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- /*-
- * SPDX-License-Identifier: BSD-3-Clause
- *
- * Copyright (c) 1999-2005 Apple Inc.
- * Copyright (c) 2006-2007, 2016-2018 Robert N. M. Watson
- * All rights reserved.
- *
- * Portions of this software were developed by BAE Systems, the University of
- * Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
- * contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
- * Computing (TC) research program.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of Apple Inc. ("Apple") nor the names of
- * its contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
- * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
- * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
- #include <sys/param.h>
- #include <sys/condvar.h>
- #include <sys/conf.h>
- #include <sys/eventhandler.h>
- #include <sys/file.h>
- #include <sys/filedesc.h>
- #include <sys/fcntl.h>
- #include <sys/ipc.h>
- #include <sys/jail.h>
- #include <sys/kernel.h>
- #include <sys/kthread.h>
- #include <sys/malloc.h>
- #include <sys/mount.h>
- #include <sys/namei.h>
- #include <sys/priv.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/sysctl.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 <bsm/audit.h>
- #include <bsm/audit_internal.h>
- #include <bsm/audit_kevents.h>
- #include <netinet/in.h>
- #include <netinet/in_pcb.h>
- #include <security/audit/audit.h>
- #include <security/audit/audit_private.h>
- #include <vm/uma.h>
- FEATURE(audit, "BSM audit support");
- static uma_zone_t audit_record_zone;
- static MALLOC_DEFINE(M_AUDITCRED, "audit_cred", "Audit cred storage");
- MALLOC_DEFINE(M_AUDITDATA, "audit_data", "Audit data storage");
- MALLOC_DEFINE(M_AUDITPATH, "audit_path", "Audit path storage");
- MALLOC_DEFINE(M_AUDITTEXT, "audit_text", "Audit text storage");
- MALLOC_DEFINE(M_AUDITGIDSET, "audit_gidset", "Audit GID set storage");
- static SYSCTL_NODE(_security, OID_AUTO, audit, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
- "TrustedBSD audit controls");
- /*
- * Audit control settings that are set/read by system calls and are hence
- * non-static.
- *
- * Define the audit control flags.
- */
- int audit_trail_enabled;
- int audit_trail_suspended;
- #ifdef KDTRACE_HOOKS
- u_int audit_dtrace_enabled;
- #endif
- bool __read_frequently audit_syscalls_enabled;
- /*
- * 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?
- */
- int audit_panic_on_write_fail;
- int audit_fail_stop;
- int audit_argv;
- int audit_arge;
- /*
- * Are we currently "failing stop" due to out of disk space?
- */
- int audit_in_failure;
- /*
- * Global audit statistics.
- */
- struct audit_fstat audit_fstat;
- /*
- * Preselection mask for non-attributable events.
- */
- struct au_mask audit_nae_mask;
- /*
- * Mutex to protect global variables shared between various threads and
- * processes.
- */
- 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.
- */
- struct kaudit_queue audit_q;
- int audit_q_len;
- int audit_pre_q_len;
- /*
- * Audit queue control settings (minimum free, low/high water marks, etc.)
- */
- struct au_qctrl audit_qctrl;
- /*
- * 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.
- */
- struct cv audit_worker_cv;
- /*
- * Condition variable to flag when crossing the low watermark, meaning that
- * threads blocked due to hitting the high watermark can wake up and continue
- * to commit records.
- */
- struct cv audit_watermark_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;
- /*
- * Optional DTrace audit provider support: function pointers for preselection
- * and commit events.
- */
- #ifdef KDTRACE_HOOKS
- void *(*dtaudit_hook_preselect)(au_id_t auid, au_event_t event,
- au_class_t class);
- int (*dtaudit_hook_commit)(struct kaudit_record *kar, au_id_t auid,
- au_event_t event, au_class_t class, int sorf);
- void (*dtaudit_hook_bsm)(struct kaudit_record *kar, au_id_t auid,
- au_event_t event, au_class_t class, int sorf,
- void *bsm_data, size_t bsm_lenlen);
- #endif
- /*
- * Kernel audit information. This will store the current audit address
- * or host information that the kernel will use when it's generating
- * audit records. This data is modified by the A_GET{SET}KAUDIT auditon(2)
- * command.
