2 * Copyright (c) 2006 Robert N. M. Watson
3 * Copyright (c) 2008-2009 Apple, Inc.
6 * This software was developed by Robert Watson for the TrustedBSD Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include <sys/param.h>
34 #include <sys/condvar.h>
36 #include <sys/eventhandler.h>
37 #include <sys/filio.h>
38 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/mutex.h>
44 #include <sys/queue.h>
45 #include <sys/rwlock.h>
46 #include <sys/selinfo.h>
47 #include <sys/sigio.h>
48 #include <sys/signal.h>
49 #include <sys/signalvar.h>
51 #include <sys/systm.h>
54 #include <security/audit/audit.h>
55 #include <security/audit/audit_ioctl.h>
56 #include <security/audit/audit_private.h>
59 * Implementation of a clonable special device providing a live stream of BSM
60 * audit data. Consumers receive a "tee" of the system audit trail by
61 * default, but may also define alternative event selections using ioctls.
62 * This interface provides unreliable but timely access to audit events.
63 * Consumers should be very careful to avoid introducing event cycles.
69 static MALLOC_DEFINE(M_AUDIT_PIPE, "audit_pipe", "Audit pipes");
70 static MALLOC_DEFINE(M_AUDIT_PIPE_ENTRY, "audit_pipeent",
71 "Audit pipe entries and buffers");
72 static MALLOC_DEFINE(M_AUDIT_PIPE_PRESELECT, "audit_pipe_presel",
73 "Audit pipe preselection structure");
76 * Audit pipe buffer parameters.
78 #define AUDIT_PIPE_QLIMIT_DEFAULT (128)
79 #define AUDIT_PIPE_QLIMIT_MIN (1)
80 #define AUDIT_PIPE_QLIMIT_MAX (1024)
83 * Description of an entry in an audit_pipe.
85 struct audit_pipe_entry {
88 TAILQ_ENTRY(audit_pipe_entry) ape_queue;
92 * Audit pipes allow processes to express "interest" in the set of records
93 * that are delivered via the pipe. They do this in a similar manner to the
94 * mechanism for audit trail configuration, by expressing two global masks,
95 * and optionally expressing per-auid masks. The following data structure is
96 * the per-auid mask description. The global state is stored in the audit
97 * pipe data structure.
99 * We may want to consider a more space/time-efficient data structure once
100 * usage patterns for per-auid specifications are clear.
102 struct audit_pipe_preselect {
105 TAILQ_ENTRY(audit_pipe_preselect) app_list;
109 * Description of an individual audit_pipe. Consists largely of a bounded
112 #define AUDIT_PIPE_ASYNC 0x00000001
113 #define AUDIT_PIPE_NBIO 0x00000002
115 int ap_open; /* Device open? */
118 struct selinfo ap_selinfo;
119 struct sigio *ap_sigio;
122 * Per-pipe mutex protecting most fields in this data structure.
127 * Per-pipe sleep lock serializing user-generated reads and flushes.
128 * uiomove() is called to copy out the current head record's data
129 * while the record remains in the queue, so we prevent other threads
130 * from removing it using this lock.
135 * Condition variable to signal when data has been delivered to a
141 * Various queue-reated variables: qlen and qlimit are a count of
142 * records in the queue; qbyteslen is the number of bytes of data
143 * across all records, and qoffset is the amount read so far of the
144 * first record in the queue. The number of bytes available for
145 * reading in the queue is qbyteslen - qoffset.
153 * Per-pipe operation statistics.
155 u_int64_t ap_inserts; /* Records added. */
156 u_int64_t ap_reads; /* Records read. */
157 u_int64_t ap_drops; /* Records dropped. */
160 * Fields relating to pipe interest: global masks for unmatched
161 * processes (attributable, non-attributable), and a list of specific
162 * interest specifications by auid.
164 int ap_preselect_mode;
165 au_mask_t ap_preselect_flags;
166 au_mask_t ap_preselect_naflags;
167 TAILQ_HEAD(, audit_pipe_preselect) ap_preselect_list;
170 * Current pending record list. Protected by a combination of ap_mtx
171 * and ap_sx. Note particularly that *both* locks are required to
172 * remove a record from the head of the queue, as an in-progress read
173 * may sleep while copying and therefore cannot hold ap_mtx.
