PERFORCE change 84353 for review
Robert Watson
rwatson at FreeBSD.org
Tue Sep 27 16:18:50 GMT 2005
http://perforce.freebsd.org/chv.cgi?CH=84353
Change 84353 by rwatson at rwatson_zoo on 2005/09/27 16:18:33
Move implementation of /dev/audit into audit_trigger.c, exposing
an additional function, audit_trigger_init(), which will be run
from audit_init(). Given the audit trigger queue its own mutex.
Trim unneeded includes.
While here, since our trigger mechanism doesn't support failure
to enqueue a message (unlike mach port writes), remove failure
handling from kern_audit.c, which simplifies things quite a bit.
Annotate that the implementation broken out here is actually
wsalamon's, so should probably be under his copyright and license,
not an Apple one.
Affected files ...
.. //depot/projects/trustedbsd/audit3/sys/conf/files#7 edit
.. //depot/projects/trustedbsd/audit3/sys/security/audit/audit_private.h#2 edit
.. //depot/projects/trustedbsd/audit3/sys/security/audit/audit_trigger.c#2 edit
.. //depot/projects/trustedbsd/audit3/sys/security/audit/kern_audit.c#42 edit
Differences ...
==== //depot/projects/trustedbsd/audit3/sys/conf/files#7 (text+ko) ====
@@ -1843,6 +1843,7 @@
posix4/p1003_1b.c standard
posix4/posix4_mib.c standard
rpc/rpcclnt.c optional nfsclient
+security/audit/audit_trigger.c optional audit
security/audit/kern_audit.c standard
security/audit/kern_bsm_audit.c optional audit
security/audit/kern_bsm_klib.c optional audit
==== //depot/projects/trustedbsd/audit3/sys/security/audit/audit_private.h#2 (text+ko) ====
@@ -51,6 +51,13 @@
int semctl_to_event(int cmr);
void canon_path(struct thread *td, char *path, char *cpath);
+/*
+ * Audit trigger events notify user space of kernel audit conditions
+ * asynchronously.
+ */
+void audit_trigger_init(void);
+void send_trigger(unsigned int trigger);
+
#endif /* _KERNEL */
#endif /* ! _BSM_AUDIT_KLIB_H_ */
==== //depot/projects/trustedbsd/audit3/sys/security/audit/audit_trigger.c#2 (text+ko) ====
@@ -18,183 +18,22 @@
* under the License.
*
* @APPLE_LICENSE_HEADER_END@
+ *
+ * XXXRW: Should be a wsalamon copyright and license?
*/
#include <sys/param.h>
-#include <sys/condvar.h>
#include <sys/conf.h>
-#include <sys/file.h>
-#include <sys/filedesc.h>
-#include <sys/fcntl.h>
-#include <sys/ipc.h>
#include <sys/kernel.h>
-#include <sys/kthread.h>
#include <sys/malloc.h>
-#include <sys/mount.h>
-#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/queue.h>
-#include <sys/socket.h>
-#include <sys/socketvar.h>
-#include <sys/protosw.h>
-#include <sys/domain.h>
-#include <sys/sysproto.h>
-#include <sys/sysent.h>
#include <sys/systm.h>
-#include <sys/ucred.h>
#include <sys/uio.h>
-#include <sys/un.h>
-#include <sys/unistd.h>
-#include <sys/vnode.h>
-#include <netinet/in.h>
-#include <netinet/in_pcb.h>
-
-#include <bsm/audit.h>
-#include <bsm/audit_kevents.h>
-#include <security/audit/audit.h>
-#include <security/audit/audit_klib.h>
-
-/*
- * XXXAUDIT: Might be nice to use a UMA zone for records, and malloc(9) only
- * for things like triggers, temporary storage, etc.
- */
-MALLOC_DEFINE(M_AUDIT, "audit", "Audit event records");
-
-#ifdef AUDIT
-
-/*
- * The AUDIT_EXCESSIVELY_VERBOSE define enables a number of
- * gratuitously noisy printf's to the console. Due to the
- * volume, it should be left off unless you want your system
- * to churn a lot whenever the audit record flow gets high.
