kern_linker.c revision 74641
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 74641 2001-03-22 07:55:33Z bp $ 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 240extern struct linker_set modmetadata_set; 241 242static int 243linker_file_register_modules(linker_file_t lf) 244{ 245 int error; 246 struct linker_set *modules; 247 struct mod_metadata **mdpp; 248 const moduledata_t *moddata; 249 250 KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n", 251 lf->filename)); 252 253 modules = (struct linker_set*) 254 linker_file_lookup_symbol(lf, "modmetadata_set", 0); 255 256 if (!modules && lf == linker_kernel_file) 257 modules = &modmetadata_set; 258 259 if (modules == NULL) 260 return 0; 261 for (mdpp = (struct mod_metadata**)modules->ls_items; *mdpp; mdpp++) { 262 if ((*mdpp)->md_type != MDT_MODULE) 263 continue; 264 moddata = (*mdpp)->md_data; 265 KLD_DPF(FILE, ("Registering module %s in %s\n", 266 moddata->name, lf->filename)); 267 if (module_lookupbyname(moddata->name) != NULL) { 268 printf("Warning: module %s already exists\n", moddata->name); 269 continue; /* or return a error ? */ 270 } 271 error = module_register(moddata, lf); 272 if (error) 273 printf("Module %s failed to register: %d\n", moddata->name, error); 274 } 275 return 0; 276} 277 278static void 279linker_init_kernel_modules(void) 280{ 281 linker_file_register_modules(linker_kernel_file); 282} 283 284SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0); 285 286int 287linker_load_file(const char* filename, linker_file_t* result) 288{ 289 linker_class_t lc; 290 linker_file_t lf; 291 int foundfile, error = 0; 292 293 /* Refuse to load modules if securelevel raised */ 294 if (securelevel > 0) 295 return EPERM; 296 297 lf = linker_find_file_by_name(filename); 298 if (lf) { 299 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename)); 300 *result = lf; 301 lf->refs++; 302 goto out; 303 } 304 305 lf = NULL; 306 foundfile = 0; 307 TAILQ_FOREACH(lc, &classes, link) { 308 KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", 309 filename, lc->desc)); 310 error = LINKER_LOAD_FILE(lc, filename, &lf); 311 /* 312 * If we got something other than ENOENT, then it exists but we cannot 313 * load it for some other reason. 314 */ 315 if (error != ENOENT) 316 foundfile = 1; 317 if (lf) { 318 linker_file_register_modules(lf); 319 linker_file_register_sysctls(lf); 320 linker_file_sysinit(lf); 321 lf->flags |= LINKER_FILE_LINKED; 322 323 *result = lf; 324 error = 0; 325 goto out; 326 } 327 } 328 /* 329 * Less than ideal, but tells the user whether it failed to load or 330 * the module was not found. 331 */ 332 if (foundfile) 333 error = ENOEXEC; /* Format not recognised (or unloadable) */ 334 else 335 error = ENOENT; /* Nothing found */ 336 337out: 338 return error; 339} 340 341linker_file_t 342linker_find_file_by_name(const char* filename) 343{ 344 linker_file_t lf = 0; 345 char *koname; 346 347 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 348 if (koname == NULL) 349 goto out; 350 sprintf(koname, "%s.ko", filename); 351 352 lockmgr(&lock, LK_SHARED, 0, curproc); 353 TAILQ_FOREACH(lf, &linker_files, link) { 354 if (!strcmp(lf->filename, koname)) 355 break; 356 if (!strcmp(lf->filename, filename)) 357 break; 358 } 359 lockmgr(&lock, LK_RELEASE, 0, curproc); 360 361out: 362 if (koname) 363 free(koname, M_LINKER); 364 return lf; 365} 366 367linker_file_t 368linker_find_file_by_id(int fileid) 369{ 370 linker_file_t lf = 0; 371 372 lockmgr(&lock, LK_SHARED, 0, curproc); 373 TAILQ_FOREACH(lf, &linker_files, link) 374 if (lf->id == fileid) 375 break; 376 lockmgr(&lock, LK_RELEASE, 0, curproc); 377 378 return lf; 379} 380 381linker_file_t 