175 TAILQ_HEAD(, audit_pipe_entry) ap_queue;
180 TAILQ_ENTRY(audit_pipe) ap_list;
183 #define AUDIT_PIPE_LOCK(ap) mtx_lock(&(ap)->ap_mtx)
184 #define AUDIT_PIPE_LOCK_ASSERT(ap) mtx_assert(&(ap)->ap_mtx, MA_OWNED)
185 #define AUDIT_PIPE_LOCK_DESTROY(ap) mtx_destroy(&(ap)->ap_mtx)
186 #define AUDIT_PIPE_LOCK_INIT(ap) mtx_init(&(ap)->ap_mtx, \
187 "audit_pipe_mtx", NULL, MTX_DEF)
188 #define AUDIT_PIPE_UNLOCK(ap) mtx_unlock(&(ap)->ap_mtx)
189 #define AUDIT_PIPE_MTX(ap) (&(ap)->ap_mtx)
191 #define AUDIT_PIPE_SX_LOCK_DESTROY(ap) sx_destroy(&(ap)->ap_sx)
192 #define AUDIT_PIPE_SX_LOCK_INIT(ap) sx_init(&(ap)->ap_sx, "audit_pipe_sx")
193 #define AUDIT_PIPE_SX_XLOCK_ASSERT(ap) sx_assert(&(ap)->ap_sx, SA_XLOCKED)
194 #define AUDIT_PIPE_SX_XLOCK_SIG(ap) sx_xlock_sig(&(ap)->ap_sx)
195 #define AUDIT_PIPE_SX_XUNLOCK(ap) sx_xunlock(&(ap)->ap_sx)
198 * Global list of audit pipes, rwlock to protect it. Individual record
199 * queues on pipes are protected by per-pipe locks; these locks synchronize
200 * between threads walking the list to deliver to individual pipes and add/
201 * remove of pipes, and are mostly acquired for read.
203 static TAILQ_HEAD(, audit_pipe) audit_pipe_list;
204 static struct rwlock audit_pipe_lock;
206 #define AUDIT_PIPE_LIST_LOCK_INIT() rw_init(&audit_pipe_lock, \
207 "audit_pipe_list_lock")
208 #define AUDIT_PIPE_LIST_RLOCK() rw_rlock(&audit_pipe_lock)
209 #define AUDIT_PIPE_LIST_RUNLOCK() rw_runlock(&audit_pipe_lock)
210 #define AUDIT_PIPE_LIST_WLOCK() rw_wlock(&audit_pipe_lock)
211 #define AUDIT_PIPE_LIST_WLOCK_ASSERT() rw_assert(&audit_pipe_lock, \
213 #define AUDIT_PIPE_LIST_WUNLOCK() rw_wunlock(&audit_pipe_lock)
216 * Cloning related variables and constants.
218 #define AUDIT_PIPE_NAME "auditpipe"
219 static eventhandler_tag audit_pipe_eh_tag;
220 static struct clonedevs *audit_pipe_clones;
223 * Special device methods and definition.
225 static d_open_t audit_pipe_open;
226 static d_close_t audit_pipe_close;
227 static d_read_t audit_pipe_read;
228 static d_ioctl_t audit_pipe_ioctl;
229 static d_poll_t audit_pipe_poll;
230 static d_kqfilter_t audit_pipe_kqfilter;
232 static struct cdevsw audit_pipe_cdevsw = {
233 .d_version = D_VERSION,
234 .d_flags = D_PSEUDO | D_NEEDMINOR,
235 .d_open = audit_pipe_open,
236 .d_close = audit_pipe_close,
237 .d_read = audit_pipe_read,
238 .d_ioctl = audit_pipe_ioctl,
239 .d_poll = audit_pipe_poll,
240 .d_kqfilter = audit_pipe_kqfilter,
241 .d_name = AUDIT_PIPE_NAME,
244 static int audit_pipe_kqread(struct knote *note, long hint);
245 static void audit_pipe_kqdetach(struct knote *note);
247 static struct filterops audit_pipe_read_filterops = {
250 .f_detach = audit_pipe_kqdetach,
251 .f_event = audit_pipe_kqread,
255 * Some global statistics on audit pipes.
