kern_linker.c revision 146733
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 146733 2005-05-28 23:20:05Z pjd $"); 29 30#include "opt_ddb.h" 31#include "opt_mac.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/proc.h> 40#include <sys/lock.h> 41#include <sys/mutex.h> 42#include <sys/sx.h> 43#include <sys/mac.h> 44#include <sys/module.h> 45#include <sys/linker.h> 46#include <sys/fcntl.h> 47#include <sys/libkern.h> 48#include <sys/namei.h> 49#include <sys/vnode.h> 50#include <sys/sysctl.h> 51 52#include "linker_if.h" 53 54#ifdef KLD_DEBUG 55int kld_debug = 0; 56#endif 57 58/* 59 * static char *linker_search_path(const char *name, struct mod_depend 60 * *verinfo); 61 */ 62static const char *linker_basename(const char *path); 63 64/* Metadata from the static kernel */ 65SET_DECLARE(modmetadata_set, struct mod_metadata); 66 67MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 68 69linker_file_t linker_kernel_file; 70 71static struct mtx kld_mtx; /* kernel linker mutex */ 72 73static linker_class_list_t classes; 74static linker_file_list_t linker_files; 75static int next_file_id = 1; 76static int linker_no_more_classes = 0; 77 78#define LINKER_GET_NEXT_FILE_ID(a) do { \ 79 linker_file_t lftmp; \ 80 \ 81retry: \ 82 mtx_lock(&kld_mtx); \ 83 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 84 if (next_file_id == lftmp->id) { \ 85 next_file_id++; \ 86 mtx_unlock(&kld_mtx); \ 87 goto retry; \ 88 } \ 89 } \ 90 (a) = next_file_id; \ 91 mtx_unlock(&kld_mtx); /* Hold for safe read of id variable */ \ 92} while(0) 93 94 95/* XXX wrong name; we're looking at version provision tags here, not modules */ 96typedef TAILQ_HEAD(, modlist) modlisthead_t; 97struct modlist { 98 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 99 linker_file_t container; 100 const char *name; 101 int version; 102}; 103typedef struct modlist *modlist_t; 104static modlisthead_t found_modules; 105 106static modlist_t modlist_lookup2(const char *name, 107 struct mod_depend *verinfo); 108 109static char * 110linker_strdup(const char *str) 111{ 112 char *result; 113 114 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 115 strcpy(result, str); 116 return (result); 117} 118 119static void 120linker_init(void *arg) 121{ 122 123 mtx_init(&kld_mtx, "kernel linker", NULL, MTX_DEF); 124 TAILQ_INIT(&classes); 125 TAILQ_INIT(&linker_files); 126} 127 128SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 129 130static void 131linker_stop_class_add(void *arg) 132{ 133 134 linker_no_more_classes = 1; 135} 136 137SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 138 139int 140linker_add_class(linker_class_t lc) 141{ 142 143 /* 144 * We disallow any class registration past SI_ORDER_ANY 145 * of SI_SUB_KLD. We bump the reference count to keep the 146 * ops from being freed. 147 */ 148 if (linker_no_more_classes == 1) 149 return (EPERM); 150 kobj_class_compile((kobj_class_t) lc); 151 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 152 TAILQ_INSERT_TAIL(&classes, lc, link); 153 return (0); 154} 155 156static void 157linker_file_sysinit(linker_file_t lf) 158{ 159 struct sysinit **start, **stop, **sipp, **xipp, *save; 160 161 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 162 lf->filename)); 163 164 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 165 return; 166 /* 167 * Perform a bubble sort of the system initialization objects by 168 * their subsystem (primary key) and order (secondary key). 169 * 170 * Since some things care about execution order, this is the operation 171 * which ensures continued function. 172 */ 173 for (sipp = start; sipp < stop; sipp++) { 174 for (xipp = sipp + 1; xipp < stop; xipp++) { 175 if ((*sipp)->subsystem < (*xipp)->subsystem || 176 ((*sipp)->subsystem == (*xipp)->subsystem && 177 (*sipp)->order <= (*xipp)->order)) 178 continue; /* skip */ 179 save = *sipp; 180 *sipp = *xipp; 181 *xipp = save; 182 } 183 } 184 185 /* 186 * Traverse the (now) ordered list of system initialization tasks. 187 * Perform each task, and continue on to the next task. 188 */ 189 for (sipp = start; sipp < stop; sipp++) { 190 if ((*sipp)->subsystem == SI_SUB_DUMMY) 191 continue; /* skip dummy task(s) */ 192 193 /* Call function */ 194 (*((*sipp)->func)) ((*sipp)->udata); 195 } 196} 197 198static void 199linker_file_sysuninit(linker_file_t lf) 200{ 201 struct sysinit **start, **stop, **sipp, **xipp, *save; 202 203 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 204 lf->filename)); 205 206 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 207 NULL) != 0) 208 return; 209 210 /* 211 * Perform a reverse bubble sort of the system initialization objects 212 * by their subsystem (primary key) and order (secondary key). 213 * 214 * Since some things care about execution order, this is the operation 215 * which ensures continued function. 216 */ 217 for (sipp = start; sipp < stop; sipp++) { 218 for (xipp = sipp + 1; xipp < stop; xipp++) { 219 if ((*sipp)->subsystem > (*xipp)->subsystem || 220 ((*sipp)->subsystem == (*xipp)->subsystem && 221 (*sipp)->order >= (*xipp)->order)) 222 continue; /* skip */ 223 save = *sipp; 224 *sipp = *xipp; 225 *xipp = save; 226 } 227 } 228 229 /* 230 * Traverse the (now) ordered list of system initialization tasks. 