kern_linker.c revision 64143
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: head/sys/kern/kern_linker.c 64143 2000-08-02 21:08:53Z peter $ 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 51int kld_debug = 0; 52#endif 53 54static char *linker_search_path(const char *name); 55static const char *linker_basename(const char* path); 56 57MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 58 59linker_file_t linker_kernel_file; 60 61static struct lock lock; /* lock for the file list */ 62static linker_class_list_t classes; 63static linker_file_list_t linker_files; 64static int next_file_id = 1; 65 66/* XXX wrong name; we're looking at version provision tags here, not modules */ 67typedef TAILQ_HEAD(, modlist) modlisthead_t; 68struct modlist { 69 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 70 linker_file_t container; 71 const char *name; 72}; 73typedef struct modlist *modlist_t; 74static modlisthead_t found_modules; 75 76static char * 77linker_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 86static void 87linker_init(void* arg) 88{ 89 lockinit(&lock, PVM, "klink", 0, 0); 90 TAILQ_INIT(&classes); 91 TAILQ_INIT(&linker_files); 92} 93 94SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); 95 96int 97linker_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 104static void 105linker_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 154static void 155linker_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 204static void 205linker_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 222static void 223linker_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 240static int 241linker_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 289static void 290linker_init_kernel_modules(void) 291{ 292 linker_file_register_modules(linker_kernel_file); 293} 294 295SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0); 296 297int 298linker_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 /* Refuse to load modules if securelevel raised */ 305 if (securelevel > 0) 306 return EPERM; 307 308 lf = linker_find_file_by_name(filename); 309 if (lf) { 310 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename)); 311 *result = lf; 312 lf->refs++; 313 goto out; 314 } 315 316 lf = NULL; 317 foundfile = 0; 318 for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { 319 KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", 320 filename, lc->desc)); 321 error = LINKER_LOAD_FILE(lc, filename, &lf); 322 /* 323 * If we got something other than ENOENT, then it exists but we cannot 324 * load it for some other reason. 325 */ 326 if (error != ENOENT) 327 foundfile = 1; 328 if (lf) { 329 linker_file_register_modules(lf); 330 linker_file_register_sysctls(lf); 331 linker_file_sysinit(lf); 332 lf->flags |= LINKER_FILE_LINKED; 333 334 *result = lf; 335 error = 0; 336 goto out; 337 } 338 } 339 /* 340 * Less than ideal, but tells the user whether it failed to load or 341 * the module was not found. 342 */ 343 if (foundfile) 344 error = ENOEXEC; /* Format not recognised (or unloadable) */ 345 else 346 error = ENOENT; /* Nothing found */ 347 348out: 349 return error; 350} 351 352linker_file_t 353linker_find_file_by_name(const char* filename) 354{ 355 linker_file_t lf = 0; 356 char *koname; 357 358 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 359 if (koname == NULL) 360 goto out; 361 sprintf(koname, "%s.ko", filename); 362 363 lockmgr(&lock, LK_SHARED, 0, curproc); 364 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 365 if (!strcmp(lf->filename, koname)) 366 break; 367 if (!strcmp(lf->filename, filename)) 368 break; 369 } 370 lockmgr(&lock, LK_RELEASE, 0, curproc); 371 372out: 373 if (koname) 374 free(koname, M_LINKER); 375 return lf; 376} 377 378linker_file_t 