- */
-//#define AUDIT_EXCESSIVELY_VERBOSE
-#ifdef AUDIT_EXCESSIVELY_VERBOSE
-#define AUDIT_PRINTF(x) printf x
-#else
-#define AUDIT_PRINTF(X)
-#endif
-
-#if 0
-#if DIAGNOSTIC
-#if defined(assert)
-#undef assert()
-#endif
-#define assert(cond) \
- ((void) ((cond) ? 0 : panic("%s:%d (%s)", __FILE__, __LINE__, # cond)))
-#else
-#include <kern/assert.h>
-#endif /* DIAGNOSTIC */
-#endif
-#define assert(x) KASSERT(x, x)
-
-/*
- * Define the audit control flags.
- */
-int audit_enabled;
-int audit_suspended;
-
-/*
- * Mutex to protect global variables shared between various threads and
- * processes.
- */
-static struct mtx audit_mtx;
-
-/*
- * Queue of audit records ready for delivery to disk. We insert new
- * records at the tail, and remove records from the head. Also,
- * a count of the number of records used for checking queue depth.
- * In addition, a counter of records that we have allocated but are
- * not yet in the queue, which is needed to estimate the total
- * size of the combined set of records outstanding in the system.
- */
-static TAILQ_HEAD(, kaudit_record) audit_q;
-static int audit_q_len;
-static int audit_pre_q_len;
-
-/*
- * Condition variable to signal to the worker that it has work to do:
- * either new records are in the queue, or a log replacement is taking
- * place.
- */
-static struct cv audit_cv;
-
-/*
- * Worker thread that will schedule disk I/O, etc.
- */
-static struct proc *audit_thread;
-
-/*
- * When an audit log is rotated, the actual rotation must be performed
- * by the audit worker thread, as it may have outstanding writes on the
- * current audit log. audit_replacement_vp holds the vnode replacing
- * the current vnode. We can't let more than one replacement occur
- * at a time, so if more than one thread requests a replacement, only
- * one can have the replacement "in progress" at any given moment. If
- * a thread tries to replace the audit vnode and discovers a replacement
- * is already in progress (i.e., audit_replacement_flag != 0), then it
- * will sleep on audit_replacement_cv waiting its turn to perform a
- * replacement. When a replacement is completed, this cv is signalled
- * by the worker thread so a waiting thread can start another replacement.
- * We also store a credential to perform audit log write operations with.
- *
- * The current credential and vnode are thread-local to audit_worker.
- */
-static struct cv audit_replacement_cv;
-
-static int audit_replacement_flag;
-static struct vnode *audit_replacement_vp;
-static struct ucred *audit_replacement_cred;
-
-/*
- * Condition variable to signal to the worker that it has work to do:
- * either new records are in the queue, or a log replacement is taking
- * place.
- */
-static struct cv audit_commit_cv;
-
-/*
- * Condition variable for auditing threads wait on when in fail-stop mode.
- * Threads wait on this CV forever (and ever), never seeing the light of
- * day again.
- */
-static struct cv audit_fail_cv;
-
-static struct au_qctrl audit_qctrl;
-
-/*
- * Flags to use on audit files when opening and closing.
- */
-const static int audit_open_flags = FWRITE | O_APPEND;
-const static int audit_close_flags = FWRITE | O_APPEND;
-
-/*
- * Global audit statistiscs.
- */
-static struct audit_fstat audit_fstat;
-
-/*
- Preselection mask for non-attributable events.
- */
-static struct au_mask audit_nae_mask;
+#include <security/audit/audit_private.h>
/*
- * Flags related to Kernel->user-space communication.
- */
-static int audit_file_rotate_wait;
-
-/*
- * Flags controlling behavior in low storage situations.
- * Should we panic if a write fails? Should we fail stop
- * if we're out of disk space? Are we currently "failing
- * stop" due to out of disk space?
- */
-static int audit_panic_on_write_fail;
-static int audit_fail_stop;
-static int audit_in_failure;
-
-/*
* Structures and operations to support the basic character special device
* used to communicate with userland.
*/
@@ -205,11 +44,7 @@
static struct cdev *audit_dev;
static int audit_isopen = 0;
static TAILQ_HEAD(, trigger_info) trigger_list;
-
-/*
- * Forward declarations of static functions.