- */
- static struct auditinfo_addr audit_kinfo;
- static struct rwlock audit_kinfo_lock;
- #define KINFO_LOCK_INIT() rw_init(&audit_kinfo_lock, \
- "audit_kinfo_lock")
- #define KINFO_RLOCK() rw_rlock(&audit_kinfo_lock)
- #define KINFO_WLOCK() rw_wlock(&audit_kinfo_lock)
- #define KINFO_RUNLOCK() rw_runlock(&audit_kinfo_lock)
- #define KINFO_WUNLOCK() rw_wunlock(&audit_kinfo_lock)
- /*
- * Check various policies to see if we should enable system-call audit hooks.
- * Note that despite the mutex being held, we want to assign a value exactly
- * once, as checks of the flag are performed lock-free for performance
- * reasons. The mutex is used to get a consistent snapshot of policy state --
- * e.g., safely accessing the two audit_trail flags.
- */
- void
- audit_syscalls_enabled_update(void)
- {
- mtx_lock(&audit_mtx);
- #ifdef KDTRACE_HOOKS
- if (audit_dtrace_enabled)
- audit_syscalls_enabled = true;
- else {
- #endif
- if (audit_trail_enabled && !audit_trail_suspended)
- audit_syscalls_enabled = true;
- else
- audit_syscalls_enabled = false;
- #ifdef KDTRACE_HOOKS
- }
- #endif
- mtx_unlock(&audit_mtx);
- }
- void
- audit_set_kinfo(struct auditinfo_addr *ak)
- {
- KASSERT(ak->ai_termid.at_type == AU_IPv4 ||
- ak->ai_termid.at_type == AU_IPv6,
- ("audit_set_kinfo: invalid address type"));
- KINFO_WLOCK();
- audit_kinfo = *ak;
- KINFO_WUNLOCK();
- }
- void
- audit_get_kinfo(struct auditinfo_addr *ak)
- {
- KASSERT(audit_kinfo.ai_termid.at_type == AU_IPv4 ||
- audit_kinfo.ai_termid.at_type == AU_IPv6,
- ("audit_set_kinfo: invalid address type"));
- KINFO_RLOCK();
- *ak = audit_kinfo;
- KINFO_RUNLOCK();
- }
- /*
- * Construct an audit record for the passed thread.
- */
- static int
- audit_record_ctor(void *mem, int size, void *arg, int flags)
- {
- struct kaudit_record *ar;
- struct thread *td;
- struct ucred *cred;
- struct prison *pr;
- KASSERT(sizeof(*ar) == size, ("audit_record_ctor: wrong size"));
- td = arg;
- ar = mem;
- bzero(ar, sizeof(*ar));
- ar->k_ar.ar_magic = AUDIT_RECORD_MAGIC;
- nanotime(&ar->k_ar.ar_starttime);
- /*
- * Export the subject credential.
- */
- cred = td->td_ucred;
- cru2x(cred, &ar->k_ar.ar_subj_cred);
- ar->k_ar.ar_subj_ruid = cred->cr_ruid;
- ar->k_ar.ar_subj_rgid = cred->cr_rgid;
- ar->k_ar.ar_subj_egid = cred->cr_groups[0];
- ar->k_ar.ar_subj_auid = cred->cr_audit.ai_auid;
- ar->k_ar.ar_subj_asid = cred->cr_audit.ai_asid;
- ar->k_ar.ar_subj_pid = td->td_proc->p_pid;
- ar->k_ar.ar_subj_amask = cred->cr_audit.ai_mask;
- ar->k_ar.ar_subj_term_addr = cred->cr_audit.ai_termid;
- /*
- * If this process is jailed, make sure we capture the name of the
- * jail so we can use it to generate a zonename token when we covert
- * this record to BSM.