379linker_find_file_by_id(int fileid) 380{ 381 linker_file_t lf = 0; 382 383 lockmgr(&lock, LK_SHARED, 0, curproc); 384 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) 385 if (lf->id == fileid) 386 break; 387 lockmgr(&lock, LK_RELEASE, 0, curproc); 388 389 return lf; 390} 391 392linker_file_t 393linker_make_file(const char* pathname, linker_class_t lc) 394{ 395 linker_file_t lf = 0; 396 const char *filename; 397 398 filename = linker_basename(pathname); 399 400 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 401 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 402 lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK); 403 if (!lf) 404 goto out; 405 406 lf->refs = 1; 407 lf->userrefs = 0; 408 lf->flags = 0; 409 lf->filename = linker_strdup(filename); 410 lf->id = next_file_id++; 411 lf->ndeps = 0; 412 lf->deps = NULL; 413 STAILQ_INIT(&lf->common); 414 TAILQ_INIT(&lf->modules); 415 416 TAILQ_INSERT_TAIL(&linker_files, lf, link); 417 418out: 419 lockmgr(&lock, LK_RELEASE, 0, curproc); 420 return lf; 421} 422 423int 424linker_file_unload(linker_file_t file) 425{ 426 module_t mod, next; 427 modlist_t ml, nextml; 428 struct common_symbol* cp; 429 int error = 0; 430 int i; 431 432 /* Refuse to unload modules if securelevel raised */ 433 if (securelevel > 0) 434 return EPERM; 435 436 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 437 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 438 if (file->refs == 1) { 439 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); 440 /* 441 * Inform any modules associated with this file. 442 */ 443 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 444 next = module_getfnext(mod); 445 446 /* 447 * Give the module a chance to veto the unload. 448 */ 449 if ((error = module_unload(mod)) != 0) { 450 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", 451 mod)); 452 lockmgr(&lock, LK_RELEASE, 0, curproc); 453 goto out; 454 } 455 456 module_release(mod); 457 } 458 } 459 460 file->refs--; 461 if (file->refs > 0) { 462 lockmgr(&lock, LK_RELEASE, 0, curproc); 463 goto out; 464 } 465 466 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 467 nextml = TAILQ_NEXT(ml, link); 468 if (ml->container == file) { 469 TAILQ_REMOVE(&found_modules, ml, link); 470 } 471 } 472 473 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ 474 if (file->flags & LINKER_FILE_LINKED) { 475 linker_file_sysuninit(file); 476 linker_file_unregister_sysctls(file); 477 } 478 479 TAILQ_REMOVE(&linker_files, file, link); 480 lockmgr(&lock, LK_RELEASE, 0, curproc); 481 482 if (file->deps) { 483 for (i = 0; i < file->ndeps; i++) 484 linker_file_unload(file->deps[i]); 485 free(file->deps, M_LINKER); 486 file->deps = NULL; 487 } 488 489 for (cp = STAILQ_FIRST(&file->common); cp; 490 cp = STAILQ_FIRST(&file->common)) { 491 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 492 free(cp, M_LINKER); 493 } 494 495 LINKER_UNLOAD(file); 496 if (file->filename) { 497 free(file->filename, M_LINKER); 498 file->filename = NULL; 499 } 500 kobj_delete((kobj_t) file, M_LINKER); 501 502out: 503 return error; 504} 505 506int 507linker_file_add_dependancy(linker_file_t file, linker_file_t dep) 508{ 509 linker_file_t* newdeps; 510 511 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*), 512 M_LINKER, M_WAITOK); 513 if (newdeps == NULL) 514 return ENOMEM; 515 bzero(newdeps, (file->ndeps + 1) * sizeof(linker_file_t*)); 516 517 if (file->deps) { 518 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); 519 free(file->deps, M_LINKER); 520 } 521 file->deps = newdeps; 522 file->deps[file->ndeps] = dep; 523 file->ndeps++; 524 525 return 0; 526} 527 528caddr_t 529linker_file_lookup_symbol(linker_file_t file, const char* name, int deps) 530{ 531 c_linker_sym_t sym; 532 linker_symval_t symval; 533 caddr_t address; 534 size_t common_size = 0; 535 int i; 536 537 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 538 file, name, deps)); 539 540 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 541 LINKER_SYMBOL_VALUES(file, sym, &symval); 542 if (symval.value == 0) 543 /* 544 * For commons, first look them up in the dependancies and 545 * only allocate space if not found there. 