382linker_make_file(const char* pathname, linker_class_t lc) 383{ 384 linker_file_t lf = 0; 385 const char *filename; 386 387 filename = linker_basename(pathname); 388 389 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 390 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 391 lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK); 392 if (!lf) 393 goto out; 394 395 lf->refs = 1; 396 lf->userrefs = 0; 397 lf->flags = 0; 398 lf->filename = linker_strdup(filename); 399 lf->id = next_file_id++; 400 lf->ndeps = 0; 401 lf->deps = NULL; 402 STAILQ_INIT(&lf->common); 403 TAILQ_INIT(&lf->modules); 404 405 TAILQ_INSERT_TAIL(&linker_files, lf, link); 406 407out: 408 lockmgr(&lock, LK_RELEASE, 0, curproc); 409 return lf; 410} 411 412int 413linker_file_unload(linker_file_t file) 414{ 415 module_t mod, next; 416 modlist_t ml, nextml; 417 struct common_symbol* cp; 418 int error = 0; 419 int i; 420 421 /* Refuse to unload modules if securelevel raised */ 422 if (securelevel > 0) 423 return EPERM; 424 425 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 426 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 427 if (file->refs == 1) { 428 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); 429 /* 430 * Inform any modules associated with this file. 431 */ 432 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 433 next = module_getfnext(mod); 434 435 /* 436 * Give the module a chance to veto the unload. 437 */ 438 if ((error = module_unload(mod)) != 0) { 439 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", 440 mod)); 441 lockmgr(&lock, LK_RELEASE, 0, curproc); 442 goto out; 443 } 444 445 module_release(mod); 446 } 447 } 448 449 file->refs--; 450 if (file->refs > 0) { 451 lockmgr(&lock, LK_RELEASE, 0, curproc); 452 goto out; 453 } 454 455 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 456 nextml = TAILQ_NEXT(ml, link); 457 if (ml->container == file) { 458 TAILQ_REMOVE(&found_modules, ml, link); 459 } 460 } 461 462 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ 463 if (file->flags & LINKER_FILE_LINKED) { 464 linker_file_sysuninit(file); 465 linker_file_unregister_sysctls(file); 466 } 467 468 TAILQ_REMOVE(&linker_files, file, link); 469 lockmgr(&lock, LK_RELEASE, 0, curproc); 470 471 if (file->deps) { 472 for (i = 0; i < file->ndeps; i++) 473 linker_file_unload(file->deps[i]); 474 free(file->deps, M_LINKER); 475 file->deps = NULL; 476 } 477 478 for (cp = STAILQ_FIRST(&file->common); cp; 479 cp = STAILQ_FIRST(&file->common)) { 480 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 481 free(cp, M_LINKER); 482 } 483 484 LINKER_UNLOAD(file); 485 if (file->filename) { 486 free(file->filename, M_LINKER); 487 file->filename = NULL; 488 } 489 kobj_delete((kobj_t) file, M_LINKER); 490 491out: 492 return error; 493} 494 495int 496linker_file_add_dependancy(linker_file_t file, linker_file_t dep) 497{ 498 linker_file_t* newdeps; 499 500 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*), 501 M_LINKER, M_WAITOK | M_ZERO); 502 if (newdeps == NULL) 503 return ENOMEM; 504 505 if (file->deps) { 506 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); 507 free(file->deps, M_LINKER); 508 } 509 file->deps = newdeps; 510 file->deps[file->ndeps] = dep; 511 file->ndeps++; 512 513 return 0; 514} 515 516caddr_t 517linker_file_lookup_symbol(linker_file_t file, const char* name, int deps) 518{ 519 c_linker_sym_t sym; 520 linker_symval_t symval; 521 caddr_t address; 522 size_t common_size = 0; 523 int i; 524 525 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 526 file, name, deps)); 527 528 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 529 LINKER_SYMBOL_VALUES(file, sym, &symval); 530 if (symval.value == 0) 531 /* 532 * For commons, first look them up in the dependancies and 533 * only allocate space if not found there. 