 if (mp->md_type != MDT_VERSION) 1530 continue; 1531 modname = mp->md_cval; 1532 nver = ((struct mod_version *) 1533 mp->md_data)->mv_version; 1534 if (modlist_lookup(modname, 1535 nver) != NULL) { 1536 printf("module %s already" 1537 " present!\n", modname); 1538 TAILQ_REMOVE(&loaded_files, 1539 lf, loaded); 1540 linker_file_unload(lf, 1541 LINKER_UNLOAD_FORCE); 1542 /* we changed tailq next ptr */ 1543 goto restart; 1544 } 1545 modlist_newmodule(modname, nver, lf); 1546 } 1547 } 1548 TAILQ_REMOVE(&loaded_files, lf, loaded); 1549 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1550 /* 1551 * Since we provided modules, we need to restart the 1552 * sort so that the previous files that depend on us 1553 * have a chance. Also, we've busted the tailq next 1554 * pointer with the REMOVE. 1555 */ 1556 goto restart; 1557 } 1558 } 1559 1560 /* 1561 * At this point, we check to see what could not be resolved.. 1562 */ 1563 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1564 TAILQ_REMOVE(&loaded_files, lf, loaded); 1565 printf("KLD file %s is missing dependencies\n", lf->filename); 1566 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1567 } 1568 1569 /* 1570 * We made it. Finish off the linking in the order we determined. 1571 */ 1572 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1573 if (linker_kernel_file) { 1574 linker_kernel_file->refs++; 1575 error = linker_file_add_dependency(lf, 1576 linker_kernel_file); 1577 if (error) 1578 panic("cannot add dependency"); 1579 } 1580 lf->userrefs++; /* so we can (try to) kldunload it */ 1581 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1582 &stop, NULL); 1583 if (!error) { 1584 for (mdp = start; mdp < stop; mdp++) { 1585 mp = *mdp; 1586 if (mp->md_type != MDT_DEPEND) 1587 continue; 1588 modname = mp->md_cval; 1589 verinfo = mp->md_data; 1590 mod = modlist_lookup2(modname, verinfo); 1591 if (mod == NULL) { 1592 printf("KLD file %s - cannot find " 1593 "dependency \"%s\"\n", 1594 lf->filename, modname); 1595 goto fail; 1596 } 1597 /* Don't count self-dependencies */ 1598 if (lf == mod->container) 1599 continue; 1600 mod->container->refs++; 1601 error = linker_file_add_dependency(lf, 1602 mod->container); 1603 if (error) 1604 panic("cannot add dependency"); 1605 } 1606 } 1607 /* 1608 * Now do relocation etc using the symbol search paths 1609 * established by the dependencies 1610 */ 1611 error = LINKER_LINK_PRELOAD_FINISH(lf); 1612 if (error) { 1613 printf("KLD file %s - could not finalize loading\n", 1614 lf->filename); 1615 goto fail; 1616 } 1617 linker_file_register_modules(lf); 1618 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1619 &si_stop, NULL) == 0) 1620 sysinit_add(si_start, si_stop); 1621 linker_file_register_sysctls(lf); 1622 lf->flags |= LINKER_FILE_LINKED; 1623 continue; 1624 fail: 1625 TAILQ_REMOVE(&depended_files, lf, loaded); 1626 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1627 } 1628 sx_xunlock(&kld_sx); 1629 /* woohoo! we made it! */ 1630 } 1631 1632 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1633 1634 /* 1635 * Search for a not-loaded module by name. 1636 * 1637 * Modules may be found in the following locations: 1638 * 1639 * - preloaded (result is just the module name) - on disk (result is full path 1640 * to module) 1641 * 1642 * If the module name is qualified in any way (contains path, etc.) the we 1643 * simply return a copy of it. 1644 * 1645 * The search path can be manipulated via sysctl. Note that we use the ';' 1646 * character as a separator to be consistent with the bootloader. 