1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1986, 1988, 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37 #include <sys/cdefs.h>
38 #include "opt_ddb.h"
39 #include "opt_ekcd.h"
40 #include "opt_kdb.h"
41 #include "opt_panic.h"
42 #include "opt_printf.h"
43 #include "opt_sched.h"
44 #include "opt_watchdog.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bio.h>
49 #include <sys/boottrace.h>
50 #include <sys/buf.h>
51 #include <sys/conf.h>
52 #include <sys/compressor.h>
53 #include <sys/cons.h>
54 #include <sys/disk.h>
55 #include <sys/eventhandler.h>
56 #include <sys/filedesc.h>
57 #include <sys/jail.h>
58 #include <sys/kdb.h>
59 #include <sys/kernel.h>
60 #include <sys/kerneldump.h>
61 #include <sys/kthread.h>
62 #include <sys/ktr.h>
63 #include <sys/malloc.h>
64 #include <sys/mbuf.h>
65 #include <sys/mount.h>
66 #include <sys/priv.h>
67 #include <sys/proc.h>
68 #include <sys/reboot.h>
69 #include <sys/resourcevar.h>
70 #include <sys/rwlock.h>
71 #include <sys/sbuf.h>
72 #include <sys/sched.h>
73 #include <sys/smp.h>
74 #include <sys/sysctl.h>
75 #include <sys/sysproto.h>
76 #include <sys/taskqueue.h>
77 #include <sys/vnode.h>
78 #include <sys/watchdog.h>
79
80 #include <crypto/chacha20/chacha.h>
81 #include <crypto/rijndael/rijndael-api-fst.h>
82 #include <crypto/sha2/sha256.h>
83
84 #include <ddb/ddb.h>
85
86 #include <machine/cpu.h>
87 #include <machine/dump.h>
88 #include <machine/pcb.h>
89 #include <machine/smp.h>
90
91 #include <security/mac/mac_framework.h>
92
93 #include <vm/vm.h>
94 #include <vm/vm_object.h>
95 #include <vm/vm_page.h>
96 #include <vm/vm_pager.h>
97 #include <vm/swap_pager.h>
98
99 #include <sys/signalvar.h>
100
101 static MALLOC_DEFINE(M_DUMPER, "dumper", "dumper block buffer");
102
103 #ifndef PANIC_REBOOT_WAIT_TIME
104 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
105 #endif
106 static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
107 SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RWTUN,
108 &panic_reboot_wait_time, 0,
109 "Seconds to wait before rebooting after a panic");
110 static int reboot_wait_time = 0;
111 SYSCTL_INT(_kern, OID_AUTO, reboot_wait_time, CTLFLAG_RWTUN,
112 &reboot_wait_time, 0,
113 "Seconds to wait before rebooting");
114
115 /*
116 * Note that stdarg.h and the ANSI style va_start macro is used for both
117 * ANSI and traditional C compilers.
118 */
119 #include <machine/stdarg.h>
120
121 #ifdef KDB
122 #ifdef KDB_UNATTENDED
123 int debugger_on_panic = 0;
124 #else
125 int debugger_on_panic = 1;
126 #endif
127 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
128 CTLFLAG_RWTUN, &debugger_on_panic, 0,
129 "Run debugger on kernel panic");
130
131 static bool debugger_on_recursive_panic = false;
132 SYSCTL_BOOL(_debug, OID_AUTO, debugger_on_recursive_panic,
133 CTLFLAG_RWTUN, &debugger_on_recursive_panic, 0,
134 "Run debugger on recursive kernel panic");
135
136 int debugger_on_trap = 0;
137 SYSCTL_INT(_debug, OID_AUTO, debugger_on_trap,
138 CTLFLAG_RWTUN, &debugger_on_trap, 0,
139 "Run debugger on kernel trap before panic");
140
141 #ifdef KDB_TRACE
142 static int trace_on_panic = 1;
143 static bool trace_all_panics = true;
144 #else
145 static int trace_on_panic = 0;
146 static bool trace_all_panics = false;
147 #endif
148 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
149 CTLFLAG_RWTUN | CTLFLAG_SECURE,
150 &trace_on_panic, 0, "Print stack trace on kernel panic");
151 SYSCTL_BOOL(_debug, OID_AUTO, trace_all_panics, CTLFLAG_RWTUN,
152 &trace_all_panics, 0, "Print stack traces on secondary kernel panics");
153 #endif /* KDB */
154
155 static int sync_on_panic = 0;
156 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RWTUN,
157 &sync_on_panic, 0, "Do a sync before rebooting from a panic");
158
159 static bool poweroff_on_panic = 0;
160 SYSCTL_BOOL(_kern, OID_AUTO, poweroff_on_panic, CTLFLAG_RWTUN,
161 &poweroff_on_panic, 0, "Do a power off instead of a reboot on a panic");
162
163 static bool powercycle_on_panic = 0;
164 SYSCTL_BOOL(_kern, OID_AUTO, powercycle_on_panic, CTLFLAG_RWTUN,
165 &powercycle_on_panic, 0, "Do a power cycle instead of a reboot on a panic");
166
167 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
168 "Shutdown environment");
169
170 #ifndef DIAGNOSTIC
171 static int show_busybufs;
172 #else
173 static int show_busybufs = 1;
174 #endif
175 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
176 &show_busybufs, 0,
177 "Show busy buffers during shutdown");
178
179 int suspend_blocked = 0;
180 SYSCTL_INT(_kern, OID_AUTO, suspend_blocked, CTLFLAG_RW,
181 &suspend_blocked, 0, "Block suspend due to a pending shutdown");
182
183 #ifdef EKCD
184 FEATURE(ekcd, "Encrypted kernel crash dumps support");
185
186 MALLOC_DEFINE(M_EKCD, "ekcd", "Encrypted kernel crash dumps data");
187
188 struct kerneldumpcrypto {
189 uint8_t kdc_encryption;
190 uint8_t kdc_iv[KERNELDUMP_IV_MAX_SIZE];
191 union {
192 struct {
193 keyInstance aes_ki;
194 cipherInstance aes_ci;
195 } u_aes;
196 struct chacha_ctx u_chacha;
197 } u;
