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