29
30#include "opt_ddb.h"
31#include "opt_hwpmc_hooks.h"
32
33#include <sys/param.h>
34#include <sys/kernel.h>
35#include <sys/systm.h>
36#include <sys/malloc.h>
37#include <sys/sysproto.h>
38#include <sys/sysent.h>
39#include <sys/priv.h>
40#include <sys/proc.h>
41#include <sys/lock.h>
42#include <sys/mutex.h>
43#include <sys/sx.h>
44#include <sys/module.h>
45#include <sys/mount.h>
46#include <sys/linker.h>
47#include <sys/fcntl.h>
48#include <sys/jail.h>
49#include <sys/libkern.h>
50#include <sys/namei.h>
51#include <sys/vnode.h>
52#include <sys/syscallsubr.h>
53#include <sys/sysctl.h>
54
55#include <net/vnet.h>
56
57#include <security/mac/mac_framework.h>
58
59#include "linker_if.h"
60
61#ifdef HWPMC_HOOKS
62#include <sys/pmckern.h>
63#endif
64
65#ifdef KLD_DEBUG
66int kld_debug = 0;
67SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RW,
68 &kld_debug, 0, "Set various levels of KLD debug");
69#endif
70
71#define KLD_LOCK() sx_xlock(&kld_sx)
72#define KLD_UNLOCK() sx_xunlock(&kld_sx)
73#define KLD_LOCKED() sx_xlocked(&kld_sx)
74#define KLD_LOCK_ASSERT() do { \
75 if (!cold) \
76 sx_assert(&kld_sx, SX_XLOCKED); \
77} while (0)
78
79/*
80 * static char *linker_search_path(const char *name, struct mod_depend
81 * *verinfo);
82 */
83static const char *linker_basename(const char *path);
84
85/*
86 * Find a currently loaded file given its filename.
87 */
88static linker_file_t linker_find_file_by_name(const char* _filename);
89
90/*
91 * Find a currently loaded file given its file id.
92 */
93static linker_file_t linker_find_file_by_id(int _fileid);
94
95/* Metadata from the static kernel */
96SET_DECLARE(modmetadata_set, struct mod_metadata);
97
98MALLOC_DEFINE(M_LINKER, "linker", "kernel linker");
99
100linker_file_t linker_kernel_file;
101
102static struct sx kld_sx; /* kernel linker lock */
103
104/*
105 * Load counter used by clients to determine if a linker file has been
106 * re-loaded. This counter is incremented for each file load.
107 */
108static int loadcnt;
109
110static linker_class_list_t classes;
111static linker_file_list_t linker_files;
112static int next_file_id = 1;
113static int linker_no_more_classes = 0;
114
115#define LINKER_GET_NEXT_FILE_ID(a) do { \
116 linker_file_t lftmp; \
117 \
118 KLD_LOCK_ASSERT(); \
119retry: \
120 TAILQ_FOREACH(lftmp, &linker_files, link) { \
121 if (next_file_id == lftmp->id) { \
122 next_file_id++; \
123 goto retry; \
124 } \
125 } \
126 (a) = next_file_id; \
127} while(0)
128
129
130/* XXX wrong name; we're looking at version provision tags here, not modules */
131typedef TAILQ_HEAD(, modlist) modlisthead_t;
132struct modlist {
133 TAILQ_ENTRY(modlist) link; /* chain together all modules */
134 linker_file_t container;
135 const char *name;
136 int version;
137};
138typedef struct modlist *modlist_t;
139static modlisthead_t found_modules;
140
141static int linker_file_add_dependency(linker_file_t file,
142 linker_file_t dep);
143static caddr_t linker_file_lookup_symbol_internal(linker_file_t file,
144 const char* name, int deps);
145static int linker_load_module(const char *kldname,
146 const char *modname, struct linker_file *parent,
147 struct mod_depend *verinfo, struct linker_file **lfpp);
148static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo);
149
150static char *
151linker_strdup(const char *str)
152{
153 char *result;
154
155 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL)
156 strcpy(result, str);
157 return (result);
158}
159
160static void
161linker_init(void *arg)
162{
163
164 sx_init(&kld_sx, "kernel linker");
165 TAILQ_INIT(&classes);
166 TAILQ_INIT(&linker_files);
167}
168
169SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0);
170
171static void
172linker_stop_class_add(void *arg)
173{
174
175 linker_no_more_classes = 1;
176}
177
178SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL);
179
180int
181linker_add_class(linker_class_t lc)
182{
183
184 /*
185 * We disallow any class registration past SI_ORDER_ANY
186 * of SI_SUB_KLD. We bump the reference count to keep the
187 * ops from being freed.
188 */
189 if (linker_no_more_classes == 1)
190 return (EPERM);
191 kobj_class_compile((kobj_class_t) lc);
192 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */
193 TAILQ_INSERT_TAIL(&classes, lc, link);
194 return (0);
195}
196
197static void
198linker_file_sysinit(linker_file_t lf)
199{
200 struct sysinit **start, **stop, **sipp, **xipp, *save;
201
202 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
203 lf->filename));
204
205 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
206 return;
207 /*
208 * Perform a bubble sort of the system initialization objects by
209 * their subsystem (primary key) and order (secondary key).
210 *
211 * Since some things care about execution order, this is the operation
212 * which ensures continued function.
213 */
214 for (sipp = start; sipp < stop; sipp++) {
215 for (xipp = sipp + 1; xipp < stop; xipp++) {
216 if ((*sipp)->subsystem < (*xipp)->subsystem ||
217 ((*sipp)->subsystem == (*xipp)->subsystem &&
218 (*sipp)->order <= (*xipp)->order))
219 continue; /* skip */
220 save = *sipp;
221 *sipp = *xipp;
222 *xipp = save;
223 }
224 }
225
226 /*
227 * Traverse the (now) ordered list of system initialization tasks.
228 * Perform each task, and continue on to the next task.
229 */
230 mtx_lock(&Giant);
231 for (sipp = start; sipp < stop; sipp++) {
232 if ((*sipp)->subsystem == SI_SUB_DUMMY)
233 continue; /* skip dummy task(s) */
234
235 /* Call function */
236 (*((*sipp)->func)) ((*sipp)->udata);
237 }
238 mtx_unlock(&Giant);
239}
240
241static void
242linker_file_sysuninit(linker_file_t lf)
243{
244 struct sysinit **start, **stop, **sipp, **xipp, *save;
245
246 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n",
247 lf->filename));
248
249 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop,
250 NULL) != 0)
251 return;
252
253 /*
254 * Perform a reverse bubble sort of the system initialization objects
255 * by their subsystem (primary key) and order (secondary key).
256 *
257 * Since some things care about execution order, this is the operation
258 * which ensures continued function.
259 */
260 for (sipp = start; sipp < stop; sipp++) {
261 for (xipp = sipp + 1; xipp < stop; xipp++) {
262 if ((*sipp)->subsystem > (*xipp)->subsystem ||
263 ((*sipp)->subsystem == (*xipp)->subsystem &&
264 (*sipp)->order >= (*xipp)->order))
265 continue; /* skip */
266 save = *sipp;
267 *sipp = *xipp;
268 *xipp = save;
269 }
270 }
271
272 /*
273 * Traverse the (now) ordered list of system initialization tasks.
274 * Perform each task, and continue on to the next task.
275 */
276 mtx_lock(&Giant);
277 for (sipp = start; sipp < stop; sipp++) {
278 if ((*sipp)->subsystem == SI_SUB_DUMMY)
279 continue; /* skip dummy task(s) */
280
281 /* Call function */
282 (*((*sipp)->func)) ((*sipp)->udata);
283 }
284 mtx_unlock(&Giant);
285}
286
287static void
288linker_file_register_sysctls(linker_file_t lf)
289{
290 struct sysctl_oid **start, **stop, **oidp;
291
292 KLD_DPF(FILE,
293 ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
294 lf->filename));
295
296 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
297 return;
298
299 sysctl_lock();
300 for (oidp = start; oidp < stop; oidp++)
301 sysctl_register_oid(*oidp);
302 sysctl_unlock();
303}
304
305static void
306linker_file_unregister_sysctls(linker_file_t lf)
307{
308 struct sysctl_oid **start, **stop, **oidp;
309
310 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs"
311 " for %s\n", lf->filename));
312
313 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
314 return;
315
316 sysctl_lock();
317 for (oidp = start; oidp < stop; oidp++)
318 sysctl_unregister_oid(*oidp);
319 sysctl_unlock();
320}
321
322static int
323linker_file_register_modules(linker_file_t lf)
324{
325 struct mod_metadata **start, **stop, **mdp;
326 const moduledata_t *moddata;
327 int first_error, error;
328
329 KLD_DPF(FILE, ("linker_file_register_modules: registering modules"
330 " in %s\n", lf->filename));
331
332 if (linker_file_lookup_set(lf, "modmetadata_set", &start,
333 &stop, NULL) != 0) {
334 /*
335 * This fallback should be unnecessary, but if we get booted
336 * from boot2 instead of loader and we are missing our
337 * metadata then we have to try the best we can.
338 */
339 if (lf == linker_kernel_file) {
340 start = SET_BEGIN(modmetadata_set);
341 stop = SET_LIMIT(modmetadata_set);
342 } else
343 return (0);
344 }
345 first_error = 0;
346 for (mdp = start; mdp < stop; mdp++) {
347 if ((*mdp)->md_type != MDT_MODULE)
348 continue;
349 moddata = (*mdp)->md_data;
350 KLD_DPF(FILE, ("Registering module %s in %s\n",
351 moddata->name, lf->filename));
352 error = module_register(moddata, lf);
353 if (error) {
354 printf("Module %s failed to register: %d\n",
355 moddata->name, error);
356 if (first_error == 0)
357 first_error = error;
358 }
359 }
360 return (first_error);
361}
362
363static void
364linker_init_kernel_modules(void)
365{
366
367 linker_file_register_modules(linker_kernel_file);
368}
369
370SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules,
371 0);
372
373static int
374linker_load_file(const char *filename, linker_file_t *result)
375{
376 linker_class_t lc;
377 linker_file_t lf;
378 int foundfile, error;
379
380 /* Refuse to load modules if securelevel raised */
381 if (prison0.pr_securelevel > 0)
382 return (EPERM);
383
384 KLD_LOCK_ASSERT();
385 lf = linker_find_file_by_name(filename);
386 if (lf) {
387 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded,"
388 " incrementing refs\n", filename));
389 *result = lf;
390 lf->refs++;
391 return (0);
392 }
393 foundfile = 0;
394 error = 0;
395
396 /*
397 * We do not need to protect (lock) classes here because there is
398 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY)
399 * and there is no class deregistration mechanism at this time.
400 */
401 TAILQ_FOREACH(lc, &classes, link) {
402 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
403 filename));
404 error = LINKER_LOAD_FILE(lc, filename, &lf);
405 /*
406 * If we got something other than ENOENT, then it exists but
407 * we cannot load it for some other reason.
408 */
409 if (error != ENOENT)
410 foundfile = 1;
411 if (lf) {
412 error = linker_file_register_modules(lf);
413 if (error == EEXIST) {
414 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
415 return (error);
416 }
417 KLD_UNLOCK();
418 linker_file_register_sysctls(lf);
419 linker_file_sysinit(lf);
420 KLD_LOCK();
421 lf->flags |= LINKER_FILE_LINKED;
422 *result = lf;
423 return (0);
424 }
425 }
426 /*
427 * Less than ideal, but tells the user whether it failed to load or
428 * the module was not found.
429 */
430 if (foundfile) {
431
432 /*
433 * If the file type has not been recognized by the last try
434 * printout a message before to fail.
435 */
436 if (error == ENOSYS)
437 printf("linker_load_file: Unsupported file type\n");
438
439 /*
440 * Format not recognized or otherwise unloadable.
441 * When loading a module that is statically built into
442 * the kernel EEXIST percolates back up as the return
443 * value. Preserve this so that apps like sysinstall
444 * can recognize this special case and not post bogus
445 * dialog boxes.
446 */
447 if (error != EEXIST)
448 error = ENOEXEC;
449 } else
450 error = ENOENT; /* Nothing found */
451 return (error);
452}
453
454int
455linker_reference_module(const char *modname, struct mod_depend *verinfo,
456 linker_file_t *result)
457{
458 modlist_t mod;
459 int error;
460
461 KLD_LOCK();
462 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) {
463 *result = mod->container;
464 (*result)->refs++;
465 KLD_UNLOCK();
466 return (0);
467 }
468
469 error = linker_load_module(NULL, modname, NULL, verinfo, result);
470 KLD_UNLOCK();
471 return (error);
472}
473
474int
475linker_release_module(const char *modname, struct mod_depend *verinfo,
476 linker_file_t lf)
477{
478 modlist_t mod;
479 int error;
480
481 KLD_LOCK();
482 if (lf == NULL) {
483 KASSERT(modname != NULL,
484 ("linker_release_module: no file or name"));
485 mod = modlist_lookup2(modname, verinfo);
486 if (mod == NULL) {
487 KLD_UNLOCK();
488 return (ESRCH);
489 }
490 lf = mod->container;
491 } else
492 KASSERT(modname == NULL && verinfo == NULL,
493 ("linker_release_module: both file and name"));
494 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL);
495 KLD_UNLOCK();
496 return (error);
497}
498
499static linker_file_t
500linker_find_file_by_name(const char *filename)
501{
502 linker_file_t lf;
503 char *koname;
504
505 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
506 sprintf(koname, "%s.ko", filename);
507
508 KLD_LOCK_ASSERT();
509 TAILQ_FOREACH(lf, &linker_files, link) {
510 if (strcmp(lf->filename, koname) == 0)
511 break;
512 if (strcmp(lf->filename, filename) == 0)
513 break;
514 }
515 free(koname, M_LINKER);
516 return (lf);
517}
518
519static linker_file_t
520linker_find_file_by_id(int fileid)
521{
522 linker_file_t lf;
523
524 KLD_LOCK_ASSERT();
525 TAILQ_FOREACH(lf, &linker_files, link)
526 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED)
527 break;
528 return (lf);
529}
530
531int
532linker_file_foreach(linker_predicate_t *predicate, void *context)
533{
534 linker_file_t lf;
535 int retval = 0;
536
537 KLD_LOCK();
538 TAILQ_FOREACH(lf, &linker_files, link) {
539 retval = predicate(lf, context);
540 if (retval != 0)
541 break;
542 }
543 KLD_UNLOCK();
544 return (retval);
545}
546
547linker_file_t
548linker_make_file(const char *pathname, linker_class_t lc)
549{
550 linker_file_t lf;
551 const char *filename;
552
553 KLD_LOCK_ASSERT();
554 filename = linker_basename(pathname);
555
556 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname));
557 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK);
558 if (lf == NULL)
559 return (NULL);
560 lf->refs = 1;
561 lf->userrefs = 0;
562 lf->flags = 0;
563 lf->filename = linker_strdup(filename);
564 lf->pathname = linker_strdup(pathname);
565 LINKER_GET_NEXT_FILE_ID(lf->id);
566 lf->ndeps = 0;
567 lf->deps = NULL;
568 lf->loadcnt = ++loadcnt;
569 lf->sdt_probes = NULL;
570 lf->sdt_nprobes = 0;
571 STAILQ_INIT(&lf->common);
572 TAILQ_INIT(&lf->modules);
573 TAILQ_INSERT_TAIL(&linker_files, lf, link);
574 return (lf);
575}
576
577int
578linker_file_unload(linker_file_t file, int flags)
579{
580 module_t mod, next;
581 modlist_t ml, nextml;
582 struct common_symbol *cp;
583 int error, i;
584
585 /* Refuse to unload modules if securelevel raised. */
586 if (prison0.pr_securelevel > 0)
587 return (EPERM);
588
589 KLD_LOCK_ASSERT();
590 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
591
592 /* Easy case of just dropping a reference. */
593 if (file->refs > 1) {
594 file->refs--;
595 return (0);
596 }
597
598 KLD_DPF(FILE, ("linker_file_unload: file is unloading,"
599 " informing modules\n"));
600
601 /*
602 * Quiesce all the modules to give them a chance to veto the unload.