- */
-static void audit_shutdown(void *arg, int howto);
+static struct mtx audit_trigger_mtx;
static int
audit_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
@@ -217,7 +52,7 @@
int error;
// Only one process may open the device at a time
- mtx_lock(&audit_mtx);
+ mtx_lock(&audit_trigger_mtx);
if (!audit_isopen) {
error = 0;
audit_isopen = 1;
@@ -227,7 +62,7 @@
*/
error = EOPNOTSUPP;
}
- mtx_unlock(&audit_mtx);
+ mtx_unlock(&audit_trigger_mtx);
return (error);
}
@@ -238,14 +73,14 @@
struct trigger_info *ti;
/* Drain the queue of pending trigger events */
- mtx_lock(&audit_mtx);
+ mtx_lock(&audit_trigger_mtx);
audit_isopen = 0;
while (!TAILQ_EMPTY(&trigger_list)) {
ti = TAILQ_FIRST(&trigger_list);
TAILQ_REMOVE(&trigger_list, ti, list);
free(ti, M_AUDIT);
}
- mtx_unlock(&audit_mtx);
+ mtx_unlock(&audit_trigger_mtx);
return (0);
}
@@ -255,9 +90,9 @@
int error = 0;
struct trigger_info *ti = NULL;
- mtx_lock(&audit_mtx);
+ mtx_lock(&audit_trigger_mtx);
while (TAILQ_EMPTY(&trigger_list)) {
- error = msleep(&trigger_list, &audit_mtx, PSOCK | PCATCH,
+ error = msleep(&trigger_list, &audit_trigger_mtx, PSOCK | PCATCH,
"auditd", 0);
if (error)
break;
@@ -266,7 +101,7 @@
ti = TAILQ_FIRST(&trigger_list);
TAILQ_REMOVE(&trigger_list, ti, list);
}
- mtx_unlock(&audit_mtx);
+ mtx_unlock(&audit_trigger_mtx);
if (!error) {
error = uiomove(ti, sizeof *ti, uio);
free(ti, M_AUDIT);
@@ -282,29 +117,25 @@
return EOPNOTSUPP;
}
-/*
- * XXXAUDIT: Since we can't fail this call, we should not have a return
- * value.
- */
-static int
+void
send_trigger(unsigned int trigger)
{
struct trigger_info *ti;
/* If nobody's listening, we ain't talking */
if (!audit_isopen)
- return 0;
+ return;
/*
* XXXAUDIT: Use a condition variable instead of msleep/wakeup?
*/
ti = malloc(sizeof *ti, M_AUDIT, M_WAITOK);
- mtx_lock(&audit_mtx);
+ mtx_lock(&audit_trigger_mtx);
ti->trigger = trigger;
TAILQ_INSERT_TAIL(&trigger_list, ti, list);
wakeup(&trigger_list);
- mtx_unlock(&audit_mtx);
- return 0;
+ mtx_unlock(&audit_trigger_mtx);
+ return;
}
static struct cdevsw audit_cdevsw = {
@@ -316,463 +147,16 @@
.d_name = "audit"
};
-/*
- * XXXAUDIT: For consistency, perhaps audit_record_free()?
- */
-static void
-audit_free(struct kaudit_record *ar)
-{
-
- if (ar->k_ar.ar_arg_upath1 != NULL) {
- free(ar->k_ar.ar_arg_upath1, M_AUDIT);
- }
- if (ar->k_ar.ar_arg_upath2 != NULL) {
- free(ar->k_ar.ar_arg_upath2, M_AUDIT);
- }
- if (ar->k_ar.ar_arg_kpath1 != NULL) {
- free(ar->k_ar.ar_arg_kpath1, M_AUDIT);
- }
- if (ar->k_ar.ar_arg_kpath2 != NULL) {
- free(ar->k_ar.ar_arg_kpath2, M_AUDIT);
- }
- if (ar->k_ar.ar_arg_text != NULL) {
- free(ar->k_ar.ar_arg_text, M_AUDIT);
- }
- if (ar->k_udata != NULL) {
- free(ar->k_udata, M_AUDIT);
- }
- free(ar, M_AUDIT);
-}
-
-/*
- * XXXAUDIT: Should adjust comments below to make it clear that we get to
- * this point only if we believe we have storage, so not having space here
- * is a violation of invariants derived from administrative procedures.
