kern_linker.c revision 159800
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 159800 2006-06-20 20:41:15Z 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/* 71 * Find a currently loaded file given its filename. 72 */ 73static linker_file_t linker_find_file_by_name(const char* _filename); 74 75/* 76 * Find a currently loaded file given its file id. 77 */ 78static linker_file_t linker_find_file_by_id(int _fileid); 79 80/* Metadata from the static kernel */ 81SET_DECLARE(modmetadata_set, struct mod_metadata); 82 83MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 84 85linker_file_t linker_kernel_file; 86 87static struct mtx kld_mtx; /* kernel linker mutex */ 88 89static linker_class_list_t classes; 90static linker_file_list_t linker_files; 91static int next_file_id = 1; 92static int linker_no_more_classes = 0; 93 94#define LINKER_GET_NEXT_FILE_ID(a) do { \ 95 linker_file_t lftmp; \ 96 \ 97retry: \ 98 mtx_lock(&kld_mtx); \ 99 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 100 if (next_file_id == lftmp->id) { \ 101 next_file_id++; \ 102 mtx_unlock(&kld_mtx); \ 103 goto retry; \ 104 } \ 105 } \ 106 (a) = next_file_id; \ 107 mtx_unlock(&kld_mtx); /* Hold for safe read of id variable */ \ 108} while(0) 109 110 111/* XXX wrong name; we're looking at version provision tags here, not modules */ 112typedef TAILQ_HEAD(, modlist) modlisthead_t; 113struct modlist { 114 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 115 linker_file_t container; 116 const char *name; 117 int version; 118}; 119typedef struct modlist *modlist_t; 120static modlisthead_t found_modules; 121 122static int linker_file_add_dependency(linker_file_t file, 123 linker_file_t dep); 124static int linker_load_module(const char *kldname, 125 const char *modname, struct linker_file *parent, 126 struct mod_depend *verinfo, struct linker_file **lfpp); 127static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo); 128 129static char * 130linker_strdup(const char *str) 131{ 132 char *result; 133 134 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 135 strcpy(result, str); 136 return (result); 137} 138 139static void 140linker_init(void *arg) 141{ 142 143 mtx_init(&kld_mtx, "kernel linker", NULL, MTX_DEF); 144 TAILQ_INIT(&classes); 145 TAILQ_INIT(&linker_files); 146} 147 148SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 149 150static void 151linker_stop_class_add(void *arg) 152{ 153 154 linker_no_more_classes = 1; 155} 156 157SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 158 159int 160linker_add_class(linker_class_t lc) 161{ 162 163 /* 164 * We disallow any class registration past SI_ORDER_ANY 165 * of SI_SUB_KLD. We bump the reference count to keep the 166 * ops from being freed. 167 */ 168 if (linker_no_more_classes == 1) 169 return (EPERM); 170 kobj_class_compile((kobj_class_t) lc); 171 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 172 TAILQ_INSERT_TAIL(&classes, lc, link); 173 return (0); 174} 175 176static void 177linker_file_sysinit(linker_file_t lf) 178{ 179 struct sysinit **start, **stop, **sipp, **xipp, *save; 180 181 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 182 lf->filename)); 183 184 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 185 return; 186 /* 187 * Perform a bubble sort of the system initialization objects by 188 * their subsystem (primary key) and order (secondary key). 189 * 190 * Since some things care about execution order, this is the operation 191 * which ensures continued function. 192 */ 193 for (sipp = start; sipp < stop; sipp++) { 194 for (xipp = sipp + 1; xipp < stop; xipp++) { 195 if ((*sipp)->subsystem < (*xipp)->subsystem || 196 ((*sipp)->subsystem == (*xipp)->subsystem && 197 (*sipp)->order <= (*xipp)->order)) 198 continue; /* skip */ 199 save = *sipp; 200 *sipp = *xipp; 201 *xipp = save; 202 } 203 } 204 205 /* 206 * Traverse the (now) ordered list of system initialization tasks. 207 * Perform each task, and continue on to the next task. 208 */ 209 for (sipp = start; sipp < stop; sipp++) { 210 if ((*sipp)->subsystem == SI_SUB_DUMMY) 211 continue; /* skip dummy task(s) */ 212 213 /* Call function */ 214 (*((*sipp)->func)) ((*sipp)->udata); 215 } 216} 217 218static void 219linker_file_sysuninit(linker_file_t lf) 220{ 221 struct sysinit **start, **stop, **sipp, **xipp, *save; 222 223 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 224 lf->filename)); 225 226 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 227 NULL) != 0) 228 return; 229 230 /* 231 * Perform a reverse bubble sort of the system initialization objects 232 * by their subsystem (primary key) and order (secondary key). 233 * 234 * Since some things care about execution order, this is the operation 235 * which ensures continued function. 236 */ 237 for (sipp = start; sipp < stop; sipp++) { 238 for (xipp = sipp + 1; xipp < stop; xipp++) { 239 if ((*sipp)->subsystem > (*xipp)->subsystem || 240 ((*sipp)->subsystem == (*xipp)->subsystem && 241 (*sipp)->order >= (*xipp)->order)) 242 continue; /* skip */ 243 save = *sipp; 244 *sipp = *xipp; 245 *xipp = save; 246 } 247 } 248 249 /* 250 * Traverse the (now) ordered list of system initialization tasks. 251 * Perform each task, and continue on to the next task. 252 */ 253 for (sipp = start; sipp < stop; sipp++) { 254 if ((*sipp)->subsystem == SI_SUB_DUMMY) 255 continue; /* skip dummy task(s) */ 256 257 /* Call function */ 258 (*((*sipp)->func)) ((*sipp)->udata); 259 } 260} 261 262static void 263linker_file_register_sysctls(linker_file_t lf) 264{ 265 struct sysctl_oid **start, **stop, **oidp; 266 267 KLD_DPF(FILE, 268 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 269 lf->filename)); 270 271 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 272 return; 273 274 for (oidp = start; oidp < stop; oidp++) 275 sysctl_register_oid(*oidp); 276} 277 278static void 279linker_file_unregister_sysctls(linker_file_t lf) 280{ 281 struct sysctl_oid **start, **stop, **oidp; 282 283 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 284 " for %s\n", lf->filename)); 285 286 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 