574adb65c8
Note that some of annotated variables should probably change their types to something smaller, preferably bit-sized.
810 lines
22 KiB
C
810 lines
22 KiB
C
/*-
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* Copyright (c) 1999-2005 Apple Inc.
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* Copyright (c) 2006-2007, 2016-2017 Robert N. M. Watson
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* All rights reserved.
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*
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* Portions of this software were developed by BAE Systems, the University of
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* Cambridge Computer Laboratory, and Memorial University under DARPA/AFRL
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* contract FA8650-15-C-7558 ("CADETS"), as part of the DARPA Transparent
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* Computing (TC) research program.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of Apple Inc. ("Apple") nor the names of
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* its contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR
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* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/condvar.h>
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#include <sys/conf.h>
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#include <sys/file.h>
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#include <sys/filedesc.h>
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#include <sys/fcntl.h>
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#include <sys/ipc.h>
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#include <sys/jail.h>
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#include <sys/kernel.h>
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#include <sys/kthread.h>
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#include <sys/malloc.h>
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#include <sys/mount.h>
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#include <sys/namei.h>
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#include <sys/priv.h>
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#include <sys/proc.h>
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#include <sys/queue.h>
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#include <sys/socket.h>
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#include <sys/socketvar.h>
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#include <sys/protosw.h>
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#include <sys/domain.h>
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#include <sys/sysctl.h>
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#include <sys/sysproto.h>
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#include <sys/sysent.h>
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#include <sys/systm.h>
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#include <sys/ucred.h>
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#include <sys/uio.h>
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#include <sys/un.h>
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#include <sys/unistd.h>
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#include <sys/vnode.h>
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#include <bsm/audit.h>
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#include <bsm/audit_internal.h>
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#include <bsm/audit_kevents.h>
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#include <netinet/in.h>
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#include <netinet/in_pcb.h>
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#include <security/audit/audit.h>
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#include <security/audit/audit_private.h>
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#include <vm/uma.h>
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FEATURE(audit, "BSM audit support");
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static uma_zone_t audit_record_zone;
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static MALLOC_DEFINE(M_AUDITCRED, "audit_cred", "Audit cred storage");
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MALLOC_DEFINE(M_AUDITDATA, "audit_data", "Audit data storage");
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MALLOC_DEFINE(M_AUDITPATH, "audit_path", "Audit path storage");
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MALLOC_DEFINE(M_AUDITTEXT, "audit_text", "Audit text storage");
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MALLOC_DEFINE(M_AUDITGIDSET, "audit_gidset", "Audit GID set storage");
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static SYSCTL_NODE(_security, OID_AUTO, audit, CTLFLAG_RW, 0,
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"TrustedBSD audit controls");
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/*
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* Audit control settings that are set/read by system calls and are hence
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* non-static.
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*
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* Define the audit control flags.
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*/
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int __read_frequently audit_enabled;
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int audit_suspended;
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/*
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* Flags controlling behavior in low storage situations. Should we panic if
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* a write fails? Should we fail stop if we're out of disk space?
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*/
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int audit_panic_on_write_fail;
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int audit_fail_stop;
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int audit_argv;
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int audit_arge;
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/*
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* Are we currently "failing stop" due to out of disk space?
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*/
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int audit_in_failure;
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/*
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* Global audit statistics.
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*/
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struct audit_fstat audit_fstat;
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/*
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* Preselection mask for non-attributable events.
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*/
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struct au_mask audit_nae_mask;
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/*
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* Mutex to protect global variables shared between various threads and
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* processes.
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*/
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struct mtx audit_mtx;
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/*
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* Queue of audit records ready for delivery to disk. We insert new records
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* at the tail, and remove records from the head. Also, a count of the
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* number of records used for checking queue depth. In addition, a counter
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* of records that we have allocated but are not yet in the queue, which is
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* needed to estimate the total size of the combined set of records
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* outstanding in the system.
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*/
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struct kaudit_queue audit_q;
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int audit_q_len;
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int audit_pre_q_len;
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/*
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* Audit queue control settings (minimum free, low/high water marks, etc.)
