kern_linker.c revision 159797
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: head/sys/kern/kern_linker.c 159797 2006-06-20 20:37:17Z jhb $"); 29 30#include "opt_ddb.h" 31#include "opt_hwpmc_hooks.h" 32#include "opt_mac.h" 33 34#include <sys/param.h> 35#include <sys/kernel.h> 36#include <sys/systm.h> 37#include <sys/malloc.h> 38#include <sys/sysproto.h> 39#include <sys/sysent.h> 40#include <sys/proc.h> 41#include <sys/lock.h> 42#include <sys/mutex.h> 43#include <sys/sx.h> 44#include <sys/mac.h> 45#include <sys/module.h> 46#include <sys/linker.h> 47#include <sys/fcntl.h> 48#include <sys/libkern.h> 49#include <sys/namei.h> 50#include <sys/vnode.h> 51#include <sys/syscallsubr.h> 52#include <sys/sysctl.h> 53 54#include "linker_if.h" 55 56#ifdef HWPMC_HOOKS 57#include <sys/pmckern.h> 58#endif 59 60#ifdef KLD_DEBUG 61int kld_debug = 0; 62#endif 63 64/* 65 * static char *linker_search_path(const char *name, struct mod_depend 66 * *verinfo); 67 */ 68static const char *linker_basename(const char *path); 69 70/* Metadata from the static kernel */ 71SET_DECLARE(modmetadata_set, struct mod_metadata); 72 73MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 74 75linker_file_t linker_kernel_file; 76 77static struct mtx kld_mtx; /* kernel linker mutex */ 78 79static linker_class_list_t classes; 80static linker_file_list_t linker_files; 81static int next_file_id = 1; 82static int linker_no_more_classes = 0; 83 84#define LINKER_GET_NEXT_FILE_ID(a) do { \ 85 linker_file_t lftmp; \ 86 \ 87retry: \ 88 mtx_lock(&kld_mtx); \ 89 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 90 if (next_file_id == lftmp->id) { \ 91 next_file_id++; \ 92 mtx_unlock(&kld_mtx); \ 93 goto retry; \ 94 } \ 95 } \ 96 (a) = next_file_id; \ 97 mtx_unlock(&kld_mtx); /* Hold for safe read of id variable */ \ 98} while(0) 99 100 101/* XXX wrong name; we're looking at version provision tags here, not modules */ 102typedef TAILQ_HEAD(, modlist) modlisthead_t; 103struct modlist { 104 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 105 linker_file_t container; 106 const char *name; 107 int version; 108}; 109typedef struct modlist *modlist_t; 110static modlisthead_t found_modules; 111 112static int linker_file_add_dependency(linker_file_t file, 113 linker_file_t dep); 114static int linker_load_module(const char *kldname, 115 const char *modname, struct linker_file *parent, 116 struct mod_depend *verinfo, struct linker_file **lfpp); 117static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo); 118 119static char * 120linker_strdup(const char *str) 121{ 122 char *result; 123 124 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 125 strcpy(result, str); 126 return (result); 127} 128 129static void 130linker_init(void *arg) 131{ 132 133 mtx_init(&kld_mtx, "kernel linker", NULL, MTX_DEF); 134 TAILQ_INIT(&classes); 135 TAILQ_INIT(&linker_files); 136} 137 138SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 139 140static void 141linker_stop_class_add(void *arg) 142{ 143 144 linker_no_more_classes = 1; 145} 146 147SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 148 149int 150linker_add_class(linker_class_t lc) 151{ 152 153 /* 154 * We disallow any class registration past SI_ORDER_ANY 155 * of SI_SUB_KLD. We bump the reference count to keep the 156 * ops from being freed. 157 */ 158 if (linker_no_more_classes == 1) 159 return (EPERM); 160 kobj_class_compile((kobj_class_t) lc); 161 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 162 TAILQ_INSERT_TAIL(&classes, lc, link); 163 return (0); 164} 165 166static void 167linker_file_sysinit(linker_file_t lf) 168{ 169 struct sysinit **start, **stop, **sipp, **xipp, *save; 170 171 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 172 lf->filename)); 173 174 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 175 return; 176 /* 177 * Perform a bubble sort of the system initialization objects by 178 * their subsystem (primary key) and order (secondary key). 179 * 180 * Since some things care about execution order, this is the operation 181 * which ensures continued function. 182 */ 183 for (sipp = start; sipp < stop; sipp++) { 184 for (xipp = sipp + 1; xipp < stop; xipp++) { 185 if ((*sipp)->subsystem < (*xipp)->subsystem || 186 ((*sipp)->subsystem == (*xipp)->subsystem && 187 (*sipp)->order <= (*xipp)->order)) 188 continue; /* skip */ 189 save = *sipp; 190 *sipp = *xipp; 191 *xipp = save; 192 } 193 } 194 195 /* 196 * Traverse the (now) ordered list of system initialization tasks. 197 * Perform each task, and continue on to the next task. 198 */ 199 for (sipp = start; sipp < stop; sipp++) { 200 if ((*sipp)->subsystem == SI_SUB_DUMMY) 201 continue; /* skip dummy task(s) */ 202 203 /* Call function */ 204 (*((*sipp)->func)) ((*sipp)->udata); 205 } 206} 207 208static void 209linker_file_sysuninit(linker_file_t lf) 210{ 211 struct sysinit **start, **stop, **sipp, **xipp, *save; 212 213 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 214 lf->filename)); 215 216 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 217 NULL) != 0) 218 return; 219 220 /* 221 * Perform a reverse bubble sort of the system initialization objects 222 * by their subsystem (primary key) and order (secondary key). 223 * 224 * Since some things care about execution order, this is the operation 225 * which ensures continued function. 226 */ 227 for (sipp = start; sipp < stop; sipp++) { 228 for (xipp = sipp + 1; xipp < stop; xipp++) { 229 if ((*sipp)->subsystem > (*xipp)->subsystem || 230 ((*sipp)->subsystem == (*xipp)->subsystem && 231 (*sipp)->order >= (*xipp)->order)) 232 continue; /* skip */ 233 save = *sipp; 234 *sipp = *xipp; 235 *xipp = save; 236 } 237 } 238 239 /* 240 * Traverse the (now) ordered list of system initialization tasks. 