198 #define kdc_ki u.u_aes.aes_ki
199 #define kdc_ci u.u_aes.aes_ci
200 #define kdc_chacha u.u_chacha
201 uint32_t kdc_dumpkeysize;
202 struct kerneldumpkey kdc_dumpkey[];
203 };
204 #endif
205
206 struct kerneldumpcomp {
207 uint8_t kdc_format;
208 struct compressor *kdc_stream;
209 uint8_t *kdc_buf;
210 size_t kdc_resid;
211 };
212
213 static struct kerneldumpcomp *kerneldumpcomp_create(struct dumperinfo *di,
214 uint8_t compression);
215 static void kerneldumpcomp_destroy(struct dumperinfo *di);
216 static int kerneldumpcomp_write_cb(void *base, size_t len, off_t off, void *arg);
217
218 static int kerneldump_gzlevel = 6;
219 SYSCTL_INT(_kern, OID_AUTO, kerneldump_gzlevel, CTLFLAG_RWTUN,
220 &kerneldump_gzlevel, 0,
221 "Kernel crash dump compression level");
222
223 /*
224 * Variable panicstr contains argument to first call to panic; used as flag
225 * to indicate that the kernel has already called panic.
226 */
227 const char *panicstr __read_mostly;
228 bool scheduler_stopped __read_frequently;
229
230 int dumping __read_mostly; /* system is dumping */
231 int rebooting __read_mostly; /* system is rebooting */
232 bool dumped_core __read_mostly; /* system successfully dumped core */
233 /*
234 * Used to serialize between sysctl kern.shutdown.dumpdevname and list
235 * modifications via ioctl.
236 */
237 static struct mtx dumpconf_list_lk;
238 MTX_SYSINIT(dumper_configs, &dumpconf_list_lk, "dumper config list", MTX_DEF);
239
240 /* Our selected dumper(s). */
241 static TAILQ_HEAD(dumpconflist, dumperinfo) dumper_configs =
242 TAILQ_HEAD_INITIALIZER(dumper_configs);
243
244 /* Context information for dump-debuggers, saved by the dump_savectx() macro. */
245 struct pcb dumppcb; /* Registers. */
246 lwpid_t dumptid; /* Thread ID. */
247
248 static struct cdevsw reroot_cdevsw = {
249 .d_version = D_VERSION,
250 .d_name = "reroot",
251 };
252
253 static void poweroff_wait(void *, int);
254 static void shutdown_halt(void *junk, int howto);
255 static void shutdown_panic(void *junk, int howto);
256 static void shutdown_reset(void *junk, int howto);
257 static int kern_reroot(void);
258
259 /* register various local shutdown events */
260 static void
shutdown_conf(void * unused)261 shutdown_conf(void *unused)
262 {
263
264 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
265 SHUTDOWN_PRI_FIRST);
266 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
267 SHUTDOWN_PRI_LAST + 100);
268 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
269 SHUTDOWN_PRI_LAST + 200);
270 }
271
272 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
273
274 /*
275 * The only reason this exists is to create the /dev/reroot/ directory,
276 * used by reroot code in init(8) as a mountpoint for tmpfs.
277 */
278 static void
reroot_conf(void * unused)279 reroot_conf(void *unused)
280 {
281 int error;
282 struct cdev *cdev;
283
284 error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &cdev,
285 &reroot_cdevsw, NULL, UID_ROOT, GID_WHEEL, 0600, "reroot/reroot");
286 if (error != 0) {
287 printf("%s: failed to create device node, error %d",
288 __func__, error);
289 }
290 }
291
292 SYSINIT(reroot_conf, SI_SUB_DEVFS, SI_ORDER_ANY, reroot_conf, NULL);
293
294 /*
295 * The system call that results in a reboot.
296 */
297 /* ARGSUSED */
298 int
sys_reboot(struct thread * td,struct reboot_args * uap)299 sys_reboot(struct thread *td, struct reboot_args *uap)
300 {
301 int error;
302
303 error = 0;
304 #ifdef MAC
305 error = mac_system_check_reboot(td->td_ucred, uap->opt);
306 #endif
307 if (error == 0)
308 error = priv_check(td, PRIV_REBOOT);
309 if (error == 0) {
310 if (uap->opt & RB_REROOT)
311 error = kern_reroot();
312 else
313 kern_reboot(uap->opt);
314 }
315 return (error);
316 }
317
318 static void
shutdown_nice_task_fn(void * arg,int pending __unused)319 shutdown_nice_task_fn(void *arg, int pending __unused)
320 {
321 int howto;
322
323 howto = (uintptr_t)arg;
324 /* Send a signal to init(8) and have it shutdown the world. */
325 PROC_LOCK(initproc);
326 if ((howto & RB_POWEROFF) != 0) {
327 BOOTTRACE("SIGUSR2 to init(8)");
328 kern_psignal(initproc, SIGUSR2);
329 } else if ((howto & RB_POWERCYCLE) != 0) {
330 BOOTTRACE("SIGWINCH to init(8)");
331 kern_psignal(initproc, SIGWINCH);
332 } else if ((howto & RB_HALT) != 0) {
333 BOOTTRACE("SIGUSR1 to init(8)");
334 kern_psignal(initproc, SIGUSR1);
335 } else {
336 BOOTTRACE("SIGINT to init(8)");
337 kern_psignal(initproc, SIGINT);
338 }
339 PROC_UNLOCK(initproc);
340 }
341
342 static struct task shutdown_nice_task = TASK_INITIALIZER(0,
343 &shutdown_nice_task_fn, NULL);
344
345 /*
346 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
347 */
348 void
shutdown_nice(int howto)349 shutdown_nice(int howto)
350 {
351
352 if (initproc != NULL && !SCHEDULER_STOPPED()) {
353 BOOTTRACE("shutdown initiated");
354 shutdown_nice_task.ta_context = (void *)(uintptr_t)howto;
355 taskqueue_enqueue(taskqueue_fast, &shutdown_nice_task);
356 } else {
357 /*
358 * No init(8) running, or scheduler would not allow it
359 * to run, so simply reboot.