1647 */ 1648 1649 static char linker_hintfile[] = "linker.hints"; 1650 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1651 1652 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1653 sizeof(linker_path), "module load search path"); 1654 1655 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1656 1657 static char *linker_ext_list[] = { 1658 "", 1659 ".ko", 1660 NULL 1661 }; 1662 1663 /* 1664 * Check if file actually exists either with or without extension listed in 1665 * the linker_ext_list. (probably should be generic for the rest of the 1666 * kernel) 1667 */ 1668 static char * 1669 linker_lookup_file(const char *path, int pathlen, const char *name, 1670 int namelen, struct vattr *vap) 1671 { 1672 struct nameidata nd; 1673 struct thread *td = curthread; /* XXX */ 1674 char *result, **cpp, *sep; 1675 int error, len, extlen, reclen, flags; 1676 enum vtype type; 1677 1678 extlen = 0; 1679 for (cpp = linker_ext_list; *cpp; cpp++) { 1680 len = strlen(*cpp); 1681 if (len > extlen) 1682 extlen = len; 1683 } 1684 extlen++; /* trailing '\0' */ 1685 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1686 1687 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1688 result = malloc(reclen, M_LINKER, M_WAITOK); 1689 for (cpp = linker_ext_list; *cpp; cpp++) { 1690 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1691 namelen, name, *cpp); 1692 /* 1693 * Attempt to open the file, and return the path if 1694 * we succeed and it's a regular file. 1695 */ 1696 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1697 flags = FREAD; 1698 error = vn_open(&nd, &flags, 0, NULL); 1699 if (error == 0) { 1700 NDFREE(&nd, NDF_ONLY_PNBUF); 1701 type = nd.ni_vp->v_type; 1702 if (vap) 1703 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1704 VOP_UNLOCK(nd.ni_vp, 0); 1705 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1706 if (type == VREG) 1707 return (result); 1708 } 1709 } 1710 free(result, M_LINKER); 1711 return (NULL); 1712 } 1713 1714 #define INT_ALIGN(base, ptr) ptr = \ 1715 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1716 1717 /* 1718 * Lookup KLD which contains requested module in the "linker.hints" file. If 1719 * version specification is available, then try to find the best KLD. 1720 * Otherwise just find the latest one. 1721 */ 1722 static char * 1723 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1724 int modnamelen, struct mod_depend *verinfo) 1725 { 1726 struct thread *td = curthread; /* XXX */ 1727 struct ucred *cred = td ? td->td_ucred : NULL; 1728 struct nameidata nd; 1729 struct vattr vattr, mattr; 1730 u_char *hints = NULL; 1731 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1732 int error, ival, bestver, *intp, found, flags, clen, blen; 1733 ssize_t reclen; 1734 1735 result = NULL; 1736 bestver = found = 0; 1737 1738 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1739 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1740 strlen(sep) + 1; 1741 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1742 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1743 linker_hintfile); 1744 1745 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1746 flags = FREAD; 1747 error = vn_open(&nd, &flags, 0, NULL); 1748 if (error) 1749 goto bad; 1750 NDFREE(&nd, NDF_ONLY_PNBUF); 1751 if (nd.ni_vp->v_type != VREG) 1752 goto bad; 1753 best = cp = NULL; 1754 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1755 if (error) 1756 