241 * Perform each task, and continue on to the next task. 242 */ 243 for (sipp = start; sipp < stop; sipp++) { 244 if ((*sipp)->subsystem == SI_SUB_DUMMY) 245 continue; /* skip dummy task(s) */ 246 247 /* Call function */ 248 (*((*sipp)->func)) ((*sipp)->udata); 249 } 250} 251 252static void 253linker_file_register_sysctls(linker_file_t lf) 254{ 255 struct sysctl_oid **start, **stop, **oidp; 256 257 KLD_DPF(FILE, 258 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 259 lf->filename)); 260 261 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 262 return; 263 264 for (oidp = start; oidp < stop; oidp++) 265 sysctl_register_oid(*oidp); 266} 267 268static void 269linker_file_unregister_sysctls(linker_file_t lf) 270{ 271 struct sysctl_oid **start, **stop, **oidp; 272 273 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 274 " for %s\n", lf->filename)); 275 276 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 277 return; 278 279 for (oidp = start; oidp < stop; oidp++) 280 sysctl_unregister_oid(*oidp); 281} 282 283static int 284linker_file_register_modules(linker_file_t lf) 285{ 286 struct mod_metadata **start, **stop, **mdp; 287 const moduledata_t *moddata; 288 int first_error, error; 289 290 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 291 " in %s\n", lf->filename)); 292 293 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 294 &stop, 0) != 0) { 295 /* 296 * This fallback should be unnecessary, but if we get booted 297 * from boot2 instead of loader and we are missing our 298 * metadata then we have to try the best we can. 299 */ 300 if (lf == linker_kernel_file) { 301 start = SET_BEGIN(modmetadata_set); 302 stop = SET_LIMIT(modmetadata_set); 303 } else 304 return (0); 305 } 306 first_error = 0; 307 for (mdp = start; mdp < stop; mdp++) { 308 if ((*mdp)->md_type != MDT_MODULE) 309 continue; 310 moddata = (*mdp)->md_data; 311 KLD_DPF(FILE, ("Registering module %s in %s\n", 312 moddata->name, lf->filename)); 313 error = module_register(moddata, lf); 314 if (error) { 315 printf("Module %s failed to register: %d\n", 316 moddata->name, error); 317 if (first_error == 0) 318 first_error = error; 319 } 320 } 321 return (first_error); 322} 323 324static void 325linker_init_kernel_modules(void) 326{ 327 328 linker_file_register_modules(linker_kernel_file); 329} 330 331SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 332 333static int 334linker_load_file(const char *filename, linker_file_t *result) 335{ 336 linker_class_t lc; 337 linker_file_t lf; 338 int foundfile, error; 339 340 /* Refuse to load modules if securelevel raised */ 341 if (securelevel > 0) 342 return (EPERM); 343 344 lf = linker_find_file_by_name(filename); 345 if (lf) { 346 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 347 " incrementing refs\n", filename)); 348 *result = lf; 349 lf->refs++; 350 return (0); 351 } 352 foundfile = 0; 353 error = 0; 354 355 /* 356 * We do not need to protect (lock) classes here because there is 357 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 358 * and there is no class deregistration mechanism at this time. 359 */ 360 TAILQ_FOREACH(lc, &classes, link) { 361 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 362 filename)); 363 error = LINKER_LOAD_FILE(lc, filename, &lf); 364 /* 365 * If we got something other than ENOENT, then it exists but 366 * we cannot load it for some other reason. 367 */ 368 if (error != ENOENT) 369 foundfile = 1; 370 if (lf) { 371 error = linker_file_register_modules(lf); 372 if (error == EEXIST) { 373 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 374 return (error); 375 } 376 linker_file_register_sysctls(lf); 377 linker_file_sysinit(lf); 378 lf->flags |= LINKER_FILE_LINKED; 379 *result = lf; 380 return (0); 381 } 382 } 383 /* 384 * Less than ideal, but tells the user whether it failed to load or 385 * the module was not found. 386 */ 387 if (foundfile) { 388 /* 389 * Format not recognized or otherwise unloadable. 390 * When loading a module that is statically built into 391 * the kernel EEXIST percolates back up as the return 392 * value. Preserve this so that apps like sysinstall 393 * can recognize this special case and not post bogus 394 * dialog boxes. 395 */ 396 if (error != EEXIST) 397 error = ENOEXEC; 398 } else 399 error = ENOENT; /* Nothing found */ 400 return (error); 401} 402 403int 404linker_reference_module(const char *modname, struct mod_depend *verinfo, 405 linker_file_t *result) 406{ 407 modlist_t mod; 408 409 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 410 *result = mod->container; 411 (*result)->refs++; 412 return (0); 413 } 414 415 return (linker_load_module(NULL, modname, NULL, verinfo, result)); 416} 417 418linker_file_t 419linker_find_file_by_name(const char *filename) 420{ 421 linker_file_t lf; 422 char *koname; 423 424 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 425 sprintf(koname, "%s.ko", filename); 426 427 mtx_lock(&kld_mtx); 428 TAILQ_FOREACH(lf, &linker_files, link) { 429 if (strcmp(lf->filename, koname) == 0) 430 break; 431 if (strcmp(lf->filename, filename) == 0) 432 break; 433 } 434 mtx_unlock(&kld_mtx); 435 free(koname, M_LINKER); 436 return (lf); 437} 438 439linker_file_t 440linker_find_file_by_id(int fileid) 441{ 442 linker_file_t lf; 443 444 mtx_lock(&kld_mtx); 445 TAILQ_FOREACH(lf, &linker_files, link) 446 if (lf->id == fileid) 447 break; 448 mtx_unlock(&kld_mtx); 449 return (lf); 450} 451 452int 453linker_file_foreach(linker_predicate_t *predicate, void *context) 454{ 455 linker_file_t lf; 456 int retval = 0; 457 458 mtx_lock(&Giant); 459 TAILQ_FOREACH(lf, &linker_files, link) { 460 retval = predicate(lf, context); 461 if (retval != 0) 462 break; 463 } 464 mtx_unlock(&Giant); 465 return (retval); 466} 467 468linker_file_t 469linker_make_file(const char *pathname, linker_class_t lc) 470{ 471 linker_file_t lf; 472 const char *filename; 473 474 filename = linker_basename(pathname); 475 476 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 477 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 478 if (lf == NULL) 479 return (NULL); 480 lf->refs = 1; 481 lf->userrefs = 0; 482 lf->flags = 0; 483 lf->filename = linker_strdup(filename); 484 LINKER_GET_NEXT_FILE_ID(lf->id); 485 lf->ndeps = 0; 486 lf->deps = NULL; 487 STAILQ_INIT(&lf->common); 488 TAILQ_INIT(&lf->modules); 489 mtx_lock(&kld_mtx); 490 TAILQ_INSERT_TAIL(&linker_files, lf, link); 491 mtx_unlock(&kld_mtx); 492 return (lf); 493} 494 495int 496linker_file_unload(linker_file_t file, int flags) 497{ 498 module_t mod, next; 499 modlist_t ml, nextml; 500 struct common_symbol *cp; 501 int error, i; 502 503 /* Refuse to unload modules if securelevel raised. */ 504 if (securelevel > 0) 505 return (EPERM); 506#ifdef MAC 507 error = mac_check_kld_unload(curthread->td_ucred); 508 if (error) 509 return (error); 510#endif 511 512 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 513 514 /* Easy case of just dropping a reference. */ 515 if (file->refs > 1) { 516 file->refs--; 517 return (0); 518 } 519 520 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 521 " informing modules\n")); 522 523 /* 524 * Inform any modules associated with this file. 525 */ 526 MOD_XLOCK; 527 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 528 next = module_getfnext(mod); 529 MOD_XUNLOCK; 530 531 /* 532 * Give the module a chance to veto the unload. 