360 */
361 kern_reboot(howto | RB_NOSYNC);
362 }
363 }
364
365 static void
print_uptime(void)366 print_uptime(void)
367 {
368 int f;
369 struct timespec ts;
370
371 getnanouptime(&ts);
372 printf("Uptime: ");
373 f = 0;
374 if (ts.tv_sec >= 86400) {
375 printf("%ldd", (long)ts.tv_sec / 86400);
376 ts.tv_sec %= 86400;
377 f = 1;
378 }
379 if (f || ts.tv_sec >= 3600) {
380 printf("%ldh", (long)ts.tv_sec / 3600);
381 ts.tv_sec %= 3600;
382 f = 1;
383 }
384 if (f || ts.tv_sec >= 60) {
385 printf("%ldm", (long)ts.tv_sec / 60);
386 ts.tv_sec %= 60;
387 f = 1;
388 }
389 printf("%lds\n", (long)ts.tv_sec);
390 }
391
392 int
doadump(boolean_t textdump)393 doadump(boolean_t textdump)
394 {
395 boolean_t coredump;
396 int error;
397
398 error = 0;
399 if (dumping)
400 return (EBUSY);
401 if (TAILQ_EMPTY(&dumper_configs))
402 return (ENXIO);
403
404 dump_savectx();
405 dumping++;
406
407 coredump = TRUE;
408 #ifdef DDB
409 if (textdump && textdump_pending) {
410 coredump = FALSE;
411 textdump_dumpsys(TAILQ_FIRST(&dumper_configs));
412 }
413 #endif
414 if (coredump) {
415 struct dumperinfo *di;
416
417 TAILQ_FOREACH(di, &dumper_configs, di_next) {
418 error = dumpsys(di);
419 if (error == 0) {
420 dumped_core = true;
421 break;
422 }
423 }
424 }
425
426 dumping--;
427 return (error);
428 }
429
430 /*
431 * Trace the shutdown reason.
432 */
433 static void
reboottrace(int howto)434 reboottrace(int howto)
435 {
436 if ((howto & RB_DUMP) != 0) {
437 if ((howto & RB_HALT) != 0)
438 BOOTTRACE("system panic: halting...");
439 if ((howto & RB_POWEROFF) != 0)
440 BOOTTRACE("system panic: powering off...");
441 if ((howto & (RB_HALT|RB_POWEROFF)) == 0)
442 BOOTTRACE("system panic: rebooting...");
443 } else {
444 if ((howto & RB_HALT) != 0)
445 BOOTTRACE("system halting...");
446 if ((howto & RB_POWEROFF) != 0)
447 BOOTTRACE("system powering off...");
448 if ((howto & (RB_HALT|RB_POWEROFF)) == 0)
449 BOOTTRACE("system rebooting...");
450 }
451 }
452
453 /*
454 * kern_reboot(9): Shut down the system cleanly to prepare for reboot, halt, or
455 * power off.
456 */
457 void
kern_reboot(int howto)458 kern_reboot(int howto)
459 {
460 static int once = 0;
461
462 if (initproc != NULL && curproc != initproc)
463 BOOTTRACE("kernel shutdown (dirty) started");
464 else
465 BOOTTRACE("kernel shutdown (clean) started");
466
467 /*
468 * Normal paths here don't hold Giant, but we can wind up here
469 * unexpectedly with it held. Drop it now so we don't have to
470 * drop and pick it up elsewhere. The paths it is locking will
471 * never be returned to, and it is preferable to preclude
472 * deadlock than to lock against code that won't ever
473 * continue.
474 */
475 while (!SCHEDULER_STOPPED() && mtx_owned(&Giant))
476 mtx_unlock(&Giant);
477
478 #if defined(SMP)
479 /*
480 * Bind us to the first CPU so that all shutdown code runs there. Some
481 * systems don't shutdown properly (i.e., ACPI power off) if we
482 * run on another processor.
483 */
484 if (!SCHEDULER_STOPPED()) {
485 thread_lock(curthread);
486 sched_bind(curthread, CPU_FIRST());
487 thread_unlock(curthread);
488 KASSERT(PCPU_GET(cpuid) == CPU_FIRST(),
489 ("%s: not running on cpu 0", __func__));
490 }
491 #endif
492 /* We're in the process of rebooting. */
493 rebooting = 1;
494 reboottrace(howto);
495
496 /*
497 * Do any callouts that should be done BEFORE syncing the filesystems.