287 return; 288 289 for (oidp = start; oidp < stop; oidp++) 290 sysctl_unregister_oid(*oidp); 291} 292 293static int 294linker_file_register_modules(linker_file_t lf) 295{ 296 struct mod_metadata **start, **stop, **mdp; 297 const moduledata_t *moddata; 298 int first_error, error; 299 300 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 301 " in %s\n", lf->filename)); 302 303 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 304 &stop, 0) != 0) { 305 /* 306 * This fallback should be unnecessary, but if we get booted 307 * from boot2 instead of loader and we are missing our 308 * metadata then we have to try the best we can. 309 */ 310 if (lf == linker_kernel_file) { 311 start = SET_BEGIN(modmetadata_set); 312 stop = SET_LIMIT(modmetadata_set); 313 } else 314 return (0); 315 } 316 first_error = 0; 317 for (mdp = start; mdp < stop; mdp++) { 318 if ((*mdp)->md_type != MDT_MODULE) 319 continue; 320 moddata = (*mdp)->md_data; 321 KLD_DPF(FILE, ("Registering module %s in %s\n", 322 moddata->name, lf->filename)); 323 error = module_register(moddata, lf); 324 if (error) { 325 printf("Module %s failed to register: %d\n", 326 moddata->name, error); 327 if (first_error == 0) 328 first_error = error; 329 } 330 } 331 return (first_error); 332} 333 334static void 335linker_init_kernel_modules(void) 336{ 337 338 linker_file_register_modules(linker_kernel_file); 339} 340 341SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 342 343static int 344linker_load_file(const char *filename, linker_file_t *result) 345{ 346 linker_class_t lc; 347 linker_file_t lf; 348 int foundfile, error; 349 350 /* Refuse to load modules if securelevel raised */ 351 if (securelevel > 0) 352 return (EPERM); 353 354 lf = linker_find_file_by_name(filename); 355 if (lf) { 356 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 357 " incrementing refs\n", filename)); 358 *result = lf; 359 lf->refs++; 360 return (0); 361 } 362 foundfile = 0; 363 error = 0; 364 365 /* 366 * We do not need to protect (lock) classes here because there is 367 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 368 * and there is no class deregistration mechanism at this time. 369 */ 370 TAILQ_FOREACH(lc, &classes, link) { 371 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 372 filename)); 373 error = LINKER_LOAD_FILE(lc, filename, &lf); 374 /* 375 * If we got something other than ENOENT, then it exists but 376 * we cannot load it for some other reason. 377 */ 378 if (error != ENOENT) 379 foundfile = 1; 380 if (lf) { 381 error = linker_file_register_modules(lf); 382 if (error == EEXIST) { 383 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 384 return (error); 385 } 386 linker_file_register_sysctls(lf); 387 linker_file_sysinit(lf); 388 lf->flags |= LINKER_FILE_LINKED; 389 *result = lf; 390 return (0); 391 } 392 } 393 /* 394 * Less than ideal, but tells the user whether it failed to load or 395 * the module was not found. 396 */ 397 if (foundfile) { 398 /* 399 * Format not recognized or otherwise unloadable. 400 * When loading a module that is statically built into 401 * the kernel EEXIST percolates back up as the return 402 * value. Preserve this so that apps like sysinstall 403 * can recognize this special case and not post bogus 404 * dialog boxes. 405 */ 406 if (error != EEXIST) 407 error = ENOEXEC; 408 } else 409 error = ENOENT; /* Nothing found */ 410 return (error); 411} 412 413int 414linker_reference_module(const char *modname, struct mod_depend *verinfo, 415 linker_file_t *result) 416{ 417 modlist_t mod; 418 419 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 420 *result = mod->container; 421 (*result)->refs++; 422 return (0); 423 } 424 425 return (linker_load_module(NULL, modname, NULL, verinfo, result)); 426} 427 428static linker_file_t 429linker_find_file_by_name(const char *filename) 430{ 431 linker_file_t lf; 432 char *koname; 433 434 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 435 sprintf(koname, "%s.ko", filename); 436 437 mtx_lock(&kld_mtx); 438 TAILQ_FOREACH(lf, &linker_files, link) { 439 if (strcmp(lf->filename, koname) == 0) 440 break; 441 if (strcmp(lf->filename, filename) == 0) 442 break; 443 } 444 mtx_unlock(&kld_mtx); 445 free(koname, M_LINKER); 446 return (lf); 447} 448 449static linker_file_t 450linker_find_file_by_id(int fileid) 451{ 452 linker_file_t lf; 453 454 mtx_lock(&kld_mtx); 455 TAILQ_FOREACH(lf, &linker_files, link) 456 if (lf->id == fileid) 457 break; 458 mtx_unlock(&kld_mtx); 459 return (lf); 460} 461 462int 463linker_file_foreach(linker_predicate_t *predicate, void *context) 464{ 465 linker_file_t lf; 466 int retval = 0; 467 468 mtx_lock(&Giant); 469 TAILQ_FOREACH(lf, &linker_files, link) { 470 retval = predicate(lf, context); 471 if (retval != 0) 472 break; 473 } 474 mtx_unlock(&Giant); 475 return (retval); 476} 477 478linker_file_t 479linker_make_file(const char *pathname, linker_class_t lc) 480{ 481 linker_file_t lf; 482 const char *filename; 483 484 filename = linker_basename(pathname); 485 486 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 487 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 488 if (lf == NULL) 489 return (NULL); 490 lf->refs = 1; 491 lf->userrefs = 0; 492 lf->flags = 0; 493 lf->filename = linker_strdup(filename); 494 LINKER_GET_NEXT_FILE_ID(lf->id); 495 lf->ndeps = 0; 496 lf->deps = NULL; 497 STAILQ_INIT(&lf->common); 498 TAILQ_INIT(&lf->modules); 499 mtx_lock(&kld_mtx); 500 TAILQ_INSERT_TAIL(&linker_files, lf, link); 501 mtx_unlock(&kld_mtx); 502 return (lf); 503} 504 505int 506linker_file_unload(linker_file_t file, int flags) 507{ 508 module_t mod, next; 509 modlist_t ml, nextml; 510 struct common_symbol *cp; 511 int error, i; 512 513 /* Refuse to unload modules if securelevel raised. */ 514 if (securelevel > 0) 515 return (EPERM); 516#ifdef MAC 517 error = mac_check_kld_unload(curthread->td_ucred); 518 if (error) 519 return (error); 520#endif 521 522 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 523 524 /* Easy case of just dropping a reference. */ 525 if (file->refs > 1) { 526 file->refs--; 527 return (0); 528 } 529 530 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 531 " informing modules\n")); 532 533 /* 534 * Inform any modules associated with this file. 535 */ 536 MOD_XLOCK; 537 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 538 next = module_getfnext(mod); 539 MOD_XUNLOCK; 540 541 /* 542 * Give the module a chance to veto the unload. 