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 * $FreeBSD$ 27 */ 28 29 #include "opt_ddb.h" 30 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/systm.h> 34 #include <sys/malloc.h> 35 #include <sys/sysproto.h> 36 #include <sys/sysent.h> 37 #include <sys/proc.h> 38 #include <sys/lock.h> 39 #include <sys/module.h> 40 #include <sys/linker.h> 41 #include <sys/fcntl.h> 42 #include <sys/libkern.h> 43 #include <sys/namei.h> 44 #include <sys/vnode.h> 45 #include <sys/sysctl.h> 46 47 48 #include "linker_if.h" 49 50 #ifdef KLD_DEBUG 51 int kld_debug = 0; 52 #endif 53 54 static char *linker_search_path(const char *name); 55 static const char *linker_basename(const char* path); 56 57 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 58 59 linker_file_t linker_kernel_file; 60 61 static struct lock lock; /* lock for the file list */ 62 static linker_class_list_t classes; 63 static linker_file_list_t linker_files; 64 static int next_file_id = 1; 65 66 /* XXX wrong name; we're looking at version provision tags here, not modules */ 67 typedef TAILQ_HEAD(, modlist) modlisthead_t; 68 struct modlist { 69 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 70 linker_file_t container; 71 const char *name; 72 }; 73 typedef struct modlist *modlist_t; 74 static modlisthead_t found_modules; 75 76 static char * 77 linker_strdup(const char *str) 78 { 79 char *result; 80 81 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 82 strcpy(result, str); 83 return(result); 84 } 85 86 static void 87 linker_init(void* arg) 88 { 89 lockinit(&lock, PVM, "klink", 0, 0); 90 TAILQ_INIT(&classes); 91 TAILQ_INIT(&linker_files); 92 } 93 94 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); 95 96 int 97 linker_add_class(linker_class_t lc) 98 { 99 kobj_class_compile((kobj_class_t) lc); 100 TAILQ_INSERT_TAIL(&classes, lc, link); 101 return 0; 102 } 103 104 static void 105 linker_file_sysinit(linker_file_t lf) 106 { 107 struct linker_set* sysinits; 108 struct sysinit** sipp; 109 struct sysinit** xipp; 110 struct sysinit* save; 111 112 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 113 lf->filename)); 114 115 sysinits = (struct linker_set*) 116 linker_file_lookup_symbol(lf, "sysinit_set", 0); 117 118 KLD_DPF(FILE, ("linker_file_sysinit: SYSINITs %p\n", sysinits)); 119 if (!sysinits) 120 return; 121 /* 122 * Perform a bubble sort of the system initialization objects by 123 * their subsystem (primary key) and order (secondary key). 124 * 125 * Since some things care about execution order, this is the 126 * operation which ensures continued function. 127 */ 128 for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { 129 for (xipp = sipp + 1; *xipp; xipp++) { 130 if ((*sipp)->subsystem < (*xipp)->subsystem || 131 ((*sipp)->subsystem == (*xipp)->subsystem && 132 (*sipp)->order <= (*xipp)->order)) 133 continue; /* skip*/ 134 save = *sipp; 135 *sipp = *xipp; 136 *xipp = save; 137 } 138 } 139 140 141 /* 142 * Traverse the (now) ordered list of system initialization tasks. 143 * Perform each task, and continue on to the next task. 144 */ 145 for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { 146 if ((*sipp)->subsystem == SI_SUB_DUMMY) 147 continue; /* skip dummy task(s)*/ 148 149 /* Call function */ 150 (*((*sipp)->func))((*sipp)->udata); 151 } 152 } 153 154 static void 155 linker_file_sysuninit(linker_file_t lf) 156 { 157 struct linker_set* sysuninits; 158 struct sysinit** sipp; 159 struct sysinit** xipp; 160 struct sysinit* save; 161 162 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 163 lf->filename)); 164 165 sysuninits = (struct linker_set*) 166 linker_file_lookup_symbol(lf, "sysuninit_set", 0); 167 168 KLD_DPF(FILE, ("linker_file_sysuninit: SYSUNINITs %p\n", sysuninits)); 169 if (!sysuninits) 170 return; 171 172 /* 173 * Perform a reverse bubble sort of the system initialization objects 174 * by their subsystem (primary key) and order (secondary key). 175 * 176 * Since some things care about execution order, this is the 177 * operation which ensures continued function. 178 */ 179 for (sipp = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { 180 for (xipp = sipp + 1; *xipp; xipp++) { 181 if ((*sipp)->subsystem > (*xipp)->subsystem || 182 ((*sipp)->subsystem == (*xipp)->subsystem && 183 (*sipp)->order >= (*xipp)->order)) 184 continue; /* skip*/ 185 save = *sipp; 186 *sipp = *xipp; 187 *xipp = save; 188 } 189 } 190 191 /* 192 * Traverse the (now) ordered list of system initialization tasks. 