231 * Perform each task, and continue on to the next task. 232 */ 233 for (sipp = start; sipp < stop; sipp++) { 234 if ((*sipp)->subsystem == SI_SUB_DUMMY) 235 continue; /* skip dummy task(s) */ 236 237 /* Call function */ 238 (*((*sipp)->func)) ((*sipp)->udata); 239 } 240} 241 242static void 243linker_file_register_sysctls(linker_file_t lf) 244{ 245 struct sysctl_oid **start, **stop, **oidp; 246 247 KLD_DPF(FILE, 248 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 249 lf->filename)); 250 251 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 252 return; 253 254 for (oidp = start; oidp < stop; oidp++) 255 sysctl_register_oid(*oidp); 256} 257 258static void 259linker_file_unregister_sysctls(linker_file_t lf) 260{ 261 struct sysctl_oid **start, **stop, **oidp; 262 263 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 264 " for %s\n", lf->filename)); 265 266 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 267 return; 268 269 for (oidp = start; oidp < stop; oidp++) 270 sysctl_unregister_oid(*oidp); 271} 272 273static int 274linker_file_register_modules(linker_file_t lf) 275{ 276 struct mod_metadata **start, **stop, **mdp; 277 const moduledata_t *moddata; 278 int first_error, error; 279 280 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 281 " in %s\n", lf->filename)); 282 283 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 284 &stop, 0) != 0) { 285 /* 286 * This fallback should be unnecessary, but if we get booted 287 * from boot2 instead of loader and we are missing our 288 * metadata then we have to try the best we can. 289 */ 290 if (lf == linker_kernel_file) { 291 start = SET_BEGIN(modmetadata_set); 292 stop = SET_LIMIT(modmetadata_set); 293 } else 294 return (0); 295 } 296 first_error = 0; 297 for (mdp = start; mdp < stop; mdp++) { 298 if ((*mdp)->md_type != MDT_MODULE) 299 continue; 300 moddata = (*mdp)->md_data; 301 KLD_DPF(FILE, ("Registering module %s in %s\n", 302 moddata->name, lf->filename)); 303 error = module_register(moddata, lf); 304 if (error) { 305 printf("Module %s failed to register: %d\n", 306 moddata->name, error); 307 if (first_error == 0) 308 first_error = error; 309 } 310 } 311 return (first_error); 312} 313 314static void 315linker_init_kernel_modules(void) 316{ 317 318 linker_file_register_modules(linker_kernel_file); 319} 320 321SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 322 323static int 324linker_load_file(const char *filename, linker_file_t *result) 325{ 326 linker_class_t lc; 327 linker_file_t lf; 328 int foundfile, error = 0; 329 330 /* Refuse to load modules if securelevel raised */ 331 if (securelevel > 0) 332 return (EPERM); 333 334 lf = linker_find_file_by_name(filename); 335 if (lf) { 336 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 337 " incrementing refs\n", filename)); 338 *result = lf; 339 lf->refs++; 340 goto out; 341 } 342 lf = NULL; 343 foundfile = 0; 344 345 /* 346 * We do not need to protect (lock) classes here because there is 347 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 348 * and there is no class deregistration mechanism at this time. 349 */ 350 TAILQ_FOREACH(lc, &classes, link) { 351 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 352 filename)); 353 error = LINKER_LOAD_FILE(lc, filename, &lf); 354 /* 355 * If we got something other than ENOENT, then it exists but 356 * we cannot load it for some other reason. 357 */ 358 if (error != ENOENT) 359 foundfile = 1; 360 if (lf) { 361 error = linker_file_register_modules(lf); 362 if (error == EEXIST) { 363 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 364 goto out; 365 } 366 linker_file_register_sysctls(lf); 367 linker_file_sysinit(lf); 368 lf->flags |= LINKER_FILE_LINKED; 369 *result = lf; 370 error = 0; 371 goto out; 372 } 373 } 374 /* 375 * Less than ideal, but tells the user whether it failed to load or 376 * the module was not found. 377 */ 378 if (foundfile) { 379 /* 380 * Format not recognized or otherwise unloadable. 381 * When loading a module that is statically built into 382 * the kernel EEXIST percolates back up as the return 383 * value. Preserve this so that apps like sysinstall 384 * can recognize this special case and not post bogus 385 * dialog boxes. 386 */ 387 if (error != EEXIST) 388 error = ENOEXEC; 389 } else 390 error = ENOENT; /* Nothing found */ 391out: 392 return (error); 393} 394 395int 396linker_reference_module(const char *modname, struct mod_depend *verinfo, 397 linker_file_t *result) 398{ 399 modlist_t mod; 400 401 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 402 *result = mod->container; 403 (*result)->refs++; 404 return (0); 405 } 406 407 return (linker_load_module(NULL, modname, NULL, verinfo, result)); 408} 409 410linker_file_t 411linker_find_file_by_name(const char *filename) 412{ 413 linker_file_t lf = 0; 414 char *koname; 415 416 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 417 if (koname == NULL) 418 goto out; 419 sprintf(koname, "%s.ko", filename); 420 421 mtx_lock(&kld_mtx); 422 TAILQ_FOREACH(lf, &linker_files, link) { 423 if (strcmp(lf->filename, koname) == 0) 424 break; 425 if (strcmp(lf->filename, filename) == 0) 426 break; 427 } 428 mtx_unlock(&kld_mtx); 429out: 430 if (koname) 431 free(koname, M_LINKER); 432 return (lf); 433} 434 435linker_file_t 436linker_find_file_by_id(int fileid) 437{ 438 linker_file_t lf = 0; 439 440 mtx_lock(&kld_mtx); 441 TAILQ_FOREACH(lf, &linker_files, link) 442 if (lf->id == fileid) 443 break; 444 mtx_unlock(&kld_mtx); 445 return (lf); 446} 447 448linker_file_t 449linker_make_file(const char *pathname, linker_class_t lc) 450{ 451 linker_file_t lf; 452 const char *filename; 453 454 lf = NULL; 455 filename = linker_basename(pathname); 456 457 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 458 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 459 if (lf == NULL) 460 goto out; 461 lf->refs = 1; 462 lf->userrefs = 0; 463 lf->flags = 0; 464 lf->filename = linker_strdup(filename); 465 LINKER_GET_NEXT_FILE_ID(lf->id); 466 lf->ndeps = 0; 467 lf->deps = NULL; 468 STAILQ_INIT(&lf->common); 469 TAILQ_INIT(&lf->modules); 470 mtx_lock(&kld_mtx); 471 TAILQ_INSERT_TAIL(&linker_files, lf, link); 472 mtx_unlock(&kld_mtx); 473out: 474 return (lf); 475} 476 477int 478linker_file_unload(linker_file_t file, int flags) 479{ 480 module_t mod, next; 481 modlist_t ml, nextml; 482 struct common_symbol *cp; 483 int error, i; 484 485 error = 0; 486 487 /* Refuse to unload modules if securelevel raised. */ 488 if (securelevel > 0) 489 return (EPERM); 490#ifdef MAC 491 error = mac_check_kld_unload(curthread->td_ucred); 492 if (error) 493 return (error); 494#endif 495 496 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 497 if (file->refs == 1) { 498 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 499 " informing modules\n")); 500 501 /* 502 * Inform any modules associated with this file. 503 */ 504 MOD_XLOCK; 505 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 506 next = module_getfnext(mod); 507 MOD_XUNLOCK; 508 509 /* 510 * Give the module a chance to veto the unload. 