543 */ 544 if ((error = module_unload(mod, flags)) != 0) { 545 KLD_DPF(FILE, ("linker_file_unload: module %p" 546 " vetoes unload\n", mod)); 547 return (error); 548 } 549 MOD_XLOCK; 550 module_release(mod); 551 } 552 MOD_XUNLOCK; 553 554 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 555 if (ml->container == file) { 556 TAILQ_REMOVE(&found_modules, ml, link); 557 free(ml, M_LINKER); 558 } 559 } 560 561 /* 562 * Don't try to run SYSUNINITs if we are unloaded due to a 563 * link error. 564 */ 565 if (file->flags & LINKER_FILE_LINKED) { 566 linker_file_sysuninit(file); 567 linker_file_unregister_sysctls(file); 568 } 569 mtx_lock(&kld_mtx); 570 TAILQ_REMOVE(&linker_files, file, link); 571 mtx_unlock(&kld_mtx); 572 573 if (file->deps) { 574 for (i = 0; i < file->ndeps; i++) 575 linker_file_unload(file->deps[i], flags); 576 free(file->deps, M_LINKER); 577 file->deps = NULL; 578 } 579 for (cp = STAILQ_FIRST(&file->common); cp; 580 cp = STAILQ_FIRST(&file->common)) { 581 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 582 free(cp, M_LINKER); 583 } 584 585 LINKER_UNLOAD(file); 586 if (file->filename) { 587 free(file->filename, M_LINKER); 588 file->filename = NULL; 589 } 590 kobj_delete((kobj_t) file, M_LINKER); 591 return (0); 592} 593 594static int 595linker_file_add_dependency(linker_file_t file, linker_file_t dep) 596{ 597 linker_file_t *newdeps; 598 599 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 600 M_LINKER, M_WAITOK | M_ZERO); 601 if (newdeps == NULL) 602 return (ENOMEM); 603 604 if (file->deps) { 605 bcopy(file->deps, newdeps, 606 file->ndeps * sizeof(linker_file_t *)); 607 free(file->deps, M_LINKER); 608 } 609 file->deps = newdeps; 610 file->deps[file->ndeps] = dep; 611 file->ndeps++; 612 return (0); 613} 614 615/* 616 * Locate a linker set and its contents. This is a helper function to avoid 617 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 618 */ 619int 620linker_file_lookup_set(linker_file_t file, const char *name, 621 void *firstp, void *lastp, int *countp) 622{ 623 624 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 625} 626 627caddr_t 628linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 629{ 630 c_linker_sym_t sym; 631 linker_symval_t symval; 632 caddr_t address; 633 size_t common_size = 0; 634 int i; 635 636 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 637 file, name, deps)); 638 639 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 640 LINKER_SYMBOL_VALUES(file, sym, &symval); 641 if (symval.value == 0) 642 /* 643 * For commons, first look them up in the 644 * dependencies and only allocate space if not found 645 * there. 646 */ 647 common_size = symval.size; 648 else { 649 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 650 ".value=%p\n", symval.value)); 651 return (symval.value); 652 } 653 } 654 if (deps) { 655 for (i = 0; i < file->ndeps; i++) { 656 address = linker_file_lookup_symbol(file->deps[i], 657 name, 0); 658 if (address) { 659 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 660 " deps value=%p\n", address)); 661 return (address); 662 } 663 } 664 } 665 if (common_size > 0) { 666 /* 667 * This is a common symbol which was not found in the 668 * dependencies. We maintain a simple common symbol table in 669 * the file object. 670 */ 671 struct common_symbol *cp; 672 673 STAILQ_FOREACH(cp, &file->common, link) { 674 if (strcmp(cp->name, name) == 0) { 675 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 676 " old common value=%p\n", cp->address)); 677 return (cp->address); 678 } 679 } 680 /* 681 * Round the symbol size up to align. 682 */ 683 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 684 cp = malloc(sizeof(struct common_symbol) 685 + common_size + strlen(name) + 1, M_LINKER, 686 M_WAITOK | M_ZERO); 687 cp->address = (caddr_t)(cp + 1); 688 cp->name = cp->address + common_size; 689 strcpy(cp->name, name); 690 bzero(cp->address, common_size); 691 STAILQ_INSERT_TAIL(&file->common, cp, link); 692 693 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 694 " value=%p\n", cp->address)); 695 return (cp->address); 696 } 697 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 698 return (0); 699} 700 701#ifdef DDB 702/* 703 * DDB Helpers. DDB has to look across multiple files with their own symbol 704 * tables and string tables. 705 * 706 * Note that we do not obey list locking protocols here. We really don't need 707 * DDB to hang because somebody's got the lock held. We'll take the chance 708 * that the files list is inconsistant instead. 709 */ 710 711int 712linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 713{ 714 linker_file_t lf; 715 716 TAILQ_FOREACH(lf, &linker_files, link) { 717 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 718 return (0); 719 } 720 return (ENOENT); 721} 722 723int 724linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 725{ 726 linker_file_t lf; 727 c_linker_sym_t best, es; 728 u_long diff, bestdiff, off; 729 730 best = 0; 731 off = (uintptr_t)value; 732 bestdiff = off; 733 TAILQ_FOREACH(lf, &linker_files, link) { 734 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 735 continue; 736 if (es != 0 && diff < bestdiff) { 737 best = es; 738 bestdiff = diff; 739 } 740 if (bestdiff == 0) 741 break; 742 } 743 if (best) { 744 *sym = best; 745 *diffp = bestdiff; 746 return (0); 747 } else { 748 *sym = 0; 749 *diffp = off; 750 return (ENOENT); 751 } 752} 753 754int 755linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 756{ 757 linker_file_t lf; 758 759 TAILQ_FOREACH(lf, &linker_files, link) { 760 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 761 return (0); 762 } 763 return (ENOENT); 764} 765#endif 766 767/* 768 * Syscalls. 