534 */ 535 common_size = symval.size; 536 else { 537 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); 538 return symval.value; 539 } 540 } 541 542 if (deps) { 543 for (i = 0; i < file->ndeps; i++) { 544 address = linker_file_lookup_symbol(file->deps[i], name, 0); 545 if (address) { 546 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address)); 547 return address; 548 } 549 } 550 } 551 552 if (common_size > 0) { 553 /* 554 * This is a common symbol which was not found in the 555 * dependancies. We maintain a simple common symbol table in 556 * the file object. 557 */ 558 struct common_symbol* cp; 559 560 STAILQ_FOREACH(cp, &file->common, link) 561 if (!strcmp(cp->name, name)) { 562 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); 563 return cp->address; 564 } 565 566 /* 567 * Round the symbol size up to align. 568 */ 569 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 570 cp = malloc(sizeof(struct common_symbol) 571 + common_size 572 + strlen(name) + 1, 573 M_LINKER, M_WAITOK | M_ZERO); 574 if (!cp) { 575 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 576 return 0; 577 } 578 579 cp->address = (caddr_t) (cp + 1); 580 cp->name = cp->address + common_size; 581 strcpy(cp->name, name); 582 bzero(cp->address, common_size); 583 STAILQ_INSERT_TAIL(&file->common, cp, link); 584 585 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); 586 return cp->address; 587 } 588 589 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 590 return 0; 591} 592 593#ifdef DDB 594/* 595 * DDB Helpers. DDB has to look across multiple files with their own 596 * symbol tables and string tables. 597 * 598 * Note that we do not obey list locking protocols here. We really don't 599 * need DDB to hang because somebody's got the lock held. We'll take the 600 * chance that the files list is inconsistant instead. 601 */ 602 603int 604linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 605{ 606 linker_file_t lf; 607 608 TAILQ_FOREACH(lf, &linker_files, link) { 609 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 610 return 0; 611 } 612 return ENOENT; 613} 614 615int 616linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 617{ 618 linker_file_t lf; 619 u_long off = (uintptr_t)value; 620 u_long diff, bestdiff; 621 c_linker_sym_t best; 622 c_linker_sym_t es; 623 624 best = 0; 625 bestdiff = off; 626 TAILQ_FOREACH(lf, &linker_files, link) { 627 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 628 continue; 629 if (es != 0 && diff < bestdiff) { 630 best = es; 631 bestdiff = diff; 632 } 633 if (bestdiff == 0) 634 break; 635 } 636 if (best) { 637 *sym = best; 638 *diffp = bestdiff; 639 return 0; 640 } else { 641 *sym = 0; 642 *diffp = off; 643 return ENOENT; 644 } 645} 646 647int 648linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 649{ 650 linker_file_t lf; 651 652 TAILQ_FOREACH(lf, &linker_files, link) { 653 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 654 return 0; 655 } 656 return ENOENT; 657} 658 659#endif 660 661/* 662 * Syscalls. 