audit.c revision 181604
1181053Srwatson/*- 2180701Srwatson * Copyright (c) 1999-2005 Apple Inc. 3170407Srwatson * Copyright (c) 2006-2007 Robert N. M. Watson 4155192Srwatson * All rights reserved. 5155192Srwatson * 6155192Srwatson * Redistribution and use in source and binary forms, with or without 7155192Srwatson * modification, are permitted provided that the following conditions 8155192Srwatson * are met: 9155192Srwatson * 1. Redistributions of source code must retain the above copyright 10155192Srwatson * notice, this list of conditions and the following disclaimer. 11155192Srwatson * 2. Redistributions in binary form must reproduce the above copyright 12155192Srwatson * notice, this list of conditions and the following disclaimer in the 13155192Srwatson * documentation and/or other materials provided with the distribution. 14180701Srwatson * 3. Neither the name of Apple Inc. ("Apple") nor the names of 15155192Srwatson * its contributors may be used to endorse or promote products derived 16155192Srwatson * from this software without specific prior written permission. 17155192Srwatson * 18155192Srwatson * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND 19155192Srwatson * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20155192Srwatson * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21155192Srwatson * ARE DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR 22155192Srwatson * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23155192Srwatson * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24155192Srwatson * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25155192Srwatson * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 26155192Srwatson * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 27155192Srwatson * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28155192Srwatson * POSSIBILITY OF SUCH DAMAGE. 29155192Srwatson */ 30155192Srwatson 31178186Srwatson#include <sys/cdefs.h> 32178186Srwatson__FBSDID("$FreeBSD: head/sys/security/audit/audit.c 181604 2008-08-11 20:14:56Z csjp $"); 33178186Srwatson 34155192Srwatson#include <sys/param.h> 35155192Srwatson#include <sys/condvar.h> 36155192Srwatson#include <sys/conf.h> 37155192Srwatson#include <sys/file.h> 38155192Srwatson#include <sys/filedesc.h> 39155192Srwatson#include <sys/fcntl.h> 40155192Srwatson#include <sys/ipc.h> 41155192Srwatson#include <sys/kernel.h> 42155192Srwatson#include <sys/kthread.h> 43155192Srwatson#include <sys/malloc.h> 44155192Srwatson#include <sys/mount.h> 45155192Srwatson#include <sys/namei.h> 46164033Srwatson#include <sys/priv.h> 47155192Srwatson#include <sys/proc.h> 48155192Srwatson#include <sys/queue.h> 49155192Srwatson#include <sys/socket.h> 50155192Srwatson#include <sys/socketvar.h> 51155192Srwatson#include <sys/protosw.h> 52155192Srwatson#include <sys/domain.h> 53171144Srwatson#include <sys/sysctl.h> 54155192Srwatson#include <sys/sysproto.h> 55155192Srwatson#include <sys/sysent.h> 56155192Srwatson#include <sys/systm.h> 57155192Srwatson#include <sys/ucred.h> 58155192Srwatson#include <sys/uio.h> 59155192Srwatson#include <sys/un.h> 60155192Srwatson#include <sys/unistd.h> 61155192Srwatson#include <sys/vnode.h> 62155192Srwatson 63155406Srwatson#include <bsm/audit.h> 64156291Srwatson#include <bsm/audit_internal.h> 65155406Srwatson#include <bsm/audit_kevents.h> 66155406Srwatson 67155192Srwatson#include <netinet/in.h> 68155192Srwatson#include <netinet/in_pcb.h> 69155192Srwatson 70155192Srwatson#include <security/audit/audit.h> 71155192Srwatson#include <security/audit/audit_private.h> 72155192Srwatson 73155406Srwatson#include <vm/uma.h> 74155406Srwatson 75156888Srwatsonstatic uma_zone_t audit_record_zone; 76170407Srwatsonstatic MALLOC_DEFINE(M_AUDITCRED, "audit_cred", "Audit cred storage"); 77155192SrwatsonMALLOC_DEFINE(M_AUDITDATA, "audit_data", "Audit data storage"); 78155192SrwatsonMALLOC_DEFINE(M_AUDITPATH, "audit_path", "Audit path storage"); 79155192SrwatsonMALLOC_DEFINE(M_AUDITTEXT, "audit_text", "Audit text storage"); 80155192Srwatson 81171144SrwatsonSYSCTL_NODE(_security, OID_AUTO, audit, CTLFLAG_RW, 0, 82171144Srwatson "TrustedBSD audit controls"); 83171144Srwatson 84155192Srwatson/* 85170196Srwatson * Audit control settings that are set/read by system calls and are hence 86170196Srwatson * non-static. 87170196Srwatson * 88155192Srwatson * Define the audit control flags. 89155192Srwatson */ 90156889Srwatsonint audit_enabled; 91156889Srwatsonint audit_suspended; 92155192Srwatson 93155192Srwatson/* 94162176Srwatson * Flags controlling behavior in low storage situations. Should we panic if 95162176Srwatson * a write fails? Should we fail stop if we're out of disk space? 96155192Srwatson */ 97156889Srwatsonint audit_panic_on_write_fail; 98156889Srwatsonint audit_fail_stop; 99161813Swsalamonint audit_argv; 100161813Swsalamonint audit_arge; 101155192Srwatson 102155192Srwatson/* 103155192Srwatson * Are we currently "failing stop" due to out of disk space? 104155192Srwatson */ 105156889Srwatsonint audit_in_failure; 106155192Srwatson 107155192Srwatson/* 108170691Srwatson * Global audit statistics. 109155192Srwatson */ 110156889Srwatsonstruct audit_fstat audit_fstat; 111155192Srwatson 112155192Srwatson/* 113155192Srwatson * Preselection mask for non-attributable events. 114155192Srwatson */ 115156889Srwatsonstruct au_mask audit_nae_mask; 116155192Srwatson 117155192Srwatson/* 118155192Srwatson * Mutex to protect global variables shared between various threads and 119155192Srwatson * processes. 120155192Srwatson */ 121156889Srwatsonstruct mtx audit_mtx; 122155192Srwatson 123155192Srwatson/* 124170196Srwatson * Queue of audit records ready for delivery to disk. We insert new records 125170196Srwatson * at the tail, and remove records from the head. Also, a count of the 126170196Srwatson * number of records used for checking queue depth. In addition, a counter 127170196Srwatson * of records that we have allocated but are not yet in the queue, which is 128170196Srwatson * needed to estimate the total size of the combined set of records 129170196Srwatson * outstanding in the system. 130155192Srwatson */ 131156889Srwatsonstruct kaudit_queue audit_q; 132156889Srwatsonint audit_q_len; 133156889Srwatsonint audit_pre_q_len; 134155192Srwatson 135155192Srwatson/* 136155192Srwatson * Audit queue control settings (minimum free, low/high water marks, etc.) 137155192Srwatson */ 138156889Srwatsonstruct au_qctrl audit_qctrl; 139155192Srwatson 140155192Srwatson/* 141170196Srwatson * Condition variable to signal to the worker that it has work to do: either 142170196Srwatson * new records are in the queue, or a log replacement is taking place. 143155192Srwatson */ 144159261Srwatsonstruct cv audit_worker_cv; 145155192Srwatson 146155192Srwatson/* 147159261Srwatson * Condition variable to flag when crossing the low watermark, meaning that 148159261Srwatson * threads blocked due to hitting the high watermark can wake up and continue 149159261Srwatson * to commit records. 