769 */ 770/* 771 * MPSAFE 772 */ 773int 774kern_kldload(struct thread *td, const char *file, int *fileid) 775{ 776#ifdef HWPMC_HOOKS 777 struct pmckern_map_in pkm; 778#endif 779 const char *kldname, *modname; 780 linker_file_t lf; 781 int error; 782 783 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 784 return (error); 785 786 if ((error = suser(td)) != 0) 787 return (error); 788 789 /* 790 * If file does not contain qualified name or any dot in it 791 * (kldname.ko, or kldname.ver.ko) treat it as interface 792 * name. 793 */ 794 if (index(file, '/') || index(file, '.')) { 795 kldname = file; 796 modname = NULL; 797 } else { 798 kldname = NULL; 799 modname = file; 800 } 801 802 mtx_lock(&Giant); 803 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 804 if (error) 805 goto unlock; 806 807#ifdef HWPMC_HOOKS 808 pkm.pm_file = lf->filename; 809 pkm.pm_address = (uintptr_t) lf->address; 810 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 811#endif 812 lf->userrefs++; 813 if (fileid != NULL) 814 *fileid = lf->id; 815unlock: 816 mtx_unlock(&Giant); 817 return (error); 818} 819 820int 821kldload(struct thread *td, struct kldload_args *uap) 822{ 823 char *pathname = NULL; 824 int error, fileid; 825 826 td->td_retval[0] = -1; 827 828 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 829 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 830 if (error == 0) { 831 error = kern_kldload(td, pathname, &fileid); 832 if (error == 0) 833 td->td_retval[0] = fileid; 834 } 835 free(pathname, M_TEMP); 836 return (error); 837} 838 839/* 840 * MPSAFE 841 */ 842int 843kern_kldunload(struct thread *td, int fileid, int flags) 844{ 845#ifdef HWPMC_HOOKS 846 struct pmckern_map_out pkm; 847#endif 848 linker_file_t lf; 849 int error = 0; 850 851 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 852 return (error); 853 854 if ((error = suser(td)) != 0) 855 return (error); 856 857 mtx_lock(&Giant); 858 lf = linker_find_file_by_id(fileid); 859 if (lf) { 860 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 861 if (lf->userrefs == 0) { 862 /* 863 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 864 */ 865 printf("kldunload: attempt to unload file that was" 866 " loaded by the kernel\n"); 867 error = EBUSY; 868 } else { 869#ifdef HWPMC_HOOKS 870 /* Save data needed by hwpmc(4) before unloading. */ 871 pkm.pm_address = (uintptr_t) lf->address; 872 pkm.pm_size = lf->size; 873#endif 874 lf->userrefs--; 875 error = linker_file_unload(lf, flags); 876 if (error) 877 lf->userrefs++; 878 } 879 } else 880 error = ENOENT; 881 882#ifdef HWPMC_HOOKS 883 if (error == 0) 884 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 885#endif 886 mtx_unlock(&Giant); 887 return (error); 888} 889 890/* 891 * MPSAFE 892 */ 893int 894kldunload(struct thread *td, struct kldunload_args *uap) 895{ 896 897 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 898} 899 900/* 901 * MPSAFE 902 */ 903int 904kldunloadf(struct thread *td, struct kldunloadf_args *uap) 905{ 906 907 if (uap->flags != LINKER_UNLOAD_NORMAL && 908 uap->flags != LINKER_UNLOAD_FORCE) 909 return (EINVAL); 910 return (kern_kldunload(td, uap->fileid, uap->flags)); 911} 912 913/* 914 * MPSAFE 915 */ 916int 917kldfind(struct thread *td, struct kldfind_args *uap) 918{ 919 char *pathname; 920 const char *filename; 921 linker_file_t lf; 922 int error; 923 924#ifdef MAC 925 error = mac_check_kld_stat(td->td_ucred); 926 if (error) 927 return (error); 928#endif 929 930 mtx_lock(&Giant); 931 td->td_retval[0] = -1; 932 933 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 934 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 935 goto out; 936 937 filename = linker_basename(pathname); 938 lf = linker_find_file_by_name(filename); 939 if (lf) 940 td->td_retval[0] = lf->id; 941 else 942 error = ENOENT; 943out: 944 free(pathname, M_TEMP); 945 mtx_unlock(&Giant); 946 return (error); 947} 948 949/* 950 * MPSAFE 951 */ 952int 953kldnext(struct thread *td, struct kldnext_args *uap) 954{ 955 linker_file_t lf; 956 int error = 0; 957 958#ifdef MAC 959 error = mac_check_kld_stat(td->td_ucred); 960 if (error) 961 return (error); 962#endif 963 964 mtx_lock(&Giant); 965 966 if (uap->fileid == 0) { 967 mtx_lock(&kld_mtx); 968 if (TAILQ_FIRST(&linker_files)) 969 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 970 else 971 td->td_retval[0] = 0; 972 mtx_unlock(&kld_mtx); 973 goto out; 974 } 975 lf = linker_find_file_by_id(uap->fileid); 976 if (lf) { 977 if (TAILQ_NEXT(lf, link)) 978 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 979 else 980 td->td_retval[0] = 0; 981 } else 982 error = ENOENT; 983out: 984 mtx_unlock(&Giant); 985 return (error); 986} 987 988/* 989 * MPSAFE 990 */ 991int 992kldstat(struct thread *td, struct kldstat_args *uap) 993{ 994 struct kld_file_stat stat; 995 linker_file_t lf; 996 int error, namelen; 997 998 /* 999 * Check the version of the user's structure. 1000 */ 1001 error = copyin(uap->stat, &stat, sizeof(struct kld_file_stat)); 1002 if (error) 1003 return (error); 1004 if (stat.version != sizeof(struct kld_file_stat)) 1005 return (EINVAL); 1006 1007#ifdef MAC 1008 error = mac_check_kld_stat(td->td_ucred); 1009 if (error) 1010 return (error); 1011#endif 1012 1013 mtx_lock(&Giant); 1014 1015 lf = linker_find_file_by_id(uap->fileid); 1016 if (lf == NULL) { 1017 mtx_unlock(&Giant); 1018 return (ENOENT); 1019 } 1020 1021 namelen = strlen(lf->filename) + 1; 1022 if (namelen > MAXPATHLEN) 1023 namelen = MAXPATHLEN; 1024 bcopy(lf->filename, &stat.name[0], namelen); 1025 stat.refs = lf->refs; 1026 stat.id = lf->id; 1027 stat.address = lf->address; 1028 stat.size = lf->size; 1029 mtx_unlock(&Giant); 1030 1031 td->td_retval[0] = 0; 1032 1033 return (copyout(&stat, uap->stat, sizeof(struct kld_file_stat))); 1034} 1035 1036/* 1037 * MPSAFE 1038 */ 1039int 1040kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1041{ 1042 linker_file_t lf; 1043 module_t mp; 1044 int error = 0; 1045 1046#ifdef MAC 1047 error = mac_check_kld_stat(td->td_ucred); 1048 if (error) 1049 return (error); 1050#endif 1051 1052 mtx_lock(&Giant); 1053 lf = linker_find_file_by_id(uap->fileid); 