663 */ 664 665int 666kldload(struct proc* p, struct kldload_args* uap) 667{ 668 char* pathname, *realpath; 669 const char *filename; 670 linker_file_t lf; 671 int error = 0; 672 673 p->p_retval[0] = -1; 674 675 if (securelevel > 0) /* redundant, but that's OK */ 676 return EPERM; 677 678 if ((error = suser(p)) != 0) 679 return error; 680 681 realpath = NULL; 682 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 683 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 684 goto out; 685 686 realpath = linker_search_path(pathname); 687 if (realpath == NULL) { 688 error = ENOENT; 689 goto out; 690 } 691 /* Can't load more than one file with the same name */ 692 filename = linker_basename(realpath); 693 if (linker_find_file_by_name(filename)) { 694 error = EEXIST; 695 goto out; 696 } 697 698 if ((error = linker_load_file(realpath, &lf)) != 0) 699 goto out; 700 701 lf->userrefs++; 702 p->p_retval[0] = lf->id; 703 704out: 705 if (pathname) 706 free(pathname, M_TEMP); 707 if (realpath) 708 free(realpath, M_LINKER); 709 return error; 710} 711 712int 713kldunload(struct proc* p, struct kldunload_args* uap) 714{ 715 linker_file_t lf; 716 int error = 0; 717 718 if (securelevel > 0) /* redundant, but that's OK */ 719 return EPERM; 720 721 if ((error = suser(p)) != 0) 722 return error; 723 724 lf = linker_find_file_by_id(SCARG(uap, fileid)); 725 if (lf) { 726 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 727 if (lf->userrefs == 0) { 728 printf("kldunload: attempt to unload file that was loaded by the kernel\n"); 729 error = EBUSY; 730 goto out; 731 } 732 lf->userrefs--; 733 error = linker_file_unload(lf); 734 if (error) 735 lf->userrefs++; 736 } else 737 error = ENOENT; 738 739out: 740 return error; 741} 742 743int 744kldfind(struct proc* p, struct kldfind_args* uap) 745{ 746 char* pathname; 747 const char *filename; 748 linker_file_t lf; 749 int error = 0; 750 751 p->p_retval[0] = -1; 752 753 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 754 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 755 goto out; 756 757 filename = linker_basename(pathname); 758 759 lf = linker_find_file_by_name(filename); 760 if (lf) 761 p->p_retval[0] = lf->id; 762 else 763 error = ENOENT; 764 765out: 766 if (pathname) 767 free(pathname, M_TEMP); 768 return error; 769} 770 771int 772kldnext(struct proc* p, struct kldnext_args* uap) 773{ 774 linker_file_t lf; 775 int error = 0; 776 777 if (SCARG(uap, fileid) == 0) { 778 if (TAILQ_FIRST(&linker_files)) 779 p->p_retval[0] = TAILQ_FIRST(&linker_files)->id; 780 else 781 p->p_retval[0] = 0; 782 return 0; 783 } 784 785 lf = linker_find_file_by_id(SCARG(uap, fileid)); 786 if (lf) { 787 if (TAILQ_NEXT(lf, link)) 788 p->p_retval[0] = TAILQ_NEXT(lf, link)->id; 789 else 790 p->p_retval[0] = 0; 791 } else 792 error = ENOENT; 793 794 return error; 795} 796 797int 798kldstat(struct proc* p, struct kldstat_args* uap) 799{ 800 linker_file_t lf; 801 int error = 0; 802 int version; 803 struct kld_file_stat* stat; 804 int namelen; 805 806 lf = linker_find_file_by_id(SCARG(uap, fileid)); 807 if (!lf) { 808 error = ENOENT; 809 goto out; 810 } 811 812 stat = SCARG(uap, stat); 813 814 /* 815 * Check the version of the user's structure. 816 */ 817 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 818 goto out; 819 if (version != sizeof(struct kld_file_stat)) { 820 error = EINVAL; 821 goto out; 822 } 823 824 namelen = strlen(lf->filename) + 1; 825 if (namelen > MAXPATHLEN) 826 namelen = MAXPATHLEN; 827 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 828 goto out; 829 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 830 goto out; 831 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 832 goto out; 833 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0) 834 goto out; 835 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 836 goto out; 837 838 p->p_retval[0] = 0; 839 840out: 841 return error; 842} 843 844int 845kldfirstmod(struct proc* p, struct kldfirstmod_args* uap) 846{ 847 linker_file_t lf; 848 int error = 0; 849 850 lf = linker_find_file_by_id(SCARG(uap, fileid)); 851 if (lf) { 852 if (TAILQ_FIRST(&lf->modules)) 853 p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules)); 