546 */ 547 common_size = symval.size; 548 else { 549 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); 550 return symval.value; 551 } 552 } 553 554 if (deps) { 555 for (i = 0; i < file->ndeps; i++) { 556 address = linker_file_lookup_symbol(file->deps[i], name, 0); 557 if (address) { 558 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address)); 559 return address; 560 } 561 } 562 } 563 564 if (common_size > 0) { 565 /* 566 * This is a common symbol which was not found in the 567 * dependancies. We maintain a simple common symbol table in 568 * the file object. 569 */ 570 struct common_symbol* cp; 571 572 for (cp = STAILQ_FIRST(&file->common); cp; 573 cp = STAILQ_NEXT(cp, link)) 574 if (!strcmp(cp->name, name)) { 575 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); 576 return cp->address; 577 } 578 579 /* 580 * Round the symbol size up to align. 581 */ 582 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 583 cp = malloc(sizeof(struct common_symbol) 584 + common_size 585 + strlen(name) + 1, 586 M_LINKER, M_WAITOK); 587 if (!cp) { 588 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 589 return 0; 590 } 591 bzero(cp, sizeof(struct common_symbol) + common_size + strlen(name)+ 1); 592 593 cp->address = (caddr_t) (cp + 1); 594 cp->name = cp->address + common_size; 595 strcpy(cp->name, name); 596 bzero(cp->address, common_size); 597 STAILQ_INSERT_TAIL(&file->common, cp, link); 598 599 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); 600 return cp->address; 601 } 602 603 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 604 return 0; 605} 606 607#ifdef DDB 608/* 609 * DDB Helpers. DDB has to look across multiple files with their own 610 * symbol tables and string tables. 611 * 612 * Note that we do not obey list locking protocols here. We really don't 613 * need DDB to hang because somebody's got the lock held. We'll take the 614 * chance that the files list is inconsistant instead. 615 */ 616 617int 618linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 619{ 620 linker_file_t lf; 621 622 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 623 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 624 return 0; 625 } 626 return ENOENT; 627} 628 629int 630linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 631{ 632 linker_file_t lf; 633 u_long off = (uintptr_t)value; 634 u_long diff, bestdiff; 635 c_linker_sym_t best; 636 c_linker_sym_t es; 637 638 best = 0; 639 bestdiff = off; 640 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 641 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 642 continue; 643 if (es != 0 && diff < bestdiff) { 644 best = es; 645 bestdiff = diff; 646 } 647 if (bestdiff == 0) 648 break; 649 } 650 if (best) { 651 *sym = best; 652 *diffp = bestdiff; 653 return 0; 654 } else { 655 *sym = 0; 656 *diffp = off; 657 return ENOENT; 658 } 659} 660 661int 662linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 663{ 664 linker_file_t lf; 665 666 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 667 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 668 return 0; 669 } 670 return ENOENT; 671} 672 673#endif 674 675/* 676 * Syscalls. 