1 /*- 2 * Copyright (c) 1997-2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_ddb.h" 31 #include "opt_hwpmc_hooks.h" 32 33 #include <sys/param.h> 34 #include <sys/kernel.h> 35 #include <sys/systm.h> 36 #include <sys/malloc.h> 37 #include <sys/sysproto.h> 38 #include <sys/sysent.h> 39 #include <sys/priv.h> 40 #include <sys/proc.h> 41 #include <sys/lock.h> 42 #include <sys/mutex.h> 43 #include <sys/sx.h> 44 #include <sys/module.h> 45 #include <sys/mount.h> 46 #include <sys/linker.h> 47 #include <sys/fcntl.h> 48 #include <sys/jail.h> 49 #include <sys/libkern.h> 50 #include <sys/namei.h> 51 #include <sys/vnode.h> 52 #include <sys/syscallsubr.h> 53 #include <sys/sysctl.h> 54 55 #include <net/vnet.h> 56 57 #include <security/mac/mac_framework.h> 58 59 #include "linker_if.h" 60 61 #ifdef HWPMC_HOOKS 62 #include <sys/pmckern.h> 63 #endif 64 65 #ifdef KLD_DEBUG 66 int kld_debug = 0; 67 SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RW, 68 &kld_debug, 0, "Set various levels of KLD debug"); 69 #endif 70 71 #define KLD_LOCK() sx_xlock(&kld_sx) 72 #define KLD_UNLOCK() sx_xunlock(&kld_sx) 73 #define KLD_DOWNGRADE() sx_downgrade(&kld_sx) 74 #define KLD_LOCK_READ() sx_slock(&kld_sx) 75 #define KLD_UNLOCK_READ() sx_sunlock(&kld_sx) 76 #define KLD_LOCKED() sx_xlocked(&kld_sx) 77 #define KLD_LOCK_ASSERT() do { \ 78 if (!cold) \ 79 sx_assert(&kld_sx, SX_XLOCKED); \ 80 } while (0) 81 82 /* 83 * static char *linker_search_path(const char *name, struct mod_depend 84 * *verinfo); 85 */ 86 static const char *linker_basename(const char *path); 87 88 /* 89 * Find a currently loaded file given its filename. 90 */ 91 static linker_file_t linker_find_file_by_name(const char* _filename); 92 93 /* 94 * Find a currently loaded file given its file id. 95 */ 96 static linker_file_t linker_find_file_by_id(int _fileid); 97 98 /* Metadata from the static kernel */ 99 SET_DECLARE(modmetadata_set, struct mod_metadata); 100 101 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 102 103 linker_file_t linker_kernel_file; 104 105 static struct sx kld_sx; /* kernel linker lock */ 106 107 /* 108 * Load counter used by clients to determine if a linker file has been 109 * re-loaded. This counter is incremented for each file load. 110 */ 111 static int loadcnt; 112 113 static linker_class_list_t classes; 114 static linker_file_list_t linker_files; 115 static int next_file_id = 1; 116 static int linker_no_more_classes = 0; 117 118 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 119 linker_file_t lftmp; \ 120 \ 121 KLD_LOCK_ASSERT(); \ 122 retry: \ 123 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 124 if (next_file_id == lftmp->id) { \ 125 next_file_id++; \ 126 goto retry; \ 127 } \ 128 } \ 129 (a) = next_file_id; \ 130 } while(0) 131 132 133 /* XXX wrong name; we're looking at version provision tags here, not modules */ 134 typedef TAILQ_HEAD(, modlist) modlisthead_t; 135 struct modlist { 136 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 137 linker_file_t container; 138 const char *name; 139 int version; 140 }; 141 typedef struct modlist *modlist_t; 142 static modlisthead_t found_modules; 143 144 static int linker_file_add_dependency(linker_file_t file, 145 linker_file_t dep); 146 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file, 147 const char* name, int deps); 148 static int linker_load_module(const char *kldname, 149 const char *modname, struct linker_file *parent, 150 struct mod_depend *verinfo, struct linker_file **lfpp); 151 static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo); 152 153 static char * 154 linker_strdup(const char *str) 155 { 156 char *result; 157 158 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 159 strcpy(result, str); 160 return (result); 161 } 162 163 static void 164 linker_init(void *arg) 165 { 166 167 sx_init(&kld_sx, "kernel linker"); 168 TAILQ_INIT(&classes); 169 TAILQ_INIT(&linker_files); 170 } 171 172 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); 173 174 static void 175 linker_stop_class_add(void *arg) 176 { 177 178 linker_no_more_classes = 1; 179 } 180 181 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL); 182 183 int 184 linker_add_class(linker_class_t lc) 185 { 186 187 /* 188 * We disallow any class registration past SI_ORDER_ANY 189 * of SI_SUB_KLD. We bump the reference count to keep the 190 * ops from being freed. 191 */ 192 if (linker_no_more_classes == 1) 193 return (EPERM); 194 kobj_class_compile((kobj_class_t) lc); 195 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 196 TAILQ_INSERT_TAIL(&classes, lc, link); 197 return (0); 198 } 199 200 static void 201 linker_file_sysinit(linker_file_t lf) 202 { 203 struct sysinit **start, **stop, **sipp, **xipp, *save; 204 205 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 206 lf->filename)); 207 208 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 209 return; 210 /* 211 * Perform a bubble sort of the system initialization objects by 212 * their subsystem (primary key) and order (secondary key). 213 * 214 * Since some things care about execution order, this is the operation 215 * which ensures continued function. 216 */ 217 for (sipp = start; sipp < stop; sipp++) { 218 for (xipp = sipp + 1; xipp < stop; xipp++) { 219 if ((*sipp)->subsystem < (*xipp)->subsystem || 220 ((*sipp)->subsystem == (*xipp)->subsystem && 221 (*sipp)->order <= (*xipp)->order)) 222 continue; /* skip */ 223 save = *sipp; 224 *sipp = *xipp; 225 *xipp = save; 226 } 227 } 228 229 /* 230 * Traverse the (now) ordered list of system initialization tasks. 231 * Perform each task, and continue on to the next task. 232 */ 233 mtx_lock(&Giant); 234 for (sipp = start; sipp < stop; sipp++) { 235 if ((*sipp)->subsystem == SI_SUB_DUMMY) 236 continue; /* skip dummy task(s) */ 237 238 /* Call function */ 239 (*((*sipp)->func)) ((*sipp)->udata); 240 } 241 mtx_unlock(&Giant); 242 } 243 244 static void 245 linker_file_sysuninit(linker_file_t lf) 246 { 247 struct sysinit **start, **stop, **sipp, **xipp, *save; 248 249 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 250 lf->filename)); 251 252 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 253 NULL) != 0) 254 return; 255 256 /* 257 * Perform a reverse bubble sort of the system initialization objects 258 * by their subsystem (primary key) and order (secondary key). 259 * 260 * Since some things care about execution order, this is the operation 261 * which ensures continued function. 262 */ 263 for (sipp = start; sipp < stop; sipp++) { 264 for (xipp = sipp + 1; xipp < stop; xipp++) { 265 if ((*sipp)->subsystem > (*xipp)->subsystem || 266 ((*sipp)->subsystem == (*xipp)->subsystem && 267 (*sipp)->order >= (*xipp)->order)) 268 continue; /* skip */ 269 save = *sipp; 270 *sipp = *xipp; 271 *xipp = save; 272 } 273 } 274 275 /* 276 * Traverse the (now) ordered list of system initialization tasks. 