150155192Srwatson */ 151159261Srwatsonstruct cv audit_watermark_cv; 152155192Srwatson 153156889Srwatson/* 154156889Srwatson * Condition variable for auditing threads wait on when in fail-stop mode. 155170196Srwatson * Threads wait on this CV forever (and ever), never seeing the light of day 156170196Srwatson * again. 157155192Srwatson */ 158156889Srwatsonstatic struct cv audit_fail_cv; 159155192Srwatson 160155192Srwatson/* 161155406Srwatson * Construct an audit record for the passed thread. 162155192Srwatson */ 163155406Srwatsonstatic int 164155406Srwatsonaudit_record_ctor(void *mem, int size, void *arg, int flags) 165155406Srwatson{ 166155406Srwatson struct kaudit_record *ar; 167155406Srwatson struct thread *td; 168155406Srwatson 169155406Srwatson KASSERT(sizeof(*ar) == size, ("audit_record_ctor: wrong size")); 170155406Srwatson 171155406Srwatson td = arg; 172155406Srwatson ar = mem; 173155406Srwatson bzero(ar, sizeof(*ar)); 174155406Srwatson ar->k_ar.ar_magic = AUDIT_RECORD_MAGIC; 175155406Srwatson nanotime(&ar->k_ar.ar_starttime); 176155406Srwatson 177155406Srwatson /* 178155406Srwatson * Export the subject credential. 179155406Srwatson */ 180155406Srwatson cru2x(td->td_ucred, &ar->k_ar.ar_subj_cred); 181155406Srwatson ar->k_ar.ar_subj_ruid = td->td_ucred->cr_ruid; 182155406Srwatson ar->k_ar.ar_subj_rgid = td->td_ucred->cr_rgid; 183155406Srwatson ar->k_ar.ar_subj_egid = td->td_ucred->cr_groups[0]; 184170407Srwatson ar->k_ar.ar_subj_auid = td->td_ucred->cr_audit.ai_auid; 185170407Srwatson ar->k_ar.ar_subj_asid = td->td_ucred->cr_audit.ai_asid; 186155406Srwatson ar->k_ar.ar_subj_pid = td->td_proc->p_pid; 187170407Srwatson ar->k_ar.ar_subj_amask = td->td_ucred->cr_audit.ai_mask; 188170407Srwatson ar->k_ar.ar_subj_term_addr = td->td_ucred->cr_audit.ai_termid; 189155406Srwatson return (0); 190155406Srwatson} 191155406Srwatson 192155192Srwatsonstatic void 193155406Srwatsonaudit_record_dtor(void *mem, int size, void *arg) 194155192Srwatson{ 195155406Srwatson struct kaudit_record *ar; 196155192Srwatson 197155406Srwatson KASSERT(sizeof(*ar) == size, ("audit_record_dtor: wrong size")); 198155406Srwatson 199155406Srwatson ar = mem; 200155406Srwatson if (ar->k_ar.ar_arg_upath1 != NULL) 201155192Srwatson free(ar->k_ar.ar_arg_upath1, M_AUDITPATH); 202155406Srwatson if (ar->k_ar.ar_arg_upath2 != NULL) 203155192Srwatson free(ar->k_ar.ar_arg_upath2, M_AUDITPATH); 204155406Srwatson if (ar->k_ar.ar_arg_text != NULL) 205155192Srwatson free(ar->k_ar.ar_arg_text, M_AUDITTEXT); 206155406Srwatson if (ar->k_udata != NULL) 207155192Srwatson free(ar->k_udata, M_AUDITDATA); 208161813Swsalamon if (ar->k_ar.ar_arg_argv != NULL) 209161813Swsalamon free(ar->k_ar.ar_arg_argv, M_AUDITTEXT); 210161813Swsalamon if (ar->k_ar.ar_arg_envv != NULL) 211161813Swsalamon free(ar->k_ar.ar_arg_envv, M_AUDITTEXT); 212155192Srwatson} 213155192Srwatson 214155192Srwatson/* 215155192Srwatson * Initialize the Audit subsystem: configuration state, work queue, 216155192Srwatson * synchronization primitives, worker thread, and trigger device node. Also 217155192Srwatson * call into the BSM assembly code to initialize it. 218155192Srwatson */ 219155192Srwatsonstatic void 220155192Srwatsonaudit_init(void) 221155192Srwatson{ 222155192Srwatson 