533 */ 534 if ((error = module_unload(mod, flags)) != 0) { 535 KLD_DPF(FILE, ("linker_file_unload: module %p" 536 " vetoes unload\n", mod)); 537 return (error); 538 } 539 MOD_XLOCK; 540 module_release(mod); 541 } 542 MOD_XUNLOCK; 543 544 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 545 if (ml->container == file) { 546 TAILQ_REMOVE(&found_modules, ml, link); 547 free(ml, M_LINKER); 548 } 549 } 550 551 /* 552 * Don't try to run SYSUNINITs if we are unloaded due to a 553 * link error. 554 */ 555 if (file->flags & LINKER_FILE_LINKED) { 556 linker_file_sysuninit(file); 557 linker_file_unregister_sysctls(file); 558 } 559 mtx_lock(&kld_mtx); 560 TAILQ_REMOVE(&linker_files, file, link); 561 mtx_unlock(&kld_mtx); 562 563 if (file->deps) { 564 for (i = 0; i < file->ndeps; i++) 565 linker_file_unload(file->deps[i], flags); 566 free(file->deps, M_LINKER); 567 file->deps = NULL; 568 } 569 for (cp = STAILQ_FIRST(&file->common); cp; 570 cp = STAILQ_FIRST(&file->common)) { 571 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 572 free(cp, M_LINKER); 573 } 574 575 LINKER_UNLOAD(file); 576 if (file->filename) { 577 free(file->filename, M_LINKER); 578 file->filename = NULL; 579 } 580 kobj_delete((kobj_t) file, M_LINKER); 581 return (0); 582} 583 584static int 585linker_file_add_dependency(linker_file_t file, linker_file_t dep) 586{ 587 linker_file_t *newdeps; 588 589 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 590 M_LINKER, M_WAITOK | M_ZERO); 591 if (newdeps == NULL) 592 return (ENOMEM); 593 594 if (file->deps) { 595 bcopy(file->deps, newdeps, 596 file->ndeps * sizeof(linker_file_t *)); 597 free(file->deps, M_LINKER); 598 } 599 file->deps = newdeps; 600 file->deps[file->ndeps] = dep; 601 file->ndeps++; 602 return (0); 603} 604 605/* 606 * Locate a linker set and its contents. This is a helper function to avoid 607 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 608 */ 609int 610linker_file_lookup_set(linker_file_t file, const char *name, 611 void *firstp, void *lastp, int *countp) 612{ 613 614 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 615} 616 617caddr_t 618linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 619{ 620 c_linker_sym_t sym; 621 linker_symval_t symval; 622 caddr_t address; 623 size_t common_size = 0; 624 int i; 625 626 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 627 file, name, deps)); 628 629 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 630 LINKER_SYMBOL_VALUES(file, sym, &symval); 631 if (symval.value == 0) 632 /* 633 * For commons, first look them up in the 634 * dependencies and only allocate space if not found 635 * there. 636 */ 637 common_size = symval.size; 638 else { 639 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 640 ".value=%p\n", symval.value)); 641 return (symval.value); 642 } 643 } 644 if (deps) { 645 for (i = 0; i < file->ndeps; i++) { 646 address = linker_file_lookup_symbol(file->deps[i], 647 name, 0); 648 if (address) { 649 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 650 " deps value=%p\n", address)); 651 return (address); 652 } 653 } 654 } 655 if (common_size > 0) { 656 /* 657 * This is a common symbol which was not found in the 658 * dependencies. We maintain a simple common symbol table in 659 * the file object. 660 */ 661 struct common_symbol *cp; 662 663 STAILQ_FOREACH(cp, &file->common, link) { 664 if (strcmp(cp->name, name) == 0) { 665 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 666 " old common value=%p\n", cp->address)); 667 return (cp->address); 668 } 669 } 670 /* 671 * Round the symbol size up to align. 672 */ 673 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 674 cp = malloc(sizeof(struct common_symbol) 675 + common_size + strlen(name) + 1, M_LINKER, 676 M_WAITOK | M_ZERO); 677 cp->address = (caddr_t)(cp + 1); 678 cp->name = cp->address + common_size; 679 strcpy(cp->name, name); 680 bzero(cp->address, common_size); 681 STAILQ_INSERT_TAIL(&file->common, cp, link); 682 683 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 684 " value=%p\n", cp->address)); 685 return (cp->address); 686 } 687 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 688 return (0); 689} 690 691#ifdef DDB 692/* 693 * DDB Helpers. DDB has to look across multiple files with their own symbol 694 * tables and string tables. 695 * 696 * Note that we do not obey list locking protocols here. We really don't need 697 * DDB to hang because somebody's got the lock held. We'll take the chance 698 * that the files list is inconsistant instead. 699 */ 700 701int 702linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 703{ 704 linker_file_t lf; 705 706 TAILQ_FOREACH(lf, &linker_files, link) { 707 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 708 return (0); 709 } 710 return (ENOENT); 711} 712 713int 714linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 715{ 716 linker_file_t lf; 717 c_linker_sym_t best, es; 718 u_long diff, bestdiff, off; 719 720 best = 0; 721 off = (uintptr_t)value; 722 bestdiff = off; 723 TAILQ_FOREACH(lf, &linker_files, link) { 724 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 725 continue; 726 if (es != 0 && diff < bestdiff) { 727 best = es; 728 bestdiff = diff; 729 } 730 if (bestdiff == 0) 731 break; 732 } 733 if (best) { 734 *sym = best; 735 *diffp = bestdiff; 736 return (0); 737 } else { 738 *sym = 0; 739 *diffp = off; 740 return (ENOENT); 741 } 742} 743 744int 745linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 746{ 747 linker_file_t lf; 748 749 TAILQ_FOREACH(lf, &linker_files, link) { 750 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 751 return (0); 752 } 753 return (ENOENT); 754} 755#endif 756 757/* 758 * Syscalls. 