511 */ 512 if ((error = module_unload(mod, flags)) != 0) { 513 KLD_DPF(FILE, ("linker_file_unload: module %p" 514 " vetoes unload\n", mod)); 515 goto out; 516 } else 517 MOD_XLOCK; 518 module_release(mod); 519 } 520 MOD_XUNLOCK; 521 } 522 file->refs--; 523 if (file->refs > 0) { 524 goto out; 525 } 526 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 527 nextml = TAILQ_NEXT(ml, link); 528 if (ml->container == file) { 529 TAILQ_REMOVE(&found_modules, ml, link); 530 free(ml, M_LINKER); 531 } 532 } 533 534 /* 535 * Don't try to run SYSUNINITs if we are unloaded due to a 536 * link error. 537 */ 538 if (file->flags & LINKER_FILE_LINKED) { 539 linker_file_sysuninit(file); 540 linker_file_unregister_sysctls(file); 541 } 542 mtx_lock(&kld_mtx); 543 TAILQ_REMOVE(&linker_files, file, link); 544 mtx_unlock(&kld_mtx); 545 546 if (file->deps) { 547 for (i = 0; i < file->ndeps; i++) 548 linker_file_unload(file->deps[i], flags); 549 free(file->deps, M_LINKER); 550 file->deps = NULL; 551 } 552 for (cp = STAILQ_FIRST(&file->common); cp; 553 cp = STAILQ_FIRST(&file->common)) { 554 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 555 free(cp, M_LINKER); 556 } 557 558 LINKER_UNLOAD(file); 559 if (file->filename) { 560 free(file->filename, M_LINKER); 561 file->filename = NULL; 562 } 563 kobj_delete((kobj_t) file, M_LINKER); 564out: 565 return (error); 566} 567 568int 569linker_file_add_dependency(linker_file_t file, linker_file_t dep) 570{ 571 linker_file_t *newdeps; 572 573 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 574 M_LINKER, M_WAITOK | M_ZERO); 575 if (newdeps == NULL) 576 return (ENOMEM); 577 578 if (file->deps) { 579 bcopy(file->deps, newdeps, 580 file->ndeps * sizeof(linker_file_t *)); 581 free(file->deps, M_LINKER); 582 } 583 file->deps = newdeps; 584 file->deps[file->ndeps] = dep; 585 file->ndeps++; 586 return (0); 587} 588 589/* 590 * Locate a linker set and its contents. This is a helper function to avoid 591 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 592 */ 593int 594linker_file_lookup_set(linker_file_t file, const char *name, 595 void *firstp, void *lastp, int *countp) 596{ 597 598 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 599} 600 601caddr_t 602linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 603{ 604 c_linker_sym_t sym; 605 linker_symval_t symval; 606 caddr_t address; 607 size_t common_size = 0; 608 int i; 609 610 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 611 file, name, deps)); 612 613 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 614 LINKER_SYMBOL_VALUES(file, sym, &symval); 615 if (symval.value == 0) 616 /* 617 * For commons, first look them up in the 618 * dependencies and only allocate space if not found 619 * there. 620 */ 621 common_size = symval.size; 622 else { 623 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 624 ".value=%p\n", symval.value)); 625 return (symval.value); 626 } 627 } 628 if (deps) { 629 for (i = 0; i < file->ndeps; i++) { 630 address = linker_file_lookup_symbol(file->deps[i], 631 name, 0); 632 if (address) { 633 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 634 " deps value=%p\n", address)); 635 return (address); 636 } 637 } 638 } 639 if (common_size > 0) { 640 /* 641 * This is a common symbol which was not found in the 642 * dependencies. We maintain a simple common symbol table in 643 * the file object. 644 */ 645 struct common_symbol *cp; 646 647 STAILQ_FOREACH(cp, &file->common, link) { 648 if (strcmp(cp->name, name) == 0) { 649 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 650 " old common value=%p\n", cp->address)); 651 return (cp->address); 652 } 653 } 654 /* 655 * Round the symbol size up to align. 656 */ 657 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 658 cp = malloc(sizeof(struct common_symbol) 659 + common_size + strlen(name) + 1, M_LINKER, 660 M_WAITOK | M_ZERO); 661 if (cp == NULL) { 662 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 663 return (0); 664 } 665 cp->address = (caddr_t)(cp + 1); 666 cp->name = cp->address + common_size; 667 strcpy(cp->name, name); 668 bzero(cp->address, common_size); 669 STAILQ_INSERT_TAIL(&file->common, cp, link); 670 671 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 672 " value=%p\n", cp->address)); 673 return (cp->address); 674 } 675 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 676 return (0); 677} 678 679#ifdef DDB 680/* 681 * DDB Helpers. DDB has to look across multiple files with their own symbol 682 * tables and string tables. 683 * 684 * Note that we do not obey list locking protocols here. We really don't need 685 * DDB to hang because somebody's got the lock held. We'll take the chance 686 * that the files list is inconsistant instead. 