1054 if (lf) { 1055 MOD_SLOCK; 1056 mp = TAILQ_FIRST(&lf->modules); 1057 if (mp != NULL) 1058 td->td_retval[0] = module_getid(mp); 1059 else 1060 td->td_retval[0] = 0; 1061 MOD_SUNLOCK; 1062 } else 1063 error = ENOENT; 1064 mtx_unlock(&Giant); 1065 return (error); 1066} 1067 1068/* 1069 * MPSAFE 1070 */ 1071int 1072kldsym(struct thread *td, struct kldsym_args *uap) 1073{ 1074 char *symstr = NULL; 1075 c_linker_sym_t sym; 1076 linker_symval_t symval; 1077 linker_file_t lf; 1078 struct kld_sym_lookup lookup; 1079 int error = 0; 1080 1081#ifdef MAC 1082 error = mac_check_kld_stat(td->td_ucred); 1083 if (error) 1084 return (error); 1085#endif 1086 1087 mtx_lock(&Giant); 1088 1089 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1090 goto out; 1091 if (lookup.version != sizeof(lookup) || 1092 uap->cmd != KLDSYM_LOOKUP) { 1093 error = EINVAL; 1094 goto out; 1095 } 1096 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1097 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1098 goto out; 1099 if (uap->fileid != 0) { 1100 lf = linker_find_file_by_id(uap->fileid); 1101 if (lf == NULL) { 1102 error = ENOENT; 1103 goto out; 1104 } 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, sizeof(lookup)); 1110 } else 1111 error = ENOENT; 1112 } else { 1113 mtx_lock(&kld_mtx); 1114 TAILQ_FOREACH(lf, &linker_files, link) { 1115 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1116 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1117 lookup.symvalue = (uintptr_t)symval.value; 1118 lookup.symsize = symval.size; 1119 error = copyout(&lookup, uap->data, 1120 sizeof(lookup)); 1121 break; 1122 } 1123 } 1124 mtx_unlock(&kld_mtx); 1125 if (lf == NULL) 1126 error = ENOENT; 1127 } 1128out: 1129 if (symstr) 1130 free(symstr, M_TEMP); 1131 mtx_unlock(&Giant); 1132 return (error); 1133} 1134 1135/* 1136 * Preloaded module support 1137 */ 1138 1139static modlist_t 1140modlist_lookup(const char *name, int ver) 1141{ 1142 modlist_t mod; 1143 1144 TAILQ_FOREACH(mod, &found_modules, link) { 1145 if (strcmp(mod->name, name) == 0 && 1146 (ver == 0 || mod->version == ver)) 1147 return (mod); 1148 } 1149 return (NULL); 1150} 1151 1152static modlist_t 1153modlist_lookup2(const char *name, struct mod_depend *verinfo) 1154{ 1155 modlist_t mod, bestmod; 1156 int ver; 1157 1158 if (verinfo == NULL) 1159 return (modlist_lookup(name, 0)); 1160 bestmod = NULL; 1161 TAILQ_FOREACH(mod, &found_modules, link) { 1162 if (strcmp(mod->name, name) != 0) 1163 continue; 1164 ver = mod->version; 1165 if (ver == verinfo->md_ver_preferred) 1166 return (mod); 1167 if (ver >= verinfo->md_ver_minimum && 1168 ver <= verinfo->md_ver_maximum && 1169 (bestmod == NULL || ver > bestmod->version)) 1170 bestmod = mod; 1171 } 1172 return (bestmod); 1173} 1174 1175static modlist_t 1176modlist_newmodule(const char *modname, int version, linker_file_t container) 1177{ 1178 modlist_t mod; 1179 1180 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1181 if (mod == NULL) 1182 panic("no memory for module list"); 1183 mod->container = container; 1184 mod->name = modname; 1185 mod->version = version; 1186 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1187 return (mod); 1188} 1189 1190static void 1191linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1192 struct mod_metadata **stop, int preload) 1193{ 1194 struct mod_metadata *mp, **mdp; 1195 const char *modname; 1196 int ver; 1197 1198 for (mdp = start; mdp < stop; mdp++) { 1199 mp = *mdp; 1200 if (mp->md_type != MDT_VERSION) 1201 continue; 1202 modname = mp->md_cval; 1203 ver = ((struct mod_version *)mp->md_data)->mv_version; 1204 if (modlist_lookup(modname, ver) != NULL) { 1205 printf("module %s already present!\n", modname); 1206 /* XXX what can we do? this is a build error. :-( */ 1207 continue; 1208 } 1209 modlist_newmodule(modname, ver, lf); 1210 } 1211} 1212 1213static void 1214linker_preload(void *arg) 1215{ 1216 caddr_t modptr; 1217 const char *modname, *nmodname; 1218 char *modtype; 1219 linker_file_t lf; 1220 linker_class_t lc; 1221 int error; 1222 linker_file_list_t loaded_files; 1223 linker_file_list_t depended_files; 1224 struct mod_metadata *mp, *nmp; 1225 struct mod_metadata **start, **stop, **mdp, **nmdp; 1226 struct mod_depend *verinfo; 1227 int nver; 1228 int resolves; 1229 modlist_t mod; 1230 struct sysinit **si_start, **si_stop; 1231 1232 TAILQ_INIT(&loaded_files); 1233 TAILQ_INIT(&depended_files); 1234 TAILQ_INIT(&found_modules); 1235 error = 0; 1236 1237 modptr = NULL; 1238 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1239 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1240 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1241 if (modname == NULL) { 1242 printf("Preloaded module at %p does not have a" 1243 " name!\n", modptr); 1244 continue; 1245 } 1246 if (modtype == NULL) { 1247 printf("Preloaded module at %p does not have a type!\n", 1248 modptr); 1249 continue; 1250 } 1251 if (bootverbose) 1252 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1253 modptr); 1254 lf = NULL; 1255 TAILQ_FOREACH(lc, &classes, link) { 1256 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1257 if (!error) 1258 break; 1259 lf = NULL; 1260 } 1261 if (lf) 1262 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1263 } 1264 1265 /* 1266 * First get a list of stuff in the kernel. 1267 */ 1268 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1269 &stop, NULL) == 0) 1270 linker_addmodules(linker_kernel_file, start, stop, 1); 1271 1272 /* 1273 * this is a once-off kinky bubble sort resolve relocation dependency 1274 * requirements 1275 */ 1276restart: 1277 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1278 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1279 &stop, NULL); 1280 /* 1281 * First, look to see if we would successfully link with this 1282 * stuff. 