498 */
499 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
500 BOOTTRACE("shutdown pre sync complete");
501
502 /*
503 * Now sync filesystems
504 */
505 if (!cold && (howto & RB_NOSYNC) == 0 && once == 0) {
506 once = 1;
507 BOOTTRACE("bufshutdown begin");
508 bufshutdown(show_busybufs);
509 BOOTTRACE("bufshutdown end");
510 }
511
512 print_uptime();
513
514 cngrab();
515
516 /*
517 * Ok, now do things that assume all filesystem activity has
518 * been completed.
519 */
520 EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
521 BOOTTRACE("shutdown post sync complete");
522
523 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
524 doadump(TRUE);
525
526 /* Now that we're going to really halt the system... */
527 BOOTTRACE("shutdown final begin");
528
529 if (shutdown_trace)
530 boottrace_dump_console();
531
532 EVENTHANDLER_INVOKE(shutdown_final, howto);
533
534 /*
535 * Call this directly so that reset is attempted even if shutdown
536 * handlers are not yet registered.
537 */
538 shutdown_reset(NULL, howto);
539
540 for(;;) ; /* safety against shutdown_reset not working */
541 /* NOTREACHED */
542 }
543
544 /*
545 * The system call that results in changing the rootfs.
546 */
547 static int
kern_reroot(void)548 kern_reroot(void)
549 {
550 struct vnode *oldrootvnode, *vp;
551 struct mount *mp, *devmp;
552 int error;
553
554 if (curproc != initproc)
555 return (EPERM);
556
557 /*
558 * Mark the filesystem containing currently-running executable
559 * (the temporary copy of init(8)) busy.
560 */
561 vp = curproc->p_textvp;
562 error = vn_lock(vp, LK_SHARED);
563 if (error != 0)
564 return (error);
565 mp = vp->v_mount;
566 error = vfs_busy(mp, MBF_NOWAIT);
567 if (error != 0) {
568 vfs_ref(mp);
569 VOP_UNLOCK(vp);
570 error = vfs_busy(mp, 0);
571 vn_lock(vp, LK_SHARED | LK_RETRY);
572 vfs_rel(mp);
573 if (error != 0) {
574 VOP_UNLOCK(vp);
575 return (ENOENT);
576 }
577 if (VN_IS_DOOMED(vp)) {
578 VOP_UNLOCK(vp);
579 vfs_unbusy(mp);
580 return (ENOENT);
581 }
582 }
583 VOP_UNLOCK(vp);
584
585 /*
586 * Remove the filesystem containing currently-running executable
587 * from the mount list, to prevent it from being unmounted
588 * by vfs_unmountall(), and to avoid confusing vfs_mountroot().
589 *
590 * Also preserve /dev - forcibly unmounting it could cause driver
591 * reinitialization.
592 */
593
594 vfs_ref(rootdevmp);
595 devmp = rootdevmp;
596 rootdevmp = NULL;
597
598 mtx_lock(&mountlist_mtx);
599 TAILQ_REMOVE(&mountlist, mp, mnt_list);
600 TAILQ_REMOVE(&mountlist, devmp, mnt_list);
601 mtx_unlock(&mountlist_mtx);
602
603 oldrootvnode = rootvnode;
604
605 /*
606 * Unmount everything except for the two filesystems preserved above.
607 */
608 vfs_unmountall();
609
610 /*
611 * Add /dev back; vfs_mountroot() will move it into its new place.
612 */
613 mtx_lock(&mountlist_mtx);
614 TAILQ_INSERT_HEAD(&mountlist, devmp, mnt_list);
615 mtx_unlock(&mountlist_mtx);
616 rootdevmp = devmp;
617 vfs_rel(rootdevmp);
618
619 /*
620 * Mount the new rootfs.
621 */
622 vfs_mountroot();
623
624 /*
625 * Update all references to the old rootvnode.
626 */
627 mountcheckdirs(oldrootvnode, rootvnode);
628
629 /*
630 * Add the temporary filesystem back and unbusy it.
631 */
632 mtx_lock(&mountlist_mtx);
633 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
634 mtx_unlock(&mountlist_mtx);
635 vfs_unbusy(mp);
636
637 return (0);
638 }
639
640 /*
641 * If the shutdown was a clean halt, behave accordingly.
642 */
643 static void
shutdown_halt(void * junk,int howto)644 shutdown_halt(void *junk, int howto)
645 {
646
647 if (howto & RB_HALT) {
648 printf("\n");
649 printf("The operating system has halted.\n");
650 printf("Please press any key to reboot.\n\n");
651
652 wdog_kern_pat(WD_TO_NEVER);
653
654 switch (cngetc()) {
655 case -1: /* No console, just die */
656 cpu_halt();
657 /* NOTREACHED */
658 default:
659 break;
660 }
661 }
662 }
663
664 /*
665 * Check to see if the system panicked, pause and then reboot
666 * according to the specified delay.