goto bad; 1757 /* 1758 * XXX: we need to limit this number to some reasonable value 1759 */ 1760 if (vattr.va_size > 100 * 1024) { 1761 printf("hints file too large %ld\n", (long)vattr.va_size); 1762 goto bad; 1763 } 1764 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1765 if (hints == NULL) 1766 goto bad; 1767 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1768 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1769 if (error) 1770 goto bad; 1771 VOP_UNLOCK(nd.ni_vp, 0); 1772 vn_close(nd.ni_vp, FREAD, cred, td); 1773 nd.ni_vp = NULL; 1774 if (reclen != 0) { 1775 printf("can't read %zd\n", reclen); 1776 goto bad; 1777 } 1778 intp = (int *)hints; 1779 ival = *intp++; 1780 if (ival != LINKER_HINTS_VERSION) { 1781 printf("hints file version mismatch %d\n", ival); 1782 goto bad; 1783 } 1784 bufend = hints + vattr.va_size; 1785 recptr = (u_char *)intp; 1786 clen = blen = 0; 1787 while (recptr < bufend && !found) { 1788 intp = (int *)recptr; 1789 reclen = *intp++; 1790 ival = *intp++; 1791 cp = (char *)intp; 1792 switch (ival) { 1793 case MDT_VERSION: 1794 clen = *cp++; 1795 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1796 break; 1797 cp += clen; 1798 INT_ALIGN(hints, cp); 1799 ival = *(int *)cp; 1800 cp += sizeof(int); 1801 clen = *cp++; 1802 if (verinfo == NULL || 1803 ival == verinfo->md_ver_preferred) { 1804 found = 1; 1805 break; 1806 } 1807 if (ival >= verinfo->md_ver_minimum && 1808 ival <= verinfo->md_ver_maximum && 1809 ival > bestver) { 1810 bestver = ival; 1811 best = cp; 1812 blen = clen; 1813 } 1814 break; 1815 default: 1816 break; 1817 } 1818 recptr += reclen + sizeof(int); 1819 } 1820 /* 1821 * Finally check if KLD is in the place 1822 */ 1823 if (found) 1824 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1825 else if (best) 1826 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1827 1828 /* 1829 * KLD is newer than hints file. What we should do now? 1830 */ 1831 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1832 printf("warning: KLD '%s' is newer than the linker.hints" 1833 " file\n", result); 1834 bad: 1835 free(pathbuf, M_LINKER); 1836 if (hints) 1837 free(hints, M_TEMP); 1838 if (nd.ni_vp != NULL) { 1839 VOP_UNLOCK(nd.ni_vp, 0); 1840 vn_close(nd.ni_vp, FREAD, cred, td); 1841 } 1842 /* 1843 * If nothing found or hints is absent - fallback to the old 1844 * way by using "kldname[.ko]" as module name. 1845 */ 1846 if (!found && !bestver && result == NULL) 1847 result = linker_lookup_file(path, pathlen, modname, 1848 modnamelen, NULL); 1849 return (result); 1850 } 1851 1852 /* 1853 * Lookup KLD which contains requested module in the all directories. 1854 */ 1855 static char * 1856 linker_search_module(const char *modname, int modnamelen, 1857 struct mod_depend *verinfo) 1858 { 1859 char *cp, *ep, *result; 1860 1861 /* 1862 * traverse the linker path 1863 */ 1864 for (cp = linker_path; *cp; cp = ep + 1) { 1865 /* find the end of this component */ 1866 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1867 result = linker_hints_lookup(cp, ep - cp, modname, 1868 modnamelen, verinfo); 1869 if (result != NULL) 1870 return (result); 1871 if (*ep == 0) 1872 break; 1873 } 1874 return (NULL); 1875 } 1876 1877 /* 1878 * Search for module in all directories listed in the linker_path. 1879 */ 1880 static char * 1881 linker_search_kld(const char *name) 1882 { 1883 char *cp, *ep, *result; 1884 int len; 1885 1886 /* qualified at all? */ 1887 if (strchr(name, '/')) 1888 return (strdup(name, M_LINKER)); 