- * I.e., someone else has written to the audit partition, leaving less space
- * than we accounted for.
- */
-static int
-audit_record_write(struct vnode *vp, struct kaudit_record *ar,
- struct ucred *cred, struct thread *td)
-{
- int ret;
- long temp;
- struct au_record *bsm;
- struct vattr vattr;
- struct statfs *mnt_stat = &vp->v_mount->mnt_stat;
- int vfslocked;
-
- vfslocked = VFS_LOCK_GIANT(vp->v_mount);
-
- /*
- * First, gather statistics on the audit log file and file system
- * so that we know how we're doing on space. In both cases,
- * if we're unable to perform the operation, we drop the record
- * and return. However, this is arguably an assertion failure.
- * XXX Need a FreeBSD equivalent.
- */
- ret = VFS_STATFS(vp->v_mount, mnt_stat, td);
- if (ret)
- goto out;
-
- ret = VOP_GETATTR(vp, &vattr, cred, td);
- if (ret)
- goto out;
-
- /* update the global stats struct */
- audit_fstat.af_currsz = vattr.va_size;
-
- /*
- * XXX Need to decide what to do if the trigger to the audit daemon
- * fails.
- */
-
- /*
- * If we fall below minimum free blocks (hard limit), tell the audit
- * daemon to force a rotation off of the file system. We also stop
- * writing, which means this audit record is probably lost.
- * If we fall below the minimum percent free blocks (soft limit),
- * then kindly suggest to the audit daemon to do something.
- */
- if (mnt_stat->f_bfree < AUDIT_HARD_LIMIT_FREE_BLOCKS) {
- ret = send_trigger(AUDIT_TRIGGER_NO_SPACE);
- if (ret != 0) {
- printf(
- "Failed audit_triggers(AUDIT_TRIGGER_NO_SPACE): %d\n", ret);
- /*
- * XXX: What to do here? Disable auditing?
- * panic?
- */
- }
- /* Hopefully userspace did something about all the previous
- * triggers that were sent prior to this critical condition.
- * If fail-stop is set, then we're done; goodnight Gracie.
- */
- if (audit_fail_stop)
- panic("Audit log space exhausted and fail-stop set.");
- else {
- audit_suspended = 1;
- ret = ENOSPC;
- goto out;
- }
- } else
- /*
- * Send a message to the audit daemon that disk space
- * is getting low.
- *
- * XXXAUDIT: Check math and block size calculation here.
- */
- if (audit_qctrl.aq_minfree != 0) {
- temp = mnt_stat->f_blocks / (100 /
- audit_qctrl.aq_minfree);
- if (mnt_stat->f_bfree < temp) {
- ret = send_trigger(AUDIT_TRIGGER_LOW_SPACE);
- if (ret != 0) {
- printf(
- "Failed audit_triggers(AUDIT_TRIGGER_LOW_SPACE): %d\n", ret);
- }
- }
- }
-
- /* Check if the current log file is full; if so, call for
- * a log rotate. This is not an exact comparison; we may
- * write some records over the limit. If that's not
- * acceptable, then add a fudge factor here.
- */
- if ((audit_fstat.af_filesz != 0) &&
- (audit_file_rotate_wait == 0) &&
- (vattr.va_size >= audit_fstat.af_filesz)) {
- audit_file_rotate_wait = 1;
- ret = send_trigger(AUDIT_TRIGGER_OPEN_NEW);
- if (ret != 0) {
- printf(
- "Failed audit_triggers(AUDIT_TRIGGER_OPEN_NEW): %d\n", ret);
- /* XXX what to do here? */
- }
- }
-
- /*
- * If the estimated amount of audit data in the audit event queue
- * (plus records allocated but not yet queued) has reached the
- * amount of free space on the disk, then we need to go into an
- * audit fail stop state, in which we do not permit the
- * allocation/committing of any new audit records. We continue to
- * process packets but don't allow any activities that might
- * generate new records. In the future, we might want to detect
- * when space is available again and allow operation to continue,
- * but this behavior is sufficient to meet fail stop requirements
- * in CAPP.