193 * Perform each task, and continue on to the next task. 194 */ 195 for (sipp = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { 196 if ((*sipp)->subsystem == SI_SUB_DUMMY) 197 continue; /* skip dummy task(s)*/ 198 199 /* Call function */ 200 (*((*sipp)->func))((*sipp)->udata); 201 } 202 } 203 204 static void 205 linker_file_register_sysctls(linker_file_t lf) 206 { 207 struct linker_set* sysctls; 208 209 KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 210 lf->filename)); 211 212 sysctls = (struct linker_set*) 213 linker_file_lookup_symbol(lf, "sysctl_set", 0); 214 215 KLD_DPF(FILE, ("linker_file_register_sysctls: SYSCTLs %p\n", sysctls)); 216 if (!sysctls) 217 return; 218 219 sysctl_register_set(sysctls); 220 } 221 222 static void 223 linker_file_unregister_sysctls(linker_file_t lf) 224 { 225 struct linker_set* sysctls; 226 227 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n", 228 lf->filename)); 229 230 sysctls = (struct linker_set*) 231 linker_file_lookup_symbol(lf, "sysctl_set", 0); 232 233 KLD_DPF(FILE, ("linker_file_unregister_sysctls: SYSCTLs %p\n", sysctls)); 234 if (!sysctls) 235 return; 236 237 sysctl_unregister_set(sysctls); 238 } 239 240 extern struct linker_set modmetadata_set; 241 242 static int 243 linker_file_register_modules(linker_file_t lf) 244 { 245 int error, mcount; 246 struct linker_set *modules; 247 struct mod_metadata **mdpp; 248 const moduledata_t *moddata; 249 struct sysinit **sipp; 250 251 KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n", 252 lf->filename)); 253 254 modules = (struct linker_set*) 255 linker_file_lookup_symbol(lf, "modmetadata_set", 0); 256 257 if (!modules && lf == linker_kernel_file) 258 modules = &modmetadata_set; 259 260 mcount = 0; 261 if (modules) { 262 for (mdpp = (struct mod_metadata**)modules->ls_items; *mdpp; mdpp++) { 263 if ((*mdpp)->md_type != MDT_MODULE) 264 continue; 265 mcount++; 266 moddata = (*mdpp)->md_data; 267 KLD_DPF(FILE, ("Registering module %s in %s\n", 268 moddata->name, lf->filename)); 269 error = module_register(moddata, lf); 270 if (error) 271 printf("Module %s failed to register: %d\n", moddata->name, error); 272 } 273 } 274 if (mcount) 275 return mcount; /* Do not mix old and new style */ 276 277 /* Hack - handle old kld's without metadata */ 278 modules = (struct linker_set*) 279 linker_file_lookup_symbol(lf, "sysinit_set", 0); 280 if (modules) { 281 for (sipp = (struct sysinit **)modules->ls_items; *sipp; sipp++) { 282 if ((*sipp)->func != module_register_init) 283 continue; 284 mcount++; 285 moddata = (*sipp)->udata; 286 printf("Old-style KLD file %s found\n", moddata->name); 287 error = module_register(moddata, lf); 288 if (error) 289 printf("Old-style KLD file %s failed to register: %d\n", moddata->name, error); 290 } 291 } 292 return mcount; 293 } 294 295 static void 296 linker_init_kernel_modules(void) 297 { 298 linker_file_register_modules(linker_kernel_file); 299 } 300 301 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0); 302 303 int 304 linker_load_file(const char* filename, linker_file_t* result) 305 { 306 linker_class_t lc; 307 linker_file_t lf; 308 int foundfile, error = 0; 309 310 /* Refuse to load modules if securelevel raised */ 311 if (securelevel > 0) 312 return EPERM; 313 314 lf = linker_find_file_by_name(filename); 315 if (lf) { 316 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename)); 317 *result = lf; 318 lf->refs++; 319 goto out; 320 } 321 322 lf = NULL; 323 foundfile = 0; 324 TAILQ_FOREACH(lc, &classes, link) { 325 KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", 326 filename, lc->desc)); 327 error = LINKER_LOAD_FILE(lc, filename, &lf); 328 /* 329 * If we got something other than ENOENT, then it exists but we cannot 330 * load it for some other reason. 331 */ 332 if (error != ENOENT) 333 foundfile = 1; 334 if (lf) { 335 linker_file_register_modules(lf); 336 linker_file_register_sysctls(lf); 337 linker_file_sysinit(lf); 338 lf->flags |= LINKER_FILE_LINKED; 339 340 *result = lf; 341 error = 0; 342 goto out; 343 } 344 } 345 /* 346 * Less than ideal, but tells the user whether it failed to load or 347 * the module was not found. 