257 static int audit_pipe_count; /* Current number of pipes. */
258 static u_int64_t audit_pipe_ever; /* Pipes ever allocated. */
259 static u_int64_t audit_pipe_records; /* Records seen. */
260 static u_int64_t audit_pipe_drops; /* Global record drop count. */
263 * Free an audit pipe entry.
266 audit_pipe_entry_free(struct audit_pipe_entry *ape)
269 free(ape->ape_record, M_AUDIT_PIPE_ENTRY);
270 free(ape, M_AUDIT_PIPE_ENTRY);
274 * Find an audit pipe preselection specification for an auid, if any.
276 static struct audit_pipe_preselect *
277 audit_pipe_preselect_find(struct audit_pipe *ap, au_id_t auid)
279 struct audit_pipe_preselect *app;
281 AUDIT_PIPE_LOCK_ASSERT(ap);
283 TAILQ_FOREACH(app, &ap->ap_preselect_list, app_list) {
284 if (app->app_auid == auid)
291 * Query the per-pipe mask for a specific auid.
294 audit_pipe_preselect_get(struct audit_pipe *ap, au_id_t auid,
297 struct audit_pipe_preselect *app;
301 app = audit_pipe_preselect_find(ap, auid);
303 *maskp = app->app_mask;
307 AUDIT_PIPE_UNLOCK(ap);
312 * Set the per-pipe mask for a specific auid. Add a new entry if needed;
313 * otherwise, update the current entry.
316 audit_pipe_preselect_set(struct audit_pipe *ap, au_id_t auid, au_mask_t mask)
318 struct audit_pipe_preselect *app, *app_new;
321 * Pessimistically assume that the auid doesn't already have a mask
322 * set, and allocate. We will free it if it is unneeded.
324 app_new = malloc(sizeof(*app_new), M_AUDIT_PIPE_PRESELECT, M_WAITOK);
326 app = audit_pipe_preselect_find(ap, auid);
330 app->app_auid = auid;
331 TAILQ_INSERT_TAIL(&ap->ap_preselect_list, app, app_list);
333 app->app_mask = mask;
334 AUDIT_PIPE_UNLOCK(ap);
336 free(app_new, M_AUDIT_PIPE_PRESELECT);
340 * Delete a per-auid mask on an audit pipe.
343 audit_pipe_preselect_delete(struct audit_pipe *ap, au_id_t auid)
345 struct audit_pipe_preselect *app;
349 app = audit_pipe_preselect_find(ap, auid);
351 TAILQ_REMOVE(&ap->ap_preselect_list, app, app_list);
355 AUDIT_PIPE_UNLOCK(ap);
357 free(app, M_AUDIT_PIPE_PRESELECT);
362 * Delete all per-auid masks on an audit pipe.
365 audit_pipe_preselect_flush_locked(struct audit_pipe *ap)
367 struct audit_pipe_preselect *app;
369 AUDIT_PIPE_LOCK_ASSERT(ap);
371 while ((app = TAILQ_FIRST(&ap->ap_preselect_list)) != NULL) {
372 TAILQ_REMOVE(&ap->ap_preselect_list, app, app_list);
373 free(app, M_AUDIT_PIPE_PRESELECT);
378 audit_pipe_preselect_flush(struct audit_pipe *ap)
382 audit_pipe_preselect_flush_locked(ap);
383 AUDIT_PIPE_UNLOCK(ap);
387 * Determine whether a specific audit pipe matches a record with these
388 * properties. Algorithm is as follows:
390 * - If the pipe is configured to track the default trail configuration, then
391 * use the results of global preselection matching.
392 * - If not, search for a specifically configured auid entry matching the
393 * event. If an entry is found, use that.
394 * - Otherwise, use the default flags or naflags configured for the pipe.