- */
- if (audit_fail_stop &&
- (unsigned long)
- ((audit_q_len + audit_pre_q_len + 1) * MAX_AUDIT_RECORD_SIZE) /
- mnt_stat->f_bsize >= (unsigned long)(mnt_stat->f_bfree)) {
- printf(
- "audit_worker: free space below size of audit queue, failing stop\n");
- audit_in_failure = 1;
- }
-
- /*
- * If there is a user audit record attached to the kernel record,
- * then write the user record.
- */
- /* XXX Need to decide a few things here: IF the user audit
- * record is written, but the write of the kernel record fails,
- * what to do? Should the kernel record come before or after the
- * user record? For now, we write the user record first, and
- * we ignore errors.
- */
- if (ar->k_ar_commit & AR_COMMIT_USER) {
- ret = vn_rdwr(UIO_WRITE, vp, (void *)ar->k_udata, ar->k_ulen,
- (off_t)0, UIO_SYSSPACE, IO_APPEND|IO_UNIT, cred, NULL,
- NULL, td);
- if (ret)
- goto out;
- }
-
- /*
- * Convert the internal kernel record to BSM format and write it
- * out if everything's OK.
- */
- if (!(ar->k_ar_commit & AR_COMMIT_KERNEL)) {
- ret = 0;
- goto out;
- }
-
- /*
- * XXXAUDIT: Should we actually allow this conversion to fail? With
- * sleeping memory allocation and invariants checks, perhaps not.
- */
- ret = kaudit_to_bsm(ar, &bsm);
- if (ret == BSM_NOAUDIT) {
- ret = 0;
- goto out;
- }
-
- /*
- * XXX: We drop the record on BSM conversion failure, but really
- * this is an assertion failure.
- */
- if (ret == BSM_FAILURE) {
- AUDIT_PRINTF(("BSM conversion failure\n"));
- ret = EINVAL;
- goto out;
- }
-
- /*
- * XXX
- * We should break the write functionality away from the BSM record
- * generation and have the BSM generation done before this function
- * is called. This function will then take the BSM record as a
- * parameter.
- */
- ret = (vn_rdwr(UIO_WRITE, vp, (void *)bsm->data, bsm->len,
- (off_t)0, UIO_SYSSPACE, IO_APPEND|IO_UNIT, cred, NULL, NULL, td));
-
- kau_free(bsm);
-
-out:
- /*
- * When we're done processing the current record, we have to
- * check to see if we're in a failure mode, and if so, whether
- * this was the last record left to be drained. If we're done
- * draining, then we fsync the vnode and panic.
- */
- if (audit_in_failure &&
- audit_q_len == 0 && audit_pre_q_len == 0) {
- VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, td);
- (void)VOP_FSYNC(vp, MNT_WAIT, td);
- VOP_UNLOCK(vp, 0, td);
- panic("Audit store overflow; record queue drained.");
- }
-
- VFS_UNLOCK_GIANT(vfslocked);
-
- return (ret);
-}
-
-/*
- * The audit_worker thread is responsible for watching the event queue,
- * dequeueing records, converting them to BSM format, and committing them to
- * disk. In order to minimize lock thrashing, records are dequeued in sets
- * to a thread-local work queue. In addition, the audit_work performs the
- * actual exchange of audit log vnode pointer, as audit_vp is a thread-local
- * variable.
- */
-static void
-audit_worker(void *arg)
-{
- int do_replacement_signal, error;
- TAILQ_HEAD(, kaudit_record) ar_worklist;
- struct kaudit_record *ar;
- struct vnode *audit_vp, *old_vp;
- int vfslocked;
-
- struct ucred *audit_cred, *old_cred;
- struct thread *audit_td;
-
- AUDIT_PRINTF(("audit_worker starting\n"));
-
- /*
- * These are thread-local variables requiring no synchronization.
- */
- TAILQ_INIT(&ar_worklist);
- audit_cred = NULL;
- audit_td = curthread;
- audit_vp = NULL;
-
- mtx_lock(&audit_mtx);
- while (1) {
- /*
- * First priority: replace the audit log target if requested.
- * Accessing the vnode here requires dropping the audit_mtx;
- * in case another replacement was scheduled while the mutex
- * was released, we loop.
- *
- * XXX It could well be we should drain existing records
- * first to ensure that the timestamps and ordering
- * are right.