1283 */ 1284 resolves = 1; /* unless we know otherwise */ 1285 if (!error) { 1286 for (mdp = start; mdp < stop; mdp++) { 1287 mp = *mdp; 1288 if (mp->md_type != MDT_DEPEND) 1289 continue; 1290 modname = mp->md_cval; 1291 verinfo = mp->md_data; 1292 for (nmdp = start; nmdp < stop; nmdp++) { 1293 nmp = *nmdp; 1294 if (nmp->md_type != MDT_VERSION) 1295 continue; 1296 nmodname = nmp->md_cval; 1297 if (strcmp(modname, nmodname) == 0) 1298 break; 1299 } 1300 if (nmdp < stop) /* it's a self reference */ 1301 continue; 1302 1303 /* 1304 * ok, the module isn't here yet, we 1305 * are not finished 1306 */ 1307 if (modlist_lookup2(modname, verinfo) == NULL) 1308 resolves = 0; 1309 } 1310 } 1311 /* 1312 * OK, if we found our modules, we can link. So, "provide" 1313 * the modules inside and add it to the end of the link order 1314 * list. 1315 */ 1316 if (resolves) { 1317 if (!error) { 1318 for (mdp = start; mdp < stop; mdp++) { 1319 mp = *mdp; 1320 if (mp->md_type != MDT_VERSION) 1321 continue; 1322 modname = mp->md_cval; 1323 nver = ((struct mod_version *) 1324 mp->md_data)->mv_version; 1325 if (modlist_lookup(modname, 1326 nver) != NULL) { 1327 printf("module %s already" 1328 " present!\n", modname); 1329 linker_file_unload(lf, 1330 LINKER_UNLOAD_FORCE); 1331 TAILQ_REMOVE(&loaded_files, 1332 lf, loaded); 1333 /* we changed tailq next ptr */ 1334 goto restart; 1335 } 1336 modlist_newmodule(modname, nver, lf); 1337 } 1338 } 1339 TAILQ_REMOVE(&loaded_files, lf, loaded); 1340 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1341 /* 1342 * Since we provided modules, we need to restart the 1343 * sort so that the previous files that depend on us 1344 * have a chance. Also, we've busted the tailq next 1345 * pointer with the REMOVE. 1346 */ 1347 goto restart; 1348 } 1349 } 1350 1351 /* 1352 * At this point, we check to see what could not be resolved.. 1353 */ 1354 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1355 printf("KLD file %s is missing dependencies\n", lf->filename); 1356 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1357 TAILQ_REMOVE(&loaded_files, lf, loaded); 1358 } 1359 1360 /* 1361 * We made it. Finish off the linking in the order we determined. 1362 */ 1363 TAILQ_FOREACH(lf, &depended_files, loaded) { 1364 if (linker_kernel_file) { 1365 linker_kernel_file->refs++; 1366 error = linker_file_add_dependency(lf, 1367 linker_kernel_file); 1368 if (error) 1369 panic("cannot add dependency"); 1370 } 1371 lf->userrefs++; /* so we can (try to) kldunload it */ 1372 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1373 &stop, NULL); 1374 if (!error) { 1375 for (mdp = start; mdp < stop; mdp++) { 1376 mp = *mdp; 1377 if (mp->md_type != MDT_DEPEND) 1378 continue; 1379 modname = mp->md_cval; 1380 verinfo = mp->md_data; 1381 mod = modlist_lookup2(modname, verinfo); 1382 /* Don't count self-dependencies */ 1383 if (lf == mod->container) 1384 continue; 1385 mod->container->refs++; 1386 error = linker_file_add_dependency(lf, 1387 mod->container); 1388 if (error) 1389 panic("cannot add dependency"); 1390 } 1391 } 1392 /* 1393 * Now do relocation etc using the symbol search paths 1394 * established by the dependencies 1395 */ 1396 error = LINKER_LINK_PRELOAD_FINISH(lf); 1397 if (error) { 1398 printf("KLD file %s - could not finalize loading\n", 1399 lf->filename); 1400 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1401 continue; 1402 } 1403 linker_file_register_modules(lf); 1404 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1405 &si_stop, NULL) == 0) 1406 sysinit_add(si_start, si_stop); 1407 linker_file_register_sysctls(lf); 1408 lf->flags |= LINKER_FILE_LINKED; 1409 } 1410 /* woohoo! we made it! */ 1411} 1412 1413SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1414 1415/* 1416 * Search for a not-loaded module by name. 1417 * 1418 * Modules may be found in the following locations: 1419 * 1420 * - preloaded (result is just the module name) - on disk (result is full path 1421 * to module) 1422 * 1423 * If the module name is qualified in any way (contains path, etc.) the we 1424 * simply return a copy of it. 1425 * 1426 * The search path can be manipulated via sysctl. Note that we use the ';' 1427 * character as a separator to be consistent with the bootloader. 1428 */ 1429 1430static char linker_hintfile[] = "linker.hints"; 1431static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1432 1433SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1434 sizeof(linker_path), "module load search path"); 1435 1436TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1437 1438static char *linker_ext_list[] = { 1439 "", 1440 ".ko", 1441 NULL 1442}; 1443 1444/* 1445 * Check if file actually exists either with or without extension listed in 1446 * the linker_ext_list. (probably should be generic for the rest of the 1447 * kernel) 1448 */ 1449static char * 1450linker_lookup_file(const char *path, int pathlen, const char *name, 1451 int namelen, struct vattr *vap) 1452{ 1453 struct nameidata nd; 1454 struct thread *td = curthread; /* XXX */ 1455 char *result, **cpp, *sep; 1456 int error, len, extlen, reclen, flags; 1457 enum vtype type; 1458 1459 extlen = 0; 1460 for (cpp = linker_ext_list; *cpp; cpp++) { 1461 len = strlen(*cpp); 1462 if (len > extlen) 1463 extlen = len; 1464 } 1465 extlen++; /* trailing '\0' */ 1466 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1467 1468 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1469 result = malloc(reclen, M_LINKER, M_WAITOK); 1470 for (cpp = linker_ext_list; *cpp; cpp++) { 1471 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1472 namelen, name, *cpp); 1473 /* 1474 * Attempt to open the file, and return the path if 1475 * we succeed and it's a regular file. 1476 */ 1477 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1478 flags = FREAD; 1479 error = vn_open(&nd, &flags, 0, -1); 1480 if (error == 0) { 1481 NDFREE(&nd, NDF_ONLY_PNBUF); 1482 type = nd.ni_vp->v_type; 1483 if (vap) 1484 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1485 VOP_UNLOCK(nd.ni_vp, 0, td); 1486 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1487 if (type == VREG) 1488 return (result); 1489 } 1490 } 1491 free(result, M_LINKER); 1492 return (NULL); 1493} 1494 1495#define INT_ALIGN(base, ptr) ptr = \ 1496 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1497 1498/* 1499 * Lookup KLD which contains requested module in the "linker.hints" file. If 1500 * version specification is available, then try to find the best KLD. 1501 * Otherwise just find the latest one. 1502 */ 1503static char * 1504linker_hints_lookup(const char *path, int pathlen, const char *modname, 1505 int modnamelen, struct mod_depend *verinfo) 1506{ 1507 struct thread *td = curthread; /* XXX */ 1508 struct ucred *cred = td ? td->td_ucred : NULL; 1509 struct nameidata nd; 1510 struct vattr vattr, mattr; 1511 u_char *hints = NULL; 1512 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1513 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1514 1515 result = NULL; 1516 bestver = found = 0; 1517 1518 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1519 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1520 strlen(sep) + 1; 1521 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1522 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1523 linker_hintfile); 1524 1525 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1526 flags = FREAD; 1527 error = vn_open(&nd, &flags, 0, -1); 1528 if (error) 1529 goto bad; 1530 NDFREE(&nd, NDF_ONLY_PNBUF); 1531 if (nd.ni_vp->v_type != VREG) 1532 goto bad; 1533 best = cp = NULL; 1534 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1535 if (error) 1536 goto bad; 1537 /* 1538 * XXX: we need to limit this number to some reasonable value 1539 */ 1540 if (vattr.va_size > 100 * 1024) { 1541 printf("hints file too large %ld\n", (long)vattr.va_size); 1542 goto bad; 1543 } 1544 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1545 if (hints == NULL) 1546 goto bad; 1547 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1548 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1549 if (error) 1550 goto bad; 1551 VOP_UNLOCK(nd.ni_vp, 0, td); 1552 vn_close(nd.ni_vp, FREAD, cred, td); 1553 nd.ni_vp = NULL; 1554 if (reclen != 0) { 1555 printf("can't read %d\n", reclen); 1556 goto bad; 1557 } 1558 intp = (int *)hints; 1559 ival = *intp++; 1560 if (ival != LINKER_HINTS_VERSION) { 1561 printf("hints file version mismatch %d\n", ival); 1562 goto bad; 1563 } 1564 bufend = hints + vattr.va_size; 1565 recptr = (u_char *)intp; 1566 clen = blen = 0; 1567 while (recptr < bufend && !found) { 1568 intp = (int *)recptr; 1569 reclen = *intp++; 1570 ival = *intp++; 1571 cp = (char *)intp; 1572 switch (ival) { 1573 case MDT_VERSION: 1574 clen = *cp++; 1575 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1576 break; 1577 cp += clen; 1578 INT_ALIGN(hints, cp); 1579 ival = *(int *)cp; 1580 cp += sizeof(int); 1581 clen = *cp++; 1582 if (verinfo == NULL || 1583 ival == verinfo->md_ver_preferred) { 1584 found = 1; 1585 break; 1586 } 1587 if (ival >= verinfo->md_ver_minimum && 1588 ival <= verinfo->md_ver_maximum && 1589 ival > bestver) { 1590 bestver = ival; 1591 best = cp; 1592 blen = clen; 1593 } 1594 break; 1595 default: 1596 break; 1597 } 1598 recptr += reclen + sizeof(int); 1599 } 1600 /* 1601 * Finally check if KLD is in the place 1602 */ 1603 if (found) 1604 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1605 else if (best) 1606 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1607 1608 /* 1609 * KLD is newer than hints file. What we should do now? 1610 */ 1611 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1612 printf("warning: KLD '%s' is newer than the linker.hints" 1613 " file\n", result); 1614bad: 1615 free(pathbuf, M_LINKER); 1616 if (hints) 1617 free(hints, M_TEMP); 1618 if (nd.ni_vp != NULL) { 1619 VOP_UNLOCK(nd.ni_vp, 0, td); 1620 vn_close(nd.ni_vp, FREAD, cred, td); 1621 } 1622 /* 1623 * If nothing found or hints is absent - fallback to the old 1624 * way by using "kldname[.ko]" as module name. 1625 */ 1626 if (!found && !bestver && result == NULL) 1627 result = linker_lookup_file(path, pathlen, modname, 1628 modnamelen, NULL); 1629 return (result); 1630} 1631 1632/* 1633 * Lookup KLD which contains requested module in the all directories. 1634 */ 1635static char * 1636linker_search_module(const char *modname, int modnamelen, 1637 struct mod_depend *verinfo) 1638{ 1639 char *cp, *ep, *result; 1640 1641 /* 1642 * traverse the linker path 1643 */ 1644 for (cp = linker_path; *cp; cp = ep + 1) { 1645 /* find the end of this component */ 1646 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1647 result = linker_hints_lookup(cp, ep - cp, modname, 1648 modnamelen, verinfo); 1649 if (result != NULL) 1650 return (result); 1651 if (*ep == 0) 1652 break; 1653 } 1654 return (NULL); 1655} 1656 1657/* 1658 * Search for module in all directories listed in the linker_path. 1659 */ 1660static char * 1661linker_search_kld(const char *name) 1662{ 1663 char *cp, *ep, *result; 1664 int len; 1665 1666 /* qualified at all? */ 1667 if (index(name, '/')) 1668 return (linker_strdup(name)); 1669 1670 /* traverse the linker path */ 1671 len = strlen(name); 1672 for (ep = linker_path; *ep; ep++) { 1673 cp = ep; 1674 /* find the end of this component */ 1675 for (; *ep != 0 && *ep != ';'; ep++); 1676 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1677 if (result != NULL) 1678 return (result); 1679 } 1680 return (NULL); 1681} 1682 1683static const char * 1684linker_basename(const char *path) 1685{ 1686 const char *filename; 1687 1688 filename = rindex(path, '/'); 1689 if (filename == NULL) 1690 return path; 1691 if (filename[1]) 1692 filename++; 1693 return (filename); 1694} 1695 1696#ifdef HWPMC_HOOKS 1697 1698struct hwpmc_context { 1699 int nobjects; 1700 int nmappings; 1701 struct pmckern_map_in *kobase; 1702}; 1703 1704static int 1705linker_hwpmc_list_object(linker_file_t lf, void *arg) 1706{ 1707 struct hwpmc_context *hc; 1708 1709 hc = arg; 1710 1711 /* If we run out of mappings, fail. */ 1712 if (hc->nobjects >= hc->nmappings) 1713 return (1); 1714 1715 /* Save the info for this linker file. */ 1716 hc->kobase[hc->nobjects].pm_file = lf->filename; 1717 hc->kobase[hc->nobjects].pm_address = (uintptr_t)lf->address; 1718 hc->nobjects++; 1719 return (0); 1720} 1721 1722/* 1723 * Inform hwpmc about the set of kernel modules currently loaded. 