687 */ 688 689int 690linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 691{ 692 linker_file_t lf; 693 694 TAILQ_FOREACH(lf, &linker_files, link) { 695 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 696 return (0); 697 } 698 return (ENOENT); 699} 700 701int 702linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 703{ 704 linker_file_t lf; 705 c_linker_sym_t best, es; 706 u_long diff, bestdiff, off; 707 708 best = 0; 709 off = (uintptr_t)value; 710 bestdiff = off; 711 TAILQ_FOREACH(lf, &linker_files, link) { 712 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 713 continue; 714 if (es != 0 && diff < bestdiff) { 715 best = es; 716 bestdiff = diff; 717 } 718 if (bestdiff == 0) 719 break; 720 } 721 if (best) { 722 *sym = best; 723 *diffp = bestdiff; 724 return (0); 725 } else { 726 *sym = 0; 727 *diffp = off; 728 return (ENOENT); 729 } 730} 731 732int 733linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 734{ 735 linker_file_t lf; 736 737 TAILQ_FOREACH(lf, &linker_files, link) { 738 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 739 return (0); 740 } 741 return (ENOENT); 742} 743#endif 744 745/* 746 * Syscalls. 747 */ 748/* 749 * MPSAFE 750 */ 751int 752kldload(struct thread *td, struct kldload_args *uap) 753{ 754 char *kldname, *modname; 755 char *pathname = NULL; 756 linker_file_t lf; 757 int error = 0; 758 759 td->td_retval[0] = -1; 760 761 mtx_lock(&Giant); 762 763 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 764 goto out; 765 766 if ((error = suser(td)) != 0) 767 goto out; 768 769 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 770 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 771 goto out; 772 773 /* 774 * If path do not contain qualified name or any dot in it 775 * (kldname.ko, or kldname.ver.ko) treat it as interface 776 * name. 777 */ 778 if (index(pathname, '/') || index(pathname, '.')) { 779 kldname = pathname; 780 modname = NULL; 781 } else { 782 kldname = NULL; 783 modname = pathname; 784 } 785 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 786 if (error) 787 goto out; 788 789 lf->userrefs++; 790 td->td_retval[0] = lf->id; 791out: 792 if (pathname) 793 free(pathname, M_TEMP); 794 mtx_unlock(&Giant); 795 return (error); 796} 797 798/* 799 * MPSAFE 800 */ 801static int 802kern_kldunload(struct thread *td, int fileid, int flags) 803{ 804 linker_file_t lf; 805 int error = 0; 806 807 mtx_lock(&Giant); 808 809 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 810 goto out; 811 812 if ((error = suser(td)) != 0) 813 goto out; 814 815 lf = linker_find_file_by_id(fileid); 816 if (lf) { 817 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 818 if (lf->userrefs == 0) { 819 /* 820 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 821 */ 822 printf("kldunload: attempt to unload file that was" 823 " loaded by the kernel\n"); 824 error = EBUSY; 825 goto out; 826 } 827 lf->userrefs--; 828 error = linker_file_unload(lf, flags); 829 if (error) 830 lf->userrefs++; 831 } else 832 error = ENOENT; 833out: 834 mtx_unlock(&Giant); 835 return (error); 836} 837 838/* 839 * MPSAFE 840 */ 841int 842kldunload(struct thread *td, struct kldunload_args *uap) 843{ 844 845 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 846} 847 848/* 849 * MPSAFE 850 */ 851int 852kldunloadf(struct thread *td, struct kldunloadf_args *uap) 853{ 854 855 if (uap->flags != LINKER_UNLOAD_NORMAL && 856 uap->flags != LINKER_UNLOAD_FORCE) 857 return (EINVAL); 858 return (kern_kldunload(td, uap->fileid, uap->flags)); 859} 860 861/* 862 * MPSAFE 863 */ 864int 865kldfind(struct thread *td, struct kldfind_args *uap) 866{ 867 char *pathname; 868 const char *filename; 869 linker_file_t lf; 870 int error = 0; 871 872#ifdef MAC 873 error = mac_check_kld_stat(td->td_ucred); 874 if (error) 875 return (error); 876#endif 877 878 mtx_lock(&Giant); 879 td->td_retval[0] = -1; 880 881 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 882 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 883 goto out; 884 885 filename = linker_basename(pathname); 886 lf = linker_find_file_by_name(filename); 887 if (lf) 888 td->td_retval[0] = lf->id; 889 else 890 error = ENOENT; 891out: 892 if (pathname) 893 free(pathname, M_TEMP); 894 mtx_unlock(&Giant); 895 return (error); 896} 897 898/* 899 * MPSAFE 900 */ 901int 902kldnext(struct thread *td, struct kldnext_args *uap) 903{ 904 linker_file_t lf; 905 int error = 0; 906 907#ifdef MAC 908 error = mac_check_kld_stat(td->td_ucred); 909 if (error) 910 return (error); 911#endif 912 913 mtx_lock(&Giant); 914 915 if (uap->fileid == 0) { 916 mtx_lock(&kld_mtx); 917 if (TAILQ_FIRST(&linker_files)) 918 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 919 else 920 td->td_retval[0] = 0; 921 mtx_unlock(&kld_mtx); 922 goto out; 923 } 924 lf = linker_find_file_by_id(uap->fileid); 925 if (lf) { 926 if (TAILQ_NEXT(lf, link)) 927 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 928 else 929 td->td_retval[0] = 0; 930 } else 931 error = ENOENT; 932out: 933 mtx_unlock(&Giant); 934 return (error); 935} 936 937/* 938 * MPSAFE 939 */ 940int 941kldstat(struct thread *td, struct kldstat_args *uap) 942{ 943 linker_file_t lf; 944 int error = 0; 945 int namelen, version; 946 struct kld_file_stat *stat; 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 lf = linker_find_file_by_id(uap->fileid); 957 if (lf == NULL) { 958 error = ENOENT; 959 goto out; 960 } 961 stat = uap->stat; 962 963 /* 964 * Check the version of the user's structure. 