759 */ 760/* 761 * MPSAFE 762 */ 763int 764kern_kldload(struct thread *td, const char *file, int *fileid) 765{ 766#ifdef HWPMC_HOOKS 767 struct pmckern_map_in pkm; 768#endif 769 const char *kldname, *modname; 770 linker_file_t lf; 771 int error; 772 773 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 774 return (error); 775 776 if ((error = suser(td)) != 0) 777 return (error); 778 779 /* 780 * If file does not contain qualified name or any dot in it 781 * (kldname.ko, or kldname.ver.ko) treat it as interface 782 * name. 783 */ 784 if (index(file, '/') || index(file, '.')) { 785 kldname = file; 786 modname = NULL; 787 } else { 788 kldname = NULL; 789 modname = file; 790 } 791 792 mtx_lock(&Giant); 793 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 794 if (error) 795 goto unlock; 796 797#ifdef HWPMC_HOOKS 798 pkm.pm_file = lf->filename; 799 pkm.pm_address = (uintptr_t) lf->address; 800 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 801#endif 802 lf->userrefs++; 803 if (fileid != NULL) 804 *fileid = lf->id; 805unlock: 806 mtx_unlock(&Giant); 807 return (error); 808} 809 810int 811kldload(struct thread *td, struct kldload_args *uap) 812{ 813 char *pathname = NULL; 814 int error, fileid; 815 816 td->td_retval[0] = -1; 817 818 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 819 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 820 if (error == 0) { 821 error = kern_kldload(td, pathname, &fileid); 822 if (error == 0) 823 td->td_retval[0] = fileid; 824 } 825 free(pathname, M_TEMP); 826 return (error); 827} 828 829/* 830 * MPSAFE 831 */ 832int 833kern_kldunload(struct thread *td, int fileid, int flags) 834{ 835#ifdef HWPMC_HOOKS 836 struct pmckern_map_out pkm; 837#endif 838 linker_file_t lf; 839 int error = 0; 840 841 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 842 return (error); 843 844 if ((error = suser(td)) != 0) 845 return (error); 846 847 mtx_lock(&Giant); 848 lf = linker_find_file_by_id(fileid); 849 if (lf) { 850 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 851 if (lf->userrefs == 0) { 852 /* 853 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 854 */ 855 printf("kldunload: attempt to unload file that was" 856 " loaded by the kernel\n"); 857 error = EBUSY; 858 } else { 859#ifdef HWPMC_HOOKS 860 /* Save data needed by hwpmc(4) before unloading. */ 861 pkm.pm_address = (uintptr_t) lf->address; 862 pkm.pm_size = lf->size; 863#endif 864 lf->userrefs--; 865 error = linker_file_unload(lf, flags); 866 if (error) 867 lf->userrefs++; 868 } 869 } else 870 error = ENOENT; 871 872#ifdef HWPMC_HOOKS 873 if (error == 0) 874 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 875#endif 876 mtx_unlock(&Giant); 877 return (error); 878} 879 880/* 881 * MPSAFE 882 */ 883int 884kldunload(struct thread *td, struct kldunload_args *uap) 885{ 886 887 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 888} 889 890/* 891 * MPSAFE 892 */ 893int 894kldunloadf(struct thread *td, struct kldunloadf_args *uap) 895{ 896 897 if (uap->flags != LINKER_UNLOAD_NORMAL && 898 uap->flags != LINKER_UNLOAD_FORCE) 899 return (EINVAL); 900 return (kern_kldunload(td, uap->fileid, uap->flags)); 901} 902 903/* 904 * MPSAFE 905 */ 906int 907kldfind(struct thread *td, struct kldfind_args *uap) 908{ 909 char *pathname; 910 const char *filename; 911 linker_file_t lf; 912 int error; 913 914#ifdef MAC 915 error = mac_check_kld_stat(td->td_ucred); 916 if (error) 917 return (error); 918#endif 919 920 mtx_lock(&Giant); 921 td->td_retval[0] = -1; 922 923 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 924 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 925 goto out; 926 927 filename = linker_basename(pathname); 928 lf = linker_find_file_by_name(filename); 929 if (lf) 930 td->td_retval[0] = lf->id; 931 else 932 error = ENOENT; 933out: 934 free(pathname, M_TEMP); 935 mtx_unlock(&Giant); 936 return (error); 937} 938 939/* 940 * MPSAFE 941 */ 942int 943kldnext(struct thread *td, struct kldnext_args *uap) 944{ 945 linker_file_t lf; 946 int error = 0; 947 948#ifdef MAC 949 error = mac_check_kld_stat(td->td_ucred); 950 if (error) 951 return (error); 952#endif 953 954 mtx_lock(&Giant); 955 956 if (uap->fileid == 0) { 957 mtx_lock(&kld_mtx); 958 if (TAILQ_FIRST(&linker_files)) 959 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 960 else 961 td->td_retval[0] = 0; 962 mtx_unlock(&kld_mtx); 963 goto out; 964 } 965 lf = linker_find_file_by_id(uap->fileid); 966 if (lf) { 967 if (TAILQ_NEXT(lf, link)) 968 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 969 else 970 td->td_retval[0] = 0; 971 } else 972 error = ENOENT; 973out: 974 mtx_unlock(&Giant); 975 return (error); 976} 977 978/* 979 * MPSAFE 980 */ 981int 982kldstat(struct thread *td, struct kldstat_args *uap) 983{ 984 struct kld_file_stat stat; 985 linker_file_t lf; 986 int error, namelen; 987 988 /* 989 * Check the version of the user's structure. 990 */ 991 error = copyin(uap->stat, &stat, sizeof(struct kld_file_stat)); 992 if (error) 993 return (error); 994 if (stat.version != sizeof(struct kld_file_stat)) 995 return (EINVAL); 996 997#ifdef MAC 998 error = mac_check_kld_stat(td->td_ucred); 999 if (error) 1000 return (error); 1001#endif 1002 1003 mtx_lock(&Giant); 1004 1005 lf = linker_find_file_by_id(uap->fileid); 1006 if (lf == NULL) { 1007 mtx_unlock(&Giant); 1008 return (ENOENT); 1009 } 1010 1011 namelen = strlen(lf->filename) + 1; 1012 if (namelen > MAXPATHLEN) 1013 namelen = MAXPATHLEN; 1014 bcopy(lf->filename, &stat.name[0], namelen); 1015 stat.refs = lf->refs; 1016 stat.id = lf->id; 1017 stat.address = lf->address; 1018 stat.size = lf->size; 1019 mtx_unlock(&Giant); 1020 1021 td->td_retval[0] = 0; 1022 1023 return (copyout(&stat, uap->stat, sizeof(struct kld_file_stat))); 1024} 1025 1026/* 1027 * MPSAFE 1028 */ 1029int 1030kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1031{ 1032 linker_file_t lf; 1033 module_t mp; 1034 int error = 0; 1035 1036#ifdef MAC 1037 error = mac_check_kld_stat(td->td_ucred); 1038 if (error) 1039 return (error); 1040#endif 1041 1042 mtx_lock(&Giant); 1043 lf = linker_find_file_by_id(uap->fileid); 1044 if (lf) { 1045 MOD_SLOCK; 1046 mp = TAILQ_FIRST(&lf->modules); 1047 if (mp != NULL) 1048 td->td_retval[0] = module_getid(mp); 1049 else 1050 td->td_retval[0] = 0; 1051 MOD_SUNLOCK; 1052 } else 1053 error = ENOENT; 1054 mtx_unlock(&Giant); 1055 return (error); 1056} 1057 1058/* 1059 * MPSAFE 1060 */ 1061int 1062kldsym(struct thread *td, struct kldsym_args *uap) 1063{ 1064 char *symstr = NULL; 1065 c_linker_sym_t sym; 1066 linker_symval_t symval; 1067 linker_file_t lf; 1068 struct kld_sym_lookup lookup; 1069 int error = 0; 1070 1071#ifdef MAC 1072 error = mac_check_kld_stat(td->td_ucred); 1073 if (error) 1074 return (error); 1075#endif 1076 1077 mtx_lock(&Giant); 1078 1079 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1080 goto out; 1081 if (lookup.version != sizeof(lookup) || 1082 uap->cmd != KLDSYM_LOOKUP) { 1083 error = EINVAL; 1084 goto out; 1085 } 1086 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1087 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1088 goto out; 1089 if (uap->fileid != 0) { 1090 lf = linker_find_file_by_id(uap->fileid); 1091 if (lf == NULL) { 1092 error = ENOENT; 1093 goto out; 1094 } 1095 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1096 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1097 lookup.symvalue = (uintptr_t) symval.value; 1098 lookup.symsize = symval.size; 1099 error = copyout(&lookup, uap->data, sizeof(lookup)); 1100 } else 1101 error = ENOENT; 1102 } else { 1103 mtx_lock(&kld_mtx); 1104 TAILQ_FOREACH(lf, &linker_files, link) { 1105 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1106 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1107 lookup.symvalue = (uintptr_t)symval.value; 1108 lookup.symsize = symval.size; 1109 error = copyout(&lookup, uap->data, 1110 sizeof(lookup)); 1111 break; 1112 } 1113 } 1114 mtx_unlock(&kld_mtx); 1115 if (lf == NULL) 1116 error = ENOENT; 1117 } 1118out: 1119 if (symstr) 1120 free(symstr, M_TEMP); 1121 mtx_unlock(&Giant); 1122 return (error); 1123} 1124 1125/* 1126 * Preloaded module support 1127 */ 1128 1129static modlist_t 1130modlist_lookup(const char *name, int ver) 1131{ 1132 modlist_t mod; 1133 1134 TAILQ_FOREACH(mod, &found_modules, link) { 1135 if (strcmp(mod->name, name) == 0 && 1136 (ver == 0 || mod->version == ver)) 1137 return (mod); 1138 } 1139 return (NULL); 1140} 1141 1142static modlist_t 1143modlist_lookup2(const char *name, struct mod_depend *verinfo) 1144{ 1145 modlist_t mod, bestmod; 1146 int ver; 1147 1148 if (verinfo == NULL) 1149 return (modlist_lookup(name, 0)); 1150 bestmod = NULL; 1151 TAILQ_FOREACH(mod, &found_modules, link) { 1152 if (strcmp(mod->name, name) != 0) 1153 continue; 1154 ver = mod->version; 1155 if (ver == verinfo->md_ver_preferred) 1156 return (mod); 1157 if (ver >= verinfo->md_ver_minimum && 1158 ver <= verinfo->md_ver_maximum && 1159 (bestmod == NULL || ver > bestmod->version)) 1160 bestmod = mod; 1161 } 1162 return (bestmod); 1163} 1164 1165static modlist_t 1166modlist_newmodule(const char *modname, int version, linker_file_t container) 1167{ 1168 modlist_t mod; 1169 1170 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1171 if (mod == NULL) 1172 panic("no memory for module list"); 1173 mod->container = container; 1174 mod->name = modname; 1175 mod->version = version; 1176 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1177 return (mod); 1178} 1179 1180static void 1181linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1182 struct mod_metadata **stop, int preload) 1183{ 1184 struct mod_metadata *mp, **mdp; 1185 const char *modname; 1186 int ver; 1187 1188 for (mdp = start; mdp < stop; mdp++) { 1189 mp = *mdp; 1190 if (mp->md_type != MDT_VERSION) 1191 continue; 1192 modname = mp->md_cval; 1193 ver = ((struct mod_version *)mp->md_data)->mv_version; 1194 if (modlist_lookup(modname, ver) != NULL) { 1195 printf("module %s already present!\n", modname); 1196 /* XXX what can we do? this is a build error. :-( */ 1197 continue; 1198 } 1199 modlist_newmodule(modname, ver, lf); 1200 } 1201} 1202 1203static void 1204linker_preload(void *arg) 1205{ 1206 caddr_t modptr; 1207 const char *modname, *nmodname; 1208 char *modtype; 1209 linker_file_t lf; 1210 linker_class_t lc; 1211 int error; 1212 linker_file_list_t loaded_files; 1213 linker_file_list_t depended_files; 1214 struct mod_metadata *mp, *nmp; 1215 struct mod_metadata **start, **stop, **mdp, **nmdp; 1216 struct mod_depend *verinfo; 1217 int nver; 1218 int resolves; 1219 modlist_t mod; 1220 struct sysinit **si_start, **si_stop; 1221 1222 TAILQ_INIT(&loaded_files); 1223 TAILQ_INIT(&depended_files); 1224 TAILQ_INIT(&found_modules); 1225 error = 0; 1226 1227 modptr = NULL; 1228 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1229 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1230 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1231 if (modname == NULL) { 1232 printf("Preloaded module at %p does not have a" 1233 " name!\n", modptr); 1234 continue; 1235 } 1236 if (modtype == NULL) { 1237 printf("Preloaded module at %p does not have a type!\n", 1238 modptr); 1239 continue; 1240 } 1241 if (bootverbose) 1242 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1243 modptr); 1244 lf = NULL; 1245 TAILQ_FOREACH(lc, &classes, link) { 1246 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1247 if (!error) 1248 break; 1249 lf = NULL; 1250 } 1251 if (lf) 1252 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1253 } 1254 1255 /* 1256 * First get a list of stuff in the kernel. 1257 */ 1258 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1259 &stop, NULL) == 0) 1260 linker_addmodules(linker_kernel_file, start, stop, 1); 1261 1262 /* 1263 * this is a once-off kinky bubble sort resolve relocation dependency 1264 * requirements 1265 */ 1266restart: 1267 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1268 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1269 &stop, NULL); 1270 /* 1271 * First, look to see if we would successfully link with this 1272 * stuff. 