667 */
668 static void
shutdown_panic(void * junk,int howto)669 shutdown_panic(void *junk, int howto)
670 {
671 int loop;
672
673 if (howto & RB_DUMP) {
674 if (panic_reboot_wait_time != 0) {
675 if (panic_reboot_wait_time != -1) {
676 printf("Automatic reboot in %d seconds - "
677 "press a key on the console to abort\n",
678 panic_reboot_wait_time);
679 for (loop = panic_reboot_wait_time * 10;
680 loop > 0; --loop) {
681 DELAY(1000 * 100); /* 1/10th second */
682 /* Did user type a key? */
683 if (cncheckc() != -1)
684 break;
685 }
686 if (!loop)
687 return;
688 }
689 } else { /* zero time specified - reboot NOW */
690 return;
691 }
692 printf("--> Press a key on the console to reboot,\n");
693 printf("--> or switch off the system now.\n");
694 cngetc();
695 }
696 }
697
698 /*
699 * Everything done, now reset
700 */
701 static void
shutdown_reset(void * junk,int howto)702 shutdown_reset(void *junk, int howto)
703 {
704
705 printf("Rebooting...\n");
706 DELAY(reboot_wait_time * 1000000);
707
708 /*
709 * Acquiring smp_ipi_mtx here has a double effect:
710 * - it disables interrupts avoiding CPU0 preemption
711 * by fast handlers (thus deadlocking against other CPUs)
712 * - it avoids deadlocks against smp_rendezvous() or, more
713 * generally, threads busy-waiting, with this spinlock held,
714 * and waiting for responses by threads on other CPUs
715 * (ie. smp_tlb_shootdown()).
716 *
717 * For the !SMP case it just needs to handle the former problem.
718 */
719 #ifdef SMP
720 mtx_lock_spin(&smp_ipi_mtx);
721 #else
722 spinlock_enter();
723 #endif
724
725 cpu_reset();
726 /* NOTREACHED */ /* assuming reset worked */
727 }
728
729 #if defined(WITNESS) || defined(INVARIANT_SUPPORT)
730 static int kassert_warn_only = 0;
731 #ifdef KDB
732 static int kassert_do_kdb = 0;
733 #endif
734 #ifdef KTR
735 static int kassert_do_ktr = 0;
736 #endif
737 static int kassert_do_log = 1;
738 static int kassert_log_pps_limit = 4;
739 static int kassert_log_mute_at = 0;
740 static int kassert_log_panic_at = 0;
741 static int kassert_suppress_in_panic = 0;
742 static int kassert_warnings = 0;
743
744 SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
745 "kassert options");
746
747 #ifdef KASSERT_PANIC_OPTIONAL
748 #define KASSERT_RWTUN CTLFLAG_RWTUN
749 #else
750 #define KASSERT_RWTUN CTLFLAG_RDTUN
751 #endif
752
753 SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, KASSERT_RWTUN,
754 &kassert_warn_only, 0,
755 "KASSERT triggers a panic (0) or just a warning (1)");
756
757 #ifdef KDB
758 SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, KASSERT_RWTUN,
759 &kassert_do_kdb, 0, "KASSERT will enter the debugger");
760 #endif
761
762 #ifdef KTR
763 SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, KASSERT_RWTUN,
764 &kassert_do_ktr, 0,
765 "KASSERT does a KTR, set this to the KTRMASK you want");
766 #endif
767
768 SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, KASSERT_RWTUN,
769 &kassert_do_log, 0,
770 "If warn_only is enabled, log (1) or do not log (0) assertion violations");
771
772 SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RD | CTLFLAG_STATS,
773 &kassert_warnings, 0, "number of KASSERTs that have been triggered");
774
775 SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, KASSERT_RWTUN,
776 &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic");
777
778 SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, KASSERT_RWTUN,
779 &kassert_log_pps_limit, 0, "limit number of log messages per second");
780
781 SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, KASSERT_RWTUN,
782 &kassert_log_mute_at, 0, "max number of KASSERTS to log");
783
784 SYSCTL_INT(_debug_kassert, OID_AUTO, suppress_in_panic, KASSERT_RWTUN,
785 &kassert_suppress_in_panic, 0,
786 "KASSERTs will be suppressed while handling a panic");
787 #undef KASSERT_RWTUN
788
789 static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS);
790
791 SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert,
792 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_MPSAFE, NULL, 0,
793 kassert_sysctl_kassert, "I",
794 "set to trigger a test kassert");
795
796 static int
kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS)797 kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS)
798 {
799 int error, i;
800
801 error = sysctl_wire_old_buffer(req, sizeof(int));
802 if (error == 0) {
803 i = 0;
804 error = sysctl_handle_int(oidp, &i, 0, req);
805 }
806 if (error != 0 || req->newptr == NULL)
807 return (error);
808 KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i));
809 return (0);
810 }
811
812 #ifdef KASSERT_PANIC_OPTIONAL
813 /*
814 * Called by KASSERT, this decides if we will panic
815 * or if we will log via printf and/or ktr.
816 */
817 void
kassert_panic(const char * fmt,...)818 kassert_panic(const char *fmt, ...)
819 {
820 static char buf[256];
821 va_list ap;
822
823 va_start(ap, fmt);
824 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
825 va_end(ap);
826
827 /*
828 * If we are suppressing secondary panics, log the warning but do not
829 * re-enter panic/kdb.
830 */
831 if (KERNEL_PANICKED() && kassert_suppress_in_panic) {
832 if (kassert_do_log) {
833 printf("KASSERT failed: %s\n", buf);
834 #ifdef KDB
835 if (trace_all_panics && trace_on_panic)
836 kdb_backtrace();
837 #endif
838 }
839 return;
840 }
841
842 /*
843 * panic if we're not just warning, or if we've exceeded
844 * kassert_log_panic_at warnings.
845 */
846 if (!kassert_warn_only ||
847 (kassert_log_panic_at > 0 &&
848 kassert_warnings >= kassert_log_panic_at)) {
849 va_start(ap, fmt);
850 vpanic(fmt, ap);
851 /* NORETURN */
852 }
853 #ifdef KTR
854 if (kassert_do_ktr)
855 CTR0(ktr_mask, buf);
856 #endif /* KTR */
857 /*
858 * log if we've not yet met the mute limit.