- */
- do_replacement_signal = 0;
- while (audit_replacement_flag != 0) {
- old_cred = audit_cred;
- old_vp = audit_vp;
- audit_cred = audit_replacement_cred;
- audit_vp = audit_replacement_vp;
- audit_replacement_cred = NULL;
- audit_replacement_vp = NULL;
- audit_replacement_flag = 0;
-
- audit_enabled = (audit_vp != NULL);
-
- /*
- * XXX: What to do about write failures here?
- */
- if (old_vp != NULL) {
- AUDIT_PRINTF(("Closing old audit file\n"));
- mtx_unlock(&audit_mtx);
- vfslocked = VFS_LOCK_GIANT(old_vp->v_mount);
- vn_close(old_vp, audit_close_flags, old_cred,
- audit_td);
- VFS_UNLOCK_GIANT(vfslocked);
- crfree(old_cred);
- mtx_lock(&audit_mtx);
- old_cred = NULL;
- old_vp = NULL;
- AUDIT_PRINTF(("Audit file closed\n"));
- }
- if (audit_vp != NULL) {
- AUDIT_PRINTF(("Opening new audit file\n"));
- }
- do_replacement_signal = 1;
- }
- /*
- * Signal that replacement have occurred to wake up and
- * start any other replacements started in parallel. We can
- * continue about our business in the mean time. We
- * broadcast so that both new replacements can be inserted,
- * but also so that the source(s) of replacement can return
- * successfully.
- */
- if (do_replacement_signal)
- cv_broadcast(&audit_replacement_cv);
-
- /*
- * Next, check to see if we have any records to drain into
- * the vnode. If not, go back to waiting for an event.
- */
- if (TAILQ_EMPTY(&audit_q)) {
- AUDIT_PRINTF(("audit_worker waiting\n"));
- cv_wait(&audit_cv, &audit_mtx);
- AUDIT_PRINTF(("audit_worker woken up\n"));
- AUDIT_PRINTF(("audit_worker: new vp = %p; value of flag %d\n",
- audit_replacement_vp, audit_replacement_flag));
- continue;
- }
-
- /*
- * If we have records, but there's no active vnode to
- * write to, drain the record queue. Generally, we
- * prevent the unnecessary allocation of records
- * elsewhere, but we need to allow for races between
- * conditional allocation and queueing. Go back to
- * waiting when we're done.
- *
- * XXX: We go out of our way to avoid calling audit_free()
- * with the audit_mtx held, to avoid a lock order reversal
- * as free() may grab Giant. This should be fixed at
- * some point.
- */
- if (audit_vp == NULL) {
- while ((ar = TAILQ_FIRST(&audit_q))) {
- TAILQ_REMOVE(&audit_q, ar, k_q);
- audit_q_len--;
- if (audit_q_len <= audit_qctrl.aq_lowater)
- cv_broadcast(&audit_commit_cv);
-
- TAILQ_INSERT_TAIL(&ar_worklist, ar, k_q);
- }
- mtx_unlock(&audit_mtx);
- while ((ar = TAILQ_FIRST(&ar_worklist))) {
- TAILQ_REMOVE(&ar_worklist, ar, k_q);
- audit_free(ar);
- }
- mtx_lock(&audit_mtx);
- continue;
- }
-
- /*
- * We have both records to write and an active vnode
- * to write to. Dequeue a record, and start the write.
- * Eventually, it might make sense to dequeue several
- * records and perform our own clustering, if the lower
- * layers aren't doing it automatically enough.
- *
- * XXX: We go out of our way to avoid calling audit_free()
- * with the audit_mtx held, to avoid a lock order reversal
- * as free() may grab Giant. This should be fixed at
- * some point.
- *
- * XXXAUDIT: free() no longer grabs Giant.
- */
- while ((ar = TAILQ_FIRST(&audit_q))) {
- TAILQ_REMOVE(&audit_q, ar, k_q);
- audit_q_len--;
- if (audit_q_len <= audit_qctrl.aq_lowater)
- cv_broadcast(&audit_commit_cv);
-
- TAILQ_INSERT_TAIL(&ar_worklist, ar, k_q);
- }
-
- mtx_unlock(&audit_mtx);
- while ((ar = TAILQ_FIRST(&ar_worklist))) {
- TAILQ_REMOVE(&ar_worklist, ar, k_q);
- if (audit_vp != NULL) {
- error = audit_record_write(audit_vp, ar,
- audit_cred, audit_td);
- if (error && audit_panic_on_write_fail)
- panic("audit_worker: write error %d\n",
- error);
- else if (error)
- printf("audit_worker: write error %d\n",
- error);
- }
- audit_free(ar);
- }
- mtx_lock(&audit_mtx);
- }
-}
-
-/*
- * Initialize the Audit subsystem: configuration state, work queue,
- * synchronization primitives, worker thread, and trigger device node. Also
- * call into the BSM assembly code to initialize it.