677 */ 678 679int 680kldload(struct proc* p, struct kldload_args* uap) 681{ 682 char* pathname, *realpath; 683 const char *filename; 684 linker_file_t lf; 685 int error = 0; 686 687 p->p_retval[0] = -1; 688 689 if (securelevel > 0) /* redundant, but that's OK */ 690 return EPERM; 691 692 if ((error = suser(p)) != 0) 693 return error; 694 695 realpath = NULL; 696 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 697 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 698 goto out; 699 700 realpath = linker_search_path(pathname); 701 if (realpath == NULL) { 702 error = ENOENT; 703 goto out; 704 } 705 /* Can't load more than one file with the same name */ 706 filename = linker_basename(realpath); 707 if (linker_find_file_by_name(filename)) { 708 error = EEXIST; 709 goto out; 710 } 711 712 if ((error = linker_load_file(realpath, &lf)) != 0) 713 goto out; 714 715 lf->userrefs++; 716 p->p_retval[0] = lf->id; 717 718out: 719 if (pathname) 720 free(pathname, M_TEMP); 721 if (realpath) 722 free(realpath, M_LINKER); 723 return error; 724} 725 726int 727kldunload(struct proc* p, struct kldunload_args* uap) 728{ 729 linker_file_t lf; 730 int error = 0; 731 732 if (securelevel > 0) /* redundant, but that's OK */ 733 return EPERM; 734 735 if ((error = suser(p)) != 0) 736 return error; 737 738 lf = linker_find_file_by_id(SCARG(uap, fileid)); 739 if (lf) { 740 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 741 if (lf->userrefs == 0) { 742 printf("kldunload: attempt to unload file that was loaded by the kernel\n"); 743 error = EBUSY; 744 goto out; 745 } 746 lf->userrefs--; 747 error = linker_file_unload(lf); 748 if (error) 749 lf->userrefs++; 750 } else 751 error = ENOENT; 752 753out: 754 return error; 755} 756 757int 758kldfind(struct proc* p, struct kldfind_args* uap) 759{ 760 char* pathname; 761 const char *filename; 762 linker_file_t lf; 763 int error = 0; 764 765 p->p_retval[0] = -1; 766 767 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 768 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 769 goto out; 770 771 filename = linker_basename(pathname); 772 773 lf = linker_find_file_by_name(filename); 774 if (lf) 775 p->p_retval[0] = lf->id; 776 else 777 error = ENOENT; 778 779out: 780 if (pathname) 781 free(pathname, M_TEMP); 782 return error; 783} 784 785int 786kldnext(struct proc* p, struct kldnext_args* uap) 787{ 788 linker_file_t lf; 789 int error = 0; 790 791 if (SCARG(uap, fileid) == 0) { 792 if (TAILQ_FIRST(&linker_files)) 793 p->p_retval[0] = TAILQ_FIRST(&linker_files)->id; 794 else 795 p->p_retval[0] = 0; 796 return 0; 797 } 798 799 lf = linker_find_file_by_id(SCARG(uap, fileid)); 800 if (lf) { 801 if (TAILQ_NEXT(lf, link)) 802 p->p_retval[0] = TAILQ_NEXT(lf, link)->id; 803 else 804 p->p_retval[0] = 0; 805 } else 806 error = ENOENT; 807 808 return error; 809} 810 811int 812kldstat(struct proc* p, struct kldstat_args* uap) 813{ 814 linker_file_t lf; 815 int error = 0; 816 int version; 817 struct kld_file_stat* stat; 818 int namelen; 819 820 lf = linker_find_file_by_id(SCARG(uap, fileid)); 821 if (!lf) { 822 error = ENOENT; 823 goto out; 824 } 825 826 stat = SCARG(uap, stat); 827 828 /* 829 * Check the version of the user's structure. 830 */ 831 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 832 goto out; 833 if (version != sizeof(struct kld_file_stat)) { 834 error = EINVAL; 835 goto out; 836 } 837 838 namelen = strlen(lf->filename) + 1; 839 if (namelen > MAXPATHLEN) 840 namelen = MAXPATHLEN; 841 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 842 goto out; 843 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 844 goto out; 845 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 846 goto out; 847 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0) 848 goto out; 849 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 850 goto out; 851 852 p->p_retval[0] = 0; 853 854out: 855 return error; 856} 857 858int 859kldfirstmod(struct proc* p, struct kldfirstmod_args* uap) 