859 */
860 if (kassert_do_log &&
861 (kassert_log_mute_at == 0 ||
862 kassert_warnings < kassert_log_mute_at)) {
863 static struct timeval lasterr;
864 static int curerr;
865
866 if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) {
867 printf("KASSERT failed: %s\n", buf);
868 kdb_backtrace();
869 }
870 }
871 #ifdef KDB
872 if (kassert_do_kdb) {
873 kdb_enter(KDB_WHY_KASSERT, buf);
874 }
875 #endif
876 atomic_add_int(&kassert_warnings, 1);
877 }
878 #endif /* KASSERT_PANIC_OPTIONAL */
879 #endif
880
881 /*
882 * Panic is called on unresolvable fatal errors. It prints "panic: mesg",
883 * and then reboots. If we are called twice, then we avoid trying to sync
884 * the disks as this often leads to recursive panics.
885 */
886 void
panic(const char * fmt,...)887 panic(const char *fmt, ...)
888 {
889 va_list ap;
890
891 va_start(ap, fmt);
892 vpanic(fmt, ap);
893 }
894
895 void
vpanic(const char * fmt,va_list ap)896 vpanic(const char *fmt, va_list ap)
897 {
898 #ifdef SMP
899 cpuset_t other_cpus;
900 #endif
901 struct thread *td = curthread;
902 int bootopt, newpanic;
903 static char buf[256];
904
905 /*
906 * 'fmt' must not be NULL as it is put into 'panicstr' which is then
907 * used as a flag to detect if the kernel has panicked. Also, although
908 * vsnprintf() supports a NULL 'fmt' argument, use a more informative
909 * message.
910 */
911 if (fmt == NULL)
912 fmt = "<no panic string!>";
913
914 spinlock_enter();
915
916 #ifdef SMP
917 /*
918 * stop_cpus_hard(other_cpus) should prevent multiple CPUs from
919 * concurrently entering panic. Only the winner will proceed
920 * further.
921 */
922 if (!KERNEL_PANICKED() && !kdb_active) {
923 other_cpus = all_cpus;
924 CPU_CLR(PCPU_GET(cpuid), &other_cpus);
925 stop_cpus_hard(other_cpus);
926 }
927 #endif
928
929 /*
930 * Ensure that the scheduler is stopped while panicking, even if panic
931 * has been entered from kdb.
932 */
933 scheduler_stopped = true;
934
935 bootopt = RB_AUTOBOOT;
936 newpanic = 0;
937 if (KERNEL_PANICKED())
938 bootopt |= RB_NOSYNC;
939 else {
940 bootopt |= RB_DUMP;
941 panicstr = fmt;
942 newpanic = 1;
943 }
944
945 /* Unmute when panic */
946 cn_mute = 0;
947
948 if (newpanic) {
949 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
950 panicstr = buf;
951 cngrab();
952 printf("panic: %s\n", buf);
953 } else {
954 printf("panic: ");
955 vprintf(fmt, ap);
956 printf("\n");
957 }
958 #ifdef SMP
959 printf("cpuid = %d\n", PCPU_GET(cpuid));
960 #endif
961 printf("time = %jd\n", (intmax_t )time_second);
962 #ifdef KDB
963 if ((newpanic || trace_all_panics) && trace_on_panic)
964 kdb_backtrace();
965 if (debugger_on_panic)
966 kdb_enter(KDB_WHY_PANIC, "panic");
967 else if (!newpanic && debugger_on_recursive_panic)
968 kdb_enter(KDB_WHY_PANIC, "re-panic");
969 #endif
970 /*thread_lock(td); */
971 td->td_flags |= TDF_INPANIC;
972 /* thread_unlock(td); */
973 if (!sync_on_panic)
974 bootopt |= RB_NOSYNC;
975 if (poweroff_on_panic)
976 bootopt |= RB_POWEROFF;
977 if (powercycle_on_panic)
978 bootopt |= RB_POWERCYCLE;
979 kern_reboot(bootopt);
980 }
981
982 /*
983 * Support for poweroff delay.
984 *
985 * Please note that setting this delay too short might power off your machine
986 * before the write cache on your hard disk has been flushed, leading to
987 * soft-updates inconsistencies.
988 */
989 #ifndef POWEROFF_DELAY
990 # define POWEROFF_DELAY 5000
991 #endif
992 static int poweroff_delay = POWEROFF_DELAY;
993
994 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
995 &poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)");
996
997 static void
poweroff_wait(void * junk,int howto)998 poweroff_wait(void *junk, int howto)
999 {
1000
1001 if ((howto & (RB_POWEROFF | RB_POWERCYCLE)) == 0 || poweroff_delay <= 0)
1002 return;
1003 DELAY(poweroff_delay * 1000);
1004 }
1005
1006 /*
1007 * Some system processes (e.g. syncer) need to be stopped at appropriate
1008 * points in their main loops prior to a system shutdown, so that they
1009 * won't interfere with the shutdown process (e.g. by holding a disk buf
1010 * to cause sync to fail). For each of these system processes, register
1011 * shutdown_kproc() as a handler for one of shutdown events.