397 audit_pipe_preselect_check(struct audit_pipe *ap, au_id_t auid,
398 au_event_t event, au_class_t class, int sorf, int trail_preselect)
400 struct audit_pipe_preselect *app;
402 AUDIT_PIPE_LOCK_ASSERT(ap);
404 switch (ap->ap_preselect_mode) {
405 case AUDITPIPE_PRESELECT_MODE_TRAIL:
406 return (trail_preselect);
408 case AUDITPIPE_PRESELECT_MODE_LOCAL:
409 app = audit_pipe_preselect_find(ap, auid);
411 if (auid == AU_DEFAUDITID)
412 return (au_preselect(event, class,
413 &ap->ap_preselect_naflags, sorf));
415 return (au_preselect(event, class,
416 &ap->ap_preselect_flags, sorf));
418 return (au_preselect(event, class, &app->app_mask,
422 panic("audit_pipe_preselect_check: mode %d",
423 ap->ap_preselect_mode);
430 * Determine whether there exists a pipe interested in a record with specific
434 audit_pipe_preselect(au_id_t auid, au_event_t event, au_class_t class,
435 int sorf, int trail_preselect)
437 struct audit_pipe *ap;
439 /* Lockless read to avoid acquiring the global lock if not needed. */
440 if (TAILQ_EMPTY(&audit_pipe_list))
443 AUDIT_PIPE_LIST_RLOCK();
444 TAILQ_FOREACH(ap, &audit_pipe_list, ap_list) {
446 if (audit_pipe_preselect_check(ap, auid, event, class, sorf,
448 AUDIT_PIPE_UNLOCK(ap);
449 AUDIT_PIPE_LIST_RUNLOCK();
452 AUDIT_PIPE_UNLOCK(ap);
454 AUDIT_PIPE_LIST_RUNLOCK();
459 * Append individual record to a queue -- allocate queue-local buffer, and
460 * add to the queue. If the queue is full or we can't allocate memory, drop
464 audit_pipe_append(struct audit_pipe *ap, void *record, u_int record_len)
466 struct audit_pipe_entry *ape;
468 AUDIT_PIPE_LOCK_ASSERT(ap);
470 if (ap->ap_qlen >= ap->ap_qlimit) {
476 ape = malloc(sizeof(*ape), M_AUDIT_PIPE_ENTRY, M_NOWAIT | M_ZERO);
483 ape->ape_record = malloc(record_len, M_AUDIT_PIPE_ENTRY, M_NOWAIT);
484 if (ape->ape_record == NULL) {
485 free(ape, M_AUDIT_PIPE_ENTRY);
491 bcopy(record, ape->ape_record, record_len);
492 ape->ape_record_len = record_len;
494 TAILQ_INSERT_TAIL(&ap->ap_queue, ape, ape_queue);
497 ap->ap_qbyteslen += ape->ape_record_len;
498 selwakeuppri(&ap->ap_selinfo, PSOCK);
499 KNOTE_LOCKED(&ap->ap_selinfo.si_note, 0);
500 if (ap->ap_flags & AUDIT_PIPE_ASYNC)
501 pgsigio(&ap->ap_sigio, SIGIO, 0);
502 cv_broadcast(&ap->ap_cv);
506 * audit_pipe_submit(): audit_worker submits audit records via this
507 * interface, which arranges for them to be delivered to pipe queues.
510 audit_pipe_submit(au_id_t auid, au_event_t event, au_class_t class, int sorf,
511 int trail_select, void *record, u_int record_len)
513 struct audit_pipe *ap;
516 * Lockless read to avoid lock overhead if pipes are not in use.
518 if (TAILQ_FIRST(&audit_pipe_list) == NULL)
521 AUDIT_PIPE_LIST_RLOCK();
522 TAILQ_FOREACH(ap, &audit_pipe_list, ap_list) {
524 if (audit_pipe_preselect_check(ap, auid, event, class, sorf,
526 audit_pipe_append(ap, record, record_len);
527 AUDIT_PIPE_UNLOCK(ap);
529 AUDIT_PIPE_LIST_RUNLOCK();
531 /* Unlocked increment. */
532 audit_pipe_records++;
536 * audit_pipe_submit_user(): the same as audit_pipe_submit(), except that
537 * since we don't currently have selection information available, it is
538 * delivered to the pipe unconditionally.
540 * XXXRW: This is a bug. The BSM check routine for submitting a user record
541 * should parse that information and return it.
544 audit_pipe_submit_user(void *record, u_int record_len)
546 struct audit_pipe *ap;
549 * Lockless read to avoid lock overhead if pipes are not in use.