603 */
604 MOD_SLOCK;
605 for (mod = TAILQ_FIRST(&file->modules); mod;
606 mod = module_getfnext(mod)) {
607
608 error = module_quiesce(mod);
609 if (error != 0 && flags != LINKER_UNLOAD_FORCE) {
610 KLD_DPF(FILE, ("linker_file_unload: module %s"
611 " vetoed unload\n", module_getname(mod)));
612 /*
613 * XXX: Do we need to tell all the quiesced modules
614 * that they can resume work now via a new module
615 * event?
616 */
617 MOD_SUNLOCK;
618 return (error);
619 }
620 }
621 MOD_SUNLOCK;
622
623 /*
624 * Inform any modules associated with this file that they are
625 * being be unloaded.
626 */
627 MOD_XLOCK;
628 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
629 next = module_getfnext(mod);
630 MOD_XUNLOCK;
631
632 /*
633 * Give the module a chance to veto the unload.
634 */
635 if ((error = module_unload(mod)) != 0) {
636 KLD_DPF(FILE, ("linker_file_unload: module %s"
637 " failed unload\n", module_getname(mod)));
638 return (error);
639 }
640 MOD_XLOCK;
641 module_release(mod);
642 }
643 MOD_XUNLOCK;
644
645 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) {
646 if (ml->container == file) {
647 TAILQ_REMOVE(&found_modules, ml, link);
648 free(ml, M_LINKER);
649 }
650 }
651
652 /*
653 * Don't try to run SYSUNINITs if we are unloaded due to a
654 * link error.
655 */
656 if (file->flags & LINKER_FILE_LINKED) {
657 file->flags &= ~LINKER_FILE_LINKED;
658 KLD_UNLOCK();
659 linker_file_sysuninit(file);
660 linker_file_unregister_sysctls(file);
661 KLD_LOCK();
662 }
663 TAILQ_REMOVE(&linker_files, file, link);
664
665 if (file->deps) {
666 for (i = 0; i < file->ndeps; i++)
667 linker_file_unload(file->deps[i], flags);
668 free(file->deps, M_LINKER);
669 file->deps = NULL;
670 }
671 while ((cp = STAILQ_FIRST(&file->common)) != NULL) {
672 STAILQ_REMOVE_HEAD(&file->common, link);
673 free(cp, M_LINKER);
674 }
675
676 LINKER_UNLOAD(file);
677 if (file->filename) {
678 free(file->filename, M_LINKER);
679 file->filename = NULL;
680 }
681 if (file->pathname) {
682 free(file->pathname, M_LINKER);
683 file->pathname = NULL;
684 }
685 kobj_delete((kobj_t) file, M_LINKER);
686 return (0);
687}
688
689int
690linker_ctf_get(linker_file_t file, linker_ctf_t *lc)
691{
692 return (LINKER_CTF_GET(file, lc));
693}
694
695static int
696linker_file_add_dependency(linker_file_t file, linker_file_t dep)
697{
698 linker_file_t *newdeps;
699
700 KLD_LOCK_ASSERT();
701 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *),
702 M_LINKER, M_WAITOK | M_ZERO);
703 if (newdeps == NULL)
704 return (ENOMEM);
705
706 if (file->deps) {
707 bcopy(file->deps, newdeps,
708 file->ndeps * sizeof(linker_file_t *));
709 free(file->deps, M_LINKER);
710 }
711 file->deps = newdeps;
712 file->deps[file->ndeps] = dep;
713 file->ndeps++;
714 KLD_DPF(FILE, ("linker_file_add_dependency:"
715 " adding %s as dependency for %s\n",
716 dep->filename, file->filename));
717 return (0);
718}
719
720/*
721 * Locate a linker set and its contents. This is a helper function to avoid
722 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **.
723 * This function is used in this file so we can avoid having lots of (void **)
724 * casts.
725 */
726int
727linker_file_lookup_set(linker_file_t file, const char *name,
728 void *firstp, void *lastp, int *countp)
729{
730 int error, locked;
731
732 locked = KLD_LOCKED();
733 if (!locked)
734 KLD_LOCK();
735 error = LINKER_LOOKUP_SET(file, name, firstp, lastp, countp);
736 if (!locked)
737 KLD_UNLOCK();
738 return (error);
739}
740
741/*
742 * List all functions in a file.
743 */
744int
745linker_file_function_listall(linker_file_t lf,
746 linker_function_nameval_callback_t callback_func, void *arg)
747{
748 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg));
749}
750
751caddr_t
752linker_file_lookup_symbol(linker_file_t file, const char *name, int deps)
753{
754 caddr_t sym;
755 int locked;
756
757 locked = KLD_LOCKED();
758 if (!locked)
759 KLD_LOCK();
760 sym = linker_file_lookup_symbol_internal(file, name, deps);
761 if (!locked)
762 KLD_UNLOCK();
763 return (sym);
764}
765
766static caddr_t
767linker_file_lookup_symbol_internal(linker_file_t file, const char *name,
768 int deps)
769{
770 c_linker_sym_t sym;
771 linker_symval_t symval;
772 caddr_t address;
773 size_t common_size = 0;
774 int i;
775
776 KLD_LOCK_ASSERT();
777 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n",
778 file, name, deps));
779
780 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
781 LINKER_SYMBOL_VALUES(file, sym, &symval);
782 if (symval.value == 0)
783 /*
784 * For commons, first look them up in the
785 * dependencies and only allocate space if not found
786 * there.
787 */
788 common_size = symval.size;
789 else {
790 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol"
791 ".value=%p\n", symval.value));
792 return (symval.value);
793 }
794 }
795 if (deps) {
796 for (i = 0; i < file->ndeps; i++) {
797 address = linker_file_lookup_symbol_internal(
798 file->deps[i], name, 0);
799 if (address) {
800 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
801 " deps value=%p\n", address));
802 return (address);
803 }
804 }
805 }
806 if (common_size > 0) {
807 /*
808 * This is a common symbol which was not found in the
809 * dependencies. We maintain a simple common symbol table in
810 * the file object.
811 */
812 struct common_symbol *cp;
813
814 STAILQ_FOREACH(cp, &file->common, link) {
815 if (strcmp(cp->name, name) == 0) {
816 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
817 " old common value=%p\n", cp->address));
818 return (cp->address);
819 }
820 }
821 /*
822 * Round the symbol size up to align.
823 */
824 common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
825 cp = malloc(sizeof(struct common_symbol)
826 + common_size + strlen(name) + 1, M_LINKER,
827 M_WAITOK | M_ZERO);
828 cp->address = (caddr_t)(cp + 1);
829 cp->name = cp->address + common_size;
830 strcpy(cp->name, name);
831 bzero(cp->address, common_size);
832 STAILQ_INSERT_TAIL(&file->common, cp, link);
833
834 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common"
835 " value=%p\n", cp->address));
836 return (cp->address);
837 }
838 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
839 return (0);
840}
841
842/*
843 * Both DDB and stack(9) rely on the kernel linker to provide forward and
844 * backward lookup of symbols. However, DDB and sometimes stack(9) need to
845 * do this in a lockfree manner. We provide a set of internal helper
846 * routines to perform these operations without locks, and then wrappers that
847 * optionally lock.
848 *
849 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB.
850 */
851#ifdef DDB
852static int
853linker_debug_lookup(const char *symstr, c_linker_sym_t *sym)
854{
855 linker_file_t lf;
856
857 TAILQ_FOREACH(lf, &linker_files, link) {
858 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0)
859 return (0);
860 }
861 return (ENOENT);
862}
863#endif
864
865static int
866linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
867{
868 linker_file_t lf;
869 c_linker_sym_t best, es;
870 u_long diff, bestdiff, off;
871
872 best = 0;
873 off = (uintptr_t)value;
874 bestdiff = off;
875 TAILQ_FOREACH(lf, &linker_files, link) {
876 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
877 continue;
878 if (es != 0 && diff < bestdiff) {
879 best = es;
880 bestdiff = diff;
881 }
882 if (bestdiff == 0)
883 break;
884 }
885 if (best) {
886 *sym = best;
887 *diffp = bestdiff;
888 return (0);
889 } else {
890 *sym = 0;
891 *diffp = off;
892 return (ENOENT);
893 }
894}
895
896static int
897linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
898{
899 linker_file_t lf;
900
901 TAILQ_FOREACH(lf, &linker_files, link) {
902 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0)
903 return (0);
904 }
905 return (ENOENT);
906}
907
908static int
909linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen,
910 long *offset)
911{
912 linker_symval_t symval;
913 c_linker_sym_t sym;
914 int error;
915
916 *offset = 0;
917 error = linker_debug_search_symbol(value, &sym, offset);
918 if (error)
919 return (error);
920 error = linker_debug_symbol_values(sym, &symval);
921 if (error)
922 return (error);
923 strlcpy(buf, symval.name, buflen);
924 return (0);
925}
926
927/*
928 * DDB Helpers. DDB has to look across multiple files with their own symbol
929 * tables and string tables.
930 *
931 * Note that we do not obey list locking protocols here. We really don't need
932 * DDB to hang because somebody's got the lock held. We'll take the chance
933 * that the files list is inconsistant instead.
934 */
935#ifdef DDB
936int
937linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
938{
939
940 return (linker_debug_lookup(symstr, sym));
941}
942#endif
943
944int
945linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
946{
947
948 return (linker_debug_search_symbol(value, sym, diffp));
949}
950
951int
952linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
953{
954
955 return (linker_debug_symbol_values(sym, symval));
956}
957
958int
959linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen,
960 long *offset)
961{
962
963 return (linker_debug_search_symbol_name(value, buf, buflen, offset));
964}
965
966/*
967 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do
968 * obey locking protocols, and offer a significantly less complex interface.
969 */
970int
971linker_search_symbol_name(caddr_t value, char *buf, u_int buflen,
972 long *offset)
973{
974 int error;
975
976 KLD_LOCK();
977 error = linker_debug_search_symbol_name(value, buf, buflen, offset);
978 KLD_UNLOCK();
979 return (error);
980}
981
982/*
983 * Syscalls.
984 */
985int
986kern_kldload(struct thread *td, const char *file, int *fileid)
987{
988#ifdef HWPMC_HOOKS
989 struct pmckern_map_in pkm;
990#endif
991 const char *kldname, *modname;
992 linker_file_t lf;
993 int error;
994
995 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
996 return (error);
997
998 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0)
999 return (error);
1000
1001 /*
1002 * It is possible that kldloaded module will attach a new ifnet,
1003 * so vnet context must be set when this ocurs.
1004 */
1005 CURVNET_SET(TD_TO_VNET(td));
1006
1007 /*
1008 * If file does not contain a qualified name or any dot in it
1009 * (kldname.ko, or kldname.ver.ko) treat it as an interface
1010 * name.
1011 */
1012 if (index(file, '/') || index(file, '.')) {
1013 kldname = file;
1014 modname = NULL;
1015 } else {
1016 kldname = NULL;
1017 modname = file;
1018 }
1019
1020 KLD_LOCK();
1021 error = linker_load_module(kldname, modname, NULL, NULL, &lf);
1022 if (error)
1023 goto unlock;
1024#ifdef HWPMC_HOOKS
1025 pkm.pm_file = lf->filename;
1026 pkm.pm_address = (uintptr_t) lf->address;
1027 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm);
1028#endif
1029 lf->userrefs++;
1030 if (fileid != NULL)
1031 *fileid = lf->id;
1032unlock:
1033 KLD_UNLOCK();
1034 CURVNET_RESTORE();
1035 return (error);
1036}
1037
1038int
1039kldload(struct thread *td, struct kldload_args *uap)
1040{
1041 char *pathname = NULL;
1042 int error, fileid;
1043
1044 td->td_retval[0] = -1;
1045
1046 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1047 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL);
1048 if (error == 0) {
1049 error = kern_kldload(td, pathname, &fileid);
1050 if (error == 0)
1051 td->td_retval[0] = fileid;
1052 }
1053 free(pathname, M_TEMP);
1054 return (error);
1055}
1056
1057int
1058kern_kldunload(struct thread *td, int fileid, int flags)
1059{
1060#ifdef HWPMC_HOOKS
1061 struct pmckern_map_out pkm;
1062#endif
1063 linker_file_t lf;
1064 int error = 0;
1065
1066 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
1067 return (error);
1068
1069 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0)
1070 return (error);
1071
1072 CURVNET_SET(TD_TO_VNET(td));
1073 KLD_LOCK();
1074 lf = linker_find_file_by_id(fileid);
1075 if (lf) {
1076 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
1077
1078 /* Check if there are DTrace probes enabled on this file. */
1079 if (lf->nenabled > 0) {
1080 printf("kldunload: attempt to unload file that has"
1081 " DTrace probes enabled\n");
1082 error = EBUSY;
1083 } else if (lf->userrefs == 0) {
1084 /*
1085 * XXX: maybe LINKER_UNLOAD_FORCE should override ?
1086 */
1087 printf("kldunload: attempt to unload file that was"
1088 " loaded by the kernel\n");
1089 error = EBUSY;
1090 } else {
1091#ifdef HWPMC_HOOKS
1092 /* Save data needed by hwpmc(4) before unloading. */
1093 pkm.pm_address = (uintptr_t) lf->address;
1094 pkm.pm_size = lf->size;
1095#endif
1096 lf->userrefs--;
1097 error = linker_file_unload(lf, flags);
1098 if (error)
1099 lf->userrefs++;
1100 }
1101 } else
1102 error = ENOENT;
1103
1104#ifdef HWPMC_HOOKS
1105 if (error == 0)
1106 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm);
1107#endif
1108 KLD_UNLOCK();
1109 CURVNET_RESTORE();
1110 return (error);
1111}
1112
1113int
1114kldunload(struct thread *td, struct kldunload_args *uap)
1115{
1116
1117 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL));
1118}
1119
1120int
1121kldunloadf(struct thread *td, struct kldunloadf_args *uap)
1122{
1123
1124 if (uap->flags != LINKER_UNLOAD_NORMAL &&
1125 uap->flags != LINKER_UNLOAD_FORCE)
1126 return (EINVAL);
1127 return (kern_kldunload(td, uap->fileid, uap->flags));
1128}
1129
1130int
1131kldfind(struct thread *td, struct kldfind_args *uap)
1132{
1133 char *pathname;
1134 const char *filename;
1135 linker_file_t lf;
1136 int error;
1137
1138#ifdef MAC
1139 error = mac_kld_check_stat(td->td_ucred);
1140 if (error)
1141 return (error);
1142#endif
1143
1144 td->td_retval[0] = -1;
1145
1146 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1147 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0)
1148 goto out;
1149
1150 filename = linker_basename(pathname);
1151 KLD_LOCK();
1152 lf = linker_find_file_by_name(filename);
1153 if (lf)
1154 td->td_retval[0] = lf->id;
1155 else
1156 error = ENOENT;
1157 KLD_UNLOCK();
1158out:
1159 free(pathname, M_TEMP);
1160 return (error);
1161}
1162
1163int
1164kldnext(struct thread *td, struct kldnext_args *uap)
1165{
1166 linker_file_t lf;
1167 int error = 0;
1168
1169#ifdef MAC
1170 error = mac_kld_check_stat(td->td_ucred);
1171 if (error)
1172 return (error);
1173#endif
1174
1175 KLD_LOCK();
1176 if (uap->fileid == 0)
1177 lf = TAILQ_FIRST(&linker_files);
1178 else {
1179 lf = linker_find_file_by_id(uap->fileid);
1180 if (lf == NULL) {
1181 error = ENOENT;
1182 goto out;
1183 }
1184 lf = TAILQ_NEXT(lf, link);
1185 }
1186
1187 /* Skip partially loaded files. */
1188 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED))
1189 lf = TAILQ_NEXT(lf, link);
1190
1191 if (lf)
1192 td->td_retval[0] = lf->id;
1193 else
1194 td->td_retval[0] = 0;
1195out:
1196 KLD_UNLOCK();
1197 return (error);
1198}
1199
1200int
1201kldstat(struct thread *td, struct kldstat_args *uap)
1202{
1203 struct kld_file_stat stat;
1204 linker_file_t lf;
1205 int error, namelen, version, version_num;
1206
1207 /*
1208 * Check the version of the user's structure.