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*/
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struct au_qctrl audit_qctrl;
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/*
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* Condition variable to signal to the worker that it has work to do: either
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* new records are in the queue, or a log replacement is taking place.
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*/
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struct cv audit_worker_cv;
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/*
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* Condition variable to flag when crossing the low watermark, meaning that
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* threads blocked due to hitting the high watermark can wake up and continue
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* to commit records.
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*/
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struct cv audit_watermark_cv;
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/*
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* Condition variable for auditing threads wait on when in fail-stop mode.
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* Threads wait on this CV forever (and ever), never seeing the light of day
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* again.
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*/
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static struct cv audit_fail_cv;
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/*
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* Optional DTrace audit provider support: function pointers for preselection
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* and commit events.
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*/
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#ifdef KDTRACE_HOOKS
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void *(*dtaudit_hook_preselect)(au_id_t auid, au_event_t event,
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au_class_t class);
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int (*dtaudit_hook_commit)(struct kaudit_record *kar, au_id_t auid,
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au_event_t event, au_class_t class, int sorf);
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void (*dtaudit_hook_bsm)(struct kaudit_record *kar, au_id_t auid,
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au_event_t event, au_class_t class, int sorf,
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void *bsm_data, size_t bsm_lenlen);
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#endif
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/*
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* Kernel audit information. This will store the current audit address
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* or host information that the kernel will use when it's generating
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* audit records. This data is modified by the A_GET{SET}KAUDIT auditon(2)
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* command.
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*/
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static struct auditinfo_addr audit_kinfo;
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static struct rwlock audit_kinfo_lock;
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#define KINFO_LOCK_INIT() rw_init(&audit_kinfo_lock, \
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"audit_kinfo_lock")
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#define KINFO_RLOCK() rw_rlock(&audit_kinfo_lock)
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#define KINFO_WLOCK() rw_wlock(&audit_kinfo_lock)
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#define KINFO_RUNLOCK() rw_runlock(&audit_kinfo_lock)
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#define KINFO_WUNLOCK() rw_wunlock(&audit_kinfo_lock)
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void
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audit_set_kinfo(struct auditinfo_addr *ak)
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{
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KASSERT(ak->ai_termid.at_type == AU_IPv4 ||
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ak->ai_termid.at_type == AU_IPv6,
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("audit_set_kinfo: invalid address type"));
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KINFO_WLOCK();
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audit_kinfo = *ak;
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KINFO_WUNLOCK();
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}
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void
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audit_get_kinfo(struct auditinfo_addr *ak)
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{
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KASSERT(audit_kinfo.ai_termid.at_type == AU_IPv4 ||
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audit_kinfo.ai_termid.at_type == AU_IPv6,
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("audit_set_kinfo: invalid address type"));
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KINFO_RLOCK();
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*ak = audit_kinfo;
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KINFO_RUNLOCK();
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}
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/*
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* Construct an audit record for the passed thread.
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*/
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static int
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audit_record_ctor(void *mem, int size, void *arg, int flags)
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{
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struct kaudit_record *ar;
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struct thread *td;
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struct ucred *cred;
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struct prison *pr;
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KASSERT(sizeof(*ar) == size, ("audit_record_ctor: wrong size"));
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td = arg;
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ar = mem;
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bzero(ar, sizeof(*ar));
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ar->k_ar.ar_magic = AUDIT_RECORD_MAGIC;
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nanotime(&ar->k_ar.ar_starttime);
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/*
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* Export the subject credential.
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*/
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cred = td->td_ucred;
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cru2x(cred, &ar->k_ar.ar_subj_cred);
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ar->k_ar.ar_subj_ruid = cred->cr_ruid;
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ar->k_ar.ar_subj_rgid = cred->cr_rgid;
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ar->k_ar.ar_subj_egid = cred->cr_groups[0];
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ar->k_ar.ar_subj_auid = cred->cr_audit.ai_auid;
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ar->k_ar.ar_subj_asid = cred->cr_audit.ai_asid;
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ar->k_ar.ar_subj_pid = td->td_proc->p_pid;
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ar->k_ar.ar_subj_amask = cred->cr_audit.ai_mask;
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ar->k_ar.ar_subj_term_addr = cred->cr_audit.ai_termid;
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/*
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* If this process is jailed, make sure we capture the name of the
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* jail so we can use it to generate a zonename token when we covert
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* this record to BSM.