1889 1890 /* traverse the linker path */ 1891 len = strlen(name); 1892 for (ep = linker_path; *ep; ep++) { 1893 cp = ep; 1894 /* find the end of this component */ 1895 for (; *ep != 0 && *ep != ';'; ep++); 1896 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1897 if (result != NULL) 1898 return (result); 1899 } 1900 return (NULL); 1901 } 1902 1903 static const char * 1904 linker_basename(const char *path) 1905 { 1906 const char *filename; 1907 1908 filename = strrchr(path, '/'); 1909 if (filename == NULL) 1910 return path; 1911 if (filename[1]) 1912 filename++; 1913 return (filename); 1914 } 1915 1916 #ifdef HWPMC_HOOKS 1917 /* 1918 * Inform hwpmc about the set of kernel modules currently loaded. 1919 */ 1920 void * 1921 linker_hwpmc_list_objects(void) 1922 { 1923 linker_file_t lf; 1924 struct pmckern_map_in *kobase; 1925 int i, nmappings; 1926 1927 nmappings = 0; 1928 sx_slock(&kld_sx); 1929 TAILQ_FOREACH(lf, &linker_files, link) 1930 nmappings++; 1931 1932 /* Allocate nmappings + 1 entries. */ 1933 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 1934 M_LINKER, M_WAITOK | M_ZERO); 1935 i = 0; 1936 TAILQ_FOREACH(lf, &linker_files, link) { 1937 1938 /* Save the info for this linker file. */ 1939 kobase[i].pm_file = lf->filename; 1940 kobase[i].pm_address = (uintptr_t)lf->address; 1941 i++; 1942 } 1943 sx_sunlock(&kld_sx); 1944 1945 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 1946 1947 /* The last entry of the malloced area comprises of all zeros. */ 1948 KASSERT(kobase[i].pm_file == NULL, 1949 ("linker_hwpmc_list_objects: last object not NULL")); 1950 1951 return ((void *)kobase); 1952 } 1953 #endif 1954 1955 /* 1956 * Find a file which contains given module and load it, if "parent" is not 1957 * NULL, register a reference to it. 1958 */ 1959 static int 1960 linker_load_module(const char *kldname, const char *modname, 1961 struct linker_file *parent, struct mod_depend *verinfo, 1962 struct linker_file **lfpp) 1963 { 1964 linker_file_t lfdep; 1965 const char *filename; 1966 char *pathname; 1967 int error; 1968 1969 sx_assert(&kld_sx, SA_XLOCKED); 1970 if (modname == NULL) { 1971 /* 1972 * We have to load KLD 1973 */ 1974 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1975 " is not NULL")); 1976 pathname = linker_search_kld(kldname); 1977 } else { 1978 if (modlist_lookup2(modname, verinfo) != NULL) 1979 return (EEXIST); 1980 if (kldname != NULL) 1981 pathname = strdup(kldname, M_LINKER); 1982 else if (rootvnode == NULL) 1983 pathname = NULL; 1984 else 1985 /* 1986 * Need to find a KLD with required module 1987 */ 1988 pathname = linker_search_module(modname, 1989 strlen(modname), verinfo); 1990 } 1991 if (pathname == NULL) 1992 return (ENOENT); 1993 1994 /* 1995 * Can't load more than one file with the same basename XXX: 1996 * Actually it should be possible to have multiple KLDs with 1997 * the same basename but different path because they can 1998 * provide different versions of the same modules. 1999 */ 2000 filename = linker_basename(pathname); 2001 if (linker_find_file_by_name(filename)) 2002 error = EEXIST; 2003 else do { 2004 error = linker_load_file(pathname, &lfdep); 2005 if (error) 2006 break; 2007 if (modname && verinfo && 2008 modlist_lookup2(modname, verinfo) == NULL) { 2009 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2010 error = ENOENT; 2011 break; 2012 } 2013 if (parent) { 2014 error = linker_file_add_dependency(parent, lfdep); 2015 if (error) 2016 break; 2017 } 2018 if (lfpp) 2019 *lfpp = lfdep; 2020 } while (0); 2021 free(pathname, M_LINKER); 2022 return (error); 2023 } 2024 2025 /* 2026 * This routine is responsible for finding dependencies of userland initiated 2027 * kldload(2)'s of files. 