854 else 855 p->p_retval[0] = 0; 856 } else 857 error = ENOENT; 858 859 return error; 860} 861 862int 863kldsym(struct proc *p, struct kldsym_args *uap) 864{ 865 char *symstr = NULL; 866 c_linker_sym_t sym; 867 linker_symval_t symval; 868 linker_file_t lf; 869 struct kld_sym_lookup lookup; 870 int error = 0; 871 872 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0) 873 goto out; 874 if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) { 875 error = EINVAL; 876 goto out; 877 } 878 879 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 880 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 881 goto out; 882 883 if (SCARG(uap, fileid) != 0) { 884 lf = linker_find_file_by_id(SCARG(uap, fileid)); 885 if (lf == NULL) { 886 error = ENOENT; 887 goto out; 888 } 889 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 890 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 891 lookup.symvalue = (uintptr_t)symval.value; 892 lookup.symsize = symval.size; 893 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 894 } else 895 error = ENOENT; 896 } else { 897 TAILQ_FOREACH(lf, &linker_files, link) { 898 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 899 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 900 lookup.symvalue = (uintptr_t)symval.value; 901 lookup.symsize = symval.size; 902 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 903 break; 904 } 905 } 906 if (!lf) 907 error = ENOENT; 908 } 909out: 910 if (symstr) 911 free(symstr, M_TEMP); 912 return error; 913} 914 915/* 916 * Preloaded module support 917 */ 918 919static modlist_t 920modlist_lookup(const char *name) 921{ 922 modlist_t mod; 923 924 TAILQ_FOREACH(mod, &found_modules, link) { 925 if (!strcmp(mod->name, name)) 926 return mod; 927 } 928 return NULL; 929} 930 931/* 932 * This routine is cheap and nasty but will work for data pointers. 933 */ 934static void * 935linker_reloc_ptr(linker_file_t lf, void *offset) 936{ 937 return lf->address + (uintptr_t)offset; 938} 939 940static void 941linker_preload(void* arg) 942{ 943 caddr_t modptr; 944 char *modname, *nmodname; 945 char *modtype; 946 linker_file_t lf; 947 linker_class_t lc; 948 int error; 949 struct linker_set *sysinits; 950 linker_file_list_t loaded_files; 951 linker_file_list_t depended_files; 952 struct linker_set *deps; 953 struct mod_metadata *mp, *nmp; 954 int i, j; 955 int resolves; 956 modlist_t mod; 957 958 TAILQ_INIT(&loaded_files); 959 TAILQ_INIT(&depended_files); 960 TAILQ_INIT(&found_modules); 961 error = 0; 962 963 modptr = NULL; 964 while ((modptr = preload_search_next_name(modptr)) != NULL) { 965 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 966 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 967 if (modname == NULL) { 968 printf("Preloaded module at %p does not have a name!\n", modptr); 969 continue; 970 } 971 if (modtype == NULL) { 972 printf("Preloaded module at %p does not have a type!\n", modptr); 973 continue; 974 } 975 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr); 976 lf = NULL; 977 TAILQ_FOREACH(lc, &classes, link) { 978 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 979 if (error) { 980 lf = NULL; 981 break; 982 } 983 } 984 if (lf) 985 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 986 } 987 988 /* 989 * First get a list of stuff in the kernel. 990 */ 991 deps = (struct linker_set*) 992 linker_file_lookup_symbol(linker_kernel_file, MDT_SETNAME, 0); 993 if (deps) { 994 for (i = 0; i < deps->ls_length; i++) { 995 mp = deps->ls_items[i]; 996 if (mp->md_type != MDT_VERSION) 997 continue; 998 modname = mp->md_cval; 999 if (modlist_lookup(modname) != NULL) { 1000 printf("module %s already present!