860{ 861 linker_file_t lf; 862 int error = 0; 863 864 lf = linker_find_file_by_id(SCARG(uap, fileid)); 865 if (lf) { 866 if (TAILQ_FIRST(&lf->modules)) 867 p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules)); 868 else 869 p->p_retval[0] = 0; 870 } else 871 error = ENOENT; 872 873 return error; 874} 875 876int 877kldsym(struct proc *p, struct kldsym_args *uap) 878{ 879 char *symstr = NULL; 880 c_linker_sym_t sym; 881 linker_symval_t symval; 882 linker_file_t lf; 883 struct kld_sym_lookup lookup; 884 int error = 0; 885 886 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0) 887 goto out; 888 if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) { 889 error = EINVAL; 890 goto out; 891 } 892 893 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 894 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 895 goto out; 896 897 if (SCARG(uap, fileid) != 0) { 898 lf = linker_find_file_by_id(SCARG(uap, fileid)); 899 if (lf == NULL) { 900 error = ENOENT; 901 goto out; 902 } 903 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 904 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 905 lookup.symvalue = (uintptr_t)symval.value; 906 lookup.symsize = symval.size; 907 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 908 } else 909 error = ENOENT; 910 } else { 911 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 912 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 913 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 914 lookup.symvalue = (uintptr_t)symval.value; 915 lookup.symsize = symval.size; 916 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 917 break; 918 } 919 } 920 if (!lf) 921 error = ENOENT; 922 } 923out: 924 if (symstr) 925 free(symstr, M_TEMP); 926 return error; 927} 928 929/* 930 * Preloaded module support 931 */ 932 933static modlist_t 934modlist_lookup(const char *name) 935{ 936 modlist_t mod; 937 938 for (mod = TAILQ_FIRST(&found_modules); mod; mod = TAILQ_NEXT(mod, link)) { 939 if (!strcmp(mod->name, name)) 940 return mod; 941 } 942 return NULL; 943} 944 945/* 946 * This routine is cheap and nasty but will work for data pointers. 947 */ 948static void * 949linker_reloc_ptr(linker_file_t lf, void *offset) 950{ 951 return lf->address + (uintptr_t)offset; 952} 953 954static void 955linker_preload(void* arg) 956{ 957 caddr_t modptr; 958 char *modname, *nmodname; 959 char *modtype; 960 linker_file_t lf; 961 linker_class_t lc; 962 int error, mcount; 963 struct linker_set *sysinits; 964 linker_file_list_t loaded_files; 965 linker_file_list_t depended_files; 966 struct linker_set *deps; 967 struct mod_metadata *mp, *nmp; 968 int i, j; 969 int resolves; 970 modlist_t mod; 971 972 TAILQ_INIT(&loaded_files); 973 TAILQ_INIT(&depended_files); 974 TAILQ_INIT(&found_modules); 975 error = 0; 976 977 modptr = NULL; 978 while ((modptr = preload_search_next_name(modptr)) != NULL) { 979 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 980 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 981 if (modname == NULL) { 982 printf("Preloaded module at %p does not have a name!\n", modptr); 983 continue; 984 } 985 if (modtype == NULL) { 986 printf("Preloaded module at %p does not have a type!\n", modptr); 987 continue; 988 } 989 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr); 990 lf = NULL; 991 for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { 992 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 993 if (error) { 994 lf = NULL; 995 break; 996 } 997 } 998 if (lf) 999 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1000 } 1001 1002 /* 1003 * First get a list of stuff in the kernel. 