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*/
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if (jailed(cred)) {
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pr = cred->cr_prison;
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(void) strlcpy(ar->k_ar.ar_jailname, pr->pr_name,
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sizeof(ar->k_ar.ar_jailname));
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} else
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ar->k_ar.ar_jailname[0] = '\0';
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return (0);
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}
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static void
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audit_record_dtor(void *mem, int size, void *arg)
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{
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struct kaudit_record *ar;
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KASSERT(sizeof(*ar) == size, ("audit_record_dtor: wrong size"));
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ar = mem;
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if (ar->k_ar.ar_arg_upath1 != NULL)
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free(ar->k_ar.ar_arg_upath1, M_AUDITPATH);
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if (ar->k_ar.ar_arg_upath2 != NULL)
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free(ar->k_ar.ar_arg_upath2, M_AUDITPATH);
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if (ar->k_ar.ar_arg_text != NULL)
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free(ar->k_ar.ar_arg_text, M_AUDITTEXT);
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if (ar->k_udata != NULL)
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free(ar->k_udata, M_AUDITDATA);
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if (ar->k_ar.ar_arg_argv != NULL)
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free(ar->k_ar.ar_arg_argv, M_AUDITTEXT);
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if (ar->k_ar.ar_arg_envv != NULL)
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free(ar->k_ar.ar_arg_envv, M_AUDITTEXT);
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if (ar->k_ar.ar_arg_groups.gidset != NULL)
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free(ar->k_ar.ar_arg_groups.gidset, M_AUDITGIDSET);
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}
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/*
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* Initialize the Audit subsystem: configuration state, work queue,
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* synchronization primitives, worker thread, and trigger device node. Also
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* call into the BSM assembly code to initialize it.
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*/
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static void
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audit_init(void)
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{
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audit_enabled = 0;
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audit_suspended = 0;
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audit_panic_on_write_fail = 0;
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audit_fail_stop = 0;
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audit_in_failure = 0;
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audit_argv = 0;
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audit_arge = 0;
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audit_fstat.af_filesz = 0; /* '0' means unset, unbounded. */
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audit_fstat.af_currsz = 0;
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audit_nae_mask.am_success = 0;
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audit_nae_mask.am_failure = 0;
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TAILQ_INIT(&audit_q);
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audit_q_len = 0;
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audit_pre_q_len = 0;
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audit_qctrl.aq_hiwater = AQ_HIWATER;
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audit_qctrl.aq_lowater = AQ_LOWATER;
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audit_qctrl.aq_bufsz = AQ_BUFSZ;
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audit_qctrl.aq_minfree = AU_FS_MINFREE;
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audit_kinfo.ai_termid.at_type = AU_IPv4;
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audit_kinfo.ai_termid.at_addr[0] = INADDR_ANY;
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mtx_init(&audit_mtx, "audit_mtx", NULL, MTX_DEF);
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KINFO_LOCK_INIT();
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cv_init(&audit_worker_cv, "audit_worker_cv");
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cv_init(&audit_watermark_cv, "audit_watermark_cv");
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cv_init(&audit_fail_cv, "audit_fail_cv");
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audit_record_zone = uma_zcreate("audit_record",
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sizeof(struct kaudit_record), audit_record_ctor,
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audit_record_dtor, NULL, NULL, UMA_ALIGN_PTR, 0);
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/* Initialize the BSM audit subsystem. */
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kau_init();
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audit_trigger_init();
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/* Register shutdown handler. */
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EVENTHANDLER_REGISTER(shutdown_pre_sync, audit_shutdown, NULL,
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SHUTDOWN_PRI_FIRST);
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/* Start audit worker thread. */
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audit_worker_init();
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}
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SYSINIT(audit_init, SI_SUB_AUDIT, SI_ORDER_FIRST, audit_init, NULL);
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/*
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* Drain the audit queue and close the log at shutdown. Note that this can
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* be called both from the system shutdown path and also from audit
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* configuration syscalls, so 'arg' and 'howto' are ignored.