965 */ 966 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 967 goto out; 968 if (version != sizeof(struct kld_file_stat)) { 969 error = EINVAL; 970 goto out; 971 } 972 namelen = strlen(lf->filename) + 1; 973 if (namelen > MAXPATHLEN) 974 namelen = MAXPATHLEN; 975 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 976 goto out; 977 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 978 goto out; 979 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 980 goto out; 981 if ((error = copyout(&lf->address, &stat->address, 982 sizeof(caddr_t))) != 0) 983 goto out; 984 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 985 goto out; 986 987 td->td_retval[0] = 0; 988out: 989 mtx_unlock(&Giant); 990 return (error); 991} 992 993/* 994 * MPSAFE 995 */ 996int 997kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 998{ 999 linker_file_t lf; 1000 module_t mp; 1001 int error = 0; 1002 1003#ifdef MAC 1004 error = mac_check_kld_stat(td->td_ucred); 1005 if (error) 1006 return (error); 1007#endif 1008 1009 mtx_lock(&Giant); 1010 lf = linker_find_file_by_id(uap->fileid); 1011 if (lf) { 1012 MOD_SLOCK; 1013 mp = TAILQ_FIRST(&lf->modules); 1014 if (mp != NULL) 1015 td->td_retval[0] = module_getid(mp); 1016 else 1017 td->td_retval[0] = 0; 1018 MOD_SUNLOCK; 1019 } else 1020 error = ENOENT; 1021 mtx_unlock(&Giant); 1022 return (error); 1023} 1024 1025/* 1026 * MPSAFE 1027 */ 1028int 1029kldsym(struct thread *td, struct kldsym_args *uap) 1030{ 1031 char *symstr = NULL; 1032 c_linker_sym_t sym; 1033 linker_symval_t symval; 1034 linker_file_t lf; 1035 struct kld_sym_lookup lookup; 1036 int error = 0; 1037 1038#ifdef MAC 1039 error = mac_check_kld_stat(td->td_ucred); 1040 if (error) 1041 return (error); 1042#endif 1043 1044 mtx_lock(&Giant); 1045 1046 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1047 goto out; 1048 if (lookup.version != sizeof(lookup) || 1049 uap->cmd != KLDSYM_LOOKUP) { 1050 error = EINVAL; 1051 goto out; 1052 } 1053 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1054 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1055 goto out; 1056 if (uap->fileid != 0) { 1057 lf = linker_find_file_by_id(uap->fileid); 1058 if (lf == NULL) { 1059 error = ENOENT; 1060 goto out; 1061 } 1062 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1063 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1064 lookup.symvalue = (uintptr_t) symval.value; 1065 lookup.symsize = symval.size; 1066 error = copyout(&lookup, uap->data, sizeof(lookup)); 1067 } else 1068 error = ENOENT; 1069 } else { 1070 mtx_lock(&kld_mtx); 1071 TAILQ_FOREACH(lf, &linker_files, link) { 1072 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1073 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1074 lookup.symvalue = (uintptr_t)symval.value; 1075 lookup.symsize = symval.size; 1076 error = copyout(&lookup, uap->data, 1077 sizeof(lookup)); 1078 break; 1079 } 1080 } 1081 mtx_unlock(&kld_mtx); 1082 if (lf == NULL) 1083 error = ENOENT; 1084 } 1085out: 1086 if (symstr) 1087 free(symstr, M_TEMP); 1088 mtx_unlock(&Giant); 1089 return (error); 1090} 1091 1092/* 1093 * Preloaded module support 1094 */ 1095 1096static modlist_t 1097modlist_lookup(const char *name, int ver) 1098{ 1099 modlist_t mod; 1100 1101 TAILQ_FOREACH(mod, &found_modules, link) { 1102 if (strcmp(mod->name, name) == 0 && 1103 (ver == 0 || mod->version == ver)) 1104 return (mod); 1105 } 1106 return (NULL); 1107} 1108 1109static modlist_t 1110modlist_lookup2(const char *name, struct mod_depend *verinfo) 1111{ 1112 modlist_t mod, bestmod; 1113 int ver; 1114 1115 if (verinfo == NULL) 1116 return (modlist_lookup(name, 0)); 1117 bestmod = NULL; 1118 for (mod = TAILQ_FIRST(&found_modules); mod; 1119 mod = TAILQ_NEXT(mod, link)) { 1120 if (strcmp(mod->name, name) != 0) 1121 continue; 1122 ver = mod->version; 1123 if (ver == verinfo->md_ver_preferred) 1124 return (mod); 1125 if (ver >= verinfo->md_ver_minimum && 1126 ver <= verinfo->md_ver_maximum && 1127 (bestmod == NULL || ver > bestmod->version)) 1128 bestmod = mod; 1129 } 1130 return (bestmod); 1131} 1132 1133static modlist_t 1134modlist_newmodule(const char *modname, int version, linker_file_t container) 1135{ 1136 modlist_t mod; 1137 1138 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1139 if (mod == NULL) 1140 panic("no memory for module list"); 1141 mod->container = container; 1142 mod->name = modname; 1143 mod->version = version; 1144 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1145 return (mod); 1146} 1147 1148static void 1149linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1150 struct mod_metadata **stop, int preload) 1151{ 1152 struct mod_metadata *mp, **mdp; 1153 const char *modname; 1154 int ver; 1155 1156 for (mdp = start; mdp < stop; mdp++) { 1157 mp = *mdp; 1158 if (mp->md_type != MDT_VERSION) 1159 continue; 1160 modname = mp->md_cval; 1161 ver = ((struct mod_version *)mp->md_data)->mv_version; 1162 if (modlist_lookup(modname, ver) != NULL) { 1163 printf("module %s already present!\n", modname); 1164 /* XXX what can we do? this is a build error. :-( */ 1165 continue; 1166 } 1167 modlist_newmodule(modname, ver, lf); 1168 } 1169} 1170 1171static void 1172linker_preload(void *arg) 1173{ 1174 caddr_t modptr; 1175 const char *modname, *nmodname; 1176 char *modtype; 1177 linker_file_t lf; 1178 linker_class_t lc; 1179 int error; 1180 linker_file_list_t loaded_files; 1181 linker_file_list_t depended_files; 1182 struct mod_metadata *mp, *nmp; 1183 struct mod_metadata **start, **stop, **mdp, **nmdp; 1184 struct mod_depend *verinfo; 1185 int nver; 1186 int resolves; 1187 modlist_t mod; 1188 struct sysinit **si_start, **si_stop; 1189 1190 TAILQ_INIT(&loaded_files); 1191 TAILQ_INIT(&depended_files); 1192 TAILQ_INIT(&found_modules); 1193 error = 0; 1194 1195 modptr = NULL; 1196 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1197 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1198 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1199 if (modname == NULL) { 1200 printf("Preloaded module at %p does not have a" 1201 " name!\n", modptr); 1202 continue; 1203 } 1204 if (modtype == NULL) { 1205 printf("Preloaded module at %p does not have a type!\n", 1206 modptr); 1207 continue; 1208 } 1209 if (bootverbose) 1210 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1211 modptr); 1212 lf = NULL; 1213 TAILQ_FOREACH(lc, &classes, link) { 1214 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1215 if (!error) 1216 break; 1217 lf = NULL; 1218 } 1219 if (lf) 1220 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1221 } 1222 1223 /* 1224 * First get a list of stuff in the kernel. 