1209 */
1210 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) != 0)
1211 return (error);
1212 if (version == sizeof(struct kld_file_stat_1))
1213 version_num = 1;
1214 else if (version == sizeof(struct kld_file_stat))
1215 version_num = 2;
1216 else
1217 return (EINVAL);
1218
1219#ifdef MAC
1220 error = mac_kld_check_stat(td->td_ucred);
1221 if (error)
1222 return (error);
1223#endif
1224
1225 KLD_LOCK();
1226 lf = linker_find_file_by_id(uap->fileid);
1227 if (lf == NULL) {
1228 KLD_UNLOCK();
1229 return (ENOENT);
1230 }
1231
1232 /* Version 1 fields: */
1233 namelen = strlen(lf->filename) + 1;
1234 if (namelen > MAXPATHLEN)
1235 namelen = MAXPATHLEN;
1236 bcopy(lf->filename, &stat.name[0], namelen);
1237 stat.refs = lf->refs;
1238 stat.id = lf->id;
1239 stat.address = lf->address;
1240 stat.size = lf->size;
1241 if (version_num > 1) {
1242 /* Version 2 fields: */
1243 namelen = strlen(lf->pathname) + 1;
1244 if (namelen > MAXPATHLEN)
1245 namelen = MAXPATHLEN;
1246 bcopy(lf->pathname, &stat.pathname[0], namelen);
1247 }
1248 KLD_UNLOCK();
1249
1250 td->td_retval[0] = 0;
1251
1252 return (copyout(&stat, uap->stat, version));
1253}
1254
1255int
1256kldfirstmod(struct thread *td, struct kldfirstmod_args *uap)
1257{
1258 linker_file_t lf;
1259 module_t mp;
1260 int error = 0;
1261
1262#ifdef MAC
1263 error = mac_kld_check_stat(td->td_ucred);
1264 if (error)
1265 return (error);
1266#endif
1267
1268 KLD_LOCK();
1269 lf = linker_find_file_by_id(uap->fileid);
1270 if (lf) {
1271 MOD_SLOCK;
1272 mp = TAILQ_FIRST(&lf->modules);
1273 if (mp != NULL)
1274 td->td_retval[0] = module_getid(mp);
1275 else
1276 td->td_retval[0] = 0;
1277 MOD_SUNLOCK;
1278 } else
1279 error = ENOENT;
1280 KLD_UNLOCK();
1281 return (error);
1282}
1283
1284int
1285kldsym(struct thread *td, struct kldsym_args *uap)
1286{
1287 char *symstr = NULL;
1288 c_linker_sym_t sym;
1289 linker_symval_t symval;
1290 linker_file_t lf;
1291 struct kld_sym_lookup lookup;
1292 int error = 0;
1293
1294#ifdef MAC
1295 error = mac_kld_check_stat(td->td_ucred);
1296 if (error)
1297 return (error);
1298#endif
1299
1300 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0)
1301 return (error);
1302 if (lookup.version != sizeof(lookup) ||
1303 uap->cmd != KLDSYM_LOOKUP)
1304 return (EINVAL);
1305 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1306 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
1307 goto out;
1308 KLD_LOCK();
1309 if (uap->fileid != 0) {
1310 lf = linker_find_file_by_id(uap->fileid);
1311 if (lf == NULL)
1312 error = ENOENT;
1313 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1314 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1315 lookup.symvalue = (uintptr_t) symval.value;
1316 lookup.symsize = symval.size;
1317 error = copyout(&lookup, uap->data, sizeof(lookup));
1318 } else
1319 error = ENOENT;
1320 } else {
1321 TAILQ_FOREACH(lf, &linker_files, link) {
1322 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1323 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1324 lookup.symvalue = (uintptr_t)symval.value;
1325 lookup.symsize = symval.size;
1326 error = copyout(&lookup, uap->data,
1327 sizeof(lookup));
1328 break;
1329 }
1330 }
1331 if (lf == NULL)
1332 error = ENOENT;
1333 }
1334 KLD_UNLOCK();
1335out:
1336 free(symstr, M_TEMP);
1337 return (error);
1338}
1339
1340/*
1341 * Preloaded module support
1342 */
1343
1344static modlist_t
1345modlist_lookup(const char *name, int ver)
1346{
1347 modlist_t mod;
1348
1349 TAILQ_FOREACH(mod, &found_modules, link) {
1350 if (strcmp(mod->name, name) == 0 &&
1351 (ver == 0 || mod->version == ver))
1352 return (mod);
1353 }
1354 return (NULL);
1355}
1356
1357static modlist_t
1358modlist_lookup2(const char *name, struct mod_depend *verinfo)
1359{
1360 modlist_t mod, bestmod;
1361 int ver;
1362
1363 if (verinfo == NULL)
1364 return (modlist_lookup(name, 0));
1365 bestmod = NULL;
1366 TAILQ_FOREACH(mod, &found_modules, link) {
1367 if (strcmp(mod->name, name) != 0)
1368 continue;
1369 ver = mod->version;
1370 if (ver == verinfo->md_ver_preferred)
1371 return (mod);
1372 if (ver >= verinfo->md_ver_minimum &&
1373 ver <= verinfo->md_ver_maximum &&
1374 (bestmod == NULL || ver > bestmod->version))
1375 bestmod = mod;
1376 }
1377 return (bestmod);
1378}
1379
1380static modlist_t
1381modlist_newmodule(const char *modname, int version, linker_file_t container)
1382{
1383 modlist_t mod;
1384
1385 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO);
1386 if (mod == NULL)
1387 panic("no memory for module list");
1388 mod->container = container;
1389 mod->name = modname;
1390 mod->version = version;
1391 TAILQ_INSERT_TAIL(&found_modules, mod, link);
1392 return (mod);
1393}
1394
1395static void
1396linker_addmodules(linker_file_t lf, struct mod_metadata **start,
1397 struct mod_metadata **stop, int preload)
1398{
1399 struct mod_metadata *mp, **mdp;
1400 const char *modname;
1401 int ver;
1402
1403 for (mdp = start; mdp < stop; mdp++) {
1404 mp = *mdp;
1405 if (mp->md_type != MDT_VERSION)
1406 continue;
1407 modname = mp->md_cval;
1408 ver = ((struct mod_version *)mp->md_data)->mv_version;
1409 if (modlist_lookup(modname, ver) != NULL) {
1410 printf("module %s already present!\n", modname);
1411 /* XXX what can we do? this is a build error. :-( */
1412 continue;
1413 }
1414 modlist_newmodule(modname, ver, lf);
1415 }
1416}
1417
1418static void
1419linker_preload(void *arg)
1420{
1421 caddr_t modptr;
1422 const char *modname, *nmodname;
1423 char *modtype;
1424 linker_file_t lf, nlf;
1425 linker_class_t lc;
1426 int error;
1427 linker_file_list_t loaded_files;
1428 linker_file_list_t depended_files;
1429 struct mod_metadata *mp, *nmp;
1430 struct mod_metadata **start, **stop, **mdp, **nmdp;
1431 struct mod_depend *verinfo;
1432 int nver;
1433 int resolves;
1434 modlist_t mod;
1435 struct sysinit **si_start, **si_stop;
1436
1437 TAILQ_INIT(&loaded_files);
1438 TAILQ_INIT(&depended_files);
1439 TAILQ_INIT(&found_modules);
1440 error = 0;
1441
1442 modptr = NULL;
1443 while ((modptr = preload_search_next_name(modptr)) != NULL) {
1444 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
1445 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
1446 if (modname == NULL) {
1447 printf("Preloaded module at %p does not have a"
1448 " name!\n", modptr);
1449 continue;
1450 }
1451 if (modtype == NULL) {
1452 printf("Preloaded module at %p does not have a type!\n",
1453 modptr);
1454 continue;
1455 }
1456 if (bootverbose)
1457 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname,
1458 modptr);
1459 lf = NULL;
1460 TAILQ_FOREACH(lc, &classes, link) {
1461 error = LINKER_LINK_PRELOAD(lc, modname, &lf);
1462 if (!error)
1463 break;
1464 lf = NULL;
1465 }
1466 if (lf)
1467 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
1468 }
1469
1470 /*
1471 * First get a list of stuff in the kernel.
1472 */
1473 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start,
1474 &stop, NULL) == 0)
1475 linker_addmodules(linker_kernel_file, start, stop, 1);
1476
1477 /*
1478 * This is a once-off kinky bubble sort to resolve relocation
1479 * dependency requirements.
1480 */
1481restart:
1482 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1483 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1484 &stop, NULL);
1485 /*
1486 * First, look to see if we would successfully link with this
1487 * stuff.
1488 */
1489 resolves = 1; /* unless we know otherwise */
1490 if (!error) {
1491 for (mdp = start; mdp < stop; mdp++) {
1492 mp = *mdp;
1493 if (mp->md_type != MDT_DEPEND)
1494 continue;
1495 modname = mp->md_cval;
1496 verinfo = mp->md_data;
1497 for (nmdp = start; nmdp < stop; nmdp++) {
1498 nmp = *nmdp;
1499 if (nmp->md_type != MDT_VERSION)
1500 continue;
1501 nmodname = nmp->md_cval;
1502 if (strcmp(modname, nmodname) == 0)
1503 break;
1504 }
1505 if (nmdp < stop) /* it's a self reference */
1506 continue;
1507
1508 /*
1509 * ok, the module isn't here yet, we
1510 * are not finished
1511 */
1512 if (modlist_lookup2(modname, verinfo) == NULL)
1513 resolves = 0;
1514 }
1515 }
1516 /*
1517 * OK, if we found our modules, we can link. So, "provide"
1518 * the modules inside and add it to the end of the link order
1519 * list.
1520 */
1521 if (resolves) {
1522 if (!error) {
1523 for (mdp = start; mdp < stop; mdp++) {
1524 mp = *mdp;
1525 if (mp->md_type != MDT_VERSION)
1526 continue;
1527 modname = mp->md_cval;
1528 nver = ((struct mod_version *)
1529 mp->md_data)->mv_version;
1530 if (modlist_lookup(modname,
1531 nver) != NULL) {
1532 printf("module %s already"
1533 " present!\n", modname);
1534 TAILQ_REMOVE(&loaded_files,
1535 lf, loaded);
1536 linker_file_unload(lf,
1537 LINKER_UNLOAD_FORCE);
1538 /* we changed tailq next ptr */
1539 goto restart;
1540 }
1541 modlist_newmodule(modname, nver, lf);
1542 }
1543 }
1544 TAILQ_REMOVE(&loaded_files, lf, loaded);
1545 TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
1546 /*
1547 * Since we provided modules, we need to restart the
1548 * sort so that the previous files that depend on us
1549 * have a chance. Also, we've busted the tailq next
1550 * pointer with the REMOVE.
1551 */
1552 goto restart;
1553 }
1554 }
1555
1556 /*
1557 * At this point, we check to see what could not be resolved..
1558 */
1559 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) {
1560 TAILQ_REMOVE(&loaded_files, lf, loaded);
1561 printf("KLD file %s is missing dependencies\n", lf->filename);
1562 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1563 }
1564
1565 /*
1566 * We made it. Finish off the linking in the order we determined.
1567 */
1568 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) {
1569 if (linker_kernel_file) {
1570 linker_kernel_file->refs++;
1571 error = linker_file_add_dependency(lf,
1572 linker_kernel_file);
1573 if (error)
1574 panic("cannot add dependency");
1575 }
1576 lf->userrefs++; /* so we can (try to) kldunload it */
1577 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1578 &stop, NULL);
1579 if (!error) {
1580 for (mdp = start; mdp < stop; mdp++) {
1581 mp = *mdp;
1582 if (mp->md_type != MDT_DEPEND)
1583 continue;
1584 modname = mp->md_cval;
1585 verinfo = mp->md_data;
1586 mod = modlist_lookup2(modname, verinfo);
1587 if (mod == NULL) {
1588 printf("KLD file %s - cannot find "
1589 "dependency \"%s\"\n",
1590 lf->filename, modname);
1591 goto fail;
1592 }
1593 /* Don't count self-dependencies */
1594 if (lf == mod->container)
1595 continue;
1596 mod->container->refs++;
1597 error = linker_file_add_dependency(lf,
1598 mod->container);
1599 if (error)
1600 panic("cannot add dependency");
1601 }
1602 }
1603 /*
1604 * Now do relocation etc using the symbol search paths
1605 * established by the dependencies
1606 */
1607 error = LINKER_LINK_PRELOAD_FINISH(lf);
1608 if (error) {
1609 printf("KLD file %s - could not finalize loading\n",
1610 lf->filename);
1611 goto fail;
1612 }
1613 linker_file_register_modules(lf);
1614 if (linker_file_lookup_set(lf, "sysinit_set", &si_start,
1615 &si_stop, NULL) == 0)
1616 sysinit_add(si_start, si_stop);
1617 linker_file_register_sysctls(lf);
1618 lf->flags |= LINKER_FILE_LINKED;
1619 continue;
1620fail:
1621 TAILQ_REMOVE(&depended_files, lf, loaded);
1622 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1623 }
1624 /* woohoo! we made it! */
1625}
1626
1627SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0);
1628
1629/*
1630 * Search for a not-loaded module by name.
1631 *
1632 * Modules may be found in the following locations:
1633 *
1634 * - preloaded (result is just the module name) - on disk (result is full path
1635 * to module)
1636 *
1637 * If the module name is qualified in any way (contains path, etc.) the we
1638 * simply return a copy of it.
1639 *
1640 * The search path can be manipulated via sysctl. Note that we use the ';'
1641 * character as a separator to be consistent with the bootloader.
1642 */
1643
1644static char linker_hintfile[] = "linker.hints";
1645static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules";
1646
1647SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path,
1648 sizeof(linker_path), "module load search path");
1649
1650TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
1651
1652static char *linker_ext_list[] = {
1653 "",
1654 ".ko",
1655 NULL
1656};
1657
1658/*
1659 * Check if file actually exists either with or without extension listed in
1660 * the linker_ext_list. (probably should be generic for the rest of the
1661 * kernel)
1662 */
1663static char *
1664linker_lookup_file(const char *path, int pathlen, const char *name,
1665 int namelen, struct vattr *vap)
1666{
1667 struct nameidata nd;
1668 struct thread *td = curthread; /* XXX */
1669 char *result, **cpp, *sep;
1670 int error, len, extlen, reclen, flags, vfslocked;
1671 enum vtype type;
1672
1673 extlen = 0;
1674 for (cpp = linker_ext_list; *cpp; cpp++) {
1675 len = strlen(*cpp);
1676 if (len > extlen)
1677 extlen = len;
1678 }
1679 extlen++; /* trailing '\0' */
1680 sep = (path[pathlen - 1] != '/') ? "/" : "";
1681
1682 reclen = pathlen + strlen(sep) + namelen + extlen + 1;
1683 result = malloc(reclen, M_LINKER, M_WAITOK);
1684 for (cpp = linker_ext_list; *cpp; cpp++) {
1685 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep,
1686 namelen, name, *cpp);
1687 /*
1688 * Attempt to open the file, and return the path if
1689 * we succeed and it's a regular file.