\n", modname); 1001 /* XXX what can we do? this is a build error. :-( */ 1002 continue; 1003 } 1004 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); 1005 if (mod == NULL) 1006 panic("no memory for module list"); 1007 mod->container = linker_kernel_file; 1008 mod->name = modname; 1009 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1010 } 1011 } 1012 1013 /* 1014 * this is a once-off kinky bubble sort 1015 * resolve relocation dependency requirements 1016 */ 1017restart: 1018 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1019 deps = (struct linker_set*) 1020 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1021 /* 1022 * First, look to see if we would successfully link with this stuff. 1023 */ 1024 resolves = 1; /* unless we know otherwise */ 1025 if (deps) { 1026 for (i = 0; i < deps->ls_length; i++) { 1027 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1028 if (mp->md_type != MDT_DEPEND) 1029 continue; 1030 modname = linker_reloc_ptr(lf, mp->md_cval); 1031 for (j = 0; j < deps->ls_length; j++) { 1032 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1033 if (nmp->md_type != MDT_VERSION) 1034 continue; 1035 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1036 if (strcmp(modname, nmodname) == 0) 1037 break; 1038 } 1039 if (j < deps->ls_length) /* it's a self reference */ 1040 continue; 1041 if (modlist_lookup(modname) == NULL) { 1042 /* ok, the module isn't here yet, we are not finished */ 1043 resolves = 0; 1044 } 1045 } 1046 } 1047 /* 1048 * OK, if we found our modules, we can link. So, "provide" the 1049 * modules inside and add it to the end of the link order list. 1050 */ 1051 if (resolves) { 1052 if (deps) { 1053 for (i = 0; i < deps->ls_length; i++) { 1054 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1055 if (mp->md_type != MDT_VERSION) 1056 continue; 1057 modname = linker_reloc_ptr(lf, mp->md_cval); 1058 if (modlist_lookup(modname) != NULL) { 1059 printf("module %s already present!\n", modname); 1060 linker_file_unload(lf); 1061 TAILQ_REMOVE(&loaded_files, lf, loaded); 1062 goto restart; /* we changed the tailq next ptr */ 1063 } 1064 mod = malloc(sizeof(struct modlist), M_LINKER, 1065 M_NOWAIT|M_ZERO); 1066 if (mod == NULL) 1067 panic("no memory for module list"); 1068 mod->container = lf; 1069 mod->name = modname; 1070 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1071 } 1072 } 1073 TAILQ_REMOVE(&loaded_files, lf, loaded); 1074 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1075 /* 1076 * Since we provided modules, we need to restart the sort so 1077 * that the previous files that depend on us have a chance. 1078 * Also, we've busted the tailq next pointer with the REMOVE. 1079 */ 1080 goto restart; 1081 } 1082 } 1083 1084 /* 1085 * At this point, we check to see what could not be resolved.. 1086 */ 1087 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1088 printf("KLD file %s is missing dependencies\n", lf->filename); 1089 linker_file_unload(lf); 1090 TAILQ_REMOVE(&loaded_files, lf, loaded); 1091 } 1092 1093 /* 1094 * We made it. Finish off the linking in the order we determined. 1095 */ 1096 TAILQ_FOREACH(lf, &depended_files, loaded) { 1097 if (linker_kernel_file) { 1098 linker_kernel_file->refs++; 1099 error = linker_file_add_dependancy(lf, linker_kernel_file); 1100 if (error) 1101 panic("cannot add dependency"); 1102 } 1103 lf->userrefs++; /* so we can (try to) kldunload it */ 1104 deps = (struct linker_set*) 1105 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1106 if (deps) { 1107 for (i = 0; i < deps->ls_length; i++) { 1108 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1109 if (mp->md_type != MDT_DEPEND) 