1225 */ 1226 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1227 &stop, NULL) == 0) 1228 linker_addmodules(linker_kernel_file, start, stop, 1); 1229 1230 /* 1231 * this is a once-off kinky bubble sort resolve relocation dependency 1232 * requirements 1233 */ 1234restart: 1235 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1236 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1237 &stop, NULL); 1238 /* 1239 * First, look to see if we would successfully link with this 1240 * stuff. 1241 */ 1242 resolves = 1; /* unless we know otherwise */ 1243 if (!error) { 1244 for (mdp = start; mdp < stop; mdp++) { 1245 mp = *mdp; 1246 if (mp->md_type != MDT_DEPEND) 1247 continue; 1248 modname = mp->md_cval; 1249 verinfo = mp->md_data; 1250 for (nmdp = start; nmdp < stop; nmdp++) { 1251 nmp = *nmdp; 1252 if (nmp->md_type != MDT_VERSION) 1253 continue; 1254 nmodname = nmp->md_cval; 1255 if (strcmp(modname, nmodname) == 0) 1256 break; 1257 } 1258 if (nmdp < stop) /* it's a self reference */ 1259 continue; 1260 1261 /* 1262 * ok, the module isn't here yet, we 1263 * are not finished 1264 */ 1265 if (modlist_lookup2(modname, verinfo) == NULL) 1266 resolves = 0; 1267 } 1268 } 1269 /* 1270 * OK, if we found our modules, we can link. So, "provide" 1271 * the modules inside and add it to the end of the link order 1272 * list. 1273 */ 1274 if (resolves) { 1275 if (!error) { 1276 for (mdp = start; mdp < stop; mdp++) { 1277 mp = *mdp; 1278 if (mp->md_type != MDT_VERSION) 1279 continue; 1280 modname = mp->md_cval; 1281 nver = ((struct mod_version *) 1282 mp->md_data)->mv_version; 1283 if (modlist_lookup(modname, 1284 nver) != NULL) { 1285 printf("module %s already" 1286 " present!\n", modname); 1287 linker_file_unload(lf, 1288 LINKER_UNLOAD_FORCE); 1289 TAILQ_REMOVE(&loaded_files, 1290 lf, loaded); 1291 /* we changed tailq next ptr */ 1292 goto restart; 1293 } 1294 modlist_newmodule(modname, nver, lf); 1295 } 1296 } 1297 TAILQ_REMOVE(&loaded_files, lf, loaded); 1298 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1299 /* 1300 * Since we provided modules, we need to restart the 1301 * sort so that the previous files that depend on us 1302 * have a chance. Also, we've busted the tailq next 1303 * pointer with the REMOVE. 1304 */ 1305 goto restart; 1306 } 1307 } 1308 1309 /* 1310 * At this point, we check to see what could not be resolved.. 1311 */ 1312 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1313 printf("KLD file %s is missing dependencies\n", lf->filename); 1314 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1315 TAILQ_REMOVE(&loaded_files, lf, loaded); 1316 } 1317 1318 /* 1319 * We made it. Finish off the linking in the order we determined. 1320 */ 1321 TAILQ_FOREACH(lf, &depended_files, loaded) { 1322 if (linker_kernel_file) { 1323 linker_kernel_file->refs++; 1324 error = linker_file_add_dependency(lf, 1325 linker_kernel_file); 1326 if (error) 1327 panic("cannot add dependency"); 1328 } 1329 lf->userrefs++; /* so we can (try to) kldunload it */ 1330 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1331 &stop, NULL); 1332 if (!error) { 1333 for (mdp = start; mdp < stop; mdp++) { 1334 mp = *mdp; 1335 if (mp->md_type != MDT_DEPEND) 1336 continue; 1337 modname = mp->md_cval; 1338 verinfo = mp->md_data; 1339 mod = modlist_lookup2(modname, verinfo); 1340 mod->container->refs++; 1341 error = linker_file_add_dependency(lf, 1342 mod->container); 1343 if (error) 1344 panic("cannot add dependency"); 1345 } 1346 } 1347 /* 1348 * Now do relocation etc using the symbol search paths 1349 * established by the dependencies 1350 */ 1351 error = LINKER_LINK_PRELOAD_FINISH(lf); 1352 if (error) { 1353 printf("KLD file %s - could not finalize loading\n", 1354 lf->filename); 1355 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1356 continue; 1357 } 1358 linker_file_register_modules(lf); 1359 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1360 &si_stop, NULL) == 0) 1361 sysinit_add(si_start, si_stop); 1362 linker_file_register_sysctls(lf); 1363 lf->flags |= LINKER_FILE_LINKED; 1364 } 1365 /* woohoo! we made it! */ 1366} 1367 1368SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1369 1370/* 1371 * Search for a not-loaded module by name. 1372 * 1373 * Modules may be found in the following locations: 1374 * 1375 * - preloaded (result is just the module name) - on disk (result is full path 1376 * to module) 1377 * 1378 * If the module name is qualified in any way (contains path, etc.) the we 1379 * simply return a copy of it. 1380 * 1381 * The search path can be manipulated via sysctl. Note that we use the ';' 1382 * character as a separator to be consistent with the bootloader. 1383 */ 1384 1385static char linker_hintfile[] = "linker.hints"; 1386static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1387 1388SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1389 sizeof(linker_path), "module load search path"); 1390 1391TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1392 1393static char *linker_ext_list[] = { 1394 "", 1395 ".ko", 1396 NULL 1397}; 1398 1399/* 1400 * Check if file actually exists either with or without extension listed in 1401 * the linker_ext_list. (probably should be generic for the rest of the 1402 * kernel) 1403 */ 1404static char * 1405linker_lookup_file(const char *path, int pathlen, const char *name, 1406 int namelen, struct vattr *vap) 1407{ 1408 struct nameidata nd; 1409 struct thread *td = curthread; /* XXX */ 1410 char *result, **cpp, *sep; 1411 int error, len, extlen, reclen, flags; 1412 enum vtype type; 1413 1414 extlen = 0; 1415 for (cpp = linker_ext_list; *cpp; cpp++) { 1416 len = strlen(*cpp); 1417 if (len > extlen) 1418 extlen = len; 1419 } 1420 extlen++; /* trailing '\0' */ 1421 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1422 1423 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1424 result = malloc(reclen, M_LINKER, M_WAITOK); 1425 for (cpp = linker_ext_list; *cpp; cpp++) { 1426 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1427 namelen, name, *cpp); 1428 /* 1429 * Attempt to open the file, and return the path if 1430 * we succeed and it's a regular file. 1431 */ 1432 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1433 flags = FREAD; 1434 error = vn_open(&nd, &flags, 0, -1); 1435 if (error == 0) { 1436 NDFREE(&nd, NDF_ONLY_PNBUF); 1437 type = nd.ni_vp->v_type; 1438 if (vap) 1439 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1440 VOP_UNLOCK(nd.ni_vp, 0, td); 1441 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1442 if (type == VREG) 1443 return (result); 1444 } 1445 } 1446 free(result, M_LINKER); 1447 return (NULL); 1448} 1449 1450#define INT_ALIGN(base, ptr) ptr = \ 1451 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1452 1453/* 1454 * Lookup KLD which contains requested module in the "linker.hints" file. If 1455 * version specification is available, then try to find the best KLD. 1456 * Otherwise just find the latest one. 1457 */ 1458static char * 1459linker_hints_lookup(const char *path, int pathlen, const char *modname, 1460 int modnamelen, struct mod_depend *verinfo) 1461{ 1462 struct thread *td = curthread; /* XXX */ 1463 struct ucred *cred = td ? td->td_ucred : NULL; 1464 struct nameidata nd; 1465 struct vattr vattr, mattr; 1466 u_char *hints = NULL; 1467 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1468 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1469 1470 result = NULL; 1471 bestver = found = 0; 1472 1473 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1474 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1475 strlen(sep) + 1; 1476 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1477 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1478 linker_hintfile); 1479 1480 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1481 flags = FREAD; 1482 error = vn_open(&nd, &flags, 0, -1); 1483 if (error) 1484 goto bad; 1485 NDFREE(&nd, NDF_ONLY_PNBUF); 1486 if (nd.ni_vp->v_type != VREG) 1487 goto bad; 1488 best = cp = NULL; 1489 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1490 if (error) 1491 goto bad; 1492 /* 1493 * XXX: we need to limit this number to some reasonable value 1494 */ 1495 if (vattr.va_size > 100 * 1024) { 1496 printf("hints file too large %ld\n", (long)vattr.va_size); 1497 goto bad; 1498 } 1499 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1500 if (hints == NULL) 1501 goto bad; 1502 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1503 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1504 if (error) 1505 goto bad; 1506 VOP_UNLOCK(nd.ni_vp, 0, td); 1507 vn_close(nd.ni_vp, FREAD, cred, td); 1508 nd.ni_vp = NULL; 1509 if (reclen != 0) { 1510 printf("can't read %d\n", reclen); 1511 goto bad; 1512 } 1513 intp = (int *)hints; 1514 ival = *intp++; 1515 if (ival != LINKER_HINTS_VERSION) { 1516 printf("hints file version mismatch %d\n", ival); 1517 goto bad; 1518 } 1519 bufend = hints + vattr.va_size; 1520 recptr = (u_char *)intp; 1521 clen = blen = 0; 1522 while (recptr < bufend && !found) { 1523 intp = (int *)recptr; 1524 reclen = *intp++; 1525 ival = *intp++; 1526 cp = (char *)intp; 1527 switch (ival) { 1528 case MDT_VERSION: 1529 clen = *cp++; 1530 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1531 break; 1532 cp += clen; 1533 INT_ALIGN(hints, cp); 1534 ival = *(int *)cp; 1535 cp += sizeof(int); 1536 clen = *cp++; 1537 if (verinfo == NULL || 1538 ival == verinfo->md_ver_preferred) { 1539 found = 1; 1540 break; 1541 } 1542 if (ival >= verinfo->md_ver_minimum && 1543 ival <= verinfo->md_ver_maximum && 1544 ival > bestver) { 1545 bestver = ival; 1546 best = cp; 1547 blen = clen; 1548 } 1549 break; 1550 default: 1551 break; 1552 } 1553 recptr += reclen + sizeof(int); 1554 } 1555 /* 1556 * Finally check if KLD is in the place 1557 */ 1558 if (found) 1559 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1560 else if (best) 1561 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1562 1563 /* 1564 * KLD is newer than hints file. What we should do now? 1565 */ 1566 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1567 printf("warning: KLD '%s' is newer than the linker.hints" 1568 " file\n", result); 1569bad: 1570 free(pathbuf, M_LINKER); 1571 if (hints) 1572 free(hints, M_TEMP); 1573 if (nd.ni_vp != NULL) { 1574 VOP_UNLOCK(nd.ni_vp, 0, td); 1575 vn_close(nd.ni_vp, FREAD, cred, td); 1576 } 1577 /* 1578 * If nothing found or hints is absent - fallback to the old 1579 * way by using "kldname[.ko]" as module name. 1580 */ 1581 if (!found && !bestver && result == NULL) 1582 result = linker_lookup_file(path, pathlen, modname, 1583 modnamelen, NULL); 1584 return (result); 1585} 1586 1587/* 1588 * Lookup KLD which contains requested module in the all directories. 1589 */ 1590static char * 1591linker_search_module(const char *modname, int modnamelen, 1592 struct mod_depend *verinfo) 1593{ 1594 char *cp, *ep, *result; 1595 1596 /* 1597 * traverse the linker path 1598 */ 1599 for (cp = linker_path; *cp; cp = ep + 1) { 1600 /* find the end of this component */ 1601 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1602 result = linker_hints_lookup(cp, ep - cp, modname, 1603 modnamelen, verinfo); 1604 if (result != NULL) 1605 return (result); 1606 if (*ep == 0) 1607 break; 1608 } 1609 return (NULL); 1610} 1611 1612/* 1613 * Search for module in all directories listed in the linker_path. 1614 */ 1615static char * 1616linker_search_kld(const char *name) 1617{ 1618 char *cp, *ep, *result, **cpp; 1619 int extlen, len; 1620 1621 /* qualified at all? */ 1622 if (index(name, '/')) 1623 return (linker_strdup(name)); 1624 1625 extlen = 0; 1626 for (cpp = linker_ext_list; *cpp; cpp++) { 1627 len = strlen(*cpp); 1628 if (len > extlen) 1629 extlen = len; 1630 } 1631 extlen++; /* trailing '\0' */ 