1004 */ 1005 deps = (struct linker_set*) 1006 linker_file_lookup_symbol(linker_kernel_file, MDT_SETNAME, 0); 1007 if (deps) { 1008 for (i = 0; i < deps->ls_length; i++) { 1009 mp = deps->ls_items[i]; 1010 if (mp->md_type != MDT_VERSION) 1011 continue; 1012 modname = mp->md_cval; 1013 if (modlist_lookup(modname) != NULL) { 1014 printf("module %s already present!\n", modname); 1015 /* XXX what can we do? this is a build error. :-( */ 1016 continue; 1017 } 1018 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT); 1019 if (mod == NULL) 1020 panic("no memory for module list"); 1021 bzero(mod, sizeof(*mod)); 1022 mod->container = linker_kernel_file; 1023 mod->name = modname; 1024 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1025 } 1026 } 1027 1028 /* 1029 * this is a once-off kinky bubble sort 1030 * resolve relocation dependency requirements 1031 */ 1032restart: 1033 for (lf = TAILQ_FIRST(&loaded_files); lf; lf = TAILQ_NEXT(lf, loaded)) { 1034 deps = (struct linker_set*) 1035 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1036 /* 1037 * First, look to see if we would successfully link with this stuff. 1038 */ 1039 resolves = 1; /* unless we know otherwise */ 1040 if (deps) { 1041 for (i = 0; i < deps->ls_length; i++) { 1042 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1043 if (mp->md_type != MDT_DEPEND) 1044 continue; 1045 modname = linker_reloc_ptr(lf, mp->md_cval); 1046 for (j = 0; j < deps->ls_length; j++) { 1047 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1048 if (nmp->md_type != MDT_VERSION) 1049 continue; 1050 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1051 if (strcmp(modname, nmodname) == 0) 1052 break; 1053 } 1054 if (j < deps->ls_length) /* it's a self reference */ 1055 continue; 1056 if (modlist_lookup(modname) == NULL) { 1057 /* ok, the module isn't here yet, we are not finished */ 1058 resolves = 0; 1059 } 1060 } 1061 } 1062 /* 1063 * OK, if we found our modules, we can link. So, "provide" the 1064 * modules inside and add it to the end of the link order list. 1065 */ 1066 if (resolves) { 1067 if (deps) { 1068 for (i = 0; i < deps->ls_length; i++) { 1069 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1070 if (mp->md_type != MDT_VERSION) 1071 continue; 1072 modname = linker_reloc_ptr(lf, mp->md_cval); 1073 if (modlist_lookup(modname) != NULL) { 1074 printf("module %s already present!\n", modname); 1075 linker_file_unload(lf); 1076 TAILQ_REMOVE(&loaded_files, lf, loaded); 1077 goto restart; /* we changed the tailq next ptr */ 1078 } 1079 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT); 1080 if (mod == NULL) 1081 panic("no memory for module list"); 1082 bzero(mod, sizeof(*mod)); 1083 mod->container = lf; 1084 mod->name = modname; 1085 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1086 } 1087 } 1088 TAILQ_REMOVE(&loaded_files, lf, loaded); 1089 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1090 /* 1091 * Since we provided modules, we need to restart the sort so 1092 * that the previous files that depend on us have a chance. 1093 * Also, we've busted the tailq next pointer with the REMOVE. 1094 */ 1095 goto restart; 1096 } 1097 } 1098 1099 /* 1100 * At this point, we check to see what could not be resolved.. 1101 */ 1102 for (lf = TAILQ_FIRST(&loaded_files); lf; lf = TAILQ_NEXT(lf, loaded)) { 1103 printf("KLD file %s is missing dependencies\n", lf->filename); 1104 linker_file_unload(lf); 1105 TAILQ_REMOVE(&loaded_files, lf, loaded); 1106 } 1107 1108 /* 1109 * We made it. Finish off the linking in the order we determined. 