223155192Srwatson audit_enabled = 0; 224155192Srwatson audit_suspended = 0; 225155192Srwatson audit_panic_on_write_fail = 0; 226155192Srwatson audit_fail_stop = 0; 227155192Srwatson audit_in_failure = 0; 228161813Swsalamon audit_argv = 0; 229161813Swsalamon audit_arge = 0; 230155192Srwatson 231170196Srwatson audit_fstat.af_filesz = 0; /* '0' means unset, unbounded. */ 232156889Srwatson audit_fstat.af_currsz = 0; 233173142Srwatson audit_nae_mask.am_success = 0; 234173142Srwatson audit_nae_mask.am_failure = 0; 235155192Srwatson 236155192Srwatson TAILQ_INIT(&audit_q); 237155192Srwatson audit_q_len = 0; 238155192Srwatson audit_pre_q_len = 0; 239155192Srwatson audit_qctrl.aq_hiwater = AQ_HIWATER; 240155192Srwatson audit_qctrl.aq_lowater = AQ_LOWATER; 241155192Srwatson audit_qctrl.aq_bufsz = AQ_BUFSZ; 242155192Srwatson audit_qctrl.aq_minfree = AU_FS_MINFREE; 243155192Srwatson 244155192Srwatson mtx_init(&audit_mtx, "audit_mtx", NULL, MTX_DEF); 245159261Srwatson cv_init(&audit_worker_cv, "audit_worker_cv"); 246159261Srwatson cv_init(&audit_watermark_cv, "audit_watermark_cv"); 247155192Srwatson cv_init(&audit_fail_cv, "audit_fail_cv"); 248155192Srwatson 249159266Srwatson audit_record_zone = uma_zcreate("audit_record", 250155406Srwatson sizeof(struct kaudit_record), audit_record_ctor, 251155406Srwatson audit_record_dtor, NULL, NULL, UMA_ALIGN_PTR, 0); 252155406Srwatson 253155192Srwatson /* Initialize the BSM audit subsystem. */ 254155192Srwatson kau_init(); 255155192Srwatson 256155192Srwatson audit_trigger_init(); 257155192Srwatson 258155192Srwatson /* Register shutdown handler. */ 259155192Srwatson EVENTHANDLER_REGISTER(shutdown_pre_sync, audit_shutdown, NULL, 260155192Srwatson SHUTDOWN_PRI_FIRST); 261155192Srwatson 262156888Srwatson /* Start audit worker thread. */ 263156888Srwatson audit_worker_init(); 264155192Srwatson} 265155192Srwatson 266177253SrwatsonSYSINIT(audit_init, SI_SUB_AUDIT, SI_ORDER_FIRST, audit_init, NULL); 267155192Srwatson 268155192Srwatson/* 269155192Srwatson * Drain the audit queue and close the log at shutdown. Note that this can 270155192Srwatson * be called both from the system shutdown path and also from audit 271155192Srwatson * configuration syscalls, so 'arg' and 'howto' are ignored. 272179517Srwatson * 273179517Srwatson * XXXRW: In FreeBSD 7.x and 8.x, this fails to wait for the record queue to 274179517Srwatson * drain before returning, which could lead to lost records on shutdown. 275155192Srwatson */ 276155192Srwatsonvoid 277155192Srwatsonaudit_shutdown(void *arg, int howto) 278155192Srwatson{ 279155192Srwatson 280155192Srwatson audit_rotate_vnode(NULL, NULL); 281155192Srwatson} 282155192Srwatson 283155192Srwatson/* 284155192Srwatson * Return the current thread's audit record, if any. 285155192Srwatson */ 286169896Srwatsonstruct kaudit_record * 287155192Srwatsoncurrecord(void) 288155192Srwatson{ 289155192Srwatson 290155192Srwatson return (curthread->td_ar); 291155192Srwatson} 292155192Srwatson 293155192Srwatson/* 294155192Srwatson * XXXAUDIT: There are a number of races present in the code below due to 295155192Srwatson * release and re-grab of the mutex. The code should be revised to become 296155192Srwatson * slightly less racy. 297155192Srwatson * 298155192Srwatson * XXXAUDIT: Shouldn't there be logic here to sleep waiting on available 299155192Srwatson * pre_q space, suspending the system call until there is room? 300155192Srwatson */ 301155192Srwatsonstruct kaudit_record * 302155192Srwatsonaudit_new(int event, struct thread *td) 303155192Srwatson{ 304155192Srwatson struct kaudit_record *ar; 305155192Srwatson int no_record; 306155192Srwatson 307155406Srwatson mtx_lock(&audit_mtx); 308155406Srwatson no_record = (audit_suspended || !audit_enabled); 309155406Srwatson mtx_unlock(&audit_mtx); 310155406Srwatson if (no_record) 311155406Srwatson return (NULL); 312155192Srwatson 313155192Srwatson /* 314165604Srwatson * Note: the number of outstanding uncommitted audit records is 315165604Srwatson * limited to the number of concurrent threads servicing system calls 316165604Srwatson * in the kernel. 317155192Srwatson */ 318155406Srwatson ar = uma_zalloc_arg(audit_record_zone, td, M_WAITOK); 319155406Srwatson ar->k_ar.ar_event = event; 320155192Srwatson 321155192Srwatson mtx_lock(&audit_mtx); 322155192Srwatson audit_pre_q_len++; 323155192Srwatson mtx_unlock(&audit_mtx); 324155192Srwatson 325155192Srwatson return (ar); 326155192Srwatson} 327155192Srwatson 328156888Srwatsonvoid 329156888Srwatsonaudit_free(struct kaudit_record *ar) 330156888Srwatson{ 331156888Srwatson 332156888Srwatson uma_zfree(audit_record_zone, ar); 333156888Srwatson} 334156888Srwatson 335155192Srwatsonvoid 336155192Srwatsonaudit_commit(struct kaudit_record *ar, int error, int retval) 337155192Srwatson{ 338159269Srwatson au_event_t event; 339159269Srwatson au_class_t class; 340159269Srwatson au_id_t auid; 341155192Srwatson int sorf; 342155192Srwatson struct au_mask *aumask; 343155192Srwatson 344155192Srwatson if (ar == NULL) 345155192Srwatson return; 346155192Srwatson 347155192Srwatson /* 348170196Srwatson * Decide whether to commit the audit record by checking the error 349170196Srwatson * value from the system call and using the appropriate audit mask. 350155192Srwatson */ 351155192Srwatson if (ar->k_ar.ar_subj_auid == AU_DEFAUDITID) 352155192Srwatson aumask = &audit_nae_mask; 353155192Srwatson else 354155192Srwatson aumask = &ar->k_ar.ar_subj_amask; 355156889Srwatson 356155192Srwatson if (error) 357155192Srwatson sorf = AU_PRS_FAILURE; 358155192Srwatson else 359155192Srwatson sorf = AU_PRS_SUCCESS; 360155192Srwatson 361155192Srwatson switch(ar->k_ar.ar_event) { 362155192Srwatson case AUE_OPEN_RWTC: 363170196Srwatson /* 364170196Srwatson * The open syscall always writes a AUE_OPEN_RWTC event; 365170196Srwatson * change it to the proper type of event based on the flags 366170196Srwatson * and the error value. 367155192Srwatson */ 368176690Srwatson ar->k_ar.ar_event = audit_flags_and_error_to_openevent( 369155192Srwatson ar->k_ar.ar_arg_fflags, error); 370155192Srwatson break; 371155192Srwatson 372155192Srwatson case AUE_SYSCTL: 373176690Srwatson ar->k_ar.ar_event = audit_ctlname_to_sysctlevent( 374155192Srwatson ar->k_ar.ar_arg_ctlname, ar->k_ar.ar_valid_arg); 375155192Srwatson break; 376155192Srwatson 377155192Srwatson case AUE_AUDITON: 378170585Srwatson /* Convert the auditon() command to an event. */ 379155192Srwatson ar->k_ar.ar_event = auditon_command_event(ar->k_ar.ar_arg_cmd); 380155192Srwatson break; 381155192Srwatson } 382155192Srwatson 383159269Srwatson auid = ar->k_ar.ar_subj_auid; 384159269Srwatson event = ar->k_ar.ar_event; 385159269Srwatson class = au_event_class(event); 386155192Srwatson 387159269Srwatson ar->k_ar_commit |= AR_COMMIT_KERNEL; 388159269Srwatson if (au_preselect(event, class, aumask, sorf) != 