551 if (TAILQ_FIRST(&audit_pipe_list) == NULL)
554 AUDIT_PIPE_LIST_RLOCK();
555 TAILQ_FOREACH(ap, &audit_pipe_list, ap_list) {
557 audit_pipe_append(ap, record, record_len);
558 AUDIT_PIPE_UNLOCK(ap);
560 AUDIT_PIPE_LIST_RUNLOCK();
562 /* Unlocked increment. */
563 audit_pipe_records++;
567 * Allocate a new audit pipe. Connects the pipe, on success, to the global
568 * list and updates statistics.
570 static struct audit_pipe *
571 audit_pipe_alloc(void)
573 struct audit_pipe *ap;
575 AUDIT_PIPE_LIST_WLOCK_ASSERT();
577 ap = malloc(sizeof(*ap), M_AUDIT_PIPE, M_NOWAIT | M_ZERO);
580 ap->ap_qlimit = AUDIT_PIPE_QLIMIT_DEFAULT;
581 TAILQ_INIT(&ap->ap_queue);
582 knlist_init_mtx(&ap->ap_selinfo.si_note, AUDIT_PIPE_MTX(ap));
583 AUDIT_PIPE_LOCK_INIT(ap);
584 AUDIT_PIPE_SX_LOCK_INIT(ap);
585 cv_init(&ap->ap_cv, "audit_pipe");
588 * Default flags, naflags, and auid-specific preselection settings to
589 * 0. Initialize the mode to the global trail so that if praudit(1)
590 * is run on /dev/auditpipe, it sees events associated with the
591 * default trail. Pipe-aware application can clear the flag, set
592 * custom masks, and flush the pipe as needed.
594 bzero(&ap->ap_preselect_flags, sizeof(ap->ap_preselect_flags));
595 bzero(&ap->ap_preselect_naflags, sizeof(ap->ap_preselect_naflags));
596 TAILQ_INIT(&ap->ap_preselect_list);
597 ap->ap_preselect_mode = AUDITPIPE_PRESELECT_MODE_TRAIL;
600 * Add to global list and update global statistics.
602 TAILQ_INSERT_HEAD(&audit_pipe_list, ap, ap_list);
610 * Flush all records currently present in an audit pipe; assume mutex is held.
613 audit_pipe_flush(struct audit_pipe *ap)
615 struct audit_pipe_entry *ape;
617 AUDIT_PIPE_LOCK_ASSERT(ap);
619 while ((ape = TAILQ_FIRST(&ap->ap_queue)) != NULL) {
620 TAILQ_REMOVE(&ap->ap_queue, ape, ape_queue);
621 ap->ap_qbyteslen -= ape->ape_record_len;
622 audit_pipe_entry_free(ape);
627 KASSERT(ap->ap_qlen == 0, ("audit_pipe_free: ap_qbyteslen"));
628 KASSERT(ap->ap_qbyteslen == 0, ("audit_pipe_flush: ap_qbyteslen"));
632 * Free an audit pipe; this means freeing all preselection state and all
633 * records in the pipe. Assumes global write lock and pipe mutex are held to
634 * prevent any new records from being inserted during the free, and that the
635 * audit pipe is still on the global list.
638 audit_pipe_free(struct audit_pipe *ap)
641 AUDIT_PIPE_LIST_WLOCK_ASSERT();
642 AUDIT_PIPE_LOCK_ASSERT(ap);
644 audit_pipe_preselect_flush_locked(ap);
645 audit_pipe_flush(ap);
646 cv_destroy(&ap->ap_cv);
647 AUDIT_PIPE_SX_LOCK_DESTROY(ap);
648 AUDIT_PIPE_LOCK_DESTROY(ap);
649 knlist_destroy(&ap->ap_selinfo.si_note);
650 TAILQ_REMOVE(&audit_pipe_list, ap, ap_list);
651 free(ap, M_AUDIT_PIPE);
656 * Audit pipe clone routine -- provide specific requested audit pipe, or a
657 * fresh one if a specific one is not requested.