348 */ 349 if (foundfile) 350 error = ENOEXEC; /* Format not recognised (or unloadable) */ 351 else 352 error = ENOENT; /* Nothing found */ 353 354 out: 355 return error; 356 } 357 358 linker_file_t 359 linker_find_file_by_name(const char* filename) 360 { 361 linker_file_t lf = 0; 362 char *koname; 363 364 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 365 if (koname == NULL) 366 goto out; 367 sprintf(koname, "%s.ko", filename); 368 369 lockmgr(&lock, LK_SHARED, 0, curproc); 370 TAILQ_FOREACH(lf, &linker_files, link) { 371 if (!strcmp(lf->filename, koname)) 372 break; 373 if (!strcmp(lf->filename, filename)) 374 break; 375 } 376 lockmgr(&lock, LK_RELEASE, 0, curproc); 377 378 out: 379 if (koname) 380 free(koname, M_LINKER); 381 return lf; 382 } 383 384 linker_file_t 385 linker_find_file_by_id(int fileid) 386 { 387 linker_file_t lf = 0; 388 389 lockmgr(&lock, LK_SHARED, 0, curproc); 390 TAILQ_FOREACH(lf, &linker_files, link) 391 if (lf->id == fileid) 392 break; 393 lockmgr(&lock, LK_RELEASE, 0, curproc); 394 395 return lf; 396 } 397 398 linker_file_t 399 linker_make_file(const char* pathname, linker_class_t lc) 400 { 401 linker_file_t lf = 0; 402 const char *filename; 403 404 filename = linker_basename(pathname); 405 406 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 407 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 408 lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK); 409 if (!lf) 410 goto out; 411 412 lf->refs = 1; 413 lf->userrefs = 0; 414 lf->flags = 0; 415 lf->filename = linker_strdup(filename); 416 lf->id = next_file_id++; 417 lf->ndeps = 0; 418 lf->deps = NULL; 419 STAILQ_INIT(&lf->common); 420 TAILQ_INIT(&lf->modules); 421 422 TAILQ_INSERT_TAIL(&linker_files, lf, link); 423 424 out: 425 lockmgr(&lock, LK_RELEASE, 0, curproc); 426 return lf; 427 } 428 429 int 430 linker_file_unload(linker_file_t file) 431 { 432 module_t mod, next; 433 modlist_t ml, nextml; 434 struct common_symbol* cp; 435 int error = 0; 436 int i; 437 438 /* Refuse to unload modules if securelevel raised */ 439 if (securelevel > 0) 440 return EPERM; 441 442 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 443 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 444 if (file->refs == 1) { 445 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); 446 /* 447 * Inform any modules associated with this file. 448 */ 449 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 450 next = module_getfnext(mod); 451 452 /* 453 * Give the module a chance to veto the unload. 454 */ 455 if ((error = module_unload(mod)) != 0) { 456 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", 457 mod)); 458 lockmgr(&lock, LK_RELEASE, 0, curproc); 459 goto out; 460 } 461 462 module_release(mod); 463 } 464 } 465 466 file->refs--; 467 if (file->refs > 0) { 468 lockmgr(&lock, LK_RELEASE, 0, curproc); 469 goto out; 470 } 471 472 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 473 nextml = TAILQ_NEXT(ml, link); 474 if (ml->container == file) { 475 TAILQ_REMOVE(&found_modules, ml, link); 476 } 477 } 478 479 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ 480 if (file->flags & LINKER_FILE_LINKED) { 481 linker_file_sysuninit(file); 482 linker_file_unregister_sysctls(file); 483 } 484 485 TAILQ_REMOVE(&linker_files, file, link); 486 lockmgr(&lock, LK_RELEASE, 0, curproc); 487 488 if (file->deps) { 489 for (i = 0; i < file->ndeps; i++) 490 linker_file_unload(file->deps[i]); 491 free(file->deps, M_LINKER); 492 file->deps = NULL; 493 } 494 495 for (cp = STAILQ_FIRST(&file->common); cp; 496 cp = STAILQ_FIRST(&file->common)) { 497 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 498 free(cp, M_LINKER); 499 } 500 501 LINKER_UNLOAD(file); 502 if (file->filename) { 503 free(file->filename, M_LINKER); 504 file->filename = NULL; 505 } 506 kobj_delete((kobj_t) file, M_LINKER); 507 508 out: 509 return error; 510 } 511 512 int 513 linker_file_add_dependancy(linker_file_t file, linker_file_t dep) 514 { 515 linker_file_t* newdeps; 516 517 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*), 518 M_LINKER, M_WAITOK | M_ZERO); 519 if (newdeps == NULL) 520 return ENOMEM; 521 522 if (file->deps) { 523 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); 524 free(file->deps, M_LINKER); 525 } 526 file->deps = newdeps; 527 file->deps[file->ndeps] = dep; 528 file->ndeps++; 529 530 return 0; 531 } 532 533 caddr_t 534 linker_file_lookup_symbol(linker_file_t file, const char* name, int deps) 535 { 536 c_linker_sym_t sym; 537 linker_symval_t symval; 538 caddr_t address; 539 size_t common_size = 0; 540 int i; 541 542 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 543 file, name, deps)); 544 545 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 546 LINKER_SYMBOL_VALUES(file, sym, &symval); 547 if (symval.value == 0) 548 /* 549 * For commons, first look them up in the dependancies and 550 * only allocate space if not found there. 