277 * Perform each task, and continue on to the next task. 278 */ 279 mtx_lock(&Giant); 280 for (sipp = start; sipp < stop; sipp++) { 281 if ((*sipp)->subsystem == SI_SUB_DUMMY) 282 continue; /* skip dummy task(s) */ 283 284 /* Call function */ 285 (*((*sipp)->func)) ((*sipp)->udata); 286 } 287 mtx_unlock(&Giant); 288 } 289 290 static void 291 linker_file_register_sysctls(linker_file_t lf) 292 { 293 struct sysctl_oid **start, **stop, **oidp; 294 295 KLD_DPF(FILE, 296 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 297 lf->filename)); 298 299 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 300 return; 301 302 sysctl_lock(); 303 for (oidp = start; oidp < stop; oidp++) 304 sysctl_register_oid(*oidp); 305 sysctl_unlock(); 306 } 307 308 static void 309 linker_file_unregister_sysctls(linker_file_t lf) 310 { 311 struct sysctl_oid **start, **stop, **oidp; 312 313 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 314 " for %s\n", lf->filename)); 315 316 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 317 return; 318 319 sysctl_lock(); 320 for (oidp = start; oidp < stop; oidp++) 321 sysctl_unregister_oid(*oidp); 322 sysctl_unlock(); 323 } 324 325 static int 326 linker_file_register_modules(linker_file_t lf) 327 { 328 struct mod_metadata **start, **stop, **mdp; 329 const moduledata_t *moddata; 330 int first_error, error; 331 332 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 333 " in %s\n", lf->filename)); 334 335 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 336 &stop, NULL) != 0) { 337 /* 338 * This fallback should be unnecessary, but if we get booted 339 * from boot2 instead of loader and we are missing our 340 * metadata then we have to try the best we can. 341 */ 342 if (lf == linker_kernel_file) { 343 start = SET_BEGIN(modmetadata_set); 344 stop = SET_LIMIT(modmetadata_set); 345 } else 346 return (0); 347 } 348 first_error = 0; 349 for (mdp = start; mdp < stop; mdp++) { 350 if ((*mdp)->md_type != MDT_MODULE) 351 continue; 352 moddata = (*mdp)->md_data; 353 KLD_DPF(FILE, ("Registering module %s in %s\n", 354 moddata->name, lf->filename)); 355 error = module_register(moddata, lf); 356 if (error) { 357 printf("Module %s failed to register: %d\n", 358 moddata->name, error); 359 if (first_error == 0) 360 first_error = error; 361 } 362 } 363 return (first_error); 364 } 365 366 static void 367 linker_init_kernel_modules(void) 368 { 369 370 linker_file_register_modules(linker_kernel_file); 371 } 372 373 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 374 0); 375 376 static int 377 linker_load_file(const char *filename, linker_file_t *result) 378 { 379 linker_class_t lc; 380 linker_file_t lf; 381 int foundfile, error; 382 383 /* Refuse to load modules if securelevel raised */ 384 if (prison0.pr_securelevel > 0) 385 return (EPERM); 386 387 KLD_LOCK_ASSERT(); 388 lf = linker_find_file_by_name(filename); 389 if (lf) { 390 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 391 " incrementing refs\n", filename)); 392 *result = lf; 393 lf->refs++; 394 return (0); 395 } 396 foundfile = 0; 397 error = 0; 398 399 /* 400 * We do not need to protect (lock) classes here because there is 401 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 402 * and there is no class deregistration mechanism at this time. 403 */ 404 TAILQ_FOREACH(lc, &classes, link) { 405 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 406 filename)); 407 error = LINKER_LOAD_FILE(lc, filename, &lf); 408 /* 409 * If we got something other than ENOENT, then it exists but 410 * we cannot load it for some other reason. 411 */ 412 if (error != ENOENT) 413 foundfile = 1; 414 if (lf) { 415 error = linker_file_register_modules(lf); 416 if (error == EEXIST) { 417 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 418 return (error); 419 } 420 KLD_UNLOCK(); 421 linker_file_register_sysctls(lf); 422 linker_file_sysinit(lf); 423 KLD_LOCK(); 424 lf->flags |= LINKER_FILE_LINKED; 425 *result = lf; 426 return (0); 427 } 428 } 429 /* 430 * Less than ideal, but tells the user whether it failed to load or 431 * the module was not found. 432 */ 433 if (foundfile) { 434 435 /* 436 * If the file type has not been recognized by the last try 437 * printout a message before to fail. 438 */ 439 if (error == ENOSYS) 440 printf("linker_load_file: Unsupported file type\n"); 441 442 /* 443 * Format not recognized or otherwise unloadable. 444 * When loading a module that is statically built into 445 * the kernel EEXIST percolates back up as the return 446 * value. Preserve this so that apps like sysinstall 447 * can recognize this special case and not post bogus 448 * dialog boxes. 449 */ 450 if (error != EEXIST) 451 error = ENOEXEC; 452 } else 453 error = ENOENT; /* Nothing found */ 454 return (error); 455 } 456 457 int 458 linker_reference_module(const char *modname, struct mod_depend *verinfo, 459 linker_file_t *result) 460 { 461 modlist_t mod; 462 int error; 463 464 KLD_LOCK(); 465 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 466 *result = mod->container; 467 (*result)->refs++; 468 KLD_UNLOCK(); 469 return (0); 470 } 471 472 error = linker_load_module(NULL, modname, NULL, verinfo, result); 473 KLD_UNLOCK(); 474 return (error); 475 } 476 477 int 478 linker_release_module(const char *modname, struct mod_depend *verinfo, 479 linker_file_t lf) 480 { 481 modlist_t mod; 482 int error; 483 484 KLD_LOCK(); 485 if (lf == NULL) { 486 KASSERT(modname != NULL, 487 ("linker_release_module: no file or name")); 488 mod = modlist_lookup2(modname, verinfo); 489 if (mod == NULL) { 490 KLD_UNLOCK(); 491 return (ESRCH); 492 } 493 lf = mod->container; 494 } else 495 KASSERT(modname == NULL && verinfo == NULL, 496 ("linker_release_module: both file and name")); 497 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 498 KLD_UNLOCK(); 499 return (error); 500 } 501 502 static linker_file_t 503 linker_find_file_by_name(const char *filename) 504 { 505 linker_file_t lf; 506 char *koname; 507 508 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 509 sprintf(koname, "%s.ko", filename); 510 511 KLD_LOCK_ASSERT(); 512 TAILQ_FOREACH(lf, &linker_files, link) { 513 if (strcmp(lf->filename, koname) == 0) 514 break; 515 if (strcmp(lf->filename, filename) == 0) 516 break; 517 } 518 free(koname, M_LINKER); 519 return (lf); 520 } 521 522 static linker_file_t 523 linker_find_file_by_id(int fileid) 524 { 525 linker_file_t lf; 526 527 KLD_LOCK_ASSERT(); 528 TAILQ_FOREACH(lf, &linker_files, link) 529 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 530 break; 531 return (lf); 532 } 533 534 int 535 linker_file_foreach(linker_predicate_t *predicate, void *context) 536 { 537 linker_file_t lf; 538 int retval = 0; 539 540 KLD_LOCK(); 541 TAILQ_FOREACH(lf, &linker_files, link) { 542 retval = predicate(lf, context); 543 if (retval != 0) 544 break; 545 } 546 KLD_UNLOCK(); 547 return (retval); 548 } 549 550 linker_file_t 551 linker_make_file(const char *pathname, linker_class_t lc) 552 { 553 linker_file_t lf; 554 const char *filename; 555 556 KLD_LOCK_ASSERT(); 557 filename = linker_basename(pathname); 558 559 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 560 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 561 if (lf == NULL) 562 return (NULL); 563 lf->refs = 1; 564 lf->userrefs = 0; 565 lf->flags = 0; 566 lf->filename = linker_strdup(filename); 567 lf->pathname = linker_strdup(pathname); 568 LINKER_GET_NEXT_FILE_ID(lf->id); 569 lf->ndeps = 0; 570 lf->deps = NULL; 571 lf->loadcnt = ++loadcnt; 572 lf->sdt_probes = NULL; 573 lf->sdt_nprobes = 0; 574 STAILQ_INIT(&lf->common); 575 TAILQ_INIT(&lf->modules); 576 TAILQ_INSERT_TAIL(&linker_files, lf, link); 577 return (lf); 578 } 579 580 int 581 linker_file_unload(linker_file_t file, int flags) 582 { 583 module_t mod, next; 584 modlist_t ml, nextml; 585 struct common_symbol *cp; 586 int error, i; 587 588 /* Refuse to unload modules if securelevel raised. */ 589 if (prison0.pr_securelevel > 0) 590 return (EPERM); 591 592 KLD_LOCK_ASSERT(); 593 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 594 595 /* Easy case of just dropping a reference. */ 596 if (file->refs > 1) { 597 file->refs--; 598 return (0); 599 } 600 601 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 602 " informing modules\n")); 603 604 /* 605 * Quiesce all the modules to give them a chance to veto the unload. 606 */ 607 MOD_SLOCK; 608 for (mod = TAILQ_FIRST(&file->modules); mod; 609 mod = module_getfnext(mod)) { 610 611 error = module_quiesce(mod); 612 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 613 KLD_DPF(FILE, ("linker_file_unload: module %s" 614 " vetoed unload\n", module_getname(mod))); 615 /* 616 * XXX: Do we need to tell all the quiesced modules 617 * that they can resume work now via a new module 618 * event? 619 */ 620 MOD_SUNLOCK; 621 return (error); 622 } 623 } 624 MOD_SUNLOCK; 625 626 /* 627 * Inform any modules associated with this file that they are 628 * being be unloaded. 629 */ 630 MOD_XLOCK; 631 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 632 next = module_getfnext(mod); 633 MOD_XUNLOCK; 634 635 /* 636 * Give the module a chance to veto the unload. 637 */ 638 if ((error = module_unload(mod)) != 0) { 639 KLD_DPF(FILE, ("linker_file_unload: module %s" 640 " failed unload\n", module_getname(mod))); 641 return (error); 642 } 643 MOD_XLOCK; 644 module_release(mod); 645 } 646 MOD_XUNLOCK; 647 648 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 649 if (ml->container == file) { 650 TAILQ_REMOVE(&found_modules, ml, link); 651 free(ml, M_LINKER); 652 } 653 } 654 655 /* 656 * Don't try to run SYSUNINITs if we are unloaded due to a 657 * link error. 658 */ 659 if (file->flags & LINKER_FILE_LINKED) { 660 file->flags &= ~LINKER_FILE_LINKED; 661 KLD_UNLOCK(); 662 linker_file_sysuninit(file); 663 linker_file_unregister_sysctls(file); 664 KLD_LOCK(); 665 } 666 TAILQ_REMOVE(&linker_files, file, link); 667 668 if (file->deps) { 669 for (i = 0; i < file->ndeps; i++) 670 linker_file_unload(file->deps[i], flags); 671 free(file->deps, M_LINKER); 672 file->deps = NULL; 673 } 674 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 675 STAILQ_REMOVE_HEAD(&file->common, link); 676 free(cp, M_LINKER); 677 } 678 679 LINKER_UNLOAD(file); 680 if (file->filename) { 681 free(file->filename, M_LINKER); 682 file->filename = NULL; 683 } 684 if (file->pathname) { 685 free(file->pathname, M_LINKER); 686 file->pathname = NULL; 687 } 688 kobj_delete((kobj_t) file, M_LINKER); 689 return (0); 690 } 691 692 int 693 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 694 { 695 return (LINKER_CTF_GET(file, lc)); 696 } 697 698 static int 699 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 700 { 701 linker_file_t *newdeps; 702 703 KLD_LOCK_ASSERT(); 704 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 705 M_LINKER, M_WAITOK | M_ZERO); 706 if (newdeps == NULL) 707 return (ENOMEM); 708 709 if (file->deps) { 710 bcopy(file->deps, newdeps, 711 file->ndeps * sizeof(linker_file_t *)); 712 free(file->deps, M_LINKER); 713 } 714 file->deps = newdeps; 715 file->deps[file->ndeps] = dep; 716 file->ndeps++; 717 KLD_DPF(FILE, ("linker_file_add_dependency:" 718 " adding %s as dependency for %s\n", 719 dep->filename, file->filename)); 720 return (0); 721 } 722 723 /* 724 * Locate a linker set and its contents. This is a helper function to avoid 725 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 726 * This function is used in this file so we can avoid having lots of (void **) 727 * casts. 728 */ 729 int 730 linker_file_lookup_set(linker_file_t file, const char *name, 731 void *firstp, void *lastp, int *countp) 732 { 733 int error, locked; 734 735 locked = KLD_LOCKED(); 736 if (!locked) 737 KLD_LOCK(); 738 error = LINKER_LOOKUP_SET(file, name, firstp, lastp, countp); 739 if (!locked) 740 KLD_UNLOCK(); 741 return (error); 742 } 743 744 /* 745 * List all functions in a file. 746 */ 747 int 748 linker_file_function_listall(linker_file_t lf, 749 linker_function_nameval_callback_t callback_func, void *arg) 750 { 751 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 752 } 753 754 caddr_t 755 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 756 { 757 caddr_t sym; 758 int locked; 759 760 locked = KLD_LOCKED(); 761 if (!locked) 762 KLD_LOCK(); 763 sym = linker_file_lookup_symbol_internal(file, name, deps); 764 if (!locked) 765 KLD_UNLOCK(); 766 return (sym); 767 } 768 769 static caddr_t 770 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 771 int deps) 772 { 773 c_linker_sym_t sym; 774 linker_symval_t symval; 775 caddr_t address; 776 size_t common_size = 0; 777 int i; 778 779 KLD_LOCK_ASSERT(); 780 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 781 file, name, deps)); 782 783 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 784 LINKER_SYMBOL_VALUES(file, sym, &symval); 785 if (symval.value == 0) 786 /* 787 * For commons, first look them up in the 788 * dependencies and only allocate space if not found 789 * there. 790 */ 791 common_size = symval.size; 792 else { 793 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 794 ".value=%p\n", symval.value)); 795 return (symval.value); 796 } 797 } 798 if (deps) { 799 for (i = 0; i < file->ndeps; i++) { 800 address = linker_file_lookup_symbol_internal( 801 file->deps[i], name, 0); 802 if (address) { 803 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 804 " deps value=%p\n", address)); 805 return (address); 806 } 807 } 808 } 809 if (common_size > 0) { 810 /* 811 * This is a common symbol which was not found in the 812 * dependencies. We maintain a simple common symbol table in 813 * the file object. 814 */ 815 struct common_symbol *cp; 816 817 STAILQ_FOREACH(cp, &file->common, link) { 818 if (strcmp(cp->name, name) == 0) { 819 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 820 " old common value=%p\n", cp->address)); 821 return (cp->address); 822 } 823 } 824 /* 825 * Round the symbol size up to align. 