1690 */
1691 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, result, td);
1692 flags = FREAD;
1693 error = vn_open(&nd, &flags, 0, NULL);
1694 if (error == 0) {
1695 vfslocked = NDHASGIANT(&nd);
1696 NDFREE(&nd, NDF_ONLY_PNBUF);
1697 type = nd.ni_vp->v_type;
1698 if (vap)
1699 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred);
1700 VOP_UNLOCK(nd.ni_vp, 0);
1701 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
1702 VFS_UNLOCK_GIANT(vfslocked);
1703 if (type == VREG)
1704 return (result);
1705 }
1706 }
1707 free(result, M_LINKER);
1708 return (NULL);
1709}
1710
1711#define INT_ALIGN(base, ptr) ptr = \
1712 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1))
1713
1714/*
1715 * Lookup KLD which contains requested module in the "linker.hints" file. If
1716 * version specification is available, then try to find the best KLD.
1717 * Otherwise just find the latest one.
1718 */
1719static char *
1720linker_hints_lookup(const char *path, int pathlen, const char *modname,
1721 int modnamelen, struct mod_depend *verinfo)
1722{
1723 struct thread *td = curthread; /* XXX */
1724 struct ucred *cred = td ? td->td_ucred : NULL;
1725 struct nameidata nd;
1726 struct vattr vattr, mattr;
1727 u_char *hints = NULL;
1728 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep;
1729 int error, ival, bestver, *intp, reclen, found, flags, clen, blen;
1730 int vfslocked = 0;
1731
1732 result = NULL;
1733 bestver = found = 0;
1734
1735 sep = (path[pathlen - 1] != '/') ? "/" : "";
1736 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen +
1737 strlen(sep) + 1;
1738 pathbuf = malloc(reclen, M_LINKER, M_WAITOK);
1739 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep,
1740 linker_hintfile);
1741
1742 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, pathbuf, td);
1743 flags = FREAD;
1744 error = vn_open(&nd, &flags, 0, NULL);
1745 if (error)
1746 goto bad;
1747 vfslocked = NDHASGIANT(&nd);
1748 NDFREE(&nd, NDF_ONLY_PNBUF);
1749 if (nd.ni_vp->v_type != VREG)
1750 goto bad;
1751 best = cp = NULL;
1752 error = VOP_GETATTR(nd.ni_vp, &vattr, cred);
1753 if (error)
1754 goto bad;
1755 /*
1756 * XXX: we need to limit this number to some reasonable value
1757 */
1758 if (vattr.va_size > 100 * 1024) {
1759 printf("hints file too large %ld\n", (long)vattr.va_size);
1760 goto bad;
1761 }
1762 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK);
1763 if (hints == NULL)
1764 goto bad;
1765 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0,
1766 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td);
1767 if (error)
1768 goto bad;
1769 VOP_UNLOCK(nd.ni_vp, 0);
1770 vn_close(nd.ni_vp, FREAD, cred, td);
1771 VFS_UNLOCK_GIANT(vfslocked);
1772 nd.ni_vp = NULL;
1773 if (reclen != 0) {
1774 printf("can't read %d\n", reclen);
1775 goto bad;
1776 }
1777 intp = (int *)hints;
1778 ival = *intp++;
1779 if (ival != LINKER_HINTS_VERSION) {
1780 printf("hints file version mismatch %d\n", ival);
1781 goto bad;
1782 }
1783 bufend = hints + vattr.va_size;
1784 recptr = (u_char *)intp;
1785 clen = blen = 0;
1786 while (recptr < bufend && !found) {
1787 intp = (int *)recptr;
1788 reclen = *intp++;
1789 ival = *intp++;
1790 cp = (char *)intp;
1791 switch (ival) {
1792 case MDT_VERSION:
1793 clen = *cp++;
1794 if (clen != modnamelen || bcmp(cp, modname, clen) != 0)
1795 break;
1796 cp += clen;
1797 INT_ALIGN(hints, cp);
1798 ival = *(int *)cp;
1799 cp += sizeof(int);
1800 clen = *cp++;
1801 if (verinfo == NULL ||
1802 ival == verinfo->md_ver_preferred) {
1803 found = 1;
1804 break;
1805 }
1806 if (ival >= verinfo->md_ver_minimum &&
1807 ival <= verinfo->md_ver_maximum &&
1808 ival > bestver) {
1809 bestver = ival;
1810 best = cp;
1811 blen = clen;
1812 }
1813 break;
1814 default:
1815 break;
1816 }
1817 recptr += reclen + sizeof(int);
1818 }
1819 /*
1820 * Finally check if KLD is in the place
1821 */
1822 if (found)
1823 result = linker_lookup_file(path, pathlen, cp, clen, &mattr);
1824 else if (best)
1825 result = linker_lookup_file(path, pathlen, best, blen, &mattr);
1826
1827 /*
1828 * KLD is newer than hints file. What we should do now?
1829 */
1830 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >))
1831 printf("warning: KLD '%s' is newer than the linker.hints"
1832 " file\n", result);
1833bad:
1834 free(pathbuf, M_LINKER);
1835 if (hints)
1836 free(hints, M_TEMP);
1837 if (nd.ni_vp != NULL) {
1838 VOP_UNLOCK(nd.ni_vp, 0);
1839 vn_close(nd.ni_vp, FREAD, cred, td);
1840 VFS_UNLOCK_GIANT(vfslocked);
1841 }
1842 /*
1843 * If nothing found or hints is absent - fallback to the old
1844 * way by using "kldname[.ko]" as module name.
1845 */
1846 if (!found && !bestver && result == NULL)
1847 result = linker_lookup_file(path, pathlen, modname,
1848 modnamelen, NULL);
1849 return (result);
1850}
1851
1852/*
1853 * Lookup KLD which contains requested module in the all directories.
1854 */
1855static char *
1856linker_search_module(const char *modname, int modnamelen,
1857 struct mod_depend *verinfo)
1858{
1859 char *cp, *ep, *result;
1860
1861 /*
1862 * traverse the linker path
1863 */
1864 for (cp = linker_path; *cp; cp = ep + 1) {
1865 /* find the end of this component */
1866 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++);
1867 result = linker_hints_lookup(cp, ep - cp, modname,
1868 modnamelen, verinfo);
1869 if (result != NULL)
1870 return (result);
1871 if (*ep == 0)
1872 break;
1873 }
1874 return (NULL);
1875}
1876
1877/*
1878 * Search for module in all directories listed in the linker_path.
1879 */
1880static char *
1881linker_search_kld(const char *name)
1882{
1883 char *cp, *ep, *result;
1884 int len;
1885
1886 /* qualified at all? */
1887 if (index(name, '/'))
1888 return (linker_strdup(name));
1889
1890 /* traverse the linker path */
1891 len = strlen(name);
1892 for (ep = linker_path; *ep; ep++) {
1893 cp = ep;
1894 /* find the end of this component */
1895 for (; *ep != 0 && *ep != ';'; ep++);
1896 result = linker_lookup_file(cp, ep - cp, name, len, NULL);
1897 if (result != NULL)
1898 return (result);
1899 }
1900 return (NULL);
1901}
1902
1903static const char *
1904linker_basename(const char *path)
1905{
1906 const char *filename;
1907
1908 filename = rindex(path, '/');
1909 if (filename == NULL)
1910 return path;
1911 if (filename[1])
1912 filename++;
1913 return (filename);
1914}
1915
1916#ifdef HWPMC_HOOKS
1917/*
1918 * Inform hwpmc about the set of kernel modules currently loaded.
1919 */
1920void *
1921linker_hwpmc_list_objects(void)
1922{
1923 linker_file_t lf;
1924 struct pmckern_map_in *kobase;
1925 int i, nmappings;
1926
1927 nmappings = 0;
1928 KLD_LOCK();
1929 TAILQ_FOREACH(lf, &linker_files, link)
1930 nmappings++;
1931
1932 /* Allocate nmappings + 1 entries. */
1933 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in),
1934 M_LINKER, M_WAITOK | M_ZERO);
1935 i = 0;
1936 TAILQ_FOREACH(lf, &linker_files, link) {
1937
1938 /* Save the info for this linker file. */
1939 kobase[i].pm_file = lf->filename;
1940 kobase[i].pm_address = (uintptr_t)lf->address;
1941 i++;
1942 }
1943 KLD_UNLOCK();
1944
1945 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?"));
1946
1947 /* The last entry of the malloced area comprises of all zeros. */
1948 KASSERT(kobase[i].pm_file == NULL,
1949 ("linker_hwpmc_list_objects: last object not NULL"));
1950
1951 return ((void *)kobase);
1952}
1953#endif
1954
1955/*
1956 * Find a file which contains given module and load it, if "parent" is not
1957 * NULL, register a reference to it.
1958 */
1959static int
1960linker_load_module(const char *kldname, const char *modname,
1961 struct linker_file *parent, struct mod_depend *verinfo,
1962 struct linker_file **lfpp)
1963{
1964 linker_file_t lfdep;
1965 const char *filename;
1966 char *pathname;
1967 int error;
1968
1969 KLD_LOCK_ASSERT();
1970 if (modname == NULL) {
1971 /*
1972 * We have to load KLD
1973 */
1974 KASSERT(verinfo == NULL, ("linker_load_module: verinfo"
1975 " is not NULL"));
1976 pathname = linker_search_kld(kldname);
1977 } else {
1978 if (modlist_lookup2(modname, verinfo) != NULL)
1979 return (EEXIST);
1980 if (kldname != NULL)
1981 pathname = linker_strdup(kldname);
1982 else if (rootvnode == NULL)
1983 pathname = NULL;
1984 else
1985 /*
1986 * Need to find a KLD with required module
1987 */
1988 pathname = linker_search_module(modname,
1989 strlen(modname), verinfo);
1990 }
1991 if (pathname == NULL)
1992 return (ENOENT);
1993
1994 /*
1995 * Can't load more than one file with the same basename XXX:
1996 * Actually it should be possible to have multiple KLDs with
1997 * the same basename but different path because they can
1998 * provide different versions of the same modules.
1999 */
2000 filename = linker_basename(pathname);
2001 if (linker_find_file_by_name(filename))
2002 error = EEXIST;
2003 else do {
2004 error = linker_load_file(pathname, &lfdep);
2005 if (error)
2006 break;
2007 if (modname && verinfo &&
2008 modlist_lookup2(modname, verinfo) == NULL) {
2009 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE);
2010 error = ENOENT;
2011 break;
2012 }
2013 if (parent) {
2014 error = linker_file_add_dependency(parent, lfdep);
2015 if (error)
2016 break;
2017 }
2018 if (lfpp)
2019 *lfpp = lfdep;
2020 } while (0);
2021 free(pathname, M_LINKER);
2022 return (error);
2023}
2024
2025/*
2026 * This routine is responsible for finding dependencies of userland initiated
2027 * kldload(2)'s of files.
2028 */
2029int
2030linker_load_dependencies(linker_file_t lf)
2031{
2032 linker_file_t lfdep;
2033 struct mod_metadata **start, **stop, **mdp, **nmdp;
2034 struct mod_metadata *mp, *nmp;
2035 struct mod_depend *verinfo;
2036 modlist_t mod;
2037 const char *modname, *nmodname;
2038 int ver, error = 0, count;
2039
2040 /*
2041 * All files are dependant on /kernel.
2042 */
2043 KLD_LOCK_ASSERT();
2044 if (linker_kernel_file) {
2045 linker_kernel_file->refs++;
2046 error = linker_file_add_dependency(lf, linker_kernel_file);
2047 if (error)
2048 return (error);
2049 }
2050 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop,
2051 &count) != 0)
2052 return (0);
2053 for (mdp = start; mdp < stop; mdp++) {
2054 mp = *mdp;
2055 if (mp->md_type != MDT_VERSION)
2056 continue;
2057 modname = mp->md_cval;
2058 ver = ((struct mod_version *)mp->md_data)->mv_version;
2059 mod = modlist_lookup(modname, ver);
2060 if (mod != NULL) {
2061 printf("interface %s.%d already present in the KLD"
2062 " '%s'!\n", modname, ver,
2063 mod->container->filename);
2064 return (EEXIST);
2065 }
2066 }
2067
2068 for (mdp = start; mdp < stop; mdp++) {
2069 mp = *mdp;
2070 if (mp->md_type != MDT_DEPEND)
2071 continue;
2072 modname = mp->md_cval;
2073 verinfo = mp->md_data;
2074 nmodname = NULL;
2075 for (nmdp = start; nmdp < stop; nmdp++) {
2076 nmp = *nmdp;
2077 if (nmp->md_type != MDT_VERSION)
2078 continue;
2079 nmodname = nmp->md_cval;
2080 if (strcmp(modname, nmodname) == 0)
2081 break;
2082 }
2083 if (nmdp < stop)/* early exit, it's a self reference */
2084 continue;
2085 mod = modlist_lookup2(modname, verinfo);
2086 if (mod) { /* woohoo, it's loaded already */
2087 lfdep = mod->container;
2088 lfdep->refs++;
2089 error = linker_file_add_dependency(lf, lfdep);
2090 if (error)
2091 break;
2092 continue;
2093 }
2094 error = linker_load_module(NULL, modname, lf, verinfo, NULL);
2095 if (error) {
2096 printf("KLD %s: depends on %s - not available or"
2097 " version mismatch\n", lf->filename, modname);
2098 break;
2099 }
2100 }
2101
2102 if (error)
2103 return (error);
2104 linker_addmodules(lf, start, stop, 0);
2105 return (error);
2106}
2107
2108static int
2109sysctl_kern_function_list_iterate(const char *name, void *opaque)
2110{
2111 struct sysctl_req *req;
2112
2113 req = opaque;
2114 return (SYSCTL_OUT(req, name, strlen(name) + 1));
2115}
2116
2117/*
2118 * Export a nul-separated, double-nul-terminated list of all function names
2119 * in the kernel.