- */
- if (jailed(cred)) {
- pr = cred->cr_prison;
- (void) strlcpy(ar->k_ar.ar_jailname, pr->pr_name,
- sizeof(ar->k_ar.ar_jailname));
- } else
- ar->k_ar.ar_jailname[0] = '\0';
- return (0);
- }
- static void
- audit_record_dtor(void *mem, int size, void *arg)
- {
- struct kaudit_record *ar;
- KASSERT(sizeof(*ar) == size, ("audit_record_dtor: wrong size"));
- ar = mem;
- if (ar->k_ar.ar_arg_upath1 != NULL)
- free(ar->k_ar.ar_arg_upath1, M_AUDITPATH);
- if (ar->k_ar.ar_arg_upath2 != NULL)
- free(ar->k_ar.ar_arg_upath2, M_AUDITPATH);
- if (ar->k_ar.ar_arg_text != NULL)
- free(ar->k_ar.ar_arg_text, M_AUDITTEXT);
- if (ar->k_udata != NULL)
- free(ar->k_udata, M_AUDITDATA);
- if (ar->k_ar.ar_arg_argv != NULL)
- free(ar->k_ar.ar_arg_argv, M_AUDITTEXT);
- if (ar->k_ar.ar_arg_envv != NULL)
- free(ar->k_ar.ar_arg_envv, M_AUDITTEXT);
- if (ar->k_ar.ar_arg_groups.gidset != NULL)
- free(ar->k_ar.ar_arg_groups.gidset, M_AUDITGIDSET);
- }
- /*
- * 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)
- {
- audit_trail_enabled = 0;
- audit_trail_suspended = 0;
- audit_syscalls_enabled = false;
- audit_panic_on_write_fail = 0;
- audit_fail_stop = 0;
- audit_in_failure = 0;
- audit_argv = 0;
- audit_arge = 0;
- audit_fstat.af_filesz = 0; /* '0' means unset, unbounded. */
- audit_fstat.af_currsz = 0;
- audit_nae_mask.am_success = 0;
- audit_nae_mask.am_failure = 0;
- TAILQ_INIT(&audit_q);
- audit_q_len = 0;
- audit_pre_q_len = 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;
- audit_kinfo.ai_termid.at_type = AU_IPv4;
- audit_kinfo.ai_termid.at_addr[0] = INADDR_ANY;
- mtx_init(&audit_mtx, "audit_mtx", NULL, MTX_DEF);
- KINFO_LOCK_INIT();
- cv_init(&audit_worker_cv, "audit_worker_cv");
- cv_init(&audit_watermark_cv, "audit_watermark_cv");
- cv_init(&audit_fail_cv, "audit_fail_cv");
- audit_record_zone = uma_zcreate("audit_record",
- sizeof(struct kaudit_record), audit_record_ctor,
- audit_record_dtor, NULL, NULL, UMA_ALIGN_PTR, 0);
- /* First initialisation of audit_syscalls_enabled. */
- audit_syscalls_enabled_update();
- /* Initialize the BSM audit subsystem. */
- kau_init();
- audit_trigger_init();
- /* Register shutdown handler. */
- EVENTHANDLER_REGISTER(shutdown_pre_sync, audit_shutdown, NULL,
- SHUTDOWN_PRI_FIRST);
- /* Start audit worker thread. */
- audit_worker_init();
- }
- SYSINIT(audit_init, SI_SUB_AUDIT, SI_ORDER_FIRST, audit_init, NULL);
- /*
- * 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.
- *
- * XXXRW: In FreeBSD 7.x and 8.x, this fails to wait for the record queue to
- * drain before returning, which could lead to lost records on shutdown.
- */
- void
- audit_shutdown(void *arg, int howto)
- {
- audit_rotate_vnode(NULL, NULL);
- }
- /*
- * Return the current thread's audit record, if any.
- */
- struct kaudit_record *
- currecord(void)
- {
- return (curthread->td_ar);
- }
- /*
- * XXXAUDIT: Shouldn't there be logic here to sleep waiting on available
- * pre_q space, suspending the system call until there is room?
- */
- struct kaudit_record *
- audit_new(int event, struct thread *td)
- {
- struct kaudit_record *ar;
- /*
- * Note: the number of outstanding uncommitted audit records is
- * limited to the number of concurrent threads servicing system calls
- * in the kernel.
- */
- ar = uma_zalloc_arg(audit_record_zone, td, M_WAITOK);
- ar->k_ar.ar_event = event;
- mtx_lock(&audit_mtx);
- audit_pre_q_len++;
- mtx_unlock(&audit_mtx);
- return (ar);
- }
- void
- audit_free(struct kaudit_record *ar)
- {
- uma_zfree(audit_record_zone, ar);
- }
- void
- audit_commit(struct kaudit_record *ar, int error, int retval)
- {
- au_event_t event;
- au_class_t class;
- au_id_t auid;
- int sorf;
- struct au_mask *aumask;
- if (ar == NULL)
- return;
- ar->k_ar.ar_errno = error;
- ar->k_ar.ar_retval = retval;
- nanotime(&ar->k_ar.ar_endtime);
- /*
- * Decide whether to commit the audit record by checking the error
- * value from the system call and using the appropriate audit mask.