551 */ 552 common_size = symval.size; 553 else { 554 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); 555 return symval.value; 556 } 557 } 558 559 if (deps) { 560 for (i = 0; i < file->ndeps; i++) { 561 address = linker_file_lookup_symbol(file->deps[i], name, 0); 562 if (address) { 563 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address)); 564 return address; 565 } 566 } 567 } 568 569 if (common_size > 0) { 570 /* 571 * This is a common symbol which was not found in the 572 * dependancies. We maintain a simple common symbol table in 573 * the file object. 574 */ 575 struct common_symbol* cp; 576 577 STAILQ_FOREACH(cp, &file->common, link) 578 if (!strcmp(cp->name, name)) { 579 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); 580 return cp->address; 581 } 582 583 /* 584 * Round the symbol size up to align. 585 */ 586 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 587 cp = malloc(sizeof(struct common_symbol) 588 + common_size 589 + strlen(name) + 1, 590 M_LINKER, M_WAITOK | M_ZERO); 591 if (!cp) { 592 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 593 return 0; 594 } 595 596 cp->address = (caddr_t) (cp + 1); 597 cp->name = cp->address + common_size; 598 strcpy(cp->name, name); 599 bzero(cp->address, common_size); 600 STAILQ_INSERT_TAIL(&file->common, cp, link); 601 602 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); 603 return cp->address; 604 } 605 606 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 607 return 0; 608 } 609 610 #ifdef DDB 611 /* 612 * DDB Helpers. DDB has to look across multiple files with their own 613 * symbol tables and string tables. 614 * 615 * Note that we do not obey list locking protocols here. We really don't 616 * need DDB to hang because somebody's got the lock held. We'll take the 617 * chance that the files list is inconsistant instead. 618 */ 619 620 int 621 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 622 { 623 linker_file_t lf; 624 625 TAILQ_FOREACH(lf, &linker_files, link) { 626 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 627 return 0; 628 } 629 return ENOENT; 630 } 631 632 int 633 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 634 { 635 linker_file_t lf; 636 u_long off = (uintptr_t)value; 637 u_long diff, bestdiff; 638 c_linker_sym_t best; 639 c_linker_sym_t es; 640 641 best = 0; 642 bestdiff = off; 643 TAILQ_FOREACH(lf, &linker_files, link) { 644 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 645 continue; 646 if (es != 0 && diff < bestdiff) { 647 best = es; 648 bestdiff = diff; 649 } 650 if (bestdiff == 0) 651 break; 652 } 653 if (best) { 654 *sym = best; 655 *diffp = bestdiff; 656 return 0; 657 } else { 658 *sym = 0; 659 *diffp = off; 660 return ENOENT; 661 } 662 } 663 664 int 665 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 666 { 667 linker_file_t lf; 668 669 TAILQ_FOREACH(lf, &linker_files, link) { 670 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 671 return 0; 672 } 673 return ENOENT; 674 } 675 676 #endif 677 678 /* 679 * Syscalls. 680 */ 681 682 int 683 kldload(struct proc* p, struct kldload_args* uap) 684 { 685 char* pathname, *realpath; 686 const char *filename; 687 linker_file_t lf; 688 int error = 0; 689 690 p->p_retval[0] = -1; 691 692 if (securelevel > 0) /* redundant, but that's OK */ 693 return EPERM; 694 695 if ((error = suser(p)) != 0) 696 return error; 697 698 realpath = NULL; 699 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 700 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 701 goto out; 702 703 realpath = linker_search_path(pathname); 704 if (realpath == NULL) { 705 error = ENOENT; 706 goto out; 707 } 708 /* Can't load more than one file with the same name */ 709 filename = linker_basename(realpath); 710 if (linker_find_file_by_name(filename)) { 711 error = EEXIST; 712 goto out; 713 } 714 715 if ((error = linker_load_file(realpath, &lf)) != 0) 716 goto out; 717 718 lf->userrefs++; 719 p->p_retval[0] = lf->id; 720 721 out: 722 if (pathname) 723 free(pathname, M_TEMP); 724 if (realpath) 725 free(realpath, M_LINKER); 726 return error; 727 } 728 729 int 730 kldunload(struct proc* p, struct kldunload_args* uap) 731 { 732 linker_file_t lf; 733 int error = 0; 734 735 if (securelevel > 0) /* redundant, but that's OK */ 736 return EPERM; 737 738 if ((error = suser(p)) != 0) 739 return error; 740 741 lf = linker_find_file_by_id(SCARG(uap, fileid)); 742 if (lf) { 743 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 744 if (lf->userrefs == 0) { 745 printf("kldunload: attempt to unload file that was loaded by the kernel\n"); 746 error = EBUSY; 747 goto out; 748 } 749 lf->userrefs--; 750 error = linker_file_unload(lf); 751 if (error) 752 lf->userrefs++; 753 } else 754 error = ENOENT; 755 756 out: 757 return error; 758 } 759 760 int 761 kldfind(struct proc* p, struct kldfind_args* uap) 762 { 763 char* pathname; 764 const char *filename; 765 linker_file_t lf; 766 int error = 0; 767 768 p->p_retval[0] = -1; 769 770 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 771 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 772 goto out; 773 774 filename = linker_basename(pathname); 775 776 lf = linker_find_file_by_name(filename); 777 if (lf) 778 p->p_retval[0] = lf->id; 779 else 780 error = ENOENT; 781 782 out: 783 if (pathname) 784 free(pathname, M_TEMP); 785 return error; 786 } 787 788 int 789 kldnext(struct proc* p, struct kldnext_args* uap) 790 { 791 linker_file_t lf; 792 int error = 0; 793 794 if (SCARG(uap, fileid) == 0) { 795 if (TAILQ_FIRST(&linker_files)) 796 p->p_retval[0] = TAILQ_FIRST(&linker_files)->id; 797 else 798 p->p_retval[0] = 0; 799 return 0; 800 } 801 802 lf = linker_find_file_by_id(SCARG(uap, fileid)); 803 if (lf) { 804 if (TAILQ_NEXT(lf, link)) 805 p->p_retval[0] = TAILQ_NEXT(lf, link)->id; 806 else 807 p->p_retval[0] = 0; 808 } else 809 error = ENOENT; 810 811 return error; 812 } 813 814 int 815 kldstat(struct proc* p, struct kldstat_args* uap) 816 { 817 linker_file_t lf; 818 int error = 0; 819 int version; 820 struct kld_file_stat* stat; 821 int namelen; 822 823 lf = linker_find_file_by_id(SCARG(uap, fileid)); 824 if (!lf) { 825 error = ENOENT; 826 goto out; 827 } 828 829 stat = SCARG(uap, stat); 830 831 /* 832 * Check the version of the user's structure. 833 */ 834 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 835 goto out; 836 if (version != sizeof(struct kld_file_stat)) { 837 error = EINVAL; 838 goto out; 839 } 840 841 namelen = strlen(lf->filename) + 1; 842 if (namelen > MAXPATHLEN) 843 namelen = MAXPATHLEN; 844 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 845 goto out; 846 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 847 goto out; 848 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 849 goto out; 850 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0) 851 goto out; 852 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 853 goto out; 854 855 p->p_retval[0] = 0; 856 857 out: 858 return error; 859 } 860 861 int 862 kldfirstmod(struct proc* p, struct kldfirstmod_args* uap) 863 { 864 linker_file_t lf; 865 int error = 0; 866 867 lf = linker_find_file_by_id(SCARG(uap, fileid)); 868 if (lf) { 869 if (TAILQ_FIRST(&lf->modules)) 870 p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules)); 871 else 872 p->p_retval[0] = 0; 873 } else 874 error = ENOENT; 875 876 return error; 877 } 878 879 int 880 kldsym(struct proc *p, struct kldsym_args *uap) 881 { 882 char *symstr = NULL; 883 c_linker_sym_t sym; 884 linker_symval_t symval; 885 linker_file_t lf; 886 struct kld_sym_lookup lookup; 887 int error = 0; 888 889 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0) 890 goto out; 891 if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) { 892 error = EINVAL; 893 goto out; 894 } 895 896 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 897 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 898 goto out; 899 900 if (SCARG(uap, fileid) != 0) { 901 lf = linker_find_file_by_id(SCARG(uap, fileid)); 902 if (lf == NULL) { 903 error = ENOENT; 904 goto out; 905 } 906 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 907 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 908 lookup.symvalue = (uintptr_t)symval.value; 909 lookup.symsize = symval.size; 910 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 911 } else 912 error = ENOENT; 913 } else { 914 TAILQ_FOREACH(lf, &linker_files, link) { 915 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 916 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 917 lookup.symvalue = (uintptr_t)symval.value; 918 lookup.symsize = symval.size; 919 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 920 break; 921 } 922 } 923 if (!lf) 924 error = ENOENT; 925 } 926 out: 927 if (symstr) 928 free(symstr, M_TEMP); 929 return error; 930 } 931 932 /* 933 * Preloaded module support 934 */ 935 936 static modlist_t 937 modlist_lookup(const char *name) 938 { 939 modlist_t mod; 940 941 TAILQ_FOREACH(mod, &found_modules, link) { 942 if (!strcmp(mod->name, name)) 943 return mod; 944 } 945 return NULL; 946 } 947 948 /* 949 * This routine is cheap and nasty but will work for data pointers. 