1632 1633 /* traverse the linker path */ 1634 len = strlen(name); 1635 for (ep = linker_path; *ep; ep++) { 1636 cp = ep; 1637 /* find the end of this component */ 1638 for (; *ep != 0 && *ep != ';'; ep++); 1639 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1640 if (result != NULL) 1641 return (result); 1642 } 1643 return (NULL); 1644} 1645 1646static const char * 1647linker_basename(const char *path) 1648{ 1649 const char *filename; 1650 1651 filename = rindex(path, '/'); 1652 if (filename == NULL) 1653 return path; 1654 if (filename[1]) 1655 filename++; 1656 return (filename); 1657} 1658 1659/* 1660 * Find a file which contains given module and load it, if "parent" is not 1661 * NULL, register a reference to it. 1662 */ 1663int 1664linker_load_module(const char *kldname, const char *modname, 1665 struct linker_file *parent, struct mod_depend *verinfo, 1666 struct linker_file **lfpp) 1667{ 1668 linker_file_t lfdep; 1669 const char *filename; 1670 char *pathname; 1671 int error; 1672 1673 if (modname == NULL) { 1674 /* 1675 * We have to load KLD 1676 */ 1677 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1678 " is not NULL")); 1679 pathname = linker_search_kld(kldname); 1680 } else { 1681 if (modlist_lookup2(modname, verinfo) != NULL) 1682 return (EEXIST); 1683 if (kldname != NULL) 1684 pathname = linker_strdup(kldname); 1685 else if (rootvnode == NULL) 1686 pathname = NULL; 1687 else 1688 /* 1689 * Need to find a KLD with required module 1690 */ 1691 pathname = linker_search_module(modname, 1692 strlen(modname), verinfo); 1693 } 1694 if (pathname == NULL) 1695 return (ENOENT); 1696 1697 /* 1698 * Can't load more than one file with the same basename XXX: 1699 * Actually it should be possible to have multiple KLDs with 1700 * the same basename but different path because they can 1701 * provide different versions of the same modules. 1702 */ 1703 filename = linker_basename(pathname); 1704 if (linker_find_file_by_name(filename)) { 1705 error = EEXIST; 1706 goto out; 1707 } 1708 do { 1709 error = linker_load_file(pathname, &lfdep); 1710 if (error) 1711 break; 1712 if (modname && verinfo && 1713 modlist_lookup2(modname, verinfo) == NULL) { 1714 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1715 error = ENOENT; 1716 break; 1717 } 1718 if (parent) { 1719 error = linker_file_add_dependency(parent, lfdep); 1720 if (error) 1721 break; 1722 } 1723 if (lfpp) 1724 *lfpp = lfdep; 1725 } while (0); 1726out: 1727 if (pathname) 1728 free(pathname, M_LINKER); 1729 return (error); 1730} 1731 1732/* 1733 * This routine is responsible for finding dependencies of userland initiated 1734 * kldload(2)'s of files. 1735 */ 1736int 1737linker_load_dependencies(linker_file_t lf) 1738{ 1739 linker_file_t lfdep; 1740 struct mod_metadata **start, **stop, **mdp, **nmdp; 1741 struct mod_metadata *mp, *nmp; 1742 struct mod_depend *verinfo; 1743 modlist_t mod; 1744 const char *modname, *nmodname; 1745 int ver, error = 0, count; 1746 1747 /* 1748 * All files are dependant on /kernel. 1749 */ 1750 if (linker_kernel_file) { 1751 linker_kernel_file->refs++; 1752 error = linker_file_add_dependency(lf, linker_kernel_file); 1753 if (error) 1754 return (error); 1755 } 1756 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1757 &count) != 0) 1758 return (0); 1759 for (mdp = start; mdp < stop; mdp++) { 1760 mp = *mdp; 1761 if (mp->md_type != MDT_VERSION) 1762 continue; 1763 modname = mp->md_cval; 1764 ver = ((struct mod_version *)mp->md_data)->mv_version; 1765 mod = modlist_lookup(modname, ver); 1766 if (mod != NULL) { 1767 printf("interface %s.%d already present in the KLD" 1768 " '%s'!\n", modname, ver, 1769 mod->container->filename); 1770 return (EEXIST); 1771 } 1772 } 1773 1774 for (mdp = start; mdp < stop; mdp++) { 1775 mp = *mdp; 1776 if (mp->md_type != MDT_DEPEND) 1777 continue; 1778 modname = mp->md_cval; 1779 verinfo = mp->md_data; 1780 nmodname = NULL; 1781 for (nmdp = start; nmdp < stop; nmdp++) { 1782 nmp = *nmdp; 1783 if (nmp->md_type != MDT_VERSION) 1784 continue; 1785 nmodname = nmp->md_cval; 1786 if (strcmp(modname, nmodname) == 0) 1787 break; 1788 } 1789 if (nmdp < stop)/* early exit, it's a self reference */ 1790 continue; 1791 mod = modlist_lookup2(modname, verinfo); 1792 if (mod) { /* woohoo, it's loaded already */ 1793 lfdep = mod->container; 1794 lfdep->refs++; 1795 error = linker_file_add_dependency(lf, lfdep); 1796 if (error) 1797 break; 1798 continue; 1799 } 1800 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1801 if (error) { 1802 printf("KLD %s: depends on %s - not available\n", 1803 lf->filename, modname); 1804 break; 1805 } 1806 } 1807 1808 if (error) 1809 return (error); 1810 linker_addmodules(lf, start, stop, 0); 1811 return (error); 1812} 1813 1814static int 1815sysctl_kern_function_list_iterate(const char *name, void *opaque) 1816{ 1817 struct sysctl_req *req; 1818 1819 req = opaque; 1820 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1821} 1822 1823/* 1824 * Export a nul-separated, double-nul-terminated list of all function names 1825 * in the kernel. 1826 */ 1827static int 1828sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1829{ 1830 linker_file_t lf; 1831 int error; 1832 1833#ifdef MAC 1834 error = mac_check_kld_stat(req->td->td_ucred); 1835 if (error) 1836 return (error); 1837#endif 1838 error = sysctl_wire_old_buffer(req, 0); 1839 if (error != 0) 1840 return (error); 1841 mtx_lock(&kld_mtx); 1842 TAILQ_FOREACH(lf, &linker_files, link) { 1843 error = LINKER_EACH_FUNCTION_NAME(lf, 1844 sysctl_kern_function_list_iterate, req); 1845 if (error) { 1846 mtx_unlock(&kld_mtx); 1847 return (error); 1848 } 1849 } 1850 mtx_unlock(&kld_mtx); 1851 return (SYSCTL_OUT(req, "", 1)); 1852} 1853 1854SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1855 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 1856