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*
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* XXXRW: In FreeBSD 7.x and 8.x, this fails to wait for the record queue to
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* drain before returning, which could lead to lost records on shutdown.
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*/
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void
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audit_shutdown(void *arg, int howto)
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{
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audit_rotate_vnode(NULL, NULL);
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}
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/*
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* Return the current thread's audit record, if any.
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*/
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struct kaudit_record *
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currecord(void)
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{
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return (curthread->td_ar);
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}
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/*
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* XXXAUDIT: There are a number of races present in the code below due to
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* release and re-grab of the mutex. The code should be revised to become
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* slightly less racy.
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*
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* XXXAUDIT: Shouldn't there be logic here to sleep waiting on available
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* pre_q space, suspending the system call until there is room?
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*/
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struct kaudit_record *
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audit_new(int event, struct thread *td)
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{
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struct kaudit_record *ar;
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int no_record;
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mtx_lock(&audit_mtx);
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no_record = (audit_suspended || !audit_enabled);
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mtx_unlock(&audit_mtx);
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if (no_record)
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return (NULL);
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/*
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* Note: the number of outstanding uncommitted audit records is
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* limited to the number of concurrent threads servicing system calls
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* in the kernel.
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*/
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ar = uma_zalloc_arg(audit_record_zone, td, M_WAITOK);
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ar->k_ar.ar_event = event;
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mtx_lock(&audit_mtx);
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audit_pre_q_len++;
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mtx_unlock(&audit_mtx);
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return (ar);
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}
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void
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audit_free(struct kaudit_record *ar)
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{
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uma_zfree(audit_record_zone, ar);
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}
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void
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audit_commit(struct kaudit_record *ar, int error, int retval)
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{
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au_event_t event;
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au_class_t class;
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au_id_t auid;
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int sorf;
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struct au_mask *aumask;
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if (ar == NULL)
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return;
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ar->k_ar.ar_errno = error;
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ar->k_ar.ar_retval = retval;
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nanotime(&ar->k_ar.ar_endtime);
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/*
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* Decide whether to commit the audit record by checking the error
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* value from the system call and using the appropriate audit mask.
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*/
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if (ar->k_ar.ar_subj_auid == AU_DEFAUDITID)
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aumask = &audit_nae_mask;
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else
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aumask = &ar->k_ar.ar_subj_amask;
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if (error)
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sorf = AU_PRS_FAILURE;
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else
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sorf = AU_PRS_SUCCESS;
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/*
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* syscalls.master sometimes contains a prototype event number, which
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* we will transform into a more specific event number now that we
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* have more complete information gathered during the system call.
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*/
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switch(ar->k_ar.ar_event) {
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case AUE_OPEN_RWTC:
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ar->k_ar.ar_event = audit_flags_and_error_to_openevent(
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ar->k_ar.ar_arg_fflags, error);
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break;
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case AUE_OPENAT_RWTC:
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ar->k_ar.ar_event = audit_flags_and_error_to_openatevent(
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ar->k_ar.ar_arg_fflags, error);
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break;
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case AUE_SYSCTL:
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ar->k_ar.ar_event = audit_ctlname_to_sysctlevent(
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ar->k_ar.ar_arg_ctlname, ar->k_ar.ar_valid_arg);
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break;
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case AUE_AUDITON:
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/* Convert the auditon() command to an event. */
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ar->k_ar.ar_event = auditon_command_event(ar->k_ar.ar_arg_cmd);
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break;
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case AUE_MSGSYS:
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if (ARG_IS_VALID(ar, ARG_SVIPC_WHICH))
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ar->k_ar.ar_event =
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audit_msgsys_to_event(ar->k_ar.ar_arg_svipc_which);
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break;
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case AUE_SEMSYS:
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if (ARG_IS_VALID(ar, ARG_SVIPC_WHICH))
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|
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?
|
|
*/
|
|
mtx_lock(&audit_mtx);
|
|
if (audit_suspended || !audit_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.
|
|
*/
|
|
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);
|
|
}
|