950 */ 951 static void * 952 linker_reloc_ptr(linker_file_t lf, void *offset) 953 { 954 return lf->address + (uintptr_t)offset; 955 } 956 957 static void 958 linker_preload(void* arg) 959 { 960 caddr_t modptr; 961 char *modname, *nmodname; 962 char *modtype; 963 linker_file_t lf; 964 linker_class_t lc; 965 int error, mcount; 966 struct linker_set *sysinits; 967 linker_file_list_t loaded_files; 968 linker_file_list_t depended_files; 969 struct linker_set *deps; 970 struct mod_metadata *mp, *nmp; 971 int i, j; 972 int resolves; 973 modlist_t mod; 974 975 TAILQ_INIT(&loaded_files); 976 TAILQ_INIT(&depended_files); 977 TAILQ_INIT(&found_modules); 978 error = 0; 979 980 modptr = NULL; 981 while ((modptr = preload_search_next_name(modptr)) != NULL) { 982 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 983 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 984 if (modname == NULL) { 985 printf("Preloaded module at %p does not have a name!\n", modptr); 986 continue; 987 } 988 if (modtype == NULL) { 989 printf("Preloaded module at %p does not have a type!\n", modptr); 990 continue; 991 } 992 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr); 993 lf = NULL; 994 TAILQ_FOREACH(lc, &classes, link) { 995 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 996 if (error) { 997 lf = NULL; 998 break; 999 } 1000 } 1001 if (lf) 1002 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1003 } 1004 1005 /* 1006 * First get a list of stuff in the kernel. 1007 */ 1008 deps = (struct linker_set*) 1009 linker_file_lookup_symbol(linker_kernel_file, MDT_SETNAME, 0); 1010 if (deps) { 1011 for (i = 0; i < deps->ls_length; i++) { 1012 mp = deps->ls_items[i]; 1013 if (mp->md_type != MDT_VERSION) 1014 continue; 1015 modname = mp->md_cval; 1016 if (modlist_lookup(modname) != NULL) { 1017 printf("module %s already present!\n", modname); 1018 /* XXX what can we do? this is a build error. :-( */ 1019 continue; 1020 } 1021 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); 1022 if (mod == NULL) 1023 panic("no memory for module list"); 1024 mod->container = linker_kernel_file; 1025 mod->name = modname; 1026 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1027 } 1028 } 1029 1030 /* 1031 * this is a once-off kinky bubble sort 1032 * resolve relocation dependency requirements 1033 */ 1034 restart: 1035 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1036 deps = (struct linker_set*) 1037 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1038 /* 1039 * First, look to see if we would successfully link with this stuff. 1040 */ 1041 resolves = 1; /* unless we know otherwise */ 1042 if (deps) { 1043 for (i = 0; i < deps->ls_length; i++) { 1044 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1045 if (mp->md_type != MDT_DEPEND) 1046 continue; 1047 modname = linker_reloc_ptr(lf, mp->md_cval); 1048 for (j = 0; j < deps->ls_length; j++) { 1049 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1050 if (nmp->md_type != MDT_VERSION) 1051 continue; 1052 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1053 if (strcmp(modname, nmodname) == 0) 1054 break; 1055 } 1056 if (j < deps->ls_length) /* it's a self reference */ 1057 continue; 1058 if (modlist_lookup(modname) == NULL) { 1059 /* ok, the module isn't here yet, we are not finished */ 1060 resolves = 0; 1061 } 1062 } 1063 } 1064 /* 1065 * OK, if we found our modules, we can link. So, "provide" the 1066 * modules inside and add it to the end of the link order list. 1067 */ 1068 if (resolves) { 1069 if (deps) { 1070 for (i = 0; i < deps->ls_length; i++) { 1071 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1072 if (mp->md_type != MDT_VERSION) 1073 continue; 1074 modname = linker_reloc_ptr(lf, mp->md_cval); 1075 if (modlist_lookup(modname) != NULL) { 1076 printf("module %s already present!