826 */ 827 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 828 cp = malloc(sizeof(struct common_symbol) 829 + common_size + strlen(name) + 1, M_LINKER, 830 M_WAITOK | M_ZERO); 831 cp->address = (caddr_t)(cp + 1); 832 cp->name = cp->address + common_size; 833 strcpy(cp->name, name); 834 bzero(cp->address, common_size); 835 STAILQ_INSERT_TAIL(&file->common, cp, link); 836 837 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 838 " value=%p\n", cp->address)); 839 return (cp->address); 840 } 841 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 842 return (0); 843 } 844 845 /* 846 * Both DDB and stack(9) rely on the kernel linker to provide forward and 847 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 848 * do this in a lockfree manner. We provide a set of internal helper 849 * routines to perform these operations without locks, and then wrappers that 850 * optionally lock. 851 * 852 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 853 */ 854 #ifdef DDB 855 static int 856 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 857 { 858 linker_file_t lf; 859 860 TAILQ_FOREACH(lf, &linker_files, link) { 861 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 862 return (0); 863 } 864 return (ENOENT); 865 } 866 #endif 867 868 static int 869 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 870 { 871 linker_file_t lf; 872 c_linker_sym_t best, es; 873 u_long diff, bestdiff, off; 874 875 best = 0; 876 off = (uintptr_t)value; 877 bestdiff = off; 878 TAILQ_FOREACH(lf, &linker_files, link) { 879 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 880 continue; 881 if (es != 0 && diff < bestdiff) { 882 best = es; 883 bestdiff = diff; 884 } 885 if (bestdiff == 0) 886 break; 887 } 888 if (best) { 889 *sym = best; 890 *diffp = bestdiff; 891 return (0); 892 } else { 893 *sym = 0; 894 *diffp = off; 895 return (ENOENT); 896 } 897 } 898 899 static int 900 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 901 { 902 linker_file_t lf; 903 904 TAILQ_FOREACH(lf, &linker_files, link) { 905 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 906 return (0); 907 } 908 return (ENOENT); 909 } 910 911 static int 912 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 913 long *offset) 914 { 915 linker_symval_t symval; 916 c_linker_sym_t sym; 917 int error; 918 919 *offset = 0; 920 error = linker_debug_search_symbol(value, &sym, offset); 921 if (error) 922 return (error); 923 error = linker_debug_symbol_values(sym, &symval); 924 if (error) 925 return (error); 926 strlcpy(buf, symval.name, buflen); 927 return (0); 928 } 929 930 /* 931 * DDB Helpers. DDB has to look across multiple files with their own symbol 932 * tables and string tables. 933 * 934 * Note that we do not obey list locking protocols here. We really don't need 935 * DDB to hang because somebody's got the lock held. We'll take the chance 936 * that the files list is inconsistant instead. 937 */ 938 #ifdef DDB 939 int 940 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 941 { 942 943 return (linker_debug_lookup(symstr, sym)); 944 } 945 #endif 946 947 int 948 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 949 { 950 951 return (linker_debug_search_symbol(value, sym, diffp)); 952 } 953 954 int 955 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 956 { 957 958 return (linker_debug_symbol_values(sym, symval)); 959 } 960 961 int 962 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 963 long *offset) 964 { 965 966 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 967 } 968 969 /* 970 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 971 * obey locking protocols, and offer a significantly less complex interface. 972 */ 973 int 974 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 975 long *offset) 976 { 977 int error; 978 979 KLD_LOCK(); 980 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 981 KLD_UNLOCK(); 982 return (error); 983 } 984 985 /* 986 * Syscalls. 987 */ 988 int 989 kern_kldload(struct thread *td, const char *file, int *fileid) 990 { 991 #ifdef HWPMC_HOOKS 992 struct pmckern_map_in pkm; 993 #endif 994 const char *kldname, *modname; 995 linker_file_t lf; 996 int error; 997 998 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 999 return (error); 1000 1001 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 1002 return (error); 1003 1004 /* 1005 * It is possible that kldloaded module will attach a new ifnet, 1006 * so vnet context must be set when this ocurs. 1007 */ 1008 CURVNET_SET(TD_TO_VNET(td)); 1009 1010 /* 1011 * If file does not contain a qualified name or any dot in it 1012 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1013 * name. 1014 */ 1015 if (index(file, '/') || index(file, '.')) { 1016 kldname = file; 1017 modname = NULL; 1018 } else { 1019 kldname = NULL; 1020 modname = file; 1021 } 1022 1023 KLD_LOCK(); 1024 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1025 if (error) { 1026 KLD_UNLOCK(); 1027 goto done; 1028 } 1029 lf->userrefs++; 1030 if (fileid != NULL) 1031 *fileid = lf->id; 1032 #ifdef HWPMC_HOOKS 1033 KLD_DOWNGRADE(); 1034 pkm.pm_file = lf->filename; 1035 pkm.pm_address = (uintptr_t) lf->address; 1036 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 1037 KLD_UNLOCK_READ(); 1038 #else 1039 KLD_UNLOCK(); 1040 #endif 1041 1042 done: 1043 CURVNET_RESTORE(); 1044 return (error); 1045 } 1046 1047 int 1048 kldload(struct thread *td, struct kldload_args *uap) 1049 { 1050 char *pathname = NULL; 1051 int error, fileid; 1052 1053 td->td_retval[0] = -1; 1054 1055 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1056 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1057 if (error == 0) { 1058 error = kern_kldload(td, pathname, &fileid); 1059 if (error == 0) 1060 td->td_retval[0] = fileid; 1061 } 1062 free(pathname, M_TEMP); 1063 return (error); 1064 } 1065 1066 int 1067 kern_kldunload(struct thread *td, int fileid, int flags) 1068 { 1069 #ifdef HWPMC_HOOKS 1070 struct pmckern_map_out pkm; 1071 #endif 1072 linker_file_t lf; 1073 int error = 0; 1074 1075 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1076 return (error); 1077 1078 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1079 return (error); 1080 1081 CURVNET_SET(TD_TO_VNET(td)); 1082 KLD_LOCK(); 1083 lf = linker_find_file_by_id(fileid); 1084 if (lf) { 1085 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1086 1087 /* Check if there are DTrace probes enabled on this file. */ 1088 if (lf->nenabled > 0) { 1089 printf("kldunload: attempt to unload file that has" 1090 " DTrace probes enabled\n"); 1091 error = EBUSY; 1092 } else if (lf->userrefs == 0) { 1093 /* 1094 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1095 */ 1096 printf("kldunload: attempt to unload file that was" 1097 " loaded by the kernel\n"); 1098 error = EBUSY; 1099 } else { 1100 #ifdef HWPMC_HOOKS 1101 /* Save data needed by hwpmc(4) before unloading. */ 1102 pkm.pm_address = (uintptr_t) lf->address; 1103 pkm.pm_size = lf->size; 1104 #endif 1105 lf->userrefs--; 1106 error = linker_file_unload(lf, flags); 1107 if (error) 1108 lf->userrefs++; 1109 } 1110 } else 1111 error = ENOENT; 1112 1113 #ifdef HWPMC_HOOKS 1114 if (error == 0) { 1115 KLD_DOWNGRADE(); 1116 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 1117 KLD_UNLOCK_READ(); 1118 } else 1119 #else 1120 KLD_UNLOCK(); 1121 #endif 1122 CURVNET_RESTORE(); 1123 return (error); 1124 } 1125 1126 int 1127 