1110 continue; 1111 modname = linker_reloc_ptr(lf, mp->md_cval); 1112 mod = modlist_lookup(modname); 1113 mod->container->refs++; 1114 error = linker_file_add_dependancy(lf, mod->container); 1115 if (error) 1116 panic("cannot add dependency"); 1117 } 1118 } 1119 1120 /* Now do relocation etc using the symbol search paths established by the dependencies */ 1121 error = LINKER_LINK_PRELOAD_FINISH(lf); 1122 if (error) { 1123 printf("KLD file %s - could not finalize loading\n", lf->filename); 1124 linker_file_unload(lf); 1125 continue; 1126 } 1127 1128 linker_file_register_modules(lf); 1129 sysinits = (struct linker_set*) 1130 linker_file_lookup_symbol(lf, "sysinit_set", 0); 1131 if (sysinits) 1132 sysinit_add((struct sysinit **)sysinits->ls_items); 1133 linker_file_register_sysctls(lf); 1134 lf->flags |= LINKER_FILE_LINKED; 1135 } 1136 /* woohoo! we made it! */ 1137} 1138 1139SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1140 1141/* 1142 * Search for a not-loaded module by name. 1143 * 1144 * Modules may be found in the following locations: 1145 * 1146 * - preloaded (result is just the module name) 1147 * - on disk (result is full path to module) 1148 * 1149 * If the module name is qualified in any way (contains path, etc.) 1150 * the we simply return a copy of it. 1151 * 1152 * The search path can be manipulated via sysctl. Note that we use the ';' 1153 * character as a separator to be consistent with the bootloader. 1154 */ 1155 1156static char def_linker_path[] = "/boot/modules/;/modules/;/boot/kernel/"; 1157static char linker_path[MAXPATHLEN] = ""; 1158 1159SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1160 sizeof(linker_path), "module load search path"); 1161 1162TUNABLE_STR_DECL("module_path", def_linker_path, linker_path, 1163 sizeof(linker_path)); 1164 1165static char *linker_ext_list[] = { 1166 ".ko", 1167 "", 1168 NULL 1169}; 1170 1171static char * 1172linker_search_path(const char *name) 1173{ 1174 struct nameidata nd; 1175 struct proc *p = curproc; /* XXX */ 1176 char *cp, *ep, *result, **cpp; 1177 int error, extlen, len, flags; 1178 enum vtype type; 1179 1180 /* qualified at all? */ 1181 if (index(name, '/')) 1182 return(linker_strdup(name)); 1183 1184 extlen = 0; 1185 for (cpp = linker_ext_list; *cpp; cpp++) { 1186 len = strlen(*cpp); 1187 if (len > extlen) 1188 extlen = len; 1189 } 1190 extlen++; /* trailing '\0' */ 1191 1192 /* traverse the linker path */ 1193 cp = linker_path; 1194 len = strlen(name); 1195 for (;;) { 1196 1197 /* find the end of this component */ 1198 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) 1199 ; 1200 result = malloc((len + (ep - cp) + extlen + 1), M_LINKER, M_WAITOK); 1201 if (result == NULL) /* actually ENOMEM */ 1202 return(NULL); 1203 for (cpp = linker_ext_list; *cpp; cpp++) { 1204 strncpy(result, cp, ep - cp); 1205 strcpy(result + (ep - cp), "/"); 1206 strcat(result, name); 1207 strcat(result, *cpp); 1208 /* 1209 * Attempt to open the file, and return the path if we succeed 1210 * and it's a regular file. 1211 */ 1212 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p); 1213 flags = FREAD; 1214 error = vn_open(&nd, &flags, 0); 1215 if (error == 0) { 1216 NDFREE(&nd, NDF_ONLY_PNBUF); 1217 type = nd.ni_vp->v_type; 1218 VOP_UNLOCK(nd.ni_vp, 0, p); 1219 vn_close(nd.ni_vp, FREAD, p->p_ucred, p); 1220 if (type == VREG) 1221 return(result); 1222 } 1223 } 1224 free(result, M_LINKER); 1225 1226 if (*ep == 0) 1227 break; 1228 cp = ep + 1; 1229 } 1230 return(NULL); 1231} 1232 1233static const char * 1234linker_basename(const char* path) 1235{ 1236 const char *filename; 1237 1238 filename = rindex(path, '/'); 1239 if (filename == NULL) 1240 return