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