1273 */ 1274 resolves = 1; /* unless we know otherwise */ 1275 if (!error) { 1276 for (mdp = start; mdp < stop; mdp++) { 1277 mp = *mdp; 1278 if (mp->md_type != MDT_DEPEND) 1279 continue; 1280 modname = mp->md_cval; 1281 verinfo = mp->md_data; 1282 for (nmdp = start; nmdp < stop; nmdp++) { 1283 nmp = *nmdp; 1284 if (nmp->md_type != MDT_VERSION) 1285 continue; 1286 nmodname = nmp->md_cval; 1287 if (strcmp(modname, nmodname) == 0) 1288 break; 1289 } 1290 if (nmdp < stop) /* it's a self reference */ 1291 continue; 1292 1293 /* 1294 * ok, the module isn't here yet, we 1295 * are not finished 1296 */ 1297 if (modlist_lookup2(modname, verinfo) == NULL) 1298 resolves = 0; 1299 } 1300 } 1301 /* 1302 * OK, if we found our modules, we can link. So, "provide" 1303 * the modules inside and add it to the end of the link order 1304 * list. 1305 */ 1306 if (resolves) { 1307 if (!error) { 1308 for (mdp = start; mdp < stop; mdp++) { 1309 mp = *mdp; 1310 if (mp->md_type != MDT_VERSION) 1311 continue; 1312 modname = mp->md_cval; 1313 nver = ((struct mod_version *) 1314 mp->md_data)->mv_version; 1315 if (modlist_lookup(modname, 1316 nver) != NULL) { 1317 printf("module %s already" 1318 " present!\n", modname); 1319 linker_file_unload(lf, 1320 LINKER_UNLOAD_FORCE); 1321 TAILQ_REMOVE(&loaded_files, 1322 lf, loaded); 1323 /* we changed tailq next ptr */ 1324 goto restart; 1325 } 1326 modlist_newmodule(modname, nver, lf); 1327 } 1328 } 1329 TAILQ_REMOVE(&loaded_files, lf, loaded); 1330 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1331 /* 1332 * Since we provided modules, we need to restart the 1333 * sort so that the previous files that depend on us 1334 * have a chance. Also, we've busted the tailq next 1335 * pointer with the REMOVE. 1336 */ 1337 goto restart; 1338 } 1339 } 1340 1341 /* 1342 * At this point, we check to see what could not be resolved.. 1343 */ 1344 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1345 printf("KLD file %s is missing dependencies\n", lf->filename); 1346 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1347 TAILQ_REMOVE(&loaded_files, lf, loaded); 1348 } 1349 1350 /* 1351 * We made it. Finish off the linking in the order we determined. 1352 */ 1353 TAILQ_FOREACH(lf, &depended_files, loaded) { 1354 if (linker_kernel_file) { 1355 linker_kernel_file->refs++; 1356 error = linker_file_add_dependency(lf, 1357 linker_kernel_file); 1358 if (error) 1359 panic("cannot add dependency"); 1360 } 1361 lf->userrefs++; /* so we can (try to) kldunload it */ 1362 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1363 &stop, NULL); 1364 if (!error) { 1365 for (mdp = start; mdp < stop; mdp++) { 1366 mp = *mdp; 1367 if (mp->md_type != MDT_DEPEND) 1368 continue; 1369 modname = mp->md_cval; 1370 verinfo = mp->md_data; 1371 mod = modlist_lookup2(modname, verinfo); 1372 /* Don't count self-dependencies */ 1373 if (lf == mod->container) 1374 continue; 1375 mod->container->refs++; 1376 error = linker_file_add_dependency(lf, 1377 mod->container); 1378 if (error) 1379 panic("cannot add dependency"); 1380 } 1381 } 1382 /* 1383 * Now do relocation etc using the symbol search paths 1384 * established by the dependencies 1385 */ 1386 error = LINKER_LINK_PRELOAD_FINISH(lf); 1387 if (error) { 1388 printf("KLD file %s - could not finalize loading\n", 1389 lf->filename); 1390 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1391 continue; 1392 } 1393 linker_file_register_modules(lf); 1394 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1395 &si_stop, NULL) == 0) 1396 sysinit_add(si_start, si_stop); 1397 linker_file_register_sysctls(lf); 1398 lf->flags |= LINKER_FILE_LINKED; 1399 } 1400 /* woohoo! we made it! */ 1401} 1402 1403SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1404 1405/* 1406 * Search for a not-loaded module by name. 1407 * 1408 * Modules may be found in the following locations: 1409 * 1410 * - preloaded (result is just the module name) - on disk (result is full path 1411 * to module) 1412 * 1413 * If the module name is qualified in any way (contains path, etc.) the we 1414 * simply return a copy of it. 1415 * 1416 * The search path can be manipulated via sysctl. Note that we use the ';' 1417 * character as a separator to be consistent with the bootloader. 1418 */ 1419 1420static char linker_hintfile[] = "linker.hints"; 1421static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1422 1423SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1424 sizeof(linker_path), "module load search path"); 1425 1426TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1427 1428static char *linker_ext_list[] = { 1429 "", 1430 ".ko", 1431 NULL 1432}; 1433 1434/* 1435 * Check if file actually exists either with or without extension listed in 1436 * the linker_ext_list. (probably should be generic for the rest of the 1437 * kernel) 1438 */ 1439static char * 1440linker_lookup_file(const char *path, int pathlen, const char *name, 1441 int namelen, struct vattr *vap) 1442{ 1443 struct nameidata nd; 1444 struct thread *td = curthread; /* XXX */ 1445 char *result, **cpp, *sep; 1446 int error, len, extlen, reclen, flags; 1447 enum vtype type; 1448 1449 extlen = 0; 1450 for (cpp = linker_ext_list; *cpp; cpp++) { 1451 len = strlen(*cpp); 1452 if (len > extlen) 1453 extlen = len; 1454 } 1455 extlen++; /* trailing '\0' */ 1456 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1457 1458 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1459 result = malloc(reclen, M_LINKER, M_WAITOK); 1460 for (cpp = linker_ext_list; *cpp; cpp++) { 1461 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1462 namelen, name, *cpp); 1463 /* 1464 * Attempt to open the file, and return the path if 1465 * we succeed and it's a regular file. 1466 */ 1467 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1468 flags = FREAD; 1469 error = vn_open(&nd, &flags, 0, -1); 1470 if (error == 0) { 1471 NDFREE(&nd, NDF_ONLY_PNBUF); 1472 type = nd.ni_vp->v_type; 1473 if (vap) 1474 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1475 VOP_UNLOCK(nd.ni_vp, 0, td); 1476 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1477 if (type == VREG) 1478 return (result); 1479 } 1480 } 1481 free(result, M_LINKER); 1482 return (NULL); 1483} 1484 1485#define INT_ALIGN(base, ptr) ptr = \ 1486 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1487 1488/* 1489 * Lookup KLD which contains requested module in the "linker.hints" file. If 1490 * version specification is available, then try to find the best KLD. 1491 * Otherwise just find the latest one. 1492 */ 1493static char * 1494linker_hints_lookup(const char *path, int pathlen, const char *modname, 1495 int modnamelen, struct mod_depend *verinfo) 1496{ 1497 struct thread *td = curthread; /* XXX */ 1498 struct ucred *cred = td ? td->td_ucred : NULL; 1499 struct nameidata nd; 1500 struct vattr vattr, mattr; 1501 u_char *hints = NULL; 1502 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1503 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1504 1505 result = NULL; 1506 bestver = found = 0; 1507 1508 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1509 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1510 strlen(sep) + 1; 1511 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1512 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1513 linker_hintfile); 1514 1515 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1516 flags = FREAD; 1517 error = vn_open(&nd, &flags, 0, -1); 1518 if (error) 1519 goto bad; 1520 NDFREE(&nd, NDF_ONLY_PNBUF); 1521 if (nd.ni_vp->v_type != VREG) 1522 goto bad; 1523 best = cp = NULL; 1524 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1525 if (error) 1526 goto bad; 1527 /* 1528 * XXX: we need to limit this number to some reasonable value 1529 */ 1530 if (vattr.va_size > 100 * 1024) { 1531 printf("hints file too large %ld\n", (long)vattr.va_size); 1532 goto bad; 1533 } 1534 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1535 if (hints == NULL) 1536 goto bad; 1537 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1538 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1539 if (error) 1540 goto bad; 1541 VOP_UNLOCK(nd.ni_vp, 0, td); 1542 vn_close(nd.ni_vp, FREAD, cred, td); 1543 nd.ni_vp = NULL; 1544 if (reclen != 0) { 1545 printf("can't read %d\n", reclen); 1546 goto bad; 1547 } 1548 intp = (int *)hints; 1549 ival = *intp++; 1550 if (ival != LINKER_HINTS_VERSION) { 1551 printf("hints file version mismatch %d\n", ival); 1552 goto bad; 1553 } 1554 bufend = hints + vattr.va_size; 1555 recptr = (u_char *)intp; 1556 clen = blen = 0; 1557 while (recptr < bufend && !found) { 1558 intp = (int *)recptr; 1559 reclen = *intp++; 1560 ival = *intp++; 1561 cp = (char *)intp; 1562 switch (ival) { 1563 case MDT_VERSION: 1564 clen = *cp++; 1565 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1566 break; 1567 cp += clen; 1568 INT_ALIGN(hints, cp); 1569 ival = *(int *)cp; 1570 cp += sizeof(int); 1571 clen = *cp++; 1572 if (verinfo == NULL || 1573 ival == verinfo->md_ver_preferred) { 1574 found = 1; 1575 break; 1576 } 1577 if (ival >= verinfo->md_ver_minimum && 1578 ival <= verinfo->md_ver_maximum && 1579 ival > bestver) { 1580 bestver = ival; 1581 best = cp; 1582 blen = clen; 1583 } 1584 break; 1585 default: 1586 break; 1587 } 1588 recptr += reclen + sizeof(int); 1589 } 1590 /* 1591 * Finally check if KLD is in the place 1592 */ 1593 if (found) 1594 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1595 else if (best) 1596 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1597 1598 /* 1599 * KLD is newer than hints file. What we should do now? 1600 */ 1601 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1602 printf("warning: KLD '%s' is newer than the linker.hints" 1603 " file\n", result); 1604bad: 1605 free(pathbuf, M_LINKER); 1606 if (hints) 1607 free(hints, M_TEMP); 1608 if (nd.ni_vp != NULL) { 1609 VOP_UNLOCK(nd.ni_vp, 0, td); 1610 vn_close(nd.ni_vp, FREAD, cred, td); 1611 } 1612 /* 1613 * If nothing found or hints is absent - fallback to the old 1614 * way by using "kldname[.ko]" as module name. 1615 */ 1616 if (!found && !bestver && result == NULL) 1617 result = linker_lookup_file(path, pathlen, modname, 1618 modnamelen, NULL); 1619 return (result); 1620} 1621 1622/* 1623 * Lookup KLD which contains requested module in the all directories. 1624 */ 1625static char * 1626linker_search_module(const char *modname, int modnamelen, 1627 struct mod_depend *verinfo) 1628{ 1629 char *cp, *ep, *result; 1630 1631 /* 1632 * traverse the linker path 1633 */ 1634 for (cp = linker_path; *cp; cp = ep + 1) { 1635 /* find the end of this component */ 1636 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1637 result = linker_hints_lookup(cp, ep - cp, modname, 1638 modnamelen, verinfo); 1639 if (result != NULL) 1640 return (result); 1641 if (*ep == 0) 1642 break; 1643 } 1644 return (NULL); 1645} 1646 1647/* 1648 * Search for module in all directories listed in the linker_path. 1649 */ 1650static char * 1651linker_search_kld(const char *name) 1652{ 1653 char *cp, *ep, *result; 1654 int len; 1655 1656 /* qualified at all? */ 1657 if (index(name, '/')) 1658 return (linker_strdup(name)); 1659 1660 /* traverse the linker path */ 1661 len = strlen(name); 1662 for (ep = linker_path; *ep; ep++) { 1663 cp = ep; 1664 /* find the end of this component */ 1665 for (; *ep != 0 && *ep != ';'; ep++); 1666 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1667 if (result != NULL) 1668 return (result); 1669 } 1670 return (NULL); 1671} 1672 1673static const char * 1674linker_basename(const char *path) 1675{ 1676 const char *filename; 1677 1678 filename = rindex(path, '/'); 1679 if (filename == NULL) 1680 return path; 1681 if (filename[1]) 1682 filename++; 1683 return (filename); 1684} 1685 1686#ifdef HWPMC_HOOKS 1687 1688struct hwpmc_context { 1689 int nobjects; 1690 int nmappings; 1691 struct pmckern_map_in *kobase; 1692}; 1693 1694static int 1695linker_hwpmc_list_object(linker_file_t lf, void *arg) 1696{ 1697 struct hwpmc_context *hc; 1698 1699 hc = arg; 1700 1701 /* If we run out of mappings, fail. */ 1702 if (hc->nobjects >= hc->nmappings) 1703 return (1); 1704 1705 /* Save the info for this linker file. */ 1706 hc->kobase[hc->nobjects].pm_file = lf->filename; 1707 hc->kobase[hc->nobjects].pm_address = (uintptr_t)lf->address; 1708 hc->nobjects++; 1709 return (0); 1710} 1711 1712/* 1713 * Inform hwpmc about the set of kernel modules currently loaded. 