1110 */ 1111 for (lf = TAILQ_FIRST(&depended_files); lf; lf = TAILQ_NEXT(lf, loaded)) { 1112 if (linker_kernel_file) { 1113 linker_kernel_file->refs++; 1114 error = linker_file_add_dependancy(lf, linker_kernel_file); 1115 if (error) 1116 panic("cannot add dependency"); 1117 } 1118 lf->userrefs++; /* so we can (try to) kldunload it */ 1119 deps = (struct linker_set*) 1120 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1121 if (deps) { 1122 for (i = 0; i < deps->ls_length; i++) { 1123 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1124 if (mp->md_type != MDT_DEPEND) 1125 continue; 1126 modname = linker_reloc_ptr(lf, mp->md_cval); 1127 mod = modlist_lookup(modname); 1128 mod->container->refs++; 1129 error = linker_file_add_dependancy(lf, mod->container); 1130 if (error) 1131 panic("cannot add dependency"); 1132 } 1133 } 1134 1135 /* Now do relocation etc using the symbol search paths established by the dependencies */ 1136 error = LINKER_LINK_PRELOAD_FINISH(lf); 1137 if (error) { 1138 printf("KLD file %s - could not finalize loading\n", lf->filename); 1139 linker_file_unload(lf); 1140 continue; 1141 } 1142 1143 mcount = linker_file_register_modules(lf); 1144 sysinits = (struct linker_set*) 1145 linker_file_lookup_symbol(lf, "sysinit_set", 0); 1146 if (sysinits) 1147 sysinit_add((struct sysinit **)sysinits->ls_items); 1148 linker_file_register_sysctls(lf); 1149 lf->flags |= LINKER_FILE_LINKED; 1150 } 1151 /* woohoo! we made it! */ 1152} 1153 1154SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1155 1156/* 1157 * Search for a not-loaded module by name. 1158 * 1159 * Modules may be found in the following locations: 1160 * 1161 * - preloaded (result is just the module name) 1162 * - on disk (result is full path to module) 1163 * 1164 * If the module name is qualified in any way (contains path, etc.) 1165 * the we simply return a copy of it. 1166 * 1167 * The search path can be manipulated via sysctl. Note that we use the ';' 1168 * character as a separator to be consistent with the bootloader. 1169 */ 1170 1171static char linker_path[MAXPATHLEN] = "/;/boot/;/modules/"; 1172 1173SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1174 sizeof(linker_path), "module load search path"); 1175 1176static char *linker_ext_list[] = { 1177 ".ko", 1178 "", 1179 NULL 1180}; 1181 1182static char * 1183linker_search_path(const char *name) 1184{ 1185 struct nameidata nd; 1186 struct proc *p = curproc; /* XXX */ 1187 char *cp, *ep, *result, **cpp; 1188 int error, extlen, len, flags; 1189 enum vtype type; 1190 1191 /* qualified at all? */ 1192 if (index(name, '/')) 1193 return(linker_strdup(name)); 1194 1195 extlen = 0; 1196 for (cpp = linker_ext_list; *cpp; cpp++) { 1197 len = strlen(*cpp); 1198 if (len > extlen) 1199 extlen = len; 1200 } 1201 extlen++; /* trailing '\0' */ 1202 1203 /* traverse the linker path */ 1204 cp = linker_path; 1205 len = strlen(name); 1206 for (;;) { 1207 1208 /* find the end of this component */ 1209 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) 1210 ; 1211 result = malloc((len + (ep - cp) + extlen), M_LINKER, M_WAITOK); 1212 if (result == NULL) /* actually ENOMEM */ 1213 return(NULL); 1214 for (cpp = linker_ext_list; *cpp; cpp++) { 1215 strncpy(result, cp, ep - cp); 1216 strcpy(result + (ep - cp), name); 1217 strcat(result, *cpp); 1218 1219 /* 1220 * Attempt to open the file, and return the path if we succeed 1221 * and it's a regular file. 1222 */ 1223 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p); 1224 flags = FREAD; 1225 error = vn_open(&nd, &flags, 0); 1226 if (error == 0) { 1227 NDFREE(&nd, NDF_ONLY_PNBUF); 1228 type = nd.ni_vp->v_type; 1229 VOP_UNLOCK(nd.ni_vp, 0, p); 1230 vn_close(nd.ni_vp, FREAD, p->p_ucred, p); 1231 if (type == VREG) 1232 return(result); 1233 } 1234 } 1235 free(result, M_LINKER); 1236 1237 if (*ep == 0) 1238 break; 1239 cp = ep + 1; 1240 } 1241 return(NULL); 1242} 1243 1244static const char * 1245linker_basename(const char* path) 1246{ 1247 const char *filename; 1248 1249 filename = rindex(path, '/'); 1250 if (filename == NULL) 1251 return path; 1252 if (filename[1]) 1253 filename++; 