0) 389159269Srwatson ar->k_ar_commit |= AR_PRESELECT_TRAIL; 390159269Srwatson if (audit_pipe_preselect(auid, event, class, sorf, 391159269Srwatson ar->k_ar_commit & AR_PRESELECT_TRAIL) != 0) 392159269Srwatson ar->k_ar_commit |= AR_PRESELECT_PIPE; 393162380Scsjp if ((ar->k_ar_commit & (AR_PRESELECT_TRAIL | AR_PRESELECT_PIPE | 394162380Scsjp AR_PRESELECT_USER_TRAIL | AR_PRESELECT_USER_PIPE)) == 0) { 395155192Srwatson mtx_lock(&audit_mtx); 396155192Srwatson audit_pre_q_len--; 397155192Srwatson mtx_unlock(&audit_mtx); 398159275Srwatson audit_free(ar); 399155192Srwatson return; 400155192Srwatson } 401155192Srwatson 402155192Srwatson ar->k_ar.ar_errno = error; 403155192Srwatson ar->k_ar.ar_retval = retval; 404155192Srwatson nanotime(&ar->k_ar.ar_endtime); 405155192Srwatson 406155192Srwatson /* 407155192Srwatson * Note: it could be that some records initiated while audit was 408155192Srwatson * enabled should still be committed? 409155192Srwatson */ 410170196Srwatson mtx_lock(&audit_mtx); 411155192Srwatson if (audit_suspended || !audit_enabled) { 412155192Srwatson audit_pre_q_len--; 413155192Srwatson mtx_unlock(&audit_mtx); 414159275Srwatson audit_free(ar); 415155192Srwatson return; 416155192Srwatson } 417156889Srwatson 418155192Srwatson /* 419170182Srwatson * Constrain the number of committed audit records based on the 420170182Srwatson * configurable parameter. 421155192Srwatson */ 422170182Srwatson while (audit_q_len >= audit_qctrl.aq_hiwater) 423159261Srwatson cv_wait(&audit_watermark_cv, &audit_mtx); 424155192Srwatson 425155192Srwatson TAILQ_INSERT_TAIL(&audit_q, ar, k_q); 426155192Srwatson audit_q_len++; 427155192Srwatson audit_pre_q_len--; 428159261Srwatson cv_signal(&audit_worker_cv); 429155192Srwatson mtx_unlock(&audit_mtx); 430155192Srwatson} 431155192Srwatson 432155192Srwatson/* 433155192Srwatson * audit_syscall_enter() is called on entry to each system call. It is 434155192Srwatson * responsible for deciding whether or not to audit the call (preselection), 435155192Srwatson * and if so, allocating a per-thread audit record. audit_new() will fill in 436155192Srwatson * basic thread/credential properties. 437155192Srwatson */ 438155192Srwatsonvoid 439155192Srwatsonaudit_syscall_enter(unsigned short code, struct thread *td) 440155192Srwatson{ 441155192Srwatson struct au_mask *aumask; 442159269Srwatson au_class_t class; 443159269Srwatson au_event_t event; 444159269Srwatson au_id_t auid; 445155192Srwatson 446155192Srwatson KASSERT(td->td_ar == NULL, ("audit_syscall_enter: td->td_ar != NULL")); 447155192Srwatson 448155192Srwatson /* 449155192Srwatson * In FreeBSD, each ABI has its own system call table, and hence 450155192Srwatson * mapping of system call codes to audit events. Convert the code to 451155192Srwatson * an audit event identifier using the process system call table 452155192Srwatson * reference. In Darwin, there's only one, so we use the global 453162950Srwatson * symbol for the system call table. No audit record is generated 454162950Srwatson * for bad system calls, as no operation has been performed. 