660 audit_pipe_clone(void *arg, struct ucred *cred, char *name, int namelen,
668 if (strcmp(name, AUDIT_PIPE_NAME) == 0)
670 else if (dev_stdclone(name, NULL, AUDIT_PIPE_NAME, &u) != 1)
673 i = clone_create(&audit_pipe_clones, &audit_pipe_cdevsw, &u, dev, 0);
675 *dev = make_dev(&audit_pipe_cdevsw, u, UID_ROOT,
676 GID_WHEEL, 0600, "%s%d", AUDIT_PIPE_NAME, u);
679 (*dev)->si_flags |= SI_CHEAPCLONE;
685 * Audit pipe open method. Explicit privilege check isn't used as this
686 * allows file permissions on the special device to be used to grant audit
687 * review access. Those file permissions should be managed carefully.
690 audit_pipe_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
692 struct audit_pipe *ap;
694 AUDIT_PIPE_LIST_WLOCK();
697 ap = audit_pipe_alloc();
699 AUDIT_PIPE_LIST_WUNLOCK();
704 KASSERT(ap->ap_open, ("audit_pipe_open: ap && !ap_open"));
705 AUDIT_PIPE_LIST_WUNLOCK();
708 ap->ap_open = 1; /* No lock required yet. */
709 AUDIT_PIPE_LIST_WUNLOCK();
710 fsetown(td->td_proc->p_pid, &ap->ap_sigio);
715 * Close audit pipe, tear down all records, etc.
718 audit_pipe_close(struct cdev *dev, int fflag, int devtype, struct thread *td)
720 struct audit_pipe *ap;
723 KASSERT(ap != NULL, ("audit_pipe_close: ap == NULL"));
724 KASSERT(ap->ap_open, ("audit_pipe_close: !ap_open"));
726 funsetown(&ap->ap_sigio);
727 AUDIT_PIPE_LIST_WLOCK();
732 AUDIT_PIPE_LIST_WUNLOCK();
737 * Audit pipe ioctl() routine. Handle file descriptor and audit pipe layer
741 audit_pipe_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag,
744 struct auditpipe_ioctl_preselect *aip;
745 struct audit_pipe *ap;
751 KASSERT(ap != NULL, ("audit_pipe_ioctl: ap == NULL"));
754 * Audit pipe ioctls: first come standard device node ioctls, then
755 * manipulation of pipe settings, and finally, statistics query
762 ap->ap_flags |= AUDIT_PIPE_NBIO;
764 ap->ap_flags &= ~AUDIT_PIPE_NBIO;
765 AUDIT_PIPE_UNLOCK(ap);
771 *(int *)data = ap->ap_qbyteslen - ap->ap_qoffset;
772 AUDIT_PIPE_UNLOCK(ap);
779 ap->ap_flags |= AUDIT_PIPE_ASYNC;
781 ap->ap_flags &= ~AUDIT_PIPE_ASYNC;
782 AUDIT_PIPE_UNLOCK(ap);
787 error = fsetown(*(int *)data, &ap->ap_sigio);
791 *(int *)data = fgetown(&ap->ap_sigio);
795 case AUDITPIPE_GET_QLEN:
796 *(u_int *)data = ap->ap_qlen;
800 case AUDITPIPE_GET_QLIMIT:
801 *(u_int *)data = ap->ap_qlimit;
805 case AUDITPIPE_SET_QLIMIT:
806 /* Lockless integer write. */
807 if (*(u_int *)data >= AUDIT_PIPE_QLIMIT_MIN ||
808 *(u_int *)data <= AUDIT_PIPE_QLIMIT_MAX) {
809 ap->ap_qlimit = *(u_int *)data;
815 case AUDITPIPE_GET_QLIMIT_MIN:
816 *(u_int *)data = AUDIT_PIPE_QLIMIT_MIN;
820 case AUDITPIPE_GET_QLIMIT_MAX:
821 *(u_int *)data = AUDIT_PIPE_QLIMIT_MAX;
825 case AUDITPIPE_GET_PRESELECT_FLAGS:
827 maskp = (au_mask_t *)data;
828 *maskp = ap->ap_preselect_flags;
829 AUDIT_PIPE_UNLOCK(ap);
833 case AUDITPIPE_SET_PRESELECT_FLAGS:
835 maskp = (au_mask_t *)data;
836 ap->ap_preselect_flags = *maskp;
837 AUDIT_PIPE_UNLOCK(ap);
841 case AUDITPIPE_GET_PRESELECT_NAFLAGS:
843 maskp = (au_mask_t *)data;
844 *maskp = ap->ap_preselect_naflags;
845 AUDIT_PIPE_UNLOCK(ap);
849 case AUDITPIPE_SET_PRESELECT_NAFLAGS:
851 maskp = (au_mask_t *)data;
852 ap->ap_preselect_naflags = *maskp;
853 AUDIT_PIPE_UNLOCK(ap);
857 case AUDITPIPE_GET_PRESELECT_AUID:
858 aip = (struct auditpipe_ioctl_preselect *)data;
859 error = audit_pipe_preselect_get(ap, aip->aip_auid,
863 case AUDITPIPE_SET_PRESELECT_AUID:
864 aip = (struct auditpipe_ioctl_preselect *)data;
865 audit_pipe_preselect_set(ap, aip->aip_auid, aip->aip_mask);
869 case AUDITPIPE_DELETE_PRESELECT_AUID:
870 auid = *(au_id_t *)data;
871 error = audit_pipe_preselect_delete(ap, auid);
874 case AUDITPIPE_FLUSH_PRESELECT_AUID:
875 audit_pipe_preselect_flush(ap);
879 case AUDITPIPE_GET_PRESELECT_MODE:
881 *(int *)data = ap->ap_preselect_mode;
882 AUDIT_PIPE_UNLOCK(ap);
886 case AUDITPIPE_SET_PRESELECT_MODE:
889 case AUDITPIPE_PRESELECT_MODE_TRAIL:
890 case AUDITPIPE_PRESELECT_MODE_LOCAL:
892 ap->ap_preselect_mode = mode;
893 AUDIT_PIPE_UNLOCK(ap);
902 case AUDITPIPE_FLUSH:
903 if (AUDIT_PIPE_SX_XLOCK_SIG(ap) != 0)
906 audit_pipe_flush(ap);
907 AUDIT_PIPE_UNLOCK(ap);
908 AUDIT_PIPE_SX_XUNLOCK(ap);
912 case AUDITPIPE_GET_MAXAUDITDATA:
913 *(u_int *)data = MAXAUDITDATA;
917 case AUDITPIPE_GET_INSERTS:
918 *(u_int *)data = ap->ap_inserts;
922 case AUDITPIPE_GET_READS:
923 *(u_int *)data = ap->ap_reads;
927 case AUDITPIPE_GET_DROPS:
928 *(u_int *)data = ap->ap_drops;
932 case AUDITPIPE_GET_TRUNCATES:
944 * Audit pipe read. Read one or more partial or complete records to user
948 audit_pipe_read(struct cdev *dev, struct uio *uio, int flag)
950 struct audit_pipe_entry *ape;
951 struct audit_pipe *ap;
956 KASSERT(ap != NULL, ("audit_pipe_read: ap == NULL"));
959 * We hold an sx(9) lock over read and flush because we rely on the
960 * stability of a record in the queue during uiomove(9).
962 if (AUDIT_PIPE_SX_XLOCK_SIG(ap) != 0)
965 while (TAILQ_EMPTY(&ap->ap_queue)) {
966 if (ap->ap_flags & AUDIT_PIPE_NBIO) {
967 AUDIT_PIPE_UNLOCK(ap);
968 AUDIT_PIPE_SX_XUNLOCK(ap);
971 error = cv_wait_sig(&ap->ap_cv, AUDIT_PIPE_MTX(ap));
973 AUDIT_PIPE_UNLOCK(ap);
974 AUDIT_PIPE_SX_XUNLOCK(ap);
980 * Copy as many remaining bytes from the current record to userspace
981 * as we can. Keep processing records until we run out of records in
982 * the queue, or until the user buffer runs out of space.
984 * Note: we rely on the SX lock to maintain ape's stability here.