\n", modname); 1077 linker_file_unload(lf); 1078 TAILQ_REMOVE(&loaded_files, lf, loaded); 1079 goto restart; /* we changed the tailq next ptr */ 1080 } 1081 mod = malloc(sizeof(struct modlist), M_LINKER, 1082 M_NOWAIT|M_ZERO); 1083 if (mod == NULL) 1084 panic("no memory for module list"); 1085 mod->container = lf; 1086 mod->name = modname; 1087 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1088 } 1089 } 1090 TAILQ_REMOVE(&loaded_files, lf, loaded); 1091 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1092 /* 1093 * Since we provided modules, we need to restart the sort so 1094 * that the previous files that depend on us have a chance. 1095 * Also, we've busted the tailq next pointer with the REMOVE. 1096 */ 1097 goto restart; 1098 } 1099 } 1100 1101 /* 1102 * At this point, we check to see what could not be resolved.. 1103 */ 1104 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1105 printf("KLD file %s is missing dependencies\n", lf->filename); 1106 linker_file_unload(lf); 1107 TAILQ_REMOVE(&loaded_files, lf, loaded); 1108 } 1109 1110 /* 1111 * We made it. Finish off the linking in the order we determined. 1112 */ 1113 TAILQ_FOREACH(lf, &depended_files, loaded) { 1114 if (linker_kernel_file) { 1115 linker_kernel_file->refs++; 1116 error = linker_file_add_dependancy(lf, linker_kernel_file); 1117 if (error) 1118 panic("cannot add dependency"); 1119 } 1120 lf->userrefs++; /* so we can (try to) kldunload it */ 1121 deps = (struct linker_set*) 1122 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1123 if (deps) { 1124 for (i = 0; i < deps->ls_length; i++) { 1125 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1126 if (mp->md_type != MDT_DEPEND) 1127 continue; 1128 modname = linker_reloc_ptr(lf, mp->md_cval); 1129 mod = modlist_lookup(modname); 1130 mod->container->refs++; 1131 error = linker_file_add_dependancy(lf, mod->container); 1132 if (error) 1133 panic("cannot add dependency"); 1134 } 1135 } 1136 1137 /* Now do relocation etc using the symbol search paths established by the dependencies */ 1138 error = LINKER_LINK_PRELOAD_FINISH(lf); 1139 if (error) { 1140 printf("KLD file %s - could not finalize loading\n", lf->filename); 1141 linker_file_unload(lf); 1142 continue; 1143 } 1144 1145 mcount = linker_file_register_modules(lf); 1146 sysinits = (struct linker_set*) 1147 linker_file_lookup_symbol(lf, "sysinit_set", 0); 1148 if (sysinits) 1149 sysinit_add((struct sysinit **)sysinits->ls_items); 1150 linker_file_register_sysctls(lf); 1151 lf->flags |= LINKER_FILE_LINKED; 1152 } 1153 /* woohoo! we made it! */ 1154 } 1155 1156 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1157 1158 /* 1159 * Search for a not-loaded module by name. 1160 * 1161 * Modules may be found in the following locations: 1162 * 1163 * - preloaded (result is just the module name) 1164 * - on disk (result is full path to module) 1165 * 1166 * If the module name is qualified in any way (contains path, etc.) 1167 * the we simply return a copy of it. 1168 * 1169 * The search path can be manipulated via sysctl. Note that we use the ';' 1170 * character as a separator to be consistent with the bootloader. 1171 */ 1172 1173 static char def_linker_path[] = "/boot/modules/;/modules/;/boot/kernel/"; 1174 static char linker_path[MAXPATHLEN] = ""; 1175 1176 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1177 sizeof(linker_path), "module load search path"); 1178 1179 TUNABLE_STR_DECL("module_path", def_linker_path, linker_path, 1180 sizeof(linker_path)); 1181 1182 static char *linker_ext_list[] = { 1183 ".ko", 1184 "", 1185 NULL 1186 }; 1187 1188 static char * 1189 linker_search_path(const char *name) 1190 { 1191 struct nameidata nd; 1192 struct proc *p = curproc; /* XXX */ 1193 char *cp, *ep, *result, **cpp; 1194 int error, extlen, len, flags; 1195 enum vtype type; 1196 1197 /* qualified at all? */ 1198 if (index(name, '/')) 1199 return(linker_strdup(name)); 1200 1201 extlen = 0; 1202 for (cpp = linker_ext_list; *cpp; cpp++) { 1203 len = strlen(*cpp); 1204 if (len > extlen) 1205 extlen = len; 1206 } 1207 extlen++; /* trailing '\0' */ 1208 1209 /* traverse the linker path */ 1210 cp = linker_path; 1211 len = strlen(name); 1212 for (;;) { 1213 1214 /* find the end of this component */ 1215 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) 1216 ; 1217 result = malloc((len + (ep - cp) + extlen + 1), M_LINKER, M_WAITOK); 1218 if (result == NULL) /* actually ENOMEM */ 1219 return(NULL); 1220 for (cpp = linker_ext_list; *cpp; cpp++) { 1221 strncpy(result, cp, ep - cp); 1222 strcpy(result + (ep - cp), "/"); 1223 strcat(result, name); 1224 strcat(result, *cpp); 1225 /* 1226 * Attempt to open the file, and return the path if we succeed 1227 * and it's