path; 1241 if (filename[1]) 1242 filename++; 1243 return filename; 1244} 1245 1246/* 1247 * Find a file which contains given module and load it, 1248 * if "parent" is not NULL, register a reference to it. 1249 */ 1250static int 1251linker_load_module(const char *modname, struct linker_file *parent) 1252{ 1253 linker_file_t lfdep; 1254 const char *filename; 1255 char *pathname; 1256 int error; 1257 1258 /* 1259 * There will be a system to look up or guess a file name from 1260 * a module name. 1261 * For now we just try to load a file with the same name. 1262 */ 1263 pathname = linker_search_path(modname); 1264 if (pathname == NULL) 1265 return ENOENT; 1266 1267 /* Can't load more than one file with the same basename */ 1268 filename = linker_basename(pathname); 1269 if (linker_find_file_by_name(filename)) { 1270 error = EEXIST; 1271 goto out; 1272 } 1273 1274 do { 1275 error = linker_load_file(pathname, &lfdep); 1276 if (error) 1277 break; 1278 if (parent) { 1279 error = linker_file_add_dependancy(parent, lfdep); 1280 if (error) 1281 break; 1282 } 1283 } while(0); 1284out: 1285 if (pathname) 1286 free(pathname, M_LINKER); 1287 return error; 1288} 1289 1290/* 1291 * This routine is responsible for finding dependencies of userland 1292 * initiated kldload(2)'s of files. 1293 */ 1294int 1295linker_load_dependancies(linker_file_t lf) 1296{ 1297 linker_file_t lfdep; 1298 struct linker_set *deps; 1299 struct mod_metadata *mp, *nmp; 1300 modlist_t mod; 1301 char *modname, *nmodname; 1302 int i, j, error = 0; 1303 1304 /* 1305 * All files are dependant on /kernel. 1306 */ 1307 if (linker_kernel_file) { 1308 linker_kernel_file->refs++; 1309 error = linker_file_add_dependancy(lf, linker_kernel_file); 1310 if (error) 1311 return error; 1312 } 1313 1314 deps = (struct linker_set*) 1315 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1316 if (deps == NULL) 1317 return 0; 1318 for (i = 0; i < deps->ls_length; i++) { 1319 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1320 if (mp->md_type != MDT_VERSION) 1321 continue; 1322 modname = linker_reloc_ptr(lf, mp->md_cval); 1323 if (modlist_lookup(modname) != NULL) { 1324 printf("module %s already present!\n", modname); 1325 return EEXIST; 1326 } 1327 } 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_DEPEND) 1331 continue; 1332 modname = linker_reloc_ptr(lf, mp->md_cval); 1333 nmodname = NULL; 1334 for (j = 0; j < deps->ls_length; j++) { 1335 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1336 if (nmp->md_type != MDT_VERSION) 1337 continue; 1338 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1339 if (strcmp(modname, nmodname) == 0) 1340 break; 1341 } 1342 if (j < deps->ls_length) /* early exit, it's a self reference */ 1343 continue; 1344 mod = modlist_lookup(modname); 1345 if (mod) { /* woohoo, it's loaded already */ 1346 lfdep = mod->container; 1347 lfdep->refs++; 1348 error = linker_file_add_dependancy(lf, lfdep); 1349 if (error) 1350 break; 1351 continue; 1352 } 1353 error = linker_load_module(modname, lf); 1354 if (error) { 1355 printf("KLD %s: depends on %s - not available\n", 1356 lf->filename, modname); 1357 break; 1358 } 1359 } 1360 1361 if (error) 1362 return error; 1363 for (i = 0; i < deps->ls_length; i++) { 1364 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1365 if (mp->md_type != MDT_VERSION) 1366 continue; 1367 modname = linker_reloc_ptr(lf, mp->md_cval); 1368 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); 1369 if (mod == NULL) 1370 panic("no memory for module list"); 1371 mod->container = lf; 1372 mod->name = modname; 1373 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1374 } 1375 return error; 1376} 1377