kldunload(struct thread *td, struct kldunload_args *uap) 1128 { 1129 1130 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1131 } 1132 1133 int 1134 kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1135 { 1136 1137 if (uap->flags != LINKER_UNLOAD_NORMAL && 1138 uap->flags != LINKER_UNLOAD_FORCE) 1139 return (EINVAL); 1140 return (kern_kldunload(td, uap->fileid, uap->flags)); 1141 } 1142 1143 int 1144 kldfind(struct thread *td, struct kldfind_args *uap) 1145 { 1146 char *pathname; 1147 const char *filename; 1148 linker_file_t lf; 1149 int error; 1150 1151 #ifdef MAC 1152 error = mac_kld_check_stat(td->td_ucred); 1153 if (error) 1154 return (error); 1155 #endif 1156 1157 td->td_retval[0] = -1; 1158 1159 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1160 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1161 goto out; 1162 1163 filename = linker_basename(pathname); 1164 KLD_LOCK(); 1165 lf = linker_find_file_by_name(filename); 1166 if (lf) 1167 td->td_retval[0] = lf->id; 1168 else 1169 error = ENOENT; 1170 KLD_UNLOCK(); 1171 out: 1172 free(pathname, M_TEMP); 1173 return (error); 1174 } 1175 1176 int 1177 kldnext(struct thread *td, struct kldnext_args *uap) 1178 { 1179 linker_file_t lf; 1180 int error = 0; 1181 1182 #ifdef MAC 1183 error = mac_kld_check_stat(td->td_ucred); 1184 if (error) 1185 return (error); 1186 #endif 1187 1188 KLD_LOCK(); 1189 if (uap->fileid == 0) 1190 lf = TAILQ_FIRST(&linker_files); 1191 else { 1192 lf = linker_find_file_by_id(uap->fileid); 1193 if (lf == NULL) { 1194 error = ENOENT; 1195 goto out; 1196 } 1197 lf = TAILQ_NEXT(lf, link); 1198 } 1199 1200 /* Skip partially loaded files. */ 1201 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1202 lf = TAILQ_NEXT(lf, link); 1203 1204 if (lf) 1205 td->td_retval[0] = lf->id; 1206 else 1207 td->td_retval[0] = 0; 1208 out: 1209 KLD_UNLOCK(); 1210 return (error); 1211 } 1212 1213 int 1214 kldstat(struct thread *td, struct kldstat_args *uap) 1215 { 1216 struct kld_file_stat stat; 1217 int error, version; 1218 1219 /* 1220 * Check the version of the user's structure. 1221 */ 1222 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) 1223 != 0) 1224 return (error); 1225 if (version != sizeof(struct kld_file_stat_1) && 1226 version != sizeof(struct kld_file_stat)) 1227 return (EINVAL); 1228 1229 error = kern_kldstat(td, uap->fileid, &stat); 1230 if (error != 0) 1231 return (error); 1232 return (copyout(&stat, uap->stat, version)); 1233 } 1234 1235 int 1236 kern_kldstat(struct thread *td, int fileid, struct kld_file_stat *stat) 1237 { 1238 linker_file_t lf; 1239 int namelen; 1240 #ifdef MAC 1241 int error; 1242 1243 error = mac_kld_check_stat(td->td_ucred); 1244 if (error) 1245 return (error); 1246 #endif 1247 1248 KLD_LOCK(); 1249 lf = linker_find_file_by_id(fileid); 1250 if (lf == NULL) { 1251 KLD_UNLOCK(); 1252 return (ENOENT); 1253 } 1254 1255 /* Version 1 fields: */ 1256 namelen = strlen(lf->filename) + 1; 1257 if (namelen > MAXPATHLEN) 1258 namelen = MAXPATHLEN; 1259 bcopy(lf->filename, &stat->name[0], namelen); 1260 stat->refs = lf->refs; 1261 stat->id = lf->id; 1262 stat->address = lf->address; 1263 stat->size = lf->size; 1264 /* Version 2 fields: */ 1265 namelen = strlen(lf->pathname) + 1; 1266 if (namelen > MAXPATHLEN) 1267 namelen = MAXPATHLEN; 1268 bcopy(lf->pathname, &stat->pathname[0], namelen); 1269 KLD_UNLOCK(); 1270 1271 td->td_retval[0] = 0; 1272 return (0); 1273 } 1274 1275 int 1276 kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1277 { 1278 linker_file_t lf; 1279 module_t mp; 1280 int error = 0; 1281 1282 #ifdef MAC 1283 error = mac_kld_check_stat(td->td_ucred); 1284 if (error) 1285 return (error); 1286 #endif 1287 1288 KLD_LOCK(); 1289 lf = linker_find_file_by_id(uap->fileid); 1290 if (lf) { 1291 MOD_SLOCK; 1292 mp = TAILQ_FIRST(&lf->modules); 1293 if (mp != NULL) 1294 td->td_retval[0] = module_getid(mp); 1295 else 1296 td->td_retval[0] = 0; 1297 MOD_SUNLOCK; 1298 } else 1299 error = ENOENT; 1300 KLD_UNLOCK(); 1301 return (error); 1302 } 1303 1304 int 1305 kldsym(struct thread *td, struct kldsym_args *uap) 1306 { 1307 char *symstr = NULL; 1308 c_linker_sym_t sym; 1309 linker_symval_t symval; 1310 linker_file_t lf; 1311 struct kld_sym_lookup lookup; 1312 int error = 0; 1313 1314 #ifdef MAC 1315 error = mac_kld_check_stat(td->td_ucred); 1316 if (error) 1317 return (error); 1318 #endif 1319 1320 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1321 return (error); 1322 if (lookup.version != sizeof(lookup) || 1323 uap->cmd != KLDSYM_LOOKUP) 1324 return (EINVAL); 1325 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1326 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1327 goto out; 1328 KLD_LOCK(); 1329 if (uap->fileid != 0) { 1330 lf = linker_find_file_by_id(uap->fileid); 1331 if (lf == NULL) 1332 error = ENOENT; 1333 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1334 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1335 lookup.symvalue = (uintptr_t) symval.value; 1336 lookup.symsize = symval.size; 1337 error = copyout(&lookup, uap->data, sizeof(lookup)); 1338 } else 1339 error = ENOENT; 1340 } else { 1341 TAILQ_FOREACH(lf, &linker_files, link) { 1342 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1343 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1344 lookup.symvalue = (uintptr_t)symval.value; 1345 lookup.symsize = symval.size; 1346 error = copyout(&lookup, uap->data, 1347 sizeof(lookup)); 1348 break; 1349 } 1350 } 1351 if (lf == NULL) 1352 error = ENOENT; 1353 } 1354 KLD_UNLOCK(); 1355 out: 1356 free(symstr, M_TEMP); 1357 return (error); 1358 } 1359 1360 /* 1361 * Preloaded module support 1362 */ 1363 1364 static modlist_t 1365 modlist_lookup(const char *name, int ver) 1366 { 1367 modlist_t mod; 1368 1369 TAILQ_FOREACH(mod, &found_modules, link) { 1370 if (strcmp(mod->name, name) == 0 && 1371 (ver == 0 || mod->version == ver)) 1372 return (mod); 1373 } 1374 return (NULL); 1375 } 1376 1377 static modlist_t 1378 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1379 { 1380 modlist_t mod, bestmod; 1381 int ver; 1382 1383 if (verinfo == NULL) 1384 return (modlist_lookup(name, 0)); 1385 bestmod = NULL; 1386 TAILQ_FOREACH(mod, &found_modules, link) { 1387 if (strcmp(mod->name, name) != 0) 1388 continue; 1389 ver = mod->version; 1390 if (ver == verinfo->md_ver_preferred) 1391 return (mod); 1392 if (ver >= verinfo->md_ver_minimum && 1393 ver <= verinfo->md_ver_maximum && 1394 (bestmod == NULL || ver > bestmod->version)) 1395 bestmod = mod; 1396 } 1397 return (bestmod); 1398 } 1399 1400 static modlist_t 1401 modlist_newmodule(const char *modname, int version, linker_file_t container) 1402 { 1403 modlist_t mod; 1404 1405 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1406 if (mod == NULL) 1407 panic("no memory for module list"); 1408 mod->container = container; 1409 mod->name = modname; 1410 mod->version = version; 1411 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1412 return (mod); 1413 } 1414 1415 static void 1416 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1417 struct mod_metadata **stop, int preload) 1418 { 1419 struct mod_metadata *mp, **mdp; 1420 const char *modname; 1421 int ver; 1422 1423 for (mdp = start; mdp < stop; mdp++) { 1424 mp = *mdp; 1425 if (mp->md_type != MDT_VERSION) 1426 continue; 1427 modname = mp->md_cval; 1428 ver = ((struct mod_version *)mp->md_data)->mv_version; 1429 if (modlist_lookup(modname, ver) != NULL) { 1430 printf("module %s already present!