987 while ((ape = TAILQ_FIRST(&ap->ap_queue)) != NULL &&
988 uio->uio_resid > 0) {
989 AUDIT_PIPE_LOCK_ASSERT(ap);
991 KASSERT(ape->ape_record_len > ap->ap_qoffset,
992 ("audit_pipe_read: record_len > qoffset (1)"));
993 toread = MIN(ape->ape_record_len - ap->ap_qoffset,
995 AUDIT_PIPE_UNLOCK(ap);
996 error = uiomove((char *)ape->ape_record + ap->ap_qoffset,
999 AUDIT_PIPE_SX_XUNLOCK(ap);
1004 * If the copy succeeded, update book-keeping, and if no
1005 * bytes remain in the current record, free it.
1007 AUDIT_PIPE_LOCK(ap);
1008 KASSERT(TAILQ_FIRST(&ap->ap_queue) == ape,
1009 ("audit_pipe_read: queue out of sync after uiomove"));
1010 ap->ap_qoffset += toread;
1011 KASSERT(ape->ape_record_len >= ap->ap_qoffset,
1012 ("audit_pipe_read: record_len >= qoffset (2)"));
1013 if (ap->ap_qoffset == ape->ape_record_len) {
1014 TAILQ_REMOVE(&ap->ap_queue, ape, ape_queue);
1015 ap->ap_qbyteslen -= ape->ape_record_len;
1016 audit_pipe_entry_free(ape);
1021 AUDIT_PIPE_UNLOCK(ap);
1022 AUDIT_PIPE_SX_XUNLOCK(ap);
1030 audit_pipe_poll(struct cdev *dev, int events, struct thread *td)
1032 struct audit_pipe *ap;
1037 KASSERT(ap != NULL, ("audit_pipe_poll: ap == NULL"));
1039 if (events & (POLLIN | POLLRDNORM)) {
1040 AUDIT_PIPE_LOCK(ap);
1041 if (TAILQ_FIRST(&ap->ap_queue) != NULL)
1042 revents |= events & (POLLIN | POLLRDNORM);
1044 selrecord(td, &ap->ap_selinfo);
1045 AUDIT_PIPE_UNLOCK(ap);
1051 * Audit pipe kqfilter.
1054 audit_pipe_kqfilter(struct cdev *dev, struct knote *kn)
1056 struct audit_pipe *ap;
1059 KASSERT(ap != NULL, ("audit_pipe_kqfilter: ap == NULL"));
1061 if (kn->kn_filter != EVFILT_READ)
1064 kn->kn_fop = &audit_pipe_read_filterops;
1067 AUDIT_PIPE_LOCK(ap);
1068 knlist_add(&ap->ap_selinfo.si_note, kn, 1);
1069 AUDIT_PIPE_UNLOCK(ap);
1074 * Return true if there are records available for reading on the pipe.
1077 audit_pipe_kqread(struct knote *kn, long hint)
1079 struct audit_pipe *ap;
1081 ap = (struct audit_pipe *)kn->kn_hook;
1082 KASSERT(ap != NULL, ("audit_pipe_kqread: ap == NULL"));
1083 AUDIT_PIPE_LOCK_ASSERT(ap);
1085 if (ap->ap_qlen != 0) {
1086 kn->kn_data = ap->ap_qbyteslen - ap->ap_qoffset;
1095 * Detach kqueue state from audit pipe.
1098 audit_pipe_kqdetach(struct knote *kn)
1100 struct audit_pipe *ap;
1102 ap = (struct audit_pipe *)kn->kn_hook;
1103 KASSERT(ap != NULL, ("audit_pipe_kqdetach: ap == NULL"));
1105 AUDIT_PIPE_LOCK(ap);
1106 knlist_remove(&ap->ap_selinfo.si_note, kn, 1);
1107 AUDIT_PIPE_UNLOCK(ap);
1111 * Initialize the audit pipe system.
1114 audit_pipe_init(void *unused)
1117 TAILQ_INIT(&audit_pipe_list);
1118 AUDIT_PIPE_LIST_LOCK_INIT();
1120 clone_setup(&audit_pipe_clones);
1121 audit_pipe_eh_tag = EVENTHANDLER_REGISTER(dev_clone,
1122 audit_pipe_clone, 0, 1000);
1123 if (audit_pipe_eh_tag == NULL)
1124 panic("audit_pipe_init: EVENTHANDLER_REGISTER");
1127 SYSINIT(audit_pipe_init, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, audit_pipe_init,