- */
- if (ar->k_ar.ar_subj_auid == AU_DEFAUDITID)
- aumask = &audit_nae_mask;
- else
- aumask = &ar->k_ar.ar_subj_amask;
- if (error)
- sorf = AU_PRS_FAILURE;
- else
- sorf = AU_PRS_SUCCESS;
- /*
- * syscalls.master sometimes contains a prototype event number, which
- * we will transform into a more specific event number now that we
- * have more complete information gathered during the system call.
- */
- switch(ar->k_ar.ar_event) {
- case AUE_OPEN_RWTC:
- ar->k_ar.ar_event = audit_flags_and_error_to_openevent(
- ar->k_ar.ar_arg_fflags, error);
- break;
- case AUE_OPENAT_RWTC:
- ar->k_ar.ar_event = audit_flags_and_error_to_openatevent(
- ar->k_ar.ar_arg_fflags, error);
- break;
- case AUE_SYSCTL:
- ar->k_ar.ar_event = audit_ctlname_to_sysctlevent(
- ar->k_ar.ar_arg_ctlname, ar->k_ar.ar_valid_arg);
- break;
- case AUE_AUDITON:
- /* Convert the auditon() command to an event. */
- ar->k_ar.ar_event = auditon_command_event(ar->k_ar.ar_arg_cmd);
- break;
- case AUE_MSGSYS:
- if (ARG_IS_VALID(ar, ARG_SVIPC_WHICH))
- ar->k_ar.ar_event =
- audit_msgsys_to_event(ar->k_ar.ar_arg_svipc_which);
- break;
- case AUE_SEMSYS:
- if (ARG_IS_VALID(ar, ARG_SVIPC_WHICH))
- ar->k_ar.ar_event =
- audit_semsys_to_event(ar->k_ar.ar_arg_svipc_which);
- break;
- case AUE_SHMSYS:
- if (ARG_IS_VALID(ar, ARG_SVIPC_WHICH))
- ar->k_ar.ar_event =
- audit_shmsys_to_event(ar->k_ar.ar_arg_svipc_which);
- break;
- }
- auid = ar->k_ar.ar_subj_auid;
- event = ar->k_ar.ar_event;
- class = au_event_class(event);
- ar->k_ar_commit |= AR_COMMIT_KERNEL;
- if (au_preselect(event, class, aumask, sorf) != 0)
- ar->k_ar_commit |= AR_PRESELECT_TRAIL;
- if (audit_pipe_preselect(auid, event, class, sorf,
- ar->k_ar_commit & AR_PRESELECT_TRAIL) != 0)
- ar->k_ar_commit |= AR_PRESELECT_PIPE;
- #ifdef KDTRACE_HOOKS
- /*
- * Expose the audit record to DTrace, both to allow the "commit" probe
- * to fire if it's desirable, and also to allow a decision to be made
- * about later firing with BSM in the audit worker.
- */
- if (dtaudit_hook_commit != NULL) {
- if (dtaudit_hook_commit(ar, auid, event, class, sorf) != 0)
- ar->k_ar_commit |= AR_PRESELECT_DTRACE;
- }
- #endif
- if ((ar->k_ar_commit & (AR_PRESELECT_TRAIL | AR_PRESELECT_PIPE |
- AR_PRESELECT_USER_TRAIL | AR_PRESELECT_USER_PIPE |
- AR_PRESELECT_DTRACE)) == 0) {
- mtx_lock(&audit_mtx);
- audit_pre_q_len--;
- mtx_unlock(&audit_mtx);
- audit_free(ar);
- return;
- }
- /*
- * Note: it could be that some records initiated while audit was
- * enabled should still be committed?
- *
- * NB: The check here is not for audit_syscalls because any
- * DTrace-related obligations have been fulfilled above -- we're just
- * down to the trail and pipes now.
- */
- mtx_lock(&audit_mtx);
- if (audit_trail_suspended || !audit_trail_enabled) {
- audit_pre_q_len--;
- mtx_unlock(&audit_mtx);
- audit_free(ar);
- return;
- }
- /*
- * Constrain the number of committed audit records based on the
- * configurable parameter.