\n", modname); 1431 /* XXX what can we do? this is a build error. :-( */ 1432 continue; 1433 } 1434 modlist_newmodule(modname, ver, lf); 1435 } 1436 } 1437 1438 static void 1439 linker_preload(void *arg) 1440 { 1441 caddr_t modptr; 1442 const char *modname, *nmodname; 1443 char *modtype; 1444 linker_file_t lf, nlf; 1445 linker_class_t lc; 1446 int error; 1447 linker_file_list_t loaded_files; 1448 linker_file_list_t depended_files; 1449 struct mod_metadata *mp, *nmp; 1450 struct mod_metadata **start, **stop, **mdp, **nmdp; 1451 struct mod_depend *verinfo; 1452 int nver; 1453 int resolves; 1454 modlist_t mod; 1455 struct sysinit **si_start, **si_stop; 1456 1457 TAILQ_INIT(&loaded_files); 1458 TAILQ_INIT(&depended_files); 1459 TAILQ_INIT(&found_modules); 1460 error = 0; 1461 1462 modptr = NULL; 1463 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1464 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1465 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1466 if (modname == NULL) { 1467 printf("Preloaded module at %p does not have a" 1468 " name!\n", modptr); 1469 continue; 1470 } 1471 if (modtype == NULL) { 1472 printf("Preloaded module at %p does not have a type!\n", 1473 modptr); 1474 continue; 1475 } 1476 if (bootverbose) 1477 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1478 modptr); 1479 lf = NULL; 1480 TAILQ_FOREACH(lc, &classes, link) { 1481 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1482 if (!error) 1483 break; 1484 lf = NULL; 1485 } 1486 if (lf) 1487 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1488 } 1489 1490 /* 1491 * First get a list of stuff in the kernel. 1492 */ 1493 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1494 &stop, NULL) == 0) 1495 linker_addmodules(linker_kernel_file, start, stop, 1); 1496 1497 /* 1498 * This is a once-off kinky bubble sort to resolve relocation 1499 * dependency requirements. 1500 */ 1501 restart: 1502 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1503 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1504 &stop, NULL); 1505 /* 1506 * First, look to see if we would successfully link with this 1507 * stuff. 1508 */ 1509 resolves = 1; /* unless we know otherwise */ 1510 if (!error) { 1511 for (mdp = start; mdp < stop; mdp++) { 1512 mp = *mdp; 1513 if (mp->md_type != MDT_DEPEND) 1514 continue; 1515 modname = mp->md_cval; 1516 verinfo = mp->md_data; 1517 for (nmdp = start; nmdp < stop; nmdp++) { 1518 nmp = *nmdp; 1519 if (nmp->md_type != MDT_VERSION) 1520 continue; 1521 nmodname = nmp->md_cval; 1522 if (strcmp(modname, nmodname) == 0) 1523 break; 1524 } 1525 if (nmdp < stop) /* it's a self reference */ 1526 continue; 1527 1528 /* 1529 * ok, the module isn't here yet, we 1530 * are not finished 1531 */ 1532 if (modlist_lookup2(modname, verinfo) == NULL) 1533 resolves = 0; 1534 } 1535 } 1536 /* 1537 * OK, if we found our modules, we can link. So, "provide" 1538 * the modules inside and add it to the end of the link order 1539 * list. 1540 */ 1541 if (resolves) { 1542 if (!error) { 1543 for (mdp = start; mdp < stop; mdp++) { 1544 mp = *mdp; 1545 if (mp->md_type != MDT_VERSION) 1546 continue; 1547 modname = mp->md_cval; 1548 nver = ((struct mod_version *) 1549 mp->md_data)->mv_version; 1550 if (modlist_lookup(modname, 1551 nver) != NULL) { 1552 printf("module %s already" 1553 " present!\n", modname); 1554 TAILQ_REMOVE(&loaded_files, 1555 lf, loaded); 1556 linker_file_unload(lf, 1557 LINKER_UNLOAD_FORCE); 1558 /* we changed tailq next ptr */ 1559 goto restart; 1560 } 1561 modlist_newmodule(modname, nver, lf); 1562 } 1563 } 1564 TAILQ_REMOVE(&loaded_files, lf, loaded); 1565 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1566 /* 1567 * Since we provided modules, we need to restart the 1568 * sort so that the previous files that depend on us 1569 * have a chance. Also, we've busted the tailq next 1570 * pointer with the REMOVE. 1571 */ 1572 goto restart; 1573 } 1574 } 1575 1576 /* 1577 * At this point, we check to see what could not be resolved.. 1578 */ 1579 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1580 TAILQ_REMOVE(&loaded_files, lf, loaded); 1581 printf("KLD file %s is missing dependencies\n", lf->filename); 1582 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1583 } 1584 1585 /* 1586 * We made it. Finish off the linking in the order we determined. 1587 */ 1588 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1589 if (linker_kernel_file) { 1590 linker_kernel_file->refs++; 1591 error = linker_file_add_dependency(lf, 1592 linker_kernel_file); 1593 if (error) 1594 panic("cannot add dependency"); 1595 } 1596 lf->userrefs++; /* so we can (try to) kldunload it */ 1597 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1598 &stop, NULL); 1599 if (!error) { 1600 for (mdp = start; mdp < stop; mdp++) { 1601 mp = *mdp; 1602 if (mp->md_type != MDT_DEPEND) 1603 continue; 1604 modname = mp->md_cval; 1605 verinfo = mp->md_data; 1606 mod = modlist_lookup2(modname, verinfo); 1607 if (mod == NULL) { 1608 printf("KLD file %s - cannot find " 1609 "dependency \"%s\"\n", 1610 lf->filename, modname); 1611 goto fail; 1612 } 1613 /* Don't count self-dependencies */ 1614 if (lf == mod->container) 1615 continue; 1616 mod->container->refs++; 1617 error = linker_file_add_dependency(lf, 1618 mod->container); 1619 if (error) 1620 panic("cannot add dependency"); 1621 } 1622 } 1623 /* 1624 * Now do relocation etc using the symbol search paths 1625 * established by the dependencies 1626 */ 1627 error = LINKER_LINK_PRELOAD_FINISH(lf); 1628 if (error) { 1629 printf("KLD file %s - could not finalize loading\n", 1630 lf->filename); 1631 goto fail; 1632 } 1633 linker_file_register_modules(lf); 1634 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1635 &si_stop, NULL) == 0) 1636 sysinit_add(si_start, si_stop); 1637 linker_file_register_sysctls(lf); 1638 lf->flags |= LINKER_FILE_LINKED; 1639 continue; 1640 fail: 1641 TAILQ_REMOVE(&depended_files, lf, loaded); 1642 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1643 } 1644 /* woohoo! we made it! */ 1645 } 1646 1647 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1648 1649 /* 1650 * Search for a not-loaded module by name. 1651 * 1652 * Modules may be found in the following locations: 1653 * 1654 * - preloaded (result is just the module name) - on disk (result is full path 1655 * to module) 1656 * 1657 * If the module name is qualified in any way (contains path, etc.) the we 1658 * simply return a copy of it. 1659 * 1660 * The search path can be manipulated via sysctl. Note that we use the ';' 1661 * character as a separator to be consistent with the bootloader. 