2028 */ 2029 int 2030 linker_load_dependencies(linker_file_t lf) 2031 { 2032 linker_file_t lfdep; 2033 struct mod_metadata **start, **stop, **mdp, **nmdp; 2034 struct mod_metadata *mp, *nmp; 2035 struct mod_depend *verinfo; 2036 modlist_t mod; 2037 const char *modname, *nmodname; 2038 int ver, error = 0, count; 2039 2040 /* 2041 * All files are dependant on /kernel. 2042 */ 2043 sx_assert(&kld_sx, SA_XLOCKED); 2044 if (linker_kernel_file) { 2045 linker_kernel_file->refs++; 2046 error = linker_file_add_dependency(lf, linker_kernel_file); 2047 if (error) 2048 return (error); 2049 } 2050 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2051 &count) != 0) 2052 return (0); 2053 for (mdp = start; mdp < stop; mdp++) { 2054 mp = *mdp; 2055 if (mp->md_type != MDT_VERSION) 2056 continue; 2057 modname = mp->md_cval; 2058 ver = ((struct mod_version *)mp->md_data)->mv_version; 2059 mod = modlist_lookup(modname, ver); 2060 if (mod != NULL) { 2061 printf("interface %s.%d already present in the KLD" 2062 " '%s'!\n", modname, ver, 2063 mod->container->filename); 2064 return (EEXIST); 2065 } 2066 } 2067 2068 for (mdp = start; mdp < stop; mdp++) { 2069 mp = *mdp; 2070 if (mp->md_type != MDT_DEPEND) 2071 continue; 2072 modname = mp->md_cval; 2073 verinfo = mp->md_data; 2074 nmodname = NULL; 2075 for (nmdp = start; nmdp < stop; nmdp++) { 2076 nmp = *nmdp; 2077 if (nmp->md_type != MDT_VERSION) 2078 continue; 2079 nmodname = nmp->md_cval; 2080 if (strcmp(modname, nmodname) == 0) 2081 break; 2082 } 2083 if (nmdp < stop)/* early exit, it's a self reference */ 2084 continue; 2085 mod = modlist_lookup2(modname, verinfo); 2086 if (mod) { /* woohoo, it's loaded already */ 2087 lfdep = mod->container; 2088 lfdep->refs++; 2089 error = linker_file_add_dependency(lf, lfdep); 2090 if (error) 2091 break; 2092 continue; 2093 } 2094 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2095 if (error) { 2096 printf("KLD %s: depends on %s - not available or" 2097 " version mismatch\n", lf->filename, modname); 2098 break; 2099 } 2100 } 2101 2102 if (error) 2103 return (error); 2104 linker_addmodules(lf, start, stop, 0); 2105 return (error); 2106 } 2107 2108 static int 2109 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2110 { 2111 struct sysctl_req *req; 2112 2113 req = opaque; 2114 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2115 } 2116 2117 /* 2118 * Export a nul-separated, double-nul-terminated list of all function names 2119 * in the kernel. 2120 */ 2121 static int 2122 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2123 { 2124 linker_file_t lf; 2125 int error; 2126 2127 #ifdef MAC 2128 error = mac_kld_check_stat(req->td->td_ucred); 2129 if (error) 2130 return (error); 2131 #endif 2132 error = sysctl_wire_old_buffer(req, 0); 2133 if (error != 0) 2134 return (error); 2135 sx_xlock(&kld_sx); 2136 TAILQ_FOREACH(lf, &linker_files, link) { 2137 error = LINKER_EACH_FUNCTION_NAME(lf, 2138 sysctl_kern_function_list_iterate, req); 2139 if (error) { 2140 sx_xunlock(&kld_sx); 2141 return (error); 2142 } 2143 } 2144 sx_xunlock(&kld_sx); 2145 return (SYSCTL_OUT(req, "", 1)); 2146 } 2147 2148 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLTYPE_OPAQUE | CTLFLAG_RD, 2149 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 2150