1724 */ 1725void * 1726linker_hwpmc_list_objects(void) 1727{ 1728 struct hwpmc_context hc; 1729 1730 hc.nmappings = 15; /* a reasonable default */ 1731 1732 retry: 1733 /* allocate nmappings+1 entries */ 1734 MALLOC(hc.kobase, struct pmckern_map_in *, 1735 (hc.nmappings + 1) * sizeof(struct pmckern_map_in), M_LINKER, 1736 M_WAITOK | M_ZERO); 1737 1738 hc.nobjects = 0; 1739 if (linker_file_foreach(linker_hwpmc_list_object, &hc) != 0) { 1740 hc.nmappings = hc.nobjects; 1741 FREE(hc.kobase, M_LINKER); 1742 goto retry; 1743 } 1744 1745 KASSERT(hc.nobjects > 0, ("linker_hpwmc_list_objects: no kernel " 1746 "objects?")); 1747 1748 /* The last entry of the malloced area comprises of all zeros. */ 1749 KASSERT(hc.kobase[hc.nobjects].pm_file == NULL, 1750 ("linker_hwpmc_list_objects: last object not NULL")); 1751 1752 return ((void *)hc.kobase); 1753} 1754#endif 1755 1756/* 1757 * Find a file which contains given module and load it, if "parent" is not 1758 * NULL, register a reference to it. 1759 */ 1760static int 1761linker_load_module(const char *kldname, const char *modname, 1762 struct linker_file *parent, struct mod_depend *verinfo, 1763 struct linker_file **lfpp) 1764{ 1765 linker_file_t lfdep; 1766 const char *filename; 1767 char *pathname; 1768 int error; 1769 1770 if (modname == NULL) { 1771 /* 1772 * We have to load KLD 1773 */ 1774 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1775 " is not NULL")); 1776 pathname = linker_search_kld(kldname); 1777 } else { 1778 if (modlist_lookup2(modname, verinfo) != NULL) 1779 return (EEXIST); 1780 if (kldname != NULL) 1781 pathname = linker_strdup(kldname); 1782 else if (rootvnode == NULL) 1783 pathname = NULL; 1784 else 1785 /* 1786 * Need to find a KLD with required module 1787 */ 1788 pathname = linker_search_module(modname, 1789 strlen(modname), verinfo); 1790 } 1791 if (pathname == NULL) 1792 return (ENOENT); 1793 1794 /* 1795 * Can't load more than one file with the same basename XXX: 1796 * Actually it should be possible to have multiple KLDs with 1797 * the same basename but different path because they can 1798 * provide different versions of the same modules. 1799 */ 1800 filename = linker_basename(pathname); 1801 if (linker_find_file_by_name(filename)) 1802 error = EEXIST; 1803 else do { 1804 error = linker_load_file(pathname, &lfdep); 1805 if (error) 1806 break; 1807 if (modname && verinfo && 1808 modlist_lookup2(modname, verinfo) == NULL) { 1809 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1810 error = ENOENT; 1811 break; 1812 } 1813 if (parent) { 1814 error = linker_file_add_dependency(parent, lfdep); 1815 if (error) 1816 break; 1817 } 1818 if (lfpp) 1819 *lfpp = lfdep; 1820 } while (0); 1821 free(pathname, M_LINKER); 1822 return (error); 1823} 1824 1825/* 1826 * This routine is responsible for finding dependencies of userland initiated 1827 * kldload(2)'s of files. 1828 */ 1829int 1830linker_load_dependencies(linker_file_t lf) 1831{ 1832 linker_file_t lfdep; 1833 struct mod_metadata **start, **stop, **mdp, **nmdp; 1834 struct mod_metadata *mp, *nmp; 1835 struct mod_depend *verinfo; 1836 modlist_t mod; 1837 const char *modname, *nmodname; 1838 int ver, error = 0, count; 1839 1840 /* 1841 * All files are dependant on /kernel. 1842 */ 1843 if (linker_kernel_file) { 1844 linker_kernel_file->refs++; 1845 error = linker_file_add_dependency(lf, linker_kernel_file); 1846 if (error) 1847 return (error); 1848 } 1849 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1850 &count) != 0) 1851 return (0); 1852 for (mdp = start; mdp < stop; mdp++) { 1853 mp = *mdp; 1854 if (mp->md_type != MDT_VERSION) 1855 continue; 1856 modname = mp->md_cval; 1857 ver = ((struct mod_version *)mp->md_data)->mv_version; 1858 mod = modlist_lookup(modname, ver); 1859 if (mod != NULL) { 1860 printf("interface %s.%d already present in the KLD" 1861 " '%s'!\n", modname, ver, 1862 mod->container->filename); 1863 return (EEXIST); 1864 } 1865 } 1866 1867 for (mdp = start; mdp < stop; mdp++) { 1868 mp = *mdp; 1869 if (mp->md_type != MDT_DEPEND) 1870 continue; 1871 modname = mp->md_cval; 1872 verinfo = mp->md_data; 1873 nmodname = NULL; 1874 for (nmdp = start; nmdp < stop; nmdp++) { 1875 nmp = *nmdp; 1876 if (nmp->md_type != MDT_VERSION) 1877 continue; 1878 nmodname = nmp->md_cval; 1879 if (strcmp(modname, nmodname) == 0) 1880 break; 1881 } 1882 if (nmdp < stop)/* early exit, it's a self reference */ 1883 continue; 1884 mod = modlist_lookup2(modname, verinfo); 1885 if (mod) { /* woohoo, it's loaded already */ 1886 lfdep = mod->container; 1887 lfdep->refs++; 1888 error = linker_file_add_dependency(lf, lfdep); 1889 if (error) 1890 break; 1891 continue; 1892 } 1893 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1894 if (error) { 1895 printf("KLD %s: depends on %s - not available\n", 1896 lf->filename, modname); 1897 break; 1898 } 1899 } 1900 1901 if (error) 1902 return (error); 1903 linker_addmodules(lf, start, stop, 0); 1904 return (error); 1905} 1906 1907static int 1908sysctl_kern_function_list_iterate(const char *name, void *opaque) 1909{ 1910 struct sysctl_req *req; 1911 1912 req = opaque; 1913 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1914} 1915 1916/* 1917 * Export a nul-separated, double-nul-terminated list of all function names 1918 * in the kernel. 1919 */ 1920static int 1921sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1922{ 1923 linker_file_t lf; 1924 int error; 1925 1926#ifdef MAC 1927 error = mac_check_kld_stat(req->td->td_ucred); 1928 if (error) 1929 return (error); 1930#endif 1931 error = sysctl_wire_old_buffer(req, 0); 1932 if (error != 0) 1933 return (error); 1934 mtx_lock(&kld_mtx); 1935 TAILQ_FOREACH(lf, &linker_files, link) { 1936 error = LINKER_EACH_FUNCTION_NAME(lf, 1937 sysctl_kern_function_list_iterate, req); 1938 if (error) { 1939 mtx_unlock(&kld_mtx); 1940 return (error); 1941 } 1942 } 1943 mtx_unlock(&kld_mtx); 1944 return (SYSCTL_OUT(req, "", 1)); 1945} 1946 1947SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1948 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 1949