2120 */
2121static int
2122sysctl_kern_function_list(SYSCTL_HANDLER_ARGS)
2123{
2124 linker_file_t lf;
2125 int error;
2126
2127#ifdef MAC
2128 error = mac_kld_check_stat(req->td->td_ucred);
2129 if (error)
2130 return (error);
2131#endif
2132 error = sysctl_wire_old_buffer(req, 0);
2133 if (error != 0)
2134 return (error);
2135 KLD_LOCK();
2136 TAILQ_FOREACH(lf, &linker_files, link) {
2137 error = LINKER_EACH_FUNCTION_NAME(lf,
2138 sysctl_kern_function_list_iterate, req);
2139 if (error) {
2140 KLD_UNLOCK();
2141 return (error);
2142 }
2143 }
2144 KLD_UNLOCK();
2145 return (SYSCTL_OUT(req, "", 1));
2146}
2147
| 29
30#include "opt_ddb.h"
31#include "opt_hwpmc_hooks.h"
32
33#include <sys/param.h>
34#include <sys/kernel.h>
35#include <sys/systm.h>
36#include <sys/malloc.h>
37#include <sys/sysproto.h>
38#include <sys/sysent.h>
39#include <sys/priv.h>
40#include <sys/proc.h>
41#include <sys/lock.h>
42#include <sys/mutex.h>
43#include <sys/sx.h>
44#include <sys/module.h>
45#include <sys/mount.h>
46#include <sys/linker.h>
47#include <sys/fcntl.h>
48#include <sys/jail.h>
49#include <sys/libkern.h>
50#include <sys/namei.h>
51#include <sys/vnode.h>
52#include <sys/syscallsubr.h>
53#include <sys/sysctl.h>
54
55#include <net/vnet.h>
56
57#include <security/mac/mac_framework.h>
58
59#include "linker_if.h"
60
61#ifdef HWPMC_HOOKS
62#include <sys/pmckern.h>
63#endif
64
65#ifdef KLD_DEBUG
66int kld_debug = 0;
67SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RW,
68 &kld_debug, 0, "Set various levels of KLD debug");
69#endif
70
71#define KLD_LOCK() sx_xlock(&kld_sx)
72#define KLD_UNLOCK() sx_xunlock(&kld_sx)
73#define KLD_LOCKED() sx_xlocked(&kld_sx)
74#define KLD_LOCK_ASSERT() do { \
75 if (!cold) \
76 sx_assert(&kld_sx, SX_XLOCKED); \
77} while (0)
78
79/*
80 * static char *linker_search_path(const char *name, struct mod_depend
81 * *verinfo);
82 */
83static const char *linker_basename(const char *path);
84
85/*
86 * Find a currently loaded file given its filename.
87 */
88static linker_file_t linker_find_file_by_name(const char* _filename);
89
90/*
91 * Find a currently loaded file given its file id.
92 */
93static linker_file_t linker_find_file_by_id(int _fileid);
94
95/* Metadata from the static kernel */
96SET_DECLARE(modmetadata_set, struct mod_metadata);
97
98MALLOC_DEFINE(M_LINKER, "linker", "kernel linker");
99
100linker_file_t linker_kernel_file;
101
102static struct sx kld_sx; /* kernel linker lock */
103
104/*
105 * Load counter used by clients to determine if a linker file has been
106 * re-loaded. This counter is incremented for each file load.
107 */
108static int loadcnt;
109
110static linker_class_list_t classes;
111static linker_file_list_t linker_files;
112static int next_file_id = 1;
113static int linker_no_more_classes = 0;
114
115#define LINKER_GET_NEXT_FILE_ID(a) do { \
116 linker_file_t lftmp; \
117 \
118 KLD_LOCK_ASSERT(); \
119retry: \
120 TAILQ_FOREACH(lftmp, &linker_files, link) { \
121 if (next_file_id == lftmp->id) { \
122 next_file_id++; \
123 goto retry; \
124 } \
125 } \
126 (a) = next_file_id; \
127} while(0)
128
129
130/* XXX wrong name; we're looking at version provision tags here, not modules */
131typedef TAILQ_HEAD(, modlist) modlisthead_t;
132struct modlist {
133 TAILQ_ENTRY(modlist) link; /* chain together all modules */
134 linker_file_t container;
135 const char *name;
136 int version;
137};
138typedef struct modlist *modlist_t;
139static modlisthead_t found_modules;
140
141static int linker_file_add_dependency(linker_file_t file,
142 linker_file_t dep);
143static caddr_t linker_file_lookup_symbol_internal(linker_file_t file,
144 const char* name, int deps);
145static int linker_load_module(const char *kldname,
146 const char *modname, struct linker_file *parent,
147 struct mod_depend *verinfo, struct linker_file **lfpp);
148static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo);
149
150static char *
151linker_strdup(const char *str)
152{
153 char *result;
154
155 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL)
156 strcpy(result, str);
157 return (result);
158}
159
160static void
161linker_init(void *arg)
162{
163
164 sx_init(&kld_sx, "kernel linker");
165 TAILQ_INIT(&classes);
166 TAILQ_INIT(&linker_files);
167}
168
169SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0);
170
171static void
172linker_stop_class_add(void *arg)
173{
174
175 linker_no_more_classes = 1;
176}
177
178SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL);
179
180int
181linker_add_class(linker_class_t lc)
182{
183
184 /*
185 * We disallow any class registration past SI_ORDER_ANY
186 * of SI_SUB_KLD. We bump the reference count to keep the
187 * ops from being freed.
188 */
189 if (linker_no_more_classes == 1)
190 return (EPERM);
191 kobj_class_compile((kobj_class_t) lc);
192 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */
193 TAILQ_INSERT_TAIL(&classes, lc, link);
194 return (0);
195}
196
197static void
198linker_file_sysinit(linker_file_t lf)
199{
200 struct sysinit **start, **stop, **sipp, **xipp, *save;
201
202 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
203 lf->filename));
204
205 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
206 return;
207 /*
208 * Perform a bubble sort of the system initialization objects by
209 * their subsystem (primary key) and order (secondary key).
210 *
211 * Since some things care about execution order, this is the operation
212 * which ensures continued function.
213 */
214 for (sipp = start; sipp < stop; sipp++) {
215 for (xipp = sipp + 1; xipp < stop; xipp++) {
216 if ((*sipp)->subsystem < (*xipp)->subsystem ||
217 ((*sipp)->subsystem == (*xipp)->subsystem &&
218 (*sipp)->order <= (*xipp)->order))
219 continue; /* skip */
220 save = *sipp;
221 *sipp = *xipp;
222 *xipp = save;
223 }
224 }
225
226 /*
227 * Traverse the (now) ordered list of system initialization tasks.
228 * Perform each task, and continue on to the next task.
229 */
230 mtx_lock(&Giant);
231 for (sipp = start; sipp < stop; sipp++) {
232 if ((*sipp)->subsystem == SI_SUB_DUMMY)
233 continue; /* skip dummy task(s) */
234
235 /* Call function */
236 (*((*sipp)->func)) ((*sipp)->udata);
237 }
238 mtx_unlock(&Giant);
239}
240
241static void
242linker_file_sysuninit(linker_file_t lf)
243{
244 struct sysinit **start, **stop, **sipp, **xipp, *save;
245
246 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n",
247 lf->filename));
248
249 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop,
250 NULL) != 0)
251 return;
252
253 /*
254 * Perform a reverse bubble sort of the system initialization objects
255 * by their subsystem (primary key) and order (secondary key).
256 *
257 * Since some things care about execution order, this is the operation
258 * which ensures continued function.
259 */
260 for (sipp = start; sipp < stop; sipp++) {
261 for (xipp = sipp + 1; xipp < stop; xipp++) {
262 if ((*sipp)->subsystem > (*xipp)->subsystem ||
263 ((*sipp)->subsystem == (*xipp)->subsystem &&
264 (*sipp)->order >= (*xipp)->order))
265 continue; /* skip */
266 save = *sipp;
267 *sipp = *xipp;
268 *xipp = save;
269 }
270 }
271
272 /*
273 * Traverse the (now) ordered list of system initialization tasks.
274 * Perform each task, and continue on to the next task.
275 */
276 mtx_lock(&Giant);
277 for (sipp = start; sipp < stop; sipp++) {
278 if ((*sipp)->subsystem == SI_SUB_DUMMY)
279 continue; /* skip dummy task(s) */
280
281 /* Call function */
282 (*((*sipp)->func)) ((*sipp)->udata);
283 }
284 mtx_unlock(&Giant);
285}
286
287static void
288linker_file_register_sysctls(linker_file_t lf)
289{
290 struct sysctl_oid **start, **stop, **oidp;
291
292 KLD_DPF(FILE,
293 ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
294 lf->filename));
295
296 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
297 return;
298
299 sysctl_lock();
300 for (oidp = start; oidp < stop; oidp++)
301 sysctl_register_oid(*oidp);
302 sysctl_unlock();
303}
304
305static void
306linker_file_unregister_sysctls(linker_file_t lf)
307{
308 struct sysctl_oid **start, **stop, **oidp;
309
310 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs"
311 " for %s\n", lf->filename));
312
313 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
314 return;
315
316 sysctl_lock();
317 for (oidp = start; oidp < stop; oidp++)
318 sysctl_unregister_oid(*oidp);
319 sysctl_unlock();
320}
321
322static int
323linker_file_register_modules(linker_file_t lf)
324{
325 struct mod_metadata **start, **stop, **mdp;
326 const moduledata_t *moddata;
327 int first_error, error;
328
329 KLD_DPF(FILE, ("linker_file_register_modules: registering modules"
330 " in %s\n", lf->filename));
331
332 if (linker_file_lookup_set(lf, "modmetadata_set", &start,
333 &stop, NULL) != 0) {
334 /*
335 * This fallback should be unnecessary, but if we get booted
336 * from boot2 instead of loader and we are missing our
337 * metadata then we have to try the best we can.
338 */
339 if (lf == linker_kernel_file) {
340 start = SET_BEGIN(modmetadata_set);
341 stop = SET_LIMIT(modmetadata_set);
342 } else
343 return (0);
344 }
345 first_error = 0;
346 for (mdp = start; mdp < stop; mdp++) {
347 if ((*mdp)->md_type != MDT_MODULE)
348 continue;
349 moddata = (*mdp)->md_data;
350 KLD_DPF(FILE, ("Registering module %s in %s\n",
351 moddata->name, lf->filename));
352 error = module_register(moddata, lf);
353 if (error) {
354 printf("Module %s failed to register: %d\n",
355 moddata->name, error);
356 if (first_error == 0)
357 first_error = error;
358 }
359 }
360 return (first_error);
361}
362
363static void
364linker_init_kernel_modules(void)
365{
366
367 linker_file_register_modules(linker_kernel_file);
368}
369
370SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules,
371 0);
372
373static int
374linker_load_file(const char *filename, linker_file_t *result)
375{
376 linker_class_t lc;
377 linker_file_t lf;
378 int foundfile, error;
379
380 /* Refuse to load modules if securelevel raised */
381 if (prison0.pr_securelevel > 0)
382 return (EPERM);
383
384 KLD_LOCK_ASSERT();
385 lf = linker_find_file_by_name(filename);
386 if (lf) {
387 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded,"
388 " incrementing refs\n", filename));
389 *result = lf;
390 lf->refs++;
391 return (0);
392 }
393 foundfile = 0;
394 error = 0;
395
396 /*
397 * We do not need to protect (lock) classes here because there is
398 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY)
399 * and there is no class deregistration mechanism at this time.
400 */
401 TAILQ_FOREACH(lc, &classes, link) {
402 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
403 filename));
404 error = LINKER_LOAD_FILE(lc, filename, &lf);
405 /*
406 * If we got something other than ENOENT, then it exists but
407 * we cannot load it for some other reason.
408 */
409 if (error != ENOENT)
410 foundfile = 1;
411 if (lf) {
412 error = linker_file_register_modules(lf);
413 if (error == EEXIST) {
414 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
415 return (error);
416 }
417 KLD_UNLOCK();
418 linker_file_register_sysctls(lf);
419 linker_file_sysinit(lf);
420 KLD_LOCK();
421 lf->flags |= LINKER_FILE_LINKED;
422 *result = lf;
423 return (0);
424 }
425 }
426 /*
427 * Less than ideal, but tells the user whether it failed to load or
428 * the module was not found.
429 */
430 if (foundfile) {
431
432 /*
433 * If the file type has not been recognized by the last try
434 * printout a message before to fail.
435 */
436 if (error == ENOSYS)
437 printf("linker_load_file: Unsupported file type\n");
438
439 /*
440 * Format not recognized or otherwise unloadable.
441 * When loading a module that is statically built into
442 * the kernel EEXIST percolates back up as the return
443 * value. Preserve this so that apps like sysinstall
444 * can recognize this special case and not post bogus
445 * dialog boxes.
446 */
447 if (error != EEXIST)
448 error = ENOEXEC;
449 } else
450 error = ENOENT; /* Nothing found */
451 return (error);
452}
453
454int
455linker_reference_module(const char *modname, struct mod_depend *verinfo,
456 linker_file_t *result)
457{
458 modlist_t mod;
459 int error;
460
461 KLD_LOCK();
462 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) {
463 *result = mod->container;
464 (*result)->refs++;
465 KLD_UNLOCK();
466 return (0);
467 }
468
469 error = linker_load_module(NULL, modname, NULL, verinfo, result);
470 KLD_UNLOCK();
471 return (error);
472}
473
474int
475linker_release_module(const char *modname, struct mod_depend *verinfo,
476 linker_file_t lf)
477{
478 modlist_t mod;
479 int error;
480
481 KLD_LOCK();
482 if (lf == NULL) {
483 KASSERT(modname != NULL,
484 ("linker_release_module: no file or name"));
485 mod = modlist_lookup2(modname, verinfo);
486 if (mod == NULL) {
487 KLD_UNLOCK();
488 return (ESRCH);
489 }
490 lf = mod->container;
491 } else
492 KASSERT(modname == NULL && verinfo == NULL,
493 ("linker_release_module: both file and name"));
494 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL);
495 KLD_UNLOCK();
496 return (error);
497}
498
499static linker_file_t
500linker_find_file_by_name(const char *filename)
501{
502 linker_file_t lf;
503 char *koname;
504
505 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
506 sprintf(koname, "%s.ko", filename);
507
508 KLD_LOCK_ASSERT();
509 TAILQ_FOREACH(lf, &linker_files, link) {
510 if (strcmp(lf->filename, koname) == 0)
511 break;
512 if (strcmp(lf->filename, filename) == 0)
513 break;
514 }
515 free(koname, M_LINKER);
516 return (lf);
517}
518
519static linker_file_t
520linker_find_file_by_id(int fileid)
521{
522 linker_file_t lf;
523
524 KLD_LOCK_ASSERT();
525 TAILQ_FOREACH(lf, &linker_files, link)
526 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED)
527 break;
528 return (lf);
529}
530
531int
532linker_file_foreach(linker_predicate_t *predicate, void *context)
533{
534 linker_file_t lf;
535 int retval = 0;
536
537 KLD_LOCK();
538 TAILQ_FOREACH(lf, &linker_files, link) {
539 retval = predicate(lf, context);
540 if (retval != 0)
541 break;
542 }
543 KLD_UNLOCK();
544 return (retval);
545}
546
547linker_file_t
548linker_make_file(const char *pathname, linker_class_t lc)
549{
550 linker_file_t lf;
551 const char *filename;
552
553 KLD_LOCK_ASSERT();
554 filename = linker_basename(pathname);
555
556 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname));
557 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK);
558 if (lf == NULL)
559 return (NULL);
560 lf->refs = 1;
561 lf->userrefs = 0;
562 lf->flags = 0;
563 lf->filename = linker_strdup(filename);
564 lf->pathname = linker_strdup(pathname);
565 LINKER_GET_NEXT_FILE_ID(lf->id);
566 lf->ndeps = 0;
567 lf->deps = NULL;
568 lf->loadcnt = ++loadcnt;
569 lf->sdt_probes = NULL;
570 lf->sdt_nprobes = 0;
571 STAILQ_INIT(&lf->common);
572 TAILQ_INIT(&lf->modules);
573 TAILQ_INSERT_TAIL(&linker_files, lf, link);
574 return (lf);
575}
576
577int
578linker_file_unload(linker_file_t file, int flags)
579{
580 module_t mod, next;
581 modlist_t ml, nextml;
582 struct common_symbol *cp;
583 int error, i;
584
585 /* Refuse to unload modules if securelevel raised. */
586 if (prison0.pr_securelevel > 0)
587 return (EPERM);
588
589 KLD_LOCK_ASSERT();
590 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
591
592 /* Easy case of just dropping a reference. */
593 if (file->refs > 1) {
594 file->refs--;
595 return (0);
596 }
597
598 KLD_DPF(FILE, ("linker_file_unload: file is unloading,"
599 " informing modules\n"));
600
601 /*
602 * Quiesce all the modules to give them a chance to veto the unload.