a regular file. 1228 */ 1229 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p); 1230 flags = FREAD; 1231 error = vn_open(&nd, &flags, 0); 1232 if (error == 0) { 1233 NDFREE(&nd, NDF_ONLY_PNBUF); 1234 type = nd.ni_vp->v_type; 1235 VOP_UNLOCK(nd.ni_vp, 0, p); 1236 vn_close(nd.ni_vp, FREAD, p->p_ucred, p); 1237 if (type == VREG) 1238 return(result); 1239 } 1240 } 1241 free(result, M_LINKER); 1242 1243 if (*ep == 0) 1244 break; 1245 cp = ep + 1; 1246 } 1247 return(NULL); 1248 } 1249 1250 static const char * 1251 linker_basename(const char* path) 1252 { 1253 const char *filename; 1254 1255 filename = rindex(path, '/'); 1256 if (filename == NULL) 1257 return path; 1258 if (filename[1]) 1259 filename++; 1260 return filename; 1261 } 1262 1263 /* 1264 * Find a file which contains given module and load it, 1265 * if "parent" is not NULL, register a reference to it. 1266 */ 1267 static int 1268 linker_load_module(const char *modname, struct linker_file *parent) 1269 { 1270 linker_file_t lfdep; 1271 const char *filename; 1272 char *pathname; 1273 int error; 1274 1275 /* 1276 * There will be a system to look up or guess a file name from 1277 * a module name. 1278 * For now we just try to load a file with the same name. 1279 */ 1280 pathname = linker_search_path(modname); 1281 if (pathname == NULL) 1282 return ENOENT; 1283 1284 /* Can't load more than one file with the same basename */ 1285 filename = linker_basename(pathname); 1286 if (linker_find_file_by_name(filename)) { 1287 error = EEXIST; 1288 goto out; 1289 } 1290 1291 do { 1292 error = linker_load_file(pathname, &lfdep); 1293 if (error) 1294 break; 1295 if (parent) { 1296 error = linker_file_add_dependancy(parent, lfdep); 1297 if (error) 1298 break; 1299 } 1300 } while(0); 1301 out: 1302 if (pathname) 1303 free(pathname, M_LINKER); 1304 return error; 1305 } 1306 1307 /* 1308 * This routine is responsible for finding dependencies of userland 1309 * initiated kldload(2)'s of files. 1310 */ 1311 int 1312 linker_load_dependancies(linker_file_t lf) 1313 { 1314 linker_file_t lfdep; 1315 struct linker_set *deps; 1316 struct mod_metadata *mp, *nmp; 1317 modlist_t mod; 1318 char *modname, *nmodname; 1319 int i, j, error = 0; 1320 1321 /* 1322 * All files are dependant on /kernel. 1323 */ 1324 if (linker_kernel_file) { 1325 linker_kernel_file->refs++; 1326 error = linker_file_add_dependancy(lf, linker_kernel_file); 1327 if (error) 1328 return error; 1329 } 1330 1331 deps = (struct linker_set*) 1332 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1333 if (deps != NULL) { 1334 for (i = 0; i < deps->ls_length; i++) { 1335 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1336 if (mp->md_type != MDT_VERSION) 1337 continue; 1338 modname = linker_reloc_ptr(lf, mp->md_cval); 1339 if (modlist_lookup(modname) != NULL) { 1340 printf("module %s already present!\n", modname); 1341 return EEXIST; 1342 } 1343 } 1344 } 1345 if (deps != NULL) { 1346 for (i = 0; i < deps->ls_length; i++) { 1347 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1348 if (mp->md_type != MDT_DEPEND) 1349 continue; 1350 modname = linker_reloc_ptr(lf, mp->md_cval); 1351 nmodname = NULL; 1352 for (j = 0; j < deps->ls_length; j++) { 1353 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1354 if (nmp->md_type != MDT_VERSION) 1355 continue; 1356 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1357 if (strcmp(modname, nmodname) == 0) 1358 break; 1359 } 1360 if (j < deps->ls_length) /* early exit, it's a self reference */ 1361 continue; 1362 mod = modlist_lookup(modname); 1363 if (mod) { /* woohoo, it's loaded already */ 1364 lfdep = mod->container; 1365 lfdep->refs++; 1366 error = linker_file_add_dependancy(lf, lfdep); 1367 if (error) 1368 break; 1369 continue; 1370 } 1371 error = linker_load_module(modname, lf); 1372 if (error) { 1373 printf("KLD %s: depends on %s - not available\n", 1374 lf->filename, modname); 1375 break; 1376 } 1377 } 1378 1379 } 1380 if (error == 0 && deps) { 1381 for (i = 0; i < deps->ls_length; i++) { 1382 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1383 if (mp->md_type != MDT_VERSION) 1384 continue; 1385 modname = linker_reloc_ptr(lf, mp->md_cval); 1386 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); 1387 if (mod == NULL) 1388 panic("no memory for module list"); 1389 mod->container = lf; 1390 mod->name = modname; 1391 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1392 } 1393 } 1394 return error; 1395 } 1396