1662 */ 1663 1664 static char linker_hintfile[] = "linker.hints"; 1665 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1666 1667 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1668 sizeof(linker_path), "module load search path"); 1669 1670 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1671 1672 static char *linker_ext_list[] = { 1673 "", 1674 ".ko", 1675 NULL 1676 }; 1677 1678 /* 1679 * Check if file actually exists either with or without extension listed in 1680 * the linker_ext_list. (probably should be generic for the rest of the 1681 * kernel) 1682 */ 1683 static char * 1684 linker_lookup_file(const char *path, int pathlen, const char *name, 1685 int namelen, struct vattr *vap) 1686 { 1687 struct nameidata nd; 1688 struct thread *td = curthread; /* XXX */ 1689 char *result, **cpp, *sep; 1690 int error, len, extlen, reclen, flags, vfslocked; 1691 enum vtype type; 1692 1693 extlen = 0; 1694 for (cpp = linker_ext_list; *cpp; cpp++) { 1695 len = strlen(*cpp); 1696 if (len > extlen) 1697 extlen = len; 1698 } 1699 extlen++; /* trailing '\0' */ 1700 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1701 1702 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1703 result = malloc(reclen, M_LINKER, M_WAITOK); 1704 for (cpp = linker_ext_list; *cpp; cpp++) { 1705 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1706 namelen, name, *cpp); 1707 /* 1708 * Attempt to open the file, and return the path if 1709 * we succeed and it's a regular file. 1710 */ 1711 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, result, td); 1712 flags = FREAD; 1713 error = vn_open(&nd, &flags, 0, NULL); 1714 if (error == 0) { 1715 vfslocked = NDHASGIANT(&nd); 1716 NDFREE(&nd, NDF_ONLY_PNBUF); 1717 type = nd.ni_vp->v_type; 1718 if (vap) 1719 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1720 VOP_UNLOCK(nd.ni_vp, 0); 1721 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1722 VFS_UNLOCK_GIANT(vfslocked); 1723 if (type == VREG) 1724 return (result); 1725 } 1726 } 1727 free(result, M_LINKER); 1728 return (NULL); 1729 } 1730 1731 #define INT_ALIGN(base, ptr) ptr = \ 1732 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1733 1734 /* 1735 * Lookup KLD which contains requested module in the "linker.hints" file. If 1736 * version specification is available, then try to find the best KLD. 1737 * Otherwise just find the latest one. 1738 */ 1739 static char * 1740 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1741 int modnamelen, struct mod_depend *verinfo) 1742 { 1743 struct thread *td = curthread; /* XXX */ 1744 struct ucred *cred = td ? td->td_ucred : NULL; 1745 struct nameidata nd; 1746 struct vattr vattr, mattr; 1747 u_char *hints = NULL; 1748 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1749 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1750 int vfslocked = 0; 1751 1752 result = NULL; 1753 bestver = found = 0; 1754 1755 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1756 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1757 strlen(sep) + 1; 1758 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1759 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1760 linker_hintfile); 1761 1762 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, pathbuf, td); 1763 flags = FREAD; 1764 error = vn_open(&nd, &flags, 0, NULL); 1765 if (error) 1766 goto bad; 1767 vfslocked = NDHASGIANT(&nd); 1768 NDFREE(&nd, NDF_ONLY_PNBUF); 1769 if (nd.ni_vp->v_type != VREG) 1770 goto bad; 1771 best = cp = NULL; 1772 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1773 if (error) 1774 goto bad; 1775 /* 1776 * XXX: we need to limit this number to some reasonable value 1777 */ 1778 if (vattr.va_size > 100 * 1024) { 1779 printf("hints file too large %ld\n", (long)vattr.va_size); 1780 goto bad; 1781 } 1782 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1783 if (hints == NULL) 1784 goto bad; 1785 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1786 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1787 if (error) 1788 goto bad; 1789 VOP_UNLOCK(nd.ni_vp, 0); 1790 vn_close(nd.ni_vp, FREAD, cred, td); 1791 VFS_UNLOCK_GIANT(vfslocked); 1792 nd.ni_vp = NULL; 1793 if (reclen != 0) { 1794 printf("can't read %d\n", reclen); 1795 goto bad; 1796 } 1797 intp = (int *)hints; 1798 ival = *intp++; 1799 if (ival != LINKER_HINTS_VERSION) { 1800 printf("hints file version mismatch %d\n", ival); 1801 goto bad; 1802 } 1803 bufend = hints + vattr.va_size; 1804 recptr = (u_char *)intp; 1805 clen = blen = 0; 1806 while (recptr < bufend && !found) { 1807 intp = (int *)recptr; 1808 reclen = *intp++; 1809 ival = *intp++; 1810 cp = (char *)intp; 1811 switch (ival) { 1812 case MDT_VERSION: 1813 clen = *cp++; 1814 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1815 break; 1816 cp += clen; 1817 INT_ALIGN(hints, cp); 1818 ival = *(int *)cp; 1819 cp += sizeof(int); 1820 clen = *cp++; 1821 if (verinfo == NULL || 1822 ival == verinfo->md_ver_preferred) { 1823 found = 1; 1824 break; 1825 } 1826 if (ival >= verinfo->md_ver_minimum && 1827 ival <= verinfo->md_ver_maximum && 1828 ival > bestver) { 1829 bestver = ival; 1830 best = cp; 1831 blen = clen; 1832 } 1833 break; 1834 default: 1835 break; 1836 } 1837 recptr += reclen + sizeof(int); 1838 } 1839 /* 1840 * Finally check if KLD is in the place 1841 */ 1842 if (found) 1843 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1844 else if (best) 1845 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1846 1847 /* 1848 * KLD is newer than hints file. What we should do now? 1849 */ 1850 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1851 printf("warning: KLD '%s' is newer than the linker.hints" 1852 " file\n", result); 1853 bad: 1854 free(pathbuf, M_LINKER); 1855 if (hints) 1856 free(hints, M_TEMP); 1857 if (nd.ni_vp != NULL) { 1858 VOP_UNLOCK(nd.ni_vp, 0); 1859 vn_close(nd.ni_vp, FREAD, cred, td); 1860 VFS_UNLOCK_GIANT(vfslocked); 1861 } 1862 /* 1863 * If nothing found or hints is absent - fallback to the old 1864 * way by using "kldname[.ko]" as module name. 1865 */ 1866 if (!found && !bestver && result == NULL) 1867 result = linker_lookup_file(path, pathlen, modname, 1868 modnamelen, NULL); 1869 return (result); 1870 } 1871 1872 /* 1873 * Lookup KLD which contains requested module in the all directories. 