1714 */ 1715void * 1716linker_hwpmc_list_objects(void) 1717{ 1718 struct hwpmc_context hc; 1719 1720 hc.nmappings = 15; /* a reasonable default */ 1721 1722 retry: 1723 /* allocate nmappings+1 entries */ 1724 MALLOC(hc.kobase, struct pmckern_map_in *, 1725 (hc.nmappings + 1) * sizeof(struct pmckern_map_in), M_LINKER, 1726 M_WAITOK | M_ZERO); 1727 1728 hc.nobjects = 0; 1729 if (linker_file_foreach(linker_hwpmc_list_object, &hc) != 0) { 1730 hc.nmappings = hc.nobjects; 1731 FREE(hc.kobase, M_LINKER); 1732 goto retry; 1733 } 1734 1735 KASSERT(hc.nobjects > 0, ("linker_hpwmc_list_objects: no kernel " 1736 "objects?")); 1737 1738 /* The last entry of the malloced area comprises of all zeros. */ 1739 KASSERT(hc.kobase[hc.nobjects].pm_file == NULL, 1740 ("linker_hwpmc_list_objects: last object not NULL")); 1741 1742 return ((void *)hc.kobase); 1743} 1744#endif 1745 1746/* 1747 * Find a file which contains given module and load it, if "parent" is not 1748 * NULL, register a reference to it. 1749 */ 1750static int 1751linker_load_module(const char *kldname, const char *modname, 1752 struct linker_file *parent, struct mod_depend *verinfo, 1753 struct linker_file **lfpp) 1754{ 1755 linker_file_t lfdep; 1756 const char *filename; 1757 char *pathname; 1758 int error; 1759 1760 if (modname == NULL) { 1761 /* 1762 * We have to load KLD 1763 */ 1764 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1765 " is not NULL")); 1766 pathname = linker_search_kld(kldname); 1767 } else { 1768 if (modlist_lookup2(modname, verinfo) != NULL) 1769 return (EEXIST); 1770 if (kldname != NULL) 1771 pathname = linker_strdup(kldname); 1772 else if (rootvnode == NULL) 1773 pathname = NULL; 1774 else 1775 /* 1776 * Need to find a KLD with required module 1777 */ 1778 pathname = linker_search_module(modname, 1779 strlen(modname), verinfo); 1780 } 1781 if (pathname == NULL) 1782 return (ENOENT); 1783 1784 /* 1785 * Can't load more than one file with the same basename XXX: 1786 * Actually it should be possible to have multiple KLDs with 1787 * the same basename but different path because they can 1788 * provide different versions of the same modules. 1789 */ 1790 filename = linker_basename(pathname); 1791 if (linker_find_file_by_name(filename)) 1792 error = EEXIST; 1793 else do { 1794 error = linker_load_file(pathname, &lfdep); 1795 if (error) 1796 break; 1797 if (modname && verinfo && 1798 modlist_lookup2(modname, verinfo) == NULL) { 1799 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1800 error = ENOENT; 1801 break; 1802 } 1803 if (parent) { 1804 error = linker_file_add_dependency(parent, lfdep); 1805 if (error) 1806 break; 1807 } 1808 if (lfpp) 1809 *lfpp = lfdep; 1810 } while (0); 1811 free(pathname, M_LINKER); 1812 return (error); 1813} 1814 1815/* 1816 * This routine is responsible for finding dependencies of userland initiated 1817 * kldload(2)'s of files. 1818 */ 1819int 1820linker_load_dependencies(linker_file_t lf) 1821{ 1822 linker_file_t lfdep; 1823 struct mod_metadata **start, **stop, **mdp, **nmdp; 1824 struct mod_metadata *mp, *nmp; 1825 struct mod_depend *verinfo; 1826 modlist_t mod; 1827 const char *modname, *nmodname; 1828 int ver, error = 0, count; 1829 1830 /* 1831 * All files are dependant on /kernel. 1832 */ 1833 if (linker_kernel_file) { 1834 linker_kernel_file->refs++; 1835 error = linker_file_add_dependency(lf, linker_kernel_file); 1836 if (error) 1837 return (error); 1838 } 1839 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1840 &count) != 0) 1841 return (0); 1842 for (mdp = start; mdp < stop; mdp++) { 1843 mp = *mdp; 1844 if (mp->md_type != MDT_VERSION) 1845 continue; 1846 modname = mp->md_cval; 1847 ver = ((struct mod_version *)mp->md_data)->mv_version; 1848 mod = modlist_lookup(modname, ver); 1849 if (mod != NULL) { 1850 printf("interface %s.%d already present in the KLD" 1851 " '%s'!\n", modname, ver, 1852 mod->container->filename); 1853 return (EEXIST); 1854 } 1855 } 1856 1857 for (mdp = start; mdp < stop; mdp++) { 1858 mp = *mdp; 1859 if (mp->md_type != MDT_DEPEND) 1860 continue; 1861 modname = mp->md_cval; 1862 verinfo = mp->md_data; 1863 nmodname = NULL; 1864 for (nmdp = start; nmdp < stop; nmdp++) { 1865 nmp = *nmdp; 1866 if (nmp->md_type != MDT_VERSION) 1867 continue; 1868 nmodname = nmp->md_cval; 1869 if (strcmp(modname, nmodname) == 0) 1870 break; 1871 } 1872 if (nmdp < stop)/* early exit, it's a self reference */ 1873 continue; 1874 mod = modlist_lookup2(modname, verinfo); 1875 if (mod) { /* woohoo, it's loaded already */ 1876 lfdep = mod->container; 1877 lfdep->refs++; 1878 error = linker_file_add_dependency(lf, lfdep); 1879 if (error) 1880 break; 1881 continue; 1882 } 1883 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1884 if (error) { 1885 printf("KLD %s: depends on %s - not available\n", 1886 lf->filename, modname); 1887 break; 1888 } 1889 } 1890 1891 if (error) 1892 return (error); 1893 linker_addmodules(lf, start, stop, 0); 1894 return (error); 1895} 1896 1897static int 1898sysctl_kern_function_list_iterate(const char *name, void *opaque) 1899{ 1900 struct sysctl_req *req; 1901 1902 req = opaque; 1903 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1904} 1905 1906/* 1907 * Export a nul-separated, double-nul-terminated list of all function names 1908 * in the kernel. 1909 */ 1910static int 1911sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1912{ 1913 linker_file_t lf; 1914 int error; 1915 1916#ifdef MAC 1917 error = mac_check_kld_stat(req->td->td_ucred); 1918 if (error) 1919 return (error); 1920#endif 1921 error = sysctl_wire_old_buffer(req, 0); 1922 if (error != 0) 1923 return (error); 1924 mtx_lock(&kld_mtx); 1925 TAILQ_FOREACH(lf, &linker_files, link) { 1926 error = LINKER_EACH_FUNCTION_NAME(lf, 1927 sysctl_kern_function_list_iterate, req); 1928 if (error) { 1929 mtx_unlock(&kld_mtx); 1930 return (error); 1931 } 1932 } 1933 mtx_unlock(&kld_mtx); 1934 return (SYSCTL_OUT(req, "", 1)); 1935} 1936 1937SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1938 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 1939