603 */
604 MOD_SLOCK;
605 for (mod = TAILQ_FIRST(&file->modules); mod;
606 mod = module_getfnext(mod)) {
607
608 error = module_quiesce(mod);
609 if (error != 0 && flags != LINKER_UNLOAD_FORCE) {
610 KLD_DPF(FILE, ("linker_file_unload: module %s"
611 " vetoed unload\n", module_getname(mod)));
612 /*
613 * XXX: Do we need to tell all the quiesced modules
614 * that they can resume work now via a new module
615 * event?
616 */
617 MOD_SUNLOCK;
618 return (error);
619 }
620 }
621 MOD_SUNLOCK;
622
623 /*
624 * Inform any modules associated with this file that they are
625 * being be unloaded.
626 */
627 MOD_XLOCK;
628 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
629 next = module_getfnext(mod);
630 MOD_XUNLOCK;
631
632 /*
633 * Give the module a chance to veto the unload.
634 */
635 if ((error = module_unload(mod)) != 0) {
636 KLD_DPF(FILE, ("linker_file_unload: module %s"
637 " failed unload\n", module_getname(mod)));
638 return (error);
639 }
640 MOD_XLOCK;
641 module_release(mod);
642 }
643 MOD_XUNLOCK;
644
645 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) {
646 if (ml->container == file) {
647 TAILQ_REMOVE(&found_modules, ml, link);
648 free(ml, M_LINKER);
649 }
650 }
651
652 /*
653 * Don't try to run SYSUNINITs if we are unloaded due to a
654 * link error.
655 */
656 if (file->flags & LINKER_FILE_LINKED) {
657 file->flags &= ~LINKER_FILE_LINKED;
658 KLD_UNLOCK();
659 linker_file_sysuninit(file);
660 linker_file_unregister_sysctls(file);
661 KLD_LOCK();
662 }
663 TAILQ_REMOVE(&linker_files, file, link);
664
665 if (file->deps) {
666 for (i = 0; i < file->ndeps; i++)
667 linker_file_unload(file->deps[i], flags);
668 free(file->deps, M_LINKER);
669 file->deps = NULL;
670 }
671 while ((cp = STAILQ_FIRST(&file->common)) != NULL) {
672 STAILQ_REMOVE_HEAD(&file->common, link);
673 free(cp, M_LINKER);
674 }
675
676 LINKER_UNLOAD(file);
677 if (file->filename) {
678 free(file->filename, M_LINKER);
679 file->filename = NULL;
680 }
681 if (file->pathname) {
682 free(file->pathname, M_LINKER);
683 file->pathname = NULL;
684 }
685 kobj_delete((kobj_t) file, M_LINKER);
686 return (0);
687}
688
689int
690linker_ctf_get(linker_file_t file, linker_ctf_t *lc)
691{
692 return (LINKER_CTF_GET(file, lc));
693}
694
695static int
696linker_file_add_dependency(linker_file_t file, linker_file_t dep)
697{
698 linker_file_t *newdeps;
699
700 KLD_LOCK_ASSERT();
701 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *),
702 M_LINKER, M_WAITOK | M_ZERO);
703 if (newdeps == NULL)
704 return (ENOMEM);
705
706 if (file->deps) {
707 bcopy(file->deps, newdeps,
708 file->ndeps * sizeof(linker_file_t *));
709 free(file->deps, M_LINKER);
710 }
711 file->deps = newdeps;
712 file->deps[file->ndeps] = dep;
713 file->ndeps++;
714 KLD_DPF(FILE, ("linker_file_add_dependency:"
715 " adding %s as dependency for %s\n",
716 dep->filename, file->filename));
717 return (0);
718}
719
720/*
721 * Locate a linker set and its contents. This is a helper function to avoid
722 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **.
723 * This function is used in this file so we can avoid having lots of (void **)
724 * casts.
725 */
726int
727linker_file_lookup_set(linker_file_t file, const char *name,
728 void *firstp, void *lastp, int *countp)
729{
730 int error, locked;
731
732 locked = KLD_LOCKED();
733 if (!locked)
734 KLD_LOCK();
735 error = LINKER_LOOKUP_SET(file, name, firstp, lastp, countp);
736 if (!locked)
737 KLD_UNLOCK();
738 return (error);
739}
740
741/*
742 * List all functions in a file.
743 */
744int
745linker_file_function_listall(linker_file_t lf,
746 linker_function_nameval_callback_t callback_func, void *arg)
747{
748 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg));
749}
750
751caddr_t
752linker_file_lookup_symbol(linker_file_t file, const char *name, int deps)
753{
754 caddr_t sym;
755 int locked;
756
757 locked = KLD_LOCKED();
758 if (!locked)
759 KLD_LOCK();
760 sym = linker_file_lookup_symbol_internal(file, name, deps);
761 if (!locked)
762 KLD_UNLOCK();
763 return (sym);
764}
765
766static caddr_t
767linker_file_lookup_symbol_internal(linker_file_t file, const char *name,
768 int deps)
769{
770 c_linker_sym_t sym;
771 linker_symval_t symval;
772 caddr_t address;
773 size_t common_size = 0;
774 int i;
775
776 KLD_LOCK_ASSERT();
777 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n",
778 file, name, deps));
779
780 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
781 LINKER_SYMBOL_VALUES(file, sym, &symval);
782 if (symval.value == 0)
783 /*
784 * For commons, first look them up in the
785 * dependencies and only allocate space if not found
786 * there.
787 */
788 common_size = symval.size;
789 else {
790 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol"
791 ".value=%p\n", symval.value));
792 return (symval.value);
793 }
794 }
795 if (deps) {
796 for (i = 0; i < file->ndeps; i++) {
797 address = linker_file_lookup_symbol_internal(
798 file->deps[i], name, 0);
799 if (address) {
800 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
801 " deps value=%p\n", address));
802 return (address);
803 }
804 }
805 }
806 if (common_size > 0) {
807 /*
808 * This is a common symbol which was not found in the
809 * dependencies. We maintain a simple common symbol table in
810 * the file object.
811 */
812 struct common_symbol *cp;
813
814 STAILQ_FOREACH(cp, &file->common, link) {
815 if (strcmp(cp->name, name) == 0) {
816 KLD_DPF(SYM, ("linker_file_lookup_symbol:"
817 " old common value=%p\n", cp->address));
818 return (cp->address);
819 }
820 }
821 /*
822 * Round the symbol size up to align.
823 */
824 common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
825 cp = malloc(sizeof(struct common_symbol)
826 + common_size + strlen(name) + 1, M_LINKER,
827 M_WAITOK | M_ZERO);
828 cp->address = (caddr_t)(cp + 1);
829 cp->name = cp->address + common_size;
830 strcpy(cp->name, name);
831 bzero(cp->address, common_size);
832 STAILQ_INSERT_TAIL(&file->common, cp, link);
833
834 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common"
835 " value=%p\n", cp->address));
836 return (cp->address);
837 }
838 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
839 return (0);
840}
841
842/*
843 * Both DDB and stack(9) rely on the kernel linker to provide forward and
844 * backward lookup of symbols. However, DDB and sometimes stack(9) need to
845 * do this in a lockfree manner. We provide a set of internal helper
846 * routines to perform these operations without locks, and then wrappers that
847 * optionally lock.
848 *
849 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB.
850 */
851#ifdef DDB
852static int
853linker_debug_lookup(const char *symstr, c_linker_sym_t *sym)
854{
855 linker_file_t lf;
856
857 TAILQ_FOREACH(lf, &linker_files, link) {
858 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0)
859 return (0);
860 }
861 return (ENOENT);
862}
863#endif
864
865static int
866linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
867{
868 linker_file_t lf;
869 c_linker_sym_t best, es;
870 u_long diff, bestdiff, off;
871
872 best = 0;
873 off = (uintptr_t)value;
874 bestdiff = off;
875 TAILQ_FOREACH(lf, &linker_files, link) {
876 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
877 continue;
878 if (es != 0 && diff < bestdiff) {
879 best = es;
880 bestdiff = diff;
881 }
882 if (bestdiff == 0)
883 break;
884 }
885 if (best) {
886 *sym = best;
887 *diffp = bestdiff;
888 return (0);
889 } else {
890 *sym = 0;
891 *diffp = off;
892 return (ENOENT);
893 }
894}
895
896static int
897linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
898{
899 linker_file_t lf;
900
901 TAILQ_FOREACH(lf, &linker_files, link) {
902 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0)
903 return (0);
904 }
905 return (ENOENT);
906}
907
908static int
909linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen,
910 long *offset)
911{
912 linker_symval_t symval;
913 c_linker_sym_t sym;
914 int error;
915
916 *offset = 0;
917 error = linker_debug_search_symbol(value, &sym, offset);
918 if (error)
919 return (error);
920 error = linker_debug_symbol_values(sym, &symval);
921 if (error)
922 return (error);
923 strlcpy(buf, symval.name, buflen);
924 return (0);
925}
926
927/*
928 * DDB Helpers. DDB has to look across multiple files with their own symbol
929 * tables and string tables.
930 *
931 * Note that we do not obey list locking protocols here. We really don't need
932 * DDB to hang because somebody's got the lock held. We'll take the chance
933 * that the files list is inconsistant instead.
934 */
935#ifdef DDB
936int
937linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
938{
939
940 return (linker_debug_lookup(symstr, sym));
941}
942#endif
943
944int
945linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
946{
947
948 return (linker_debug_search_symbol(value, sym, diffp));
949}
950
951int
952linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
953{
954
955 return (linker_debug_symbol_values(sym, symval));
956}
957
958int
959linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen,
960 long *offset)
961{
962
963 return (linker_debug_search_symbol_name(value, buf, buflen, offset));
964}
965
966/*
967 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do
968 * obey locking protocols, and offer a significantly less complex interface.
969 */
970int
971linker_search_symbol_name(caddr_t value, char *buf, u_int buflen,
972 long *offset)
973{
974 int error;
975
976 KLD_LOCK();
977 error = linker_debug_search_symbol_name(value, buf, buflen, offset);
978 KLD_UNLOCK();
979 return (error);
980}
981
982/*
983 * Syscalls.
984 */
985int
986kern_kldload(struct thread *td, const char *file, int *fileid)
987{
988#ifdef HWPMC_HOOKS
989 struct pmckern_map_in pkm;
990#endif
991 const char *kldname, *modname;
992 linker_file_t lf;
993 int error;
994
995 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
996 return (error);
997
998 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0)
999 return (error);
1000
1001 /*
1002 * It is possible that kldloaded module will attach a new ifnet,
1003 * so vnet context must be set when this ocurs.
1004 */
1005 CURVNET_SET(TD_TO_VNET(td));
1006
1007 /*
1008 * If file does not contain a qualified name or any dot in it
1009 * (kldname.ko, or kldname.ver.ko) treat it as an interface
1010 * name.
1011 */
1012 if (index(file, '/') || index(file, '.')) {
1013 kldname = file;
1014 modname = NULL;
1015 } else {
1016 kldname = NULL;
1017 modname = file;
1018 }
1019
1020 KLD_LOCK();
1021 error = linker_load_module(kldname, modname, NULL, NULL, &lf);
1022 if (error)
1023 goto unlock;
1024#ifdef HWPMC_HOOKS
1025 pkm.pm_file = lf->filename;
1026 pkm.pm_address = (uintptr_t) lf->address;
1027 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm);
1028#endif
1029 lf->userrefs++;
1030 if (fileid != NULL)
1031 *fileid = lf->id;
1032unlock:
1033 KLD_UNLOCK();
1034 CURVNET_RESTORE();
1035 return (error);
1036}
1037
1038int
1039kldload(struct thread *td, struct kldload_args *uap)
1040{
1041 char *pathname = NULL;
1042 int error, fileid;
1043
1044 td->td_retval[0] = -1;
1045
1046 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1047 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL);
1048 if (error == 0) {
1049 error = kern_kldload(td, pathname, &fileid);
1050 if (error == 0)
1051 td->td_retval[0] = fileid;
1052 }
1053 free(pathname, M_TEMP);
1054 return (error);
1055}
1056
1057int
1058kern_kldunload(struct thread *td, int fileid, int flags)
1059{
1060#ifdef HWPMC_HOOKS
1061 struct pmckern_map_out pkm;
1062#endif
1063 linker_file_t lf;
1064 int error = 0;
1065
1066 if ((error = securelevel_gt(td->td_ucred, 0)) != 0)
1067 return (error);
1068
1069 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0)
1070 return (error);
1071
1072 CURVNET_SET(TD_TO_VNET(td));
1073 KLD_LOCK();
1074 lf = linker_find_file_by_id(fileid);
1075 if (lf) {
1076 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
1077
1078 /* Check if there are DTrace probes enabled on this file. */
1079 if (lf->nenabled > 0) {
1080 printf("kldunload: attempt to unload file that has"
1081 " DTrace probes enabled\n");
1082 error = EBUSY;
1083 } else if (lf->userrefs == 0) {
1084 /*
1085 * XXX: maybe LINKER_UNLOAD_FORCE should override ?
1086 */
1087 printf("kldunload: attempt to unload file that was"
1088 " loaded by the kernel\n");
1089 error = EBUSY;
1090 } else {
1091#ifdef HWPMC_HOOKS
1092 /* Save data needed by hwpmc(4) before unloading. */
1093 pkm.pm_address = (uintptr_t) lf->address;
1094 pkm.pm_size = lf->size;
1095#endif
1096 lf->userrefs--;
1097 error = linker_file_unload(lf, flags);
1098 if (error)
1099 lf->userrefs++;
1100 }
1101 } else
1102 error = ENOENT;
1103
1104#ifdef HWPMC_HOOKS
1105 if (error == 0)
1106 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm);
1107#endif
1108 KLD_UNLOCK();
1109 CURVNET_RESTORE();
1110 return (error);
1111}
1112
1113int
1114kldunload(struct thread *td, struct kldunload_args *uap)
1115{
1116
1117 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL));
1118}
1119
1120int
1121kldunloadf(struct thread *td, struct kldunloadf_args *uap)
1122{
1123
1124 if (uap->flags != LINKER_UNLOAD_NORMAL &&
1125 uap->flags != LINKER_UNLOAD_FORCE)
1126 return (EINVAL);
1127 return (kern_kldunload(td, uap->fileid, uap->flags));
1128}
1129
1130int
1131kldfind(struct thread *td, struct kldfind_args *uap)
1132{
1133 char *pathname;
1134 const char *filename;
1135 linker_file_t lf;
1136 int error;
1137
1138#ifdef MAC
1139 error = mac_kld_check_stat(td->td_ucred);
1140 if (error)
1141 return (error);
1142#endif
1143
1144 td->td_retval[0] = -1;
1145
1146 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1147 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0)
1148 goto out;
1149
1150 filename = linker_basename(pathname);
1151 KLD_LOCK();
1152 lf = linker_find_file_by_name(filename);
1153 if (lf)
1154 td->td_retval[0] = lf->id;
1155 else
1156 error = ENOENT;
1157 KLD_UNLOCK();
1158out:
1159 free(pathname, M_TEMP);
1160 return (error);
1161}
1162
1163int
1164kldnext(struct thread *td, struct kldnext_args *uap)
1165{
1166 linker_file_t lf;
1167 int error = 0;
1168
1169#ifdef MAC
1170 error = mac_kld_check_stat(td->td_ucred);
1171 if (error)
1172 return (error);
1173#endif
1174
1175 KLD_LOCK();
1176 if (uap->fileid == 0)
1177 lf = TAILQ_FIRST(&linker_files);
1178 else {
1179 lf = linker_find_file_by_id(uap->fileid);
1180 if (lf == NULL) {
1181 error = ENOENT;
1182 goto out;
1183 }
1184 lf = TAILQ_NEXT(lf, link);
1185 }
1186
1187 /* Skip partially loaded files. */
1188 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED))
1189 lf = TAILQ_NEXT(lf, link);
1190
1191 if (lf)
1192 td->td_retval[0] = lf->id;
1193 else
1194 td->td_retval[0] = 0;
1195out:
1196 KLD_UNLOCK();
1197 return (error);
1198}
1199
1200int
1201kldstat(struct thread *td, struct kldstat_args *uap)
1202{
1203 struct kld_file_stat stat;
1204 linker_file_t lf;
1205 int error, namelen, version, version_num;
1206
1207 /*
1208 * Check the version of the user's structure.