1874 */ 1875 static char * 1876 linker_search_module(const char *modname, int modnamelen, 1877 struct mod_depend *verinfo) 1878 { 1879 char *cp, *ep, *result; 1880 1881 /* 1882 * traverse the linker path 1883 */ 1884 for (cp = linker_path; *cp; cp = ep + 1) { 1885 /* find the end of this component */ 1886 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1887 result = linker_hints_lookup(cp, ep - cp, modname, 1888 modnamelen, verinfo); 1889 if (result != NULL) 1890 return (result); 1891 if (*ep == 0) 1892 break; 1893 } 1894 return (NULL); 1895 } 1896 1897 /* 1898 * Search for module in all directories listed in the linker_path. 1899 */ 1900 static char * 1901 linker_search_kld(const char *name) 1902 { 1903 char *cp, *ep, *result; 1904 int len; 1905 1906 /* qualified at all? */ 1907 if (index(name, '/')) 1908 return (linker_strdup(name)); 1909 1910 /* traverse the linker path */ 1911 len = strlen(name); 1912 for (ep = linker_path; *ep; ep++) { 1913 cp = ep; 1914 /* find the end of this component */ 1915 for (; *ep != 0 && *ep != ';'; ep++); 1916 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1917 if (result != NULL) 1918 return (result); 1919 } 1920 return (NULL); 1921 } 1922 1923 static const char * 1924 linker_basename(const char *path) 1925 { 1926 const char *filename; 1927 1928 filename = rindex(path, '/'); 1929 if (filename == NULL) 1930 return path; 1931 if (filename[1]) 1932 filename++; 1933 return (filename); 1934 } 1935 1936 #ifdef HWPMC_HOOKS 1937 /* 1938 * Inform hwpmc about the set of kernel modules currently loaded. 1939 */ 1940 void * 1941 linker_hwpmc_list_objects(void) 1942 { 1943 linker_file_t lf; 1944 struct pmckern_map_in *kobase; 1945 int i, nmappings; 1946 1947 nmappings = 0; 1948 KLD_LOCK_READ(); 1949 TAILQ_FOREACH(lf, &linker_files, link) 1950 nmappings++; 1951 1952 /* Allocate nmappings + 1 entries. */ 1953 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 1954 M_LINKER, M_WAITOK | M_ZERO); 1955 i = 0; 1956 TAILQ_FOREACH(lf, &linker_files, link) { 1957 1958 /* Save the info for this linker file. */ 1959 kobase[i].pm_file = lf->filename; 1960 kobase[i].pm_address = (uintptr_t)lf->address; 1961 i++; 1962 } 1963 KLD_UNLOCK_READ(); 1964 1965 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 1966 1967 /* The last entry of the malloced area comprises of all zeros. */ 1968 KASSERT(kobase[i].pm_file == NULL, 1969 ("linker_hwpmc_list_objects: last object not NULL")); 1970 1971 return ((void *)kobase); 1972 } 1973 #endif 1974 1975 /* 1976 * Find a file which contains given module and load it, if "parent" is not 1977 * NULL, register a reference to it. 1978 */ 1979 static int 1980 linker_load_module(const char *kldname, const char *modname, 1981 struct linker_file *parent, struct mod_depend *verinfo, 1982 struct linker_file **lfpp) 1983 { 1984 linker_file_t lfdep; 1985 const char *filename; 1986 char *pathname; 1987 int error; 1988 1989 KLD_LOCK_ASSERT(); 1990 if (modname == NULL) { 1991 /* 1992 * We have to load KLD 1993 */ 1994 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1995 " is not NULL")); 1996 pathname = linker_search_kld(kldname); 1997 } else { 1998 if (modlist_lookup2(modname, verinfo) != NULL) 1999 return (EEXIST); 2000 if (kldname != NULL) 2001 pathname = linker_strdup(kldname); 2002 else if (rootvnode == NULL) 2003 pathname = NULL; 2004 else 2005 /* 2006 * Need to find a KLD with required module 2007 */ 2008 pathname = linker_search_module(modname, 2009 strlen(modname), verinfo); 2010 } 2011 if (pathname == NULL) 2012 return (ENOENT); 2013 2014 /* 2015 * Can't load more than one file with the same basename XXX: 2016 * Actually it should be possible to have multiple KLDs with 2017 * the same basename but different path because they can 2018 * provide different versions of the same modules. 2019 */ 2020 filename = linker_basename(pathname); 2021 if (linker_find_file_by_name(filename)) 2022 error = EEXIST; 2023 else do { 2024 error = linker_load_file(pathname, &lfdep); 2025 if (error) 2026 break; 2027 if (modname && verinfo && 2028 modlist_lookup2(modname, verinfo) == NULL) { 2029 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2030 error = ENOENT; 2031 break; 2032 } 2033 if (parent) { 2034 error = linker_file_add_dependency(parent, lfdep); 2035 if (error) 2036 break; 2037 } 2038 if (lfpp) 2039 *lfpp = lfdep; 2040 } while (0); 2041 free(pathname, M_LINKER); 2042 return (error); 2043 } 2044 2045 /* 2046 * This routine is responsible for finding dependencies of userland initiated 2047 * kldload(2)'s of files. 2048 */ 2049 int 2050 linker_load_dependencies(linker_file_t lf) 2051 { 2052 linker_file_t lfdep; 2053 struct mod_metadata **start, **stop, **mdp, **nmdp; 2054 struct mod_metadata *mp, *nmp; 2055 struct mod_depend *verinfo; 2056 modlist_t mod; 2057 const char *modname, *nmodname; 2058 int ver, error = 0, count; 2059 2060 /* 2061 * All files are dependant on /kernel. 2062 */ 2063 KLD_LOCK_ASSERT(); 2064 if (linker_kernel_file) { 2065 linker_kernel_file->refs++; 2066 error = linker_file_add_dependency(lf, linker_kernel_file); 2067 if (error) 2068 return (error); 2069 } 2070 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2071 &count) != 0) 2072 return (0); 2073 for (mdp = start; mdp < stop; mdp++) { 2074 mp = *mdp; 2075 if (mp->md_type != MDT_VERSION) 2076 continue; 2077 modname = mp->md_cval; 2078 ver = ((struct mod_version *)mp->md_data)->mv_version; 2079 mod = modlist_lookup(modname, ver); 2080 if (mod != NULL) { 2081 printf("interface %s.%d already present in the KLD" 2082 " '%s'!\n", modname, ver, 2083 mod->container->filename); 2084 return (EEXIST); 2085 } 2086 } 2087 2088 for (mdp = start; mdp < stop; mdp++) { 2089 mp = *mdp; 2090 if (mp->md_type != MDT_DEPEND) 2091 continue; 2092 modname = mp->md_cval; 2093 verinfo = mp->md_data; 2094 nmodname = NULL; 2095 for (nmdp = start; nmdp < stop; nmdp++) { 2096 nmp = *nmdp; 2097 if (nmp->md_type != MDT_VERSION) 2098 continue; 2099 nmodname = nmp->md_cval; 2100 if (strcmp(modname, nmodname) == 0) 2101 break; 2102 } 2103 if (nmdp < stop)/* early exit, it's a self reference */ 2104 continue; 2105 mod = modlist_lookup2(modname, verinfo); 2106 if (mod) { /* woohoo, it's loaded already */ 2107 lfdep = mod->container; 2108 lfdep->refs++; 2109 error = linker_file_add_dependency(lf, lfdep); 2110 if (error) 2111 break; 2112 continue; 2113 } 2114 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2115 if (error) { 2116 printf("KLD %s: depends on %s - not available or" 2117 " version mismatch\n", lf->filename, modname); 2118 break; 2119 } 2120 } 2121 2122 if (error) 2123 return (error); 2124 linker_addmodules(lf, start, stop, 0); 2125 return (error); 2126 } 2127 2128 static int 2129 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2130 { 2131 struct sysctl_req *req; 2132 2133 req = opaque; 2134 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2135 } 2136 2137 /* 2138 * Export a nul-separated, double-nul-terminated list of all function names 2139 * in the kernel. 2140 */ 2141 static int 2142 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2143 { 2144 linker_file_t lf; 2145 int error; 2146 2147 #ifdef MAC 2148 error = mac_kld_check_stat(req->td->td_ucred); 2149 if (error) 2150 return (error); 2151 #endif 2152 error = sysctl_wire_old_buffer(req, 0); 2153 if (error != 0) 2154 return (error); 2155 KLD_LOCK(); 2156 TAILQ_FOREACH(lf, &linker_files, link) { 2157 error = LINKER_EACH_FUNCTION_NAME(lf, 2158 sysctl_kern_function_list_iterate, req); 2159 if (error) { 2160 KLD_UNLOCK(); 2161 return (error); 2162 } 2163 } 2164 KLD_UNLOCK(); 2165 return (SYSCTL_OUT(req, "", 1)); 2166 } 2167 2168 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLTYPE_OPAQUE | CTLFLAG_RD, 2169 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 2170