455155192Srwatson */ 456155192Srwatson if (code >= td->td_proc->p_sysent->sv_size) 457155192Srwatson return; 458155192Srwatson 459159269Srwatson event = td->td_proc->p_sysent->sv_table[code].sy_auevent; 460159269Srwatson if (event == AUE_NULL) 461155192Srwatson return; 462155192Srwatson 463155192Srwatson /* 464155192Srwatson * Check which audit mask to use; either the kernel non-attributable 465155192Srwatson * event mask or the process audit mask. 466155192Srwatson */ 467170407Srwatson auid = td->td_ucred->cr_audit.ai_auid; 468159269Srwatson if (auid == AU_DEFAUDITID) 469155192Srwatson aumask = &audit_nae_mask; 470155192Srwatson else 471170407Srwatson aumask = &td->td_ucred->cr_audit.ai_mask; 472156889Srwatson 473155192Srwatson /* 474170196Srwatson * Allocate an audit record, if preselection allows it, and store in 475170196Srwatson * the thread for later use. 476155192Srwatson */ 477159269Srwatson class = au_event_class(event); 478159269Srwatson if (au_preselect(event, class, aumask, AU_PRS_BOTH)) { 479155192Srwatson /* 480155192Srwatson * If we're out of space and need to suspend unprivileged 481155192Srwatson * processes, do that here rather than trying to allocate 482155192Srwatson * another audit record. 483155192Srwatson * 484165604Srwatson * Note: we might wish to be able to continue here in the 485155192Srwatson * future, if the system recovers. That should be possible 486155192Srwatson * by means of checking the condition in a loop around 487155192Srwatson * cv_wait(). It might be desirable to reevaluate whether an 488155192Srwatson * audit record is still required for this event by 489155192Srwatson * re-calling au_preselect(). 490155192Srwatson */ 491164033Srwatson if (audit_in_failure && 492164033Srwatson priv_check(td, PRIV_AUDIT_FAILSTOP) != 0) { 493155192Srwatson cv_wait(&audit_fail_cv, &audit_mtx); 494155192Srwatson panic("audit_failing_stop: thread continued"); 495155192Srwatson } 496159269Srwatson td->td_ar = audit_new(event, td); 497159269Srwatson } else if (audit_pipe_preselect(auid, event, class, AU_PRS_BOTH, 0)) 498159269Srwatson td->td_ar = audit_new(event, td); 499159269Srwatson else 500155192Srwatson td->td_ar = NULL; 501155192Srwatson} 502155192Srwatson 503155192Srwatson/* 504155192Srwatson * audit_syscall_exit() is called from the return of every system call, or in 505155192Srwatson * the event of exit1(), during the execution of exit1(). It is responsible 506155192Srwatson * for committing the audit record, if any, along with return condition. 507155192Srwatson */ 508155192Srwatsonvoid 509155192Srwatsonaudit_syscall_exit(int error, struct thread *td) 510155192Srwatson{ 511155192Srwatson int retval; 512155192Srwatson 513155192Srwatson /* 514170196Srwatson * Commit the audit record as desired; once we pass the record into 515170196Srwatson * audit_commit(), the memory is owned by the audit subsystem. The 516170196Srwatson * return value from the system call is stored on the user thread. 517170196Srwatson * If there was an error, the return value is set to -1, imitating 518170196Srwatson * the behavior of the cerror routine. 519155192Srwatson */ 520155192Srwatson if (error) 521155192Srwatson retval = -1; 522155192Srwatson else 523155192Srwatson retval = td->td_retval[0]; 524155192Srwatson 525155192Srwatson audit_commit(td->td_ar, error, retval); 526155192Srwatson td->td_ar = NULL; 527155192Srwatson} 528155192Srwatson 529155192Srwatsonvoid 530170407Srwatsonaudit_cred_copy(struct ucred *src, struct ucred *dest) 531155192Srwatson{ 532155192Srwatson 533170407Srwatson bcopy(&src->cr_audit, &dest->cr_audit, sizeof(dest->cr_audit)); 534155192Srwatson} 535155192Srwatson 536155195Srwatsonvoid 537170407Srwatsonaudit_cred_destroy(struct ucred *cred) 538155195Srwatson{ 539155195Srwatson 540155195Srwatson} 541155195Srwatson 542155353Srwatsonvoid 543170407Srwatsonaudit_cred_init(struct ucred *cred) 544155353Srwatson{ 545155353Srwatson 546170407Srwatson bzero(&cred->cr_audit, sizeof(cred->cr_audit)); 547155353Srwatson} 548155353Srwatson 549156889Srwatson/* 550162950Srwatson * Initialize audit information for the first kernel process (proc 0) and for 551162950Srwatson * the first user process (init). 