- */
- while (audit_q_len >= audit_qctrl.aq_hiwater)
- cv_wait(&audit_watermark_cv, &audit_mtx);
- TAILQ_INSERT_TAIL(&audit_q, ar, k_q);
- audit_q_len++;
- audit_pre_q_len--;
- cv_signal(&audit_worker_cv);
- mtx_unlock(&audit_mtx);
- }
- /*
- * audit_syscall_enter() is called on entry to each system call. It is
- * responsible for deciding whether or not to audit the call (preselection),
- * and if so, allocating a per-thread audit record. audit_new() will fill in
- * basic thread/credential properties.
- *
- * This function will be entered only if audit_syscalls_enabled was set in the
- * macro wrapper for this function. It could be cleared by the time this
- * function runs, but that is an acceptable race.
- */
- void
- audit_syscall_enter(unsigned short code, struct thread *td)
- {
- struct au_mask *aumask;
- #ifdef KDTRACE_HOOKS
- void *dtaudit_state;
- #endif
- au_class_t class;
- au_event_t event;
- au_id_t auid;
- int record_needed;
- KASSERT(td->td_ar == NULL, ("audit_syscall_enter: td->td_ar != NULL"));
- KASSERT((td->td_pflags & TDP_AUDITREC) == 0,
- ("audit_syscall_enter: TDP_AUDITREC set"));
- /*
- * In FreeBSD, each ABI has its own system call table, and hence
- * mapping of system call codes to audit events. Convert the code to
- * an audit event identifier using the process system call table
- * reference. In Darwin, there's only one, so we use the global
- * symbol for the system call table. No audit record is generated
- * for bad system calls, as no operation has been performed.
- */
- if (code >= td->td_proc->p_sysent->sv_size)
- return;
- event = td->td_proc->p_sysent->sv_table[code].sy_auevent;
- if (event == AUE_NULL)
- return;
- /*
- * Check which audit mask to use; either the kernel non-attributable
- * event mask or the process audit mask.
- */
- auid = td->td_ucred->cr_audit.ai_auid;
- if (auid == AU_DEFAUDITID)
- aumask = &audit_nae_mask;
- else
- aumask = &td->td_ucred->cr_audit.ai_mask;
- /*
- * Determine whether trail or pipe preselection would like an audit
- * record allocated for this system call.
- */
- class = au_event_class(event);
- if (au_preselect(event, class, aumask, AU_PRS_BOTH)) {
- /*
- * If we're out of space and need to suspend unprivileged
- * processes, do that here rather than trying to allocate
- * another audit record.
- *
- * Note: we might wish to be able to continue here in the
- * future, if the system recovers. That should be possible
- * by means of checking the condition in a loop around
- * cv_wait(). It might be desirable to reevaluate whether an
- * audit record is still required for this event by
- * re-calling au_preselect().
- */
- if (audit_in_failure &&
- priv_check(td, PRIV_AUDIT_FAILSTOP) != 0) {
- cv_wait(&audit_fail_cv, &audit_mtx);
- panic("audit_failing_stop: thread continued");
- }
- record_needed = 1;
- } else if (audit_pipe_preselect(auid, event, class, AU_PRS_BOTH, 0)) {
- record_needed = 1;
- } else {
- record_needed = 0;
- }
- /*
- * After audit trails and pipes have made their policy choices, DTrace
- * may request that records be generated as well. This is a slightly
- * complex affair, as the DTrace audit provider needs the audit
- * framework to maintain some state on the audit record, which has not
- * been allocated at the point where the decision has to be made.
- * This hook must run even if we are not changing the decision, as
- * DTrace may want to stick event state onto a record we were going to
- * produce due to the trail or pipes. The event state returned by the
- * DTrace provider must be safe without locks held between here and
- * below -- i.e., dtaudit_state must must refer to stable memory.
- */
- #ifdef KDTRACE_HOOKS
- dtaudit_state = NULL;
- if (dtaudit_hook_preselect != NULL) {
- dtaudit_state = dtaudit_hook_preselect(auid, event, class);
- if (dtaudit_state != NULL)
- record_needed = 1;
- }
- #endif
- /*
- * If a record is required, allocate it and attach it to the thread
- * for use throughout the system call. Also attach DTrace state if
- * required.
- *
- * XXXRW: If we decide to reference count the evname_elem underlying
- * dtaudit_state, we will need to free here if no record is allocated
- * or allocatable.