- */
-static void
-audit_init(void)
+void
+audit_trigger_init(void)
{
- int error;
-
- printf("Security auditing service present\n");
- TAILQ_INIT(&audit_q);
- audit_q_len = 0;
- audit_pre_q_len = 0;
- audit_enabled = 0;
- audit_suspended = 0;
- audit_replacement_cred = NULL;
- audit_replacement_flag = 0;
- audit_file_rotate_wait = 0;
- audit_replacement_vp = NULL;
- audit_fstat.af_filesz = 0; /* '0' means unset, unbounded */
- audit_fstat.af_currsz = 0;
- audit_qctrl.aq_hiwater = AQ_HIWATER;
- audit_qctrl.aq_lowater = AQ_LOWATER;
- audit_qctrl.aq_bufsz = AQ_BUFSZ;
- audit_qctrl.aq_minfree = AU_FS_MINFREE;
-
- mtx_init(&audit_mtx, "audit_mtx", NULL, MTX_DEF);
- cv_init(&audit_cv, "audit_cv");
- cv_init(&audit_replacement_cv, "audit_replacement_cv");
- cv_init(&audit_commit_cv, "audit_commit_cv");
- cv_init(&audit_fail_cv, "audit_fail_cv");
-
- /* Initialize the BSM audit subsystem. */
- kau_init();
TAILQ_INIT(&trigger_list);
-
- /* Register shutdown handler. */
- EVENTHANDLER_REGISTER(shutdown_pre_sync, audit_shutdown, NULL,
- SHUTDOWN_PRI_FIRST);
-
- error = kthread_create(audit_worker, NULL, &audit_thread, RFHIGHPID,
- 0, "audit_worker");
- if (error != 0)
- panic("audit_init: kthread_create returned %d", error);
+ mtx_init(&audit_trigger_mtx, "audit_trigger_mtx", NULL, MTX_DEF);
}
static void
-audit_cdev_init(void *unused)
+audit_trigger_cdev_init(void *unused)
{
/* Create the special device file */
@@ -780,1768 +164,5 @@
AUDITDEV_FILENAME);
}
-SYSINIT(audit_init, SI_SUB_AUDIT, SI_ORDER_FIRST, audit_init, NULL)
-SYSINIT(audit_cdev_init, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, audit_cdev_init,
- NULL)
-
-/*
- * audit_rotate_vnode() is called by a user or kernel thread to configure or
- * de-configure auditing on a vnode. The arguments are the replacement
- * credential and vnode to substitute for the current credential and vnode,
- * if any. If either is set to NULL, both should be NULL, and this is used
- * to indicate that audit is being disabled. The real work is done in the
- * audit_worker thread, but audit_rotate_vnode() waits synchronously for that
- * to complete.
- *
- * The vnode should be referenced and opened by the caller. The credential
- * should be referenced. audit_rotate_vnode() will own both references as of
- * this call, so the caller should not release either.
- *
- * XXXAUDIT: Review synchronize communication logic. Really, this is a
- * message queue of depth 1.
- *
- * XXXAUDIT: Enhance the comments below to indicate that we are basically
- * acquiring ownership of the communications queue, inserting our message,
- * and waiting for an acknowledgement.
- */
-static void
-audit_rotate_vnode(struct ucred *cred, struct vnode *vp)
-{
-
- /*
- * If other parallel log replacements have been requested, we wait
- * until they've finished before continuing.
- */
- mtx_lock(&audit_mtx);
- while (audit_replacement_flag != 0) {
- AUDIT_PRINTF(("audit_rotate_vnode: sleeping to wait for "
- "flag\n"));
- cv_wait(&audit_replacement_cv, &audit_mtx);
- AUDIT_PRINTF(("audit_rotate_vnode: woken up (flag %d)\n",
- audit_replacement_flag));
- }
- audit_replacement_cred = cred;
- audit_replacement_flag = 1;
- audit_replacement_vp = vp;
-
- /*
- * Wake up the audit worker to perform the exchange once we
- * release the mutex.