1012 */
1013 static int kproc_shutdown_wait = 60;
1014 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
1015 &kproc_shutdown_wait, 0, "Max wait time (sec) to stop for each process");
1016
1017 void
kproc_shutdown(void * arg,int howto)1018 kproc_shutdown(void *arg, int howto)
1019 {
1020 struct proc *p;
1021 int error;
1022
1023 if (SCHEDULER_STOPPED())
1024 return;
1025
1026 p = (struct proc *)arg;
1027 printf("Waiting (max %d seconds) for system process `%s' to stop... ",
1028 kproc_shutdown_wait, p->p_comm);
1029 error = kproc_suspend(p, kproc_shutdown_wait * hz);
1030
1031 if (error == EWOULDBLOCK)
1032 printf("timed out\n");
1033 else
1034 printf("done\n");
1035 }
1036
1037 void
kthread_shutdown(void * arg,int howto)1038 kthread_shutdown(void *arg, int howto)
1039 {
1040 struct thread *td;
1041 int error;
1042
1043 if (SCHEDULER_STOPPED())
1044 return;
1045
1046 td = (struct thread *)arg;
1047 printf("Waiting (max %d seconds) for system thread `%s' to stop... ",
1048 kproc_shutdown_wait, td->td_name);
1049 error = kthread_suspend(td, kproc_shutdown_wait * hz);
1050
1051 if (error == EWOULDBLOCK)
1052 printf("timed out\n");
1053 else
1054 printf("done\n");
1055 }
1056
1057 static int
dumpdevname_sysctl_handler(SYSCTL_HANDLER_ARGS)1058 dumpdevname_sysctl_handler(SYSCTL_HANDLER_ARGS)
1059 {
1060 char buf[256];
1061 struct dumperinfo *di;
1062 struct sbuf sb;
1063 int error;
1064
1065 error = sysctl_wire_old_buffer(req, 0);
1066 if (error != 0)
1067 return (error);
1068
1069 sbuf_new_for_sysctl(&sb, buf, sizeof(buf), req);
1070
1071 mtx_lock(&dumpconf_list_lk);
1072 TAILQ_FOREACH(di, &dumper_configs, di_next) {
1073 if (di != TAILQ_FIRST(&dumper_configs))
1074 sbuf_putc(&sb, ',');
1075 sbuf_cat(&sb, di->di_devname);
1076 }
1077 mtx_unlock(&dumpconf_list_lk);
1078
1079 error = sbuf_finish(&sb);
1080 sbuf_delete(&sb);
1081 return (error);
1082 }
1083 SYSCTL_PROC(_kern_shutdown, OID_AUTO, dumpdevname,
1084 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, &dumper_configs, 0,
1085 dumpdevname_sysctl_handler, "A",
1086 "Device(s) for kernel dumps");
1087
1088 static int _dump_append(struct dumperinfo *di, void *virtual, size_t length);
1089
1090 #ifdef EKCD
1091 static struct kerneldumpcrypto *
kerneldumpcrypto_create(size_t blocksize,uint8_t encryption,const uint8_t * key,uint32_t encryptedkeysize,const uint8_t * encryptedkey)1092 kerneldumpcrypto_create(size_t blocksize, uint8_t encryption,
1093 const uint8_t *key, uint32_t encryptedkeysize, const uint8_t *encryptedkey)
1094 {
1095 struct kerneldumpcrypto *kdc;
1096 struct kerneldumpkey *kdk;
1097 uint32_t dumpkeysize;
1098
1099 dumpkeysize = roundup2(sizeof(*kdk) + encryptedkeysize, blocksize);
1100 kdc = malloc(sizeof(*kdc) + dumpkeysize, M_EKCD, M_WAITOK | M_ZERO);
1101
1102 arc4rand(kdc->kdc_iv, sizeof(kdc->kdc_iv), 0);
1103
1104 kdc->kdc_encryption = encryption;
1105 switch (kdc->kdc_encryption) {
1106 case KERNELDUMP_ENC_AES_256_CBC:
1107 if (rijndael_makeKey(&kdc->kdc_ki, DIR_ENCRYPT, 256, key) <= 0)
1108 goto failed;
1109 break;
1110 case KERNELDUMP_ENC_CHACHA20:
1111 chacha_keysetup(&kdc->kdc_chacha, key, 256);
1112 break;
1113 default:
1114 goto failed;
1115 }
1116
1117 kdc->kdc_dumpkeysize = dumpkeysize;
1118 kdk = kdc->kdc_dumpkey;
1119 kdk->kdk_encryption = kdc->kdc_encryption;
1120 memcpy(kdk->kdk_iv, kdc->kdc_iv, sizeof(kdk->kdk_iv));
1121 kdk->kdk_encryptedkeysize = htod32(encryptedkeysize);
1122 memcpy(kdk->kdk_encryptedkey, encryptedkey, encryptedkeysize);
1123
1124 return (kdc);
1125 failed:
1126 zfree(kdc, M_EKCD);
1127 return (NULL);
1128 }
1129
1130 static int
kerneldumpcrypto_init(struct kerneldumpcrypto * kdc)1131 kerneldumpcrypto_init(struct kerneldumpcrypto *kdc)
1132 {
1133 uint8_t hash[SHA256_DIGEST_LENGTH];
1134 SHA256_CTX ctx;
1135 struct kerneldumpkey *kdk;
1136 int error;
1137
1138 error = 0;
1139
1140 if (kdc == NULL)
1141 return (0);
1142
1143 /*
1144 * When a user enters ddb it can write a crash dump multiple times.
1145 * Each time it should be encrypted using a different IV.
