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