552155192Srwatson */ 553155192Srwatsonvoid 554170407Srwatsonaudit_cred_kproc0(struct ucred *cred) 555155192Srwatson{ 556155192Srwatson 557170585Srwatson cred->cr_audit.ai_auid = AU_DEFAUDITID; 558175763Scsjp cred->cr_audit.ai_termid.at_type = AU_IPv4; 559155192Srwatson} 560155192Srwatson 561155192Srwatsonvoid 562170407Srwatsonaudit_cred_proc1(struct ucred *cred) 563155192Srwatson{ 564155192Srwatson 565170407Srwatson cred->cr_audit.ai_auid = AU_DEFAUDITID; 566175763Scsjp cred->cr_audit.ai_termid.at_type = AU_IPv4; 567155192Srwatson} 568155192Srwatson 569155192Srwatsonvoid 570170407Srwatsonaudit_thread_alloc(struct thread *td) 571155192Srwatson{ 572155192Srwatson 573170407Srwatson td->td_ar = NULL; 574155192Srwatson} 575155192Srwatson 576155192Srwatsonvoid 577170407Srwatsonaudit_thread_free(struct thread *td) 578155192Srwatson{ 579155192Srwatson 580170407Srwatson KASSERT(td->td_ar == NULL, ("audit_thread_free: td_ar != NULL")); 581155192Srwatson} 582172995Scsjp 583172995Scsjpvoid 584172995Scsjpaudit_proc_coredump(struct thread *td, char *path, int errcode) 585172995Scsjp{ 586172995Scsjp struct kaudit_record *ar; 587172995Scsjp struct au_mask *aumask; 588172995Scsjp au_class_t class; 589172995Scsjp int ret, sorf; 590172995Scsjp char **pathp; 591172995Scsjp au_id_t auid; 592172995Scsjp 593174267Swkoszek ret = 0; 594174267Swkoszek 595172995Scsjp /* 596172995Scsjp * Make sure we are using the correct preselection mask. 597172995Scsjp */ 598172995Scsjp auid = td->td_ucred->cr_audit.ai_auid; 599172995Scsjp if (auid == AU_DEFAUDITID) 600172995Scsjp aumask = &audit_nae_mask; 601172995Scsjp else 602172995Scsjp aumask = &td->td_ucred->cr_audit.ai_mask; 603172995Scsjp /* 604172995Scsjp * It's possible for coredump(9) generation to fail. Make sure that 605172995Scsjp * we handle this case correctly for preselection. 606172995Scsjp */ 607172995Scsjp if (errcode != 0) 608172995Scsjp sorf = AU_PRS_FAILURE; 609172995Scsjp else 610172995Scsjp sorf = AU_PRS_SUCCESS; 611172995Scsjp class = au_event_class(AUE_CORE); 612181604Scsjp if (au_preselect(AUE_CORE, class, aumask, sorf) == 0 && 613181604Scsjp audit_pipe_preselect(auid, AUE_CORE, class, sorf, 0) == 0) 614172995Scsjp return; 615172995Scsjp /* 616172995Scsjp * If we are interested in seeing this audit record, allocate it. 617172995Scsjp * Where possible coredump records should contain a pathname and arg32 618172995Scsjp * (signal) tokens. 619172995Scsjp */ 620172995Scsjp ar = audit_new(AUE_CORE, td); 621172995Scsjp if (path != NULL) { 622172995Scsjp pathp = &ar->k_ar.ar_arg_upath1; 623172995Scsjp *pathp = malloc(MAXPATHLEN, M_AUDITPATH, M_WAITOK); 624176565Srwatson audit_canon_path(td, path, *pathp); 625172995Scsjp ARG_SET_VALID(ar, ARG_UPATH1); 626172995Scsjp } 627172995Scsjp ar->k_ar.ar_arg_signum = td->td_proc->p_sig; 628172995Scsjp ARG_SET_VALID(ar, ARG_SIGNUM); 629172995Scsjp if (errcode != 0) 630172995Scsjp ret = 1; 631172995Scsjp audit_commit(ar, errcode, ret); 632172995Scsjp} 633