- */
- cv_signal(&audit_cv);
-
- /*
- * Wait for the audit_worker to broadcast that a replacement has
- * taken place; we know that once this has happened, our vnode
- * has been replaced in, so we can return successfully.
- */
- AUDIT_PRINTF(("audit_rotate_vnode: waiting for news of "
- "replacement\n"));
- cv_wait(&audit_replacement_cv, &audit_mtx);
- AUDIT_PRINTF(("audit_rotate_vnode: change acknowledged by "
- "audit_worker (flag " "now %d)\n", audit_replacement_flag));
- mtx_unlock(&audit_mtx);
-
- /* XXX Need to figure out how the kernel->userspace file full
- * signalling will take place.
- *
- * XXXAUDIT: This comment may now be obsolete.
- */
- audit_file_rotate_wait = 0; /* We can now request another rotation */
-}
-
-/*
- * Drain the audit queue and close the log at shutdown. Note that this can
- * be called both from the system shutdown path and also from audit
- * configuration syscalls, so 'arg' and 'howto' are ignored.
- */
-static void
-audit_shutdown(void *arg, int howto)
-{
-
- audit_rotate_vnode(NULL, NULL);
-}
-
-/*
- * Return the current thread's audit record, if any.
- */
-static __inline__ struct kaudit_record *
-currecord(void)
-{
-
- return (curthread->td_ar);
-}
-
-/**********************************
- * Begin system calls. *
- **********************************/
-/*
- * MPSAFE
- *
- * System call to allow a user space application to submit a BSM audit
- * record to the kernel for inclusion in the audit log. This function
- * does little verification on the audit record that is submitted.
- *
- * XXXAUDIT: Audit preselection for user records does not currently
- * work, since we pre-select only based on the AUE_audit event type,
- * not the event type submitted as part of the user audit data.
- */
-/* ARGSUSED */
-int
-audit(struct thread *td, struct audit_args *uap)
-{
- int error;
- void * rec;
- struct kaudit_record *ar;
-
- error = suser(td);
- if (error)
- return (error);
-
- if ((uap->length <= 0) || (uap->length > audit_qctrl.aq_bufsz))
- return (EINVAL);
-
- ar = currecord();
-
- /* If there's no current audit record (audit() itself not audited)
- * commit the user audit record.
- */
- if (ar == NULL) {
-
- /* This is not very efficient; we're required to allocate
- * a complete kernel audit record just so the user record
- * can tag along.
- *
- * XXXAUDIT: Maybe AUE_AUDIT in the system call context and
- * special pre-select handling?
- */
- td->td_ar = audit_new(AUE_NULL, td);
- if (td->td_ar == NULL)
- return (ENOTSUP);
- ar = td->td_ar;
- }
-
- if (uap->length > MAX_AUDIT_RECORD_SIZE)
- return (EINVAL);
-
- rec = malloc(uap->length, M_AUDIT, M_WAITOK);
-
- error = copyin(uap->record, rec, uap->length);
- if (error)
- goto free_out;
-
- /* Verify the record */
- if (bsm_rec_verify(rec) == 0) {
- error = EINVAL;
- goto free_out;
- }
-
- /* Attach the user audit record to the kernel audit record. Because
- * this system call is an auditable event, we will write the user
- * record along with the record for this audit event.
- *
- * XXXAUDIT: KASSERT appropriate starting values of k_udata, k_ulen,
- * k_ar_commit & AR_COMMIT_USER?
- */
- ar->k_udata = rec;
- ar->k_ulen = uap->length;
- ar->k_ar_commit |= AR_COMMIT_USER;
- return (0);
-
-free_out:
- /* audit_syscall_exit() will free the audit record on the thread
- * even if we allocated it above.
- */
- free(rec, M_AUDIT);
- return (error);
-}
-
-/*
- * MPSAFE
- *
- * System call to manipulate auditing.
- */
-/* ARGSUSED */
-int
>>> TRUNCATED FOR MAIL (1000 lines) <<<
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