1254 return filename; 1255} 1256 1257/* 1258 * Find a file which contains given module and load it, 1259 * if "parent" is not NULL, register a reference to it. 1260 */ 1261static int 1262linker_load_module(const char *modname, struct linker_file *parent) 1263{ 1264 linker_file_t lfdep; 1265 const char *filename; 1266 char *pathname; 1267 int error; 1268 1269 /* 1270 * There will be a system to look up or guess a file name from 1271 * a module name. 1272 * For now we just try to load a file with the same name. 1273 */ 1274 pathname = linker_search_path(modname); 1275 if (pathname == NULL) 1276 return ENOENT; 1277 1278 /* Can't load more than one file with the same basename */ 1279 filename = linker_basename(pathname); 1280 if (linker_find_file_by_name(filename)) { 1281 error = EEXIST; 1282 goto out; 1283 } 1284 1285 do { 1286 error = linker_load_file(pathname, &lfdep); 1287 if (error) 1288 break; 1289 if (parent) { 1290 error = linker_file_add_dependancy(parent, lfdep); 1291 if (error) 1292 break; 1293 } 1294 } while(0); 1295out: 1296 if (pathname) 1297 free(pathname, M_LINKER); 1298 return error; 1299} 1300 1301/* 1302 * This routine is responsible for finding dependencies of userland 1303 * initiated kldload(2)'s of files. 1304 */ 1305int 1306linker_load_dependancies(linker_file_t lf) 1307{ 1308 linker_file_t lfdep; 1309 struct linker_set *deps; 1310 struct mod_metadata *mp, *nmp; 1311 modlist_t mod; 1312 char *modname, *nmodname; 1313 int i, j, error = 0; 1314 1315 /* 1316 * All files are dependant on /kernel. 1317 */ 1318 if (linker_kernel_file) { 1319 linker_kernel_file->refs++; 1320 error = linker_file_add_dependancy(lf, linker_kernel_file); 1321 if (error) 1322 return error; 1323 } 1324 1325 deps = (struct linker_set*) 1326 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1327 if (deps != NULL) { 1328 for (i = 0; i < deps->ls_length; i++) { 1329 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1330 if (mp->md_type != MDT_VERSION) 1331 continue; 1332 modname = linker_reloc_ptr(lf, mp->md_cval); 1333 if (modlist_lookup(modname) != NULL) { 1334 printf("module %s already present!\n", modname); 1335 return EEXIST; 1336 } 1337 } 1338 } 1339 if (deps != NULL) { 1340 for (i = 0; i < deps->ls_length; i++) { 1341 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1342 if (mp->md_type != MDT_DEPEND) 1343 continue; 1344 modname = linker_reloc_ptr(lf, mp->md_cval); 1345 nmodname = NULL; 1346 for (j = 0; j < deps->ls_length; j++) { 1347 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1348 if (nmp->md_type != MDT_VERSION) 1349 continue; 1350 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1351 if (strcmp(modname, nmodname) == 0) 1352 break; 1353 } 1354 if (j < deps->ls_length) /* early exit, it's a self reference */ 1355 continue; 1356 mod = modlist_lookup(modname); 1357 if (mod) { /* woohoo, it's loaded already */ 1358 lfdep = mod->container; 1359 lfdep->refs++; 1360 error = linker_file_add_dependancy(lf, lfdep); 1361 if (error) 1362 break; 1363 continue; 1364 } 1365 error = linker_load_module(modname, lf); 1366 if (error) { 1367 printf("KLD %s: depends on %s - not available\n", 1368 lf->filename, modname); 1369 break; 1370 } 1371 } 1372 1373 } 1374 if (error == 0 && deps) { 1375 for (i = 0; i < deps->ls_length; i++) { 1376 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1377 if (mp->md_type != MDT_VERSION) 1378 continue; 1379 modname = linker_reloc_ptr(lf, mp->md_cval); 1380 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT); 1381 if (mod == NULL) 1382 panic("no memory for module list"); 1383 bzero(mod, sizeof(*mod)); 1384 mod->container = lf; 1385 mod->name = modname; 1386 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1387 } 1388 } 1389 return error; 1390} 1391