- */
- if (record_needed) {
- td->td_ar = audit_new(event, td);
- if (td->td_ar != NULL) {
- td->td_pflags |= TDP_AUDITREC;
- #ifdef KDTRACE_HOOKS
- td->td_ar->k_dtaudit_state = dtaudit_state;
- #endif
- }
- } else
- td->td_ar = NULL;
- }
- /*
- * audit_syscall_exit() is called from the return of every system call, or in
- * the event of exit1(), during the execution of exit1(). It is responsible
- * for committing the audit record, if any, along with return condition.
- */
- void
- audit_syscall_exit(int error, struct thread *td)
- {
- int retval;
- /*
- * Commit the audit record as desired; once we pass the record into
- * audit_commit(), the memory is owned by the audit subsystem. The
- * return value from the system call is stored on the user thread.
- * If there was an error, the return value is set to -1, imitating
- * the behavior of the cerror routine.
- */
- if (error)
- retval = -1;
- else
- retval = td->td_retval[0];
- audit_commit(td->td_ar, error, retval);
- td->td_ar = NULL;
- td->td_pflags &= ~TDP_AUDITREC;
- }
- void
- audit_cred_copy(struct ucred *src, struct ucred *dest)
- {
- bcopy(&src->cr_audit, &dest->cr_audit, sizeof(dest->cr_audit));
- }
- void
- audit_cred_destroy(struct ucred *cred)
- {
- }
- void
- audit_cred_init(struct ucred *cred)
- {
- bzero(&cred->cr_audit, sizeof(cred->cr_audit));
- }
- /*
- * Initialize audit information for the first kernel process (proc 0) and for
- * the first user process (init).
- */
- void
- audit_cred_kproc0(struct ucred *cred)
- {
- cred->cr_audit.ai_auid = AU_DEFAUDITID;
- cred->cr_audit.ai_termid.at_type = AU_IPv4;
- }
- void
- audit_cred_proc1(struct ucred *cred)
- {
- cred->cr_audit.ai_auid = AU_DEFAUDITID;
- cred->cr_audit.ai_termid.at_type = AU_IPv4;
- }
- void
- audit_thread_alloc(struct thread *td)
- {
- td->td_ar = NULL;
- }
- void
- audit_thread_free(struct thread *td)
- {
- KASSERT(td->td_ar == NULL, ("audit_thread_free: td_ar != NULL"));
- KASSERT((td->td_pflags & TDP_AUDITREC) == 0,
- ("audit_thread_free: TDP_AUDITREC set"));
- }
- void
- audit_proc_coredump(struct thread *td, char *path, int errcode)
- {
- struct kaudit_record *ar;
- struct au_mask *aumask;
- struct ucred *cred;
- au_class_t class;
- int ret, sorf;
- char **pathp;
- au_id_t auid;
- ret = 0;
- /*
- * Make sure we are using the correct preselection mask.
- */
- cred = td->td_ucred;
- auid = cred->cr_audit.ai_auid;
- if (auid == AU_DEFAUDITID)
- aumask = &audit_nae_mask;
- else
- aumask = &cred->cr_audit.ai_mask;
- /*
- * It's possible for coredump(9) generation to fail. Make sure that
- * we handle this case correctly for preselection.
- */
- if (errcode != 0)
- sorf = AU_PRS_FAILURE;
- else
- sorf = AU_PRS_SUCCESS;
- class = au_event_class(AUE_CORE);
- if (au_preselect(AUE_CORE, class, aumask, sorf) == 0 &&
- audit_pipe_preselect(auid, AUE_CORE, class, sorf, 0) == 0)
- return;
- /*
- * If we are interested in seeing this audit record, allocate it.
- * Where possible coredump records should contain a pathname and arg32
- * (signal) tokens.
- */
- ar = audit_new(AUE_CORE, td);
- if (ar == NULL)
- return;
- if (path != NULL) {
- pathp = &ar->k_ar.ar_arg_upath1;
- *pathp = malloc(MAXPATHLEN, M_AUDITPATH, M_WAITOK);
- audit_canon_path(td, AT_FDCWD, path, *pathp);
- ARG_SET_VALID(ar, ARG_UPATH1);
- }
- ar->k_ar.ar_arg_signum = td->td_proc->p_sig;
- ARG_SET_VALID(ar, ARG_SIGNUM);
- if (errcode != 0)
- ret = 1;
- audit_commit(ar, errcode, ret);
- }
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