1209 */
1210 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) != 0)
1211 return (error);
1212 if (version == sizeof(struct kld_file_stat_1))
1213 version_num = 1;
1214 else if (version == sizeof(struct kld_file_stat))
1215 version_num = 2;
1216 else
1217 return (EINVAL);
1218
1219#ifdef MAC
1220 error = mac_kld_check_stat(td->td_ucred);
1221 if (error)
1222 return (error);
1223#endif
1224
1225 KLD_LOCK();
1226 lf = linker_find_file_by_id(uap->fileid);
1227 if (lf == NULL) {
1228 KLD_UNLOCK();
1229 return (ENOENT);
1230 }
1231
1232 /* Version 1 fields: */
1233 namelen = strlen(lf->filename) + 1;
1234 if (namelen > MAXPATHLEN)
1235 namelen = MAXPATHLEN;
1236 bcopy(lf->filename, &stat.name[0], namelen);
1237 stat.refs = lf->refs;
1238 stat.id = lf->id;
1239 stat.address = lf->address;
1240 stat.size = lf->size;
1241 if (version_num > 1) {
1242 /* Version 2 fields: */
1243 namelen = strlen(lf->pathname) + 1;
1244 if (namelen > MAXPATHLEN)
1245 namelen = MAXPATHLEN;
1246 bcopy(lf->pathname, &stat.pathname[0], namelen);
1247 }
1248 KLD_UNLOCK();
1249
1250 td->td_retval[0] = 0;
1251
1252 return (copyout(&stat, uap->stat, version));
1253}
1254
1255int
1256kldfirstmod(struct thread *td, struct kldfirstmod_args *uap)
1257{
1258 linker_file_t lf;
1259 module_t mp;
1260 int error = 0;
1261
1262#ifdef MAC
1263 error = mac_kld_check_stat(td->td_ucred);
1264 if (error)
1265 return (error);
1266#endif
1267
1268 KLD_LOCK();
1269 lf = linker_find_file_by_id(uap->fileid);
1270 if (lf) {
1271 MOD_SLOCK;
1272 mp = TAILQ_FIRST(&lf->modules);
1273 if (mp != NULL)
1274 td->td_retval[0] = module_getid(mp);
1275 else
1276 td->td_retval[0] = 0;
1277 MOD_SUNLOCK;
1278 } else
1279 error = ENOENT;
1280 KLD_UNLOCK();
1281 return (error);
1282}
1283
1284int
1285kldsym(struct thread *td, struct kldsym_args *uap)
1286{
1287 char *symstr = NULL;
1288 c_linker_sym_t sym;
1289 linker_symval_t symval;
1290 linker_file_t lf;
1291 struct kld_sym_lookup lookup;
1292 int error = 0;
1293
1294#ifdef MAC
1295 error = mac_kld_check_stat(td->td_ucred);
1296 if (error)
1297 return (error);
1298#endif
1299
1300 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0)
1301 return (error);
1302 if (lookup.version != sizeof(lookup) ||
1303 uap->cmd != KLDSYM_LOOKUP)
1304 return (EINVAL);
1305 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1306 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
1307 goto out;
1308 KLD_LOCK();
1309 if (uap->fileid != 0) {
1310 lf = linker_find_file_by_id(uap->fileid);
1311 if (lf == NULL)
1312 error = ENOENT;
1313 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1314 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1315 lookup.symvalue = (uintptr_t) symval.value;
1316 lookup.symsize = symval.size;
1317 error = copyout(&lookup, uap->data, sizeof(lookup));
1318 } else
1319 error = ENOENT;
1320 } else {
1321 TAILQ_FOREACH(lf, &linker_files, link) {
1322 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
1323 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
1324 lookup.symvalue = (uintptr_t)symval.value;
1325 lookup.symsize = symval.size;
1326 error = copyout(&lookup, uap->data,
1327 sizeof(lookup));
1328 break;
1329 }
1330 }
1331 if (lf == NULL)
1332 error = ENOENT;
1333 }
1334 KLD_UNLOCK();
1335out:
1336 free(symstr, M_TEMP);
1337 return (error);
1338}
1339
1340/*
1341 * Preloaded module support
1342 */
1343
1344static modlist_t
1345modlist_lookup(const char *name, int ver)
1346{
1347 modlist_t mod;
1348
1349 TAILQ_FOREACH(mod, &found_modules, link) {
1350 if (strcmp(mod->name, name) == 0 &&
1351 (ver == 0 || mod->version == ver))
1352 return (mod);
1353 }
1354 return (NULL);
1355}
1356
1357static modlist_t
1358modlist_lookup2(const char *name, struct mod_depend *verinfo)
1359{
1360 modlist_t mod, bestmod;
1361 int ver;
1362
1363 if (verinfo == NULL)
1364 return (modlist_lookup(name, 0));
1365 bestmod = NULL;
1366 TAILQ_FOREACH(mod, &found_modules, link) {
1367 if (strcmp(mod->name, name) != 0)
1368 continue;
1369 ver = mod->version;
1370 if (ver == verinfo->md_ver_preferred)
1371 return (mod);
1372 if (ver >= verinfo->md_ver_minimum &&
1373 ver <= verinfo->md_ver_maximum &&
1374 (bestmod == NULL || ver > bestmod->version))
1375 bestmod = mod;
1376 }
1377 return (bestmod);
1378}
1379
1380static modlist_t
1381modlist_newmodule(const char *modname, int version, linker_file_t container)
1382{
1383 modlist_t mod;
1384
1385 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO);
1386 if (mod == NULL)
1387 panic("no memory for module list");
1388 mod->container = container;
1389 mod->name = modname;
1390 mod->version = version;
1391 TAILQ_INSERT_TAIL(&found_modules, mod, link);
1392 return (mod);
1393}
1394
1395static void
1396linker_addmodules(linker_file_t lf, struct mod_metadata **start,
1397 struct mod_metadata **stop, int preload)
1398{
1399 struct mod_metadata *mp, **mdp;
1400 const char *modname;
1401 int ver;
1402
1403 for (mdp = start; mdp < stop; mdp++) {
1404 mp = *mdp;
1405 if (mp->md_type != MDT_VERSION)
1406 continue;
1407 modname = mp->md_cval;
1408 ver = ((struct mod_version *)mp->md_data)->mv_version;
1409 if (modlist_lookup(modname, ver) != NULL) {
1410 printf("module %s already present!\n", modname);
1411 /* XXX what can we do? this is a build error. :-( */
1412 continue;
1413 }
1414 modlist_newmodule(modname, ver, lf);
1415 }
1416}
1417
1418static void
1419linker_preload(void *arg)
1420{
1421 caddr_t modptr;
1422 const char *modname, *nmodname;
1423 char *modtype;
1424 linker_file_t lf, nlf;
1425 linker_class_t lc;
1426 int error;
1427 linker_file_list_t loaded_files;
1428 linker_file_list_t depended_files;
1429 struct mod_metadata *mp, *nmp;
1430 struct mod_metadata **start, **stop, **mdp, **nmdp;
1431 struct mod_depend *verinfo;
1432 int nver;
1433 int resolves;
1434 modlist_t mod;
1435 struct sysinit **si_start, **si_stop;
1436
1437 TAILQ_INIT(&loaded_files);
1438 TAILQ_INIT(&depended_files);
1439 TAILQ_INIT(&found_modules);
1440 error = 0;
1441
1442 modptr = NULL;
1443 while ((modptr = preload_search_next_name(modptr)) != NULL) {
1444 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
1445 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
1446 if (modname == NULL) {
1447 printf("Preloaded module at %p does not have a"
1448 " name!\n", modptr);
1449 continue;
1450 }
1451 if (modtype == NULL) {
1452 printf("Preloaded module at %p does not have a type!\n",
1453 modptr);
1454 continue;
1455 }
1456 if (bootverbose)
1457 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname,
1458 modptr);
1459 lf = NULL;
1460 TAILQ_FOREACH(lc, &classes, link) {
1461 error = LINKER_LINK_PRELOAD(lc, modname, &lf);
1462 if (!error)
1463 break;
1464 lf = NULL;
1465 }
1466 if (lf)
1467 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
1468 }
1469
1470 /*
1471 * First get a list of stuff in the kernel.
1472 */
1473 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start,
1474 &stop, NULL) == 0)
1475 linker_addmodules(linker_kernel_file, start, stop, 1);
1476
1477 /*
1478 * This is a once-off kinky bubble sort to resolve relocation
1479 * dependency requirements.
1480 */
1481restart:
1482 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1483 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1484 &stop, NULL);
1485 /*
1486 * First, look to see if we would successfully link with this
1487 * stuff.
1488 */
1489 resolves = 1; /* unless we know otherwise */
1490 if (!error) {
1491 for (mdp = start; mdp < stop; mdp++) {
1492 mp = *mdp;
1493 if (mp->md_type != MDT_DEPEND)
1494 continue;
1495 modname = mp->md_cval;
1496 verinfo = mp->md_data;
1497 for (nmdp = start; nmdp < stop; nmdp++) {
1498 nmp = *nmdp;
1499 if (nmp->md_type != MDT_VERSION)
1500 continue;
1501 nmodname = nmp->md_cval;
1502 if (strcmp(modname, nmodname) == 0)
1503 break;
1504 }
1505 if (nmdp < stop) /* it's a self reference */
1506 continue;
1507
1508 /*
1509 * ok, the module isn't here yet, we
1510 * are not finished
1511 */
1512 if (modlist_lookup2(modname, verinfo) == NULL)
1513 resolves = 0;
1514 }
1515 }
1516 /*
1517 * OK, if we found our modules, we can link. So, "provide"
1518 * the modules inside and add it to the end of the link order
1519 * list.
1520 */
1521 if (resolves) {
1522 if (!error) {
1523 for (mdp = start; mdp < stop; mdp++) {
1524 mp = *mdp;
1525 if (mp->md_type != MDT_VERSION)
1526 continue;
1527 modname = mp->md_cval;
1528 nver = ((struct mod_version *)
1529 mp->md_data)->mv_version;
1530 if (modlist_lookup(modname,
1531 nver) != NULL) {
1532 printf("module %s already"
1533 " present!\n", modname);
1534 TAILQ_REMOVE(&loaded_files,
1535 lf, loaded);
1536 linker_file_unload(lf,
1537 LINKER_UNLOAD_FORCE);
1538 /* we changed tailq next ptr */
1539 goto restart;
1540 }
1541 modlist_newmodule(modname, nver, lf);
1542 }
1543 }
1544 TAILQ_REMOVE(&loaded_files, lf, loaded);
1545 TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
1546 /*
1547 * Since we provided modules, we need to restart the
1548 * sort so that the previous files that depend on us
1549 * have a chance. Also, we've busted the tailq next
1550 * pointer with the REMOVE.
1551 */
1552 goto restart;
1553 }
1554 }
1555
1556 /*
1557 * At this point, we check to see what could not be resolved..
1558 */
1559 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) {
1560 TAILQ_REMOVE(&loaded_files, lf, loaded);
1561 printf("KLD file %s is missing dependencies\n", lf->filename);
1562 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1563 }
1564
1565 /*
1566 * We made it. Finish off the linking in the order we determined.
1567 */
1568 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) {
1569 if (linker_kernel_file) {
1570 linker_kernel_file->refs++;
1571 error = linker_file_add_dependency(lf,
1572 linker_kernel_file);
1573 if (error)
1574 panic("cannot add dependency");
1575 }
1576 lf->userrefs++; /* so we can (try to) kldunload it */
1577 error = linker_file_lookup_set(lf, MDT_SETNAME, &start,
1578 &stop, NULL);
1579 if (!error) {
1580 for (mdp = start; mdp < stop; mdp++) {
1581 mp = *mdp;
1582 if (mp->md_type != MDT_DEPEND)
1583 continue;
1584 modname = mp->md_cval;
1585 verinfo = mp->md_data;
1586 mod = modlist_lookup2(modname, verinfo);
1587 if (mod == NULL) {
1588 printf("KLD file %s - cannot find "
1589 "dependency \"%s\"\n",
1590 lf->filename, modname);
1591 goto fail;
1592 }
1593 /* Don't count self-dependencies */
1594 if (lf == mod->container)
1595 continue;
1596 mod->container->refs++;
1597 error = linker_file_add_dependency(lf,
1598 mod->container);
1599 if (error)
1600 panic("cannot add dependency");
1601 }
1602 }
1603 /*
1604 * Now do relocation etc using the symbol search paths
1605 * established by the dependencies
1606 */
1607 error = LINKER_LINK_PRELOAD_FINISH(lf);
1608 if (error) {
1609 printf("KLD file %s - could not finalize loading\n",
1610 lf->filename);
1611 goto fail;
1612 }
1613 linker_file_register_modules(lf);
1614 if (linker_file_lookup_set(lf, "sysinit_set", &si_start,
1615 &si_stop, NULL) == 0)
1616 sysinit_add(si_start, si_stop);
1617 linker_file_register_sysctls(lf);
1618 lf->flags |= LINKER_FILE_LINKED;
1619 continue;
1620fail:
1621 TAILQ_REMOVE(&depended_files, lf, loaded);
1622 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1623 }
1624 /* woohoo! we made it! */
1625}
1626
1627SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0);
1628
1629/*
1630 * Search for a not-loaded module by name.
1631 *
1632 * Modules may be found in the following locations:
1633 *
1634 * - preloaded (result is just the module name) - on disk (result is full path
1635 * to module)
1636 *
1637 * If the module name is qualified in any way (contains path, etc.) the we
1638 * simply return a copy of it.
1639 *
1640 * The search path can be manipulated via sysctl. Note that we use the ';'
1641 * character as a separator to be consistent with the bootloader.