1146 */
1147 SHA256_Init(&ctx);
1148 SHA256_Update(&ctx, kdc->kdc_iv, sizeof(kdc->kdc_iv));
1149 SHA256_Final(hash, &ctx);
1150 bcopy(hash, kdc->kdc_iv, sizeof(kdc->kdc_iv));
1151
1152 switch (kdc->kdc_encryption) {
1153 case KERNELDUMP_ENC_AES_256_CBC:
1154 if (rijndael_cipherInit(&kdc->kdc_ci, MODE_CBC,
1155 kdc->kdc_iv) <= 0) {
1156 error = EINVAL;
1157 goto out;
1158 }
1159 break;
1160 case KERNELDUMP_ENC_CHACHA20:
1161 chacha_ivsetup(&kdc->kdc_chacha, kdc->kdc_iv, NULL);
1162 break;
1163 default:
1164 error = EINVAL;
1165 goto out;
1166 }
1167
1168 kdk = kdc->kdc_dumpkey;
1169 memcpy(kdk->kdk_iv, kdc->kdc_iv, sizeof(kdk->kdk_iv));
1170 out:
1171 explicit_bzero(hash, sizeof(hash));
1172 return (error);
1173 }
1174
1175 static uint32_t
kerneldumpcrypto_dumpkeysize(const struct kerneldumpcrypto * kdc)1176 kerneldumpcrypto_dumpkeysize(const struct kerneldumpcrypto *kdc)
1177 {
1178
1179 if (kdc == NULL)
1180 return (0);
1181 return (kdc->kdc_dumpkeysize);
1182 }
1183 #endif /* EKCD */
1184
1185 static struct kerneldumpcomp *
kerneldumpcomp_create(struct dumperinfo * di,uint8_t compression)1186 kerneldumpcomp_create(struct dumperinfo *di, uint8_t compression)
1187 {
1188 struct kerneldumpcomp *kdcomp;
1189 int format;
1190
1191 switch (compression) {
1192 case KERNELDUMP_COMP_GZIP:
1193 format = COMPRESS_GZIP;
1194 break;
1195 case KERNELDUMP_COMP_ZSTD:
1196 format = COMPRESS_ZSTD;
1197 break;
1198 default:
1199 return (NULL);
1200 }
1201
1202 kdcomp = malloc(sizeof(*kdcomp), M_DUMPER, M_WAITOK | M_ZERO);
1203 kdcomp->kdc_format = compression;
1204 kdcomp->kdc_stream = compressor_init(kerneldumpcomp_write_cb,
1205 format, di->maxiosize, kerneldump_gzlevel, di);
1206 if (kdcomp->kdc_stream == NULL) {
1207 free(kdcomp, M_DUMPER);
1208 return (NULL);
1209 }
1210 kdcomp->kdc_buf = malloc(di->maxiosize, M_DUMPER, M_WAITOK | M_NODUMP);
1211 return (kdcomp);
1212 }
1213
1214 static void
kerneldumpcomp_destroy(struct dumperinfo * di)1215 kerneldumpcomp_destroy(struct dumperinfo *di)
1216 {
1217 struct kerneldumpcomp *kdcomp;
1218
1219 kdcomp = di->kdcomp;
1220 if (kdcomp == NULL)
1221 return;
1222 compressor_fini(kdcomp->kdc_stream);
1223 zfree(kdcomp->kdc_buf, M_DUMPER);
1224 free(kdcomp, M_DUMPER);
1225 }
1226
1227 /*
1228 * Free a dumper. Must not be present on global list.
1229 */
1230 void
dumper_destroy(struct dumperinfo * di)1231 dumper_destroy(struct dumperinfo *di)
1232 {
1233
1234 if (di == NULL)
1235 return;
1236
1237 zfree(di->blockbuf, M_DUMPER);
1238 kerneldumpcomp_destroy(di);
1239 #ifdef EKCD
1240 zfree(di->kdcrypto, M_EKCD);
1241 #endif
1242 zfree(di, M_DUMPER);
1243 }
1244
1245 /*
1246 * Allocate and set up a new dumper from the provided template.
1247 */
1248 int
dumper_create(const struct dumperinfo * di_template,const char * devname,const struct diocskerneldump_arg * kda,struct dumperinfo ** dip)1249 dumper_create(const struct dumperinfo *di_template, const char *devname,
1250 const struct diocskerneldump_arg *kda, struct dumperinfo **dip)
1251 {
1252 struct dumperinfo *newdi;
1253 int error = 0;
1254
1255 if (dip == NULL)
1256 return (EINVAL);
1257
1258 /* Allocate a new dumper */
1259 newdi = malloc(sizeof(*newdi) + strlen(devname) + 1, M_DUMPER,
1260 M_WAITOK | M_ZERO);
1261 memcpy(newdi, di_template, sizeof(*newdi));
1262 newdi->blockbuf = NULL;
1263 newdi->kdcrypto = NULL;
1264 newdi->kdcomp = NULL;
1265 strcpy(newdi->di_devname, devname);
1266
1267 if (kda->kda_encryption != KERNELDUMP_ENC_NONE) {
1268 #ifdef EKCD
1269 newdi->kdcrypto = kerneldumpcrypto_create(newdi->blocksize,
1270 kda->kda_encryption, kda->kda_key,
1271 kda->kda_encryptedkeysize, kda->kda_encryptedkey);
1272 if (newdi->kdcrypto == NULL) {
1273 error = EINVAL;
1274 goto cleanup;
1275 }
1276 #else
1277 error = EOPNOTSUPP;
1278 goto cleanup;
1279 #endif
1280 }
1281 if (kda->kda_compression != KERNELDUMP_COMP_NONE) {
1282 #ifdef EKCD
1283 /*
1284 * We can't support simultaneous unpadded block cipher
1285 * encryption and compression because there is no guarantee the
1286 * length of the compressed result is exactly a multiple of the
1287 * cipher block