1642 */
1643
1644static char linker_hintfile[] = "linker.hints";
1645static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules";
1646
1647SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path,
1648 sizeof(linker_path), "module load search path");
1649
1650TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
1651
1652static char *linker_ext_list[] = {
1653 "",
1654 ".ko",
1655 NULL
1656};
1657
1658/*
1659 * Check if file actually exists either with or without extension listed in
1660 * the linker_ext_list. (probably should be generic for the rest of the
1661 * kernel)
1662 */
1663static char *
1664linker_lookup_file(const char *path, int pathlen, const char *name,
1665 int namelen, struct vattr *vap)
1666{
1667 struct nameidata nd;
1668 struct thread *td = curthread; /* XXX */
1669 char *result, **cpp, *sep;
1670 int error, len, extlen, reclen, flags, vfslocked;
1671 enum vtype type;
1672
1673 extlen = 0;
1674 for (cpp = linker_ext_list; *cpp; cpp++) {
1675 len = strlen(*cpp);
1676 if (len > extlen)
1677 extlen = len;
1678 }
1679 extlen++; /* trailing '\0' */
1680 sep = (path[pathlen - 1] != '/') ? "/" : "";
1681
1682 reclen = pathlen + strlen(sep) + namelen + extlen + 1;
1683 result = malloc(reclen, M_LINKER, M_WAITOK);
1684 for (cpp = linker_ext_list; *cpp; cpp++) {
1685 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep,
1686 namelen, name, *cpp);
1687 /*
1688 * Attempt to open the file, and return the path if
1689 * we succeed and it's a regular file.
1690 */
1691 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, result, td);
1692 flags = FREAD;
1693 error = vn_open(&nd, &flags, 0, NULL);
1694 if (error == 0) {
1695 vfslocked = NDHASGIANT(&nd);
1696 NDFREE(&nd, NDF_ONLY_PNBUF);
1697 type = nd.ni_vp->v_type;
1698 if (vap)
1699 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred);
1700 VOP_UNLOCK(nd.ni_vp, 0);
1701 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
1702 VFS_UNLOCK_GIANT(vfslocked);
1703 if (type == VREG)
1704 return (result);
1705 }
1706 }
1707 free(result, M_LINKER);
1708 return (NULL);
1709}
1710
1711#define INT_ALIGN(base, ptr) ptr = \
1712 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1))
1713
1714/*
1715 * Lookup KLD which contains requested module in the "linker.hints" file. If
1716 * version specification is available, then try to find the best KLD.
1717 * Otherwise just find the latest one.
1718 */
1719static char *
1720linker_hints_lookup(const char *path, int pathlen, const char *modname,
1721 int modnamelen, struct mod_depend *verinfo)
1722{
1723 struct thread *td = curthread; /* XXX */
1724 struct ucred *cred = td ? td->td_ucred : NULL;
1725 struct nameidata nd;
1726 struct vattr vattr, mattr;
1727 u_char *hints = NULL;
1728 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep;
1729 int error, ival, bestver, *intp, reclen, found, flags, clen, blen;
1730 int vfslocked = 0;
1731
1732 result = NULL;
1733 bestver = found = 0;
1734
1735 sep = (path[pathlen - 1] != '/') ? "/" : "";
1736 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen +
1737 strlen(sep) + 1;
1738 pathbuf = malloc(reclen, M_LINKER, M_WAITOK);
1739 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep,
1740 linker_hintfile);
1741
1742 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, pathbuf, td);
1743 flags = FREAD;
1744 error = vn_open(&nd, &flags, 0, NULL);
1745 if (error)
1746 goto bad;
1747 vfslocked = NDHASGIANT(&nd);
1748 NDFREE(&nd, NDF_ONLY_PNBUF);
1749 if (nd.ni_vp->v_type != VREG)
1750 goto bad;
1751 best = cp = NULL;
1752 error = VOP_GETATTR(nd.ni_vp, &vattr, cred);
1753 if (error)
1754 goto bad;
1755 /*
1756 * XXX: we need to limit this number to some reasonable value
1757 */
1758 if (vattr.va_size > 100 * 1024) {
1759 printf("hints file too large %ld\n", (long)vattr.va_size);
1760 goto bad;
1761 }
1762 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK);
1763 if (hints == NULL)
1764 goto bad;
1765 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0,
1766 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td);
1767 if (error)
1768 goto bad;
1769 VOP_UNLOCK(nd.ni_vp, 0);
1770 vn_close(nd.ni_vp, FREAD, cred, td);
1771 VFS_UNLOCK_GIANT(vfslocked);
1772 nd.ni_vp = NULL;
1773 if (reclen != 0) {
1774 printf("can't read %d\n", reclen);
1775 goto bad;
1776 }
1777 intp = (int *)hints;
1778 ival = *intp++;
1779 if (ival != LINKER_HINTS_VERSION) {
1780 printf("hints file version mismatch %d\n", ival);
1781 goto bad;
1782 }
1783 bufend = hints + vattr.va_size;
1784 recptr = (u_char *)intp;
1785 clen = blen = 0;
1786 while (recptr < bufend && !found) {
1787 intp = (int *)recptr;
1788 reclen = *intp++;
1789 ival = *intp++;
1790 cp = (char *)intp;
1791 switch (ival) {
1792 case MDT_VERSION:
1793 clen = *cp++;
1794 if (clen != modnamelen || bcmp(cp, modname, clen) != 0)
1795 break;
1796 cp += clen;
1797 INT_ALIGN(hints, cp);
1798 ival = *(int *)cp;
1799 cp += sizeof(int);
1800 clen = *cp++;
1801 if (verinfo == NULL ||
1802 ival == verinfo->md_ver_preferred) {
1803 found = 1;
1804 break;
1805 }
1806 if (ival >= verinfo->md_ver_minimum &&
1807 ival <= verinfo->md_ver_maximum &&
1808 ival > bestver) {
1809 bestver = ival;
1810 best = cp;
1811 blen = clen;
1812 }
1813 break;
1814 default:
1815 break;
1816 }
1817 recptr += reclen + sizeof(int);
1818 }
1819 /*
1820 * Finally check if KLD is in the place
1821 */
1822 if (found)
1823 result = linker_lookup_file(path, pathlen, cp, clen, &mattr);
1824 else if (best)
1825 result = linker_lookup_file(path, pathlen, best, blen, &mattr);
1826
1827 /*
1828 * KLD is newer than hints file. What we should do now?
1829 */
1830 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >))
1831 printf("warning: KLD '%s' is newer than the linker.hints"
1832 " file\n", result);
1833bad:
1834 free(pathbuf, M_LINKER);
1835 if (hints)
1836 free(hints, M_TEMP);
1837 if (nd.ni_vp != NULL) {
1838 VOP_UNLOCK(nd.ni_vp, 0);
1839 vn_close(nd.ni_vp, FREAD, cred, td);
1840 VFS_UNLOCK_GIANT(vfslocked);
1841 }
1842 /*
1843 * If nothing found or hints is absent - fallback to the old
1844 * way by using "kldname[.ko]" as module name.
1845 */
1846 if (!found && !bestver && result == NULL)
1847 result = linker_lookup_file(path, pathlen, modname,
1848 modnamelen, NULL);
1849 return (result);
1850}
1851
1852/*
1853 * Lookup KLD which contains requested module in the all directories.
1854 */
1855static char *
1856linker_search_module(const char *modname, int modnamelen,
1857 struct mod_depend *verinfo)
1858{
1859 char *cp, *ep, *result;
1860
1861 /*
1862 * traverse the linker path
1863 */
1864 for (cp = linker_path; *cp; cp = ep + 1) {
1865 /* find the end of this component */
1866 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++);
1867 result = linker_hints_lookup(cp, ep - cp, modname,
1868 modnamelen, verinfo);
1869 if (result != NULL)
1870 return (result);
1871 if (*ep == 0)
1872 break;
1873 }
1874 return (NULL);
1875}
1876
1877/*
1878 * Search for module in all directories listed in the linker_path.
1879 */
1880static char *
1881linker_search_kld(const char *name)
1882{
1883 char *cp, *ep, *result;
1884 int len;
1885
1886 /* qualified at all? */
1887 if (index(name, '/'))
1888 return (linker_strdup(name));
1889
1890 /* traverse the linker path */
1891 len = strlen(name);
1892 for (ep = linker_path; *ep; ep++) {
1893 cp = ep;
1894 /* find the end of this component */
1895 for (; *ep != 0 && *ep != ';'; ep++);
1896 result = linker_lookup_file(cp, ep - cp, name, len, NULL);
1897 if (result != NULL)
1898 return (result);
1899 }
1900 return (NULL);
1901}
1902
1903static const char *
1904linker_basename(const char *path)
1905{
1906 const char *filename;
1907
1908 filename = rindex(path, '/');
1909 if (filename == NULL)
1910 return path;
1911 if (filename[1])
1912 filename++;
1913 return (filename);
1914}
1915
1916#ifdef HWPMC_HOOKS
1917/*
1918 * Inform hwpmc about the set of kernel modules currently loaded.
1919 */
1920void *
1921linker_hwpmc_list_objects(void)
1922{
1923 linker_file_t lf;
1924 struct pmckern_map_in *kobase;
1925 int i, nmappings;
1926
1927 nmappings = 0;
1928 KLD_LOCK();
1929 TAILQ_FOREACH(lf, &linker_files, link)
1930 nmappings++;
1931
1932 /* Allocate nmappings + 1 entries. */
1933 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in),
1934 M_LINKER, M_WAITOK | M_ZERO);
1935 i = 0;
1936 TAILQ_FOREACH(lf, &linker_files, link) {
1937
1938 /* Save the info for this linker file. */
1939 kobase[i].pm_file = lf->filename;
1940 kobase[i].pm_address = (uintptr_t)lf->address;
1941 i++;
1942 }
1943 KLD_UNLOCK();
1944
1945 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?"));
1946
1947 /* The last entry of the malloced area comprises of all zeros. */
1948 KASSERT(kobase[i].pm_file == NULL,
1949 ("linker_hwpmc_list_objects: last object not NULL"));
1950
1951 return ((void *)kobase);
1952}
1953#endif
1954
1955/*
1956 * Find a file which contains given module and load it, if "parent" is not
1957 * NULL, register a reference to it.
1958 */
1959static int
1960linker_load_module(const char *kldname, const char *modname,
1961 struct linker_file *parent, struct mod_depend *verinfo,
1962 struct linker_file **lfpp)
1963{
1964 linker_file_t lfdep;
1965 const char *filename;
1966 char *pathname;
1967 int error;
1968
1969 KLD_LOCK_ASSERT();
1970 if (modname == NULL) {
1971 /*
1972 * We have to load KLD
1973 */
1974 KASSERT(verinfo == NULL, ("linker_load_module: verinfo"
1975 " is not NULL"));
1976 pathname = linker_search_kld(kldname);
1977 } else {
1978 if (modlist_lookup2(modname, verinfo) != NULL)
1979 return (EEXIST);
1980 if (kldname != NULL)
1981 pathname = linker_strdup(kldname);
1982 else if (rootvnode == NULL)
1983 pathname = NULL;
1984 else
1985 /*
1986 * Need to find a KLD with required module
1987 */
1988 pathname = linker_search_module(modname,
1989 strlen(modname), verinfo);
1990 }
1991 if (pathname == NULL)
1992 return (ENOENT);
1993
1994 /*
1995 * Can't load more than one file with the same basename XXX:
1996 * Actually it should be possible to have multiple KLDs with
1997 * the same basename but different path because they can
1998 * provide different versions of the same modules.
1999 */
2000 filename = linker_basename(pathname);
2001 if (linker_find_file_by_name(filename))
2002 error = EEXIST;
2003 else do {
2004 error = linker_load_file(pathname, &lfdep);
2005 if (error)
2006 break;
2007 if (modname && verinfo &&
2008 modlist_lookup2(modname, verinfo) == NULL) {
2009 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE);
2010 error = ENOENT;
2011 break;
2012 }
2013 if (parent) {
2014 error = linker_file_add_dependency(parent, lfdep);
2015 if (error)
2016 break;
2017 }
2018 if (lfpp)
2019 *lfpp = lfdep;
2020 } while (0);
2021 free(pathname, M_LINKER);
2022 return (error);
2023}
2024
2025/*
2026 * This routine is responsible for finding dependencies of userland initiated
2027 * kldload(2)'s of files.
2028 */
2029int
2030linker_load_dependencies(linker_file_t lf)
2031{
2032 linker_file_t lfdep;
2033 struct mod_metadata **start, **stop, **mdp, **nmdp;
2034 struct mod_metadata *mp, *nmp;
2035 struct mod_depend *verinfo;
2036 modlist_t mod;
2037 const char *modname, *nmodname;
2038 int ver, error = 0, count;
2039
2040 /*
2041 * All files are dependant on /kernel.
2042 */
2043 KLD_LOCK_ASSERT();
2044 if (linker_kernel_file) {
2045 linker_kernel_file->refs++;
2046 error = linker_file_add_dependency(lf, linker_kernel_file);
2047 if (error)
2048 return (error);
2049 }
2050 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop,
2051 &count) != 0)
2052 return (0);
2053 for (mdp = start; mdp < stop; mdp++) {
2054 mp = *mdp;
2055 if (mp->md_type != MDT_VERSION)
2056 continue;
2057 modname = mp->md_cval;
2058 ver = ((struct mod_version *)mp->md_data)->mv_version;
2059 mod = modlist_lookup(modname, ver);
2060 if (mod != NULL) {
2061 printf("interface %s.%d already present in the KLD"
2062 " '%s'!\n", modname, ver,
2063 mod->container->filename);
2064 return (EEXIST);
2065 }
2066 }
2067
2068 for (mdp = start; mdp < stop; mdp++) {
2069 mp = *mdp;
2070 if (mp->md_type != MDT_DEPEND)
2071 continue;
2072 modname = mp->md_cval;
2073 verinfo = mp->md_data;
2074 nmodname = NULL;
2075 for (nmdp = start; nmdp < stop; nmdp++) {
2076 nmp = *nmdp;
2077 if (nmp->md_type != MDT_VERSION)
2078 continue;
2079 nmodname = nmp->md_cval;
2080 if (strcmp(modname, nmodname) == 0)
2081 break;
2082 }
2083 if (nmdp < stop)/* early exit, it's a self reference */
2084 continue;
2085 mod = modlist_lookup2(modname, verinfo);
2086 if (mod) { /* woohoo, it's loaded already */
2087 lfdep = mod->container;
2088 lfdep->refs++;
2089 error = linker_file_add_dependency(lf, lfdep);
2090 if (error)
2091 break;
2092 continue;
2093 }
2094 error = linker_load_module(NULL, modname, lf, verinfo, NULL);
2095 if (error) {
2096 printf("KLD %s: depends on %s - not available or"
2097 " version mismatch\n", lf->filename, modname);
2098 break;
2099 }
2100 }
2101
2102 if (error)
2103 return (error);
2104 linker_addmodules(lf, start, stop, 0);
2105 return (error);
2106}
2107
2108static int
2109sysctl_kern_function_list_iterate(const char *name, void *opaque)
2110{
2111 struct sysctl_req *req;
2112
2113 req = opaque;
2114 return (SYSCTL_OUT(req, name, strlen(name) + 1));
2115}
2116
2117/*
2118 * Export a nul-separated, double-nul-terminated list of all function names
2119 * in the kernel.
2120 */
2121static int
2122sysctl_kern_function_list(SYSCTL_HANDLER_ARGS)
2123{
2124 linker_file_t lf;
2125 int error;
2126
2127#ifdef MAC
2128 error = mac_kld_check_stat(req->td->td_ucred);
2129 if (error)
2130 return (error);
2131#endif
2132 error = sysctl_wire_old_buffer(req, 0);
2133 if (error != 0)
2134 return (error);
2135 KLD_LOCK();
2136 TAILQ_FOREACH(lf, &linker_files, link) {
2137 error = LINKER_EACH_FUNCTION_NAME(lf,
2138 sysctl_kern_function_list_iterate, req);
2139 if (error) {
2140 KLD_UNLOCK();
2141 return (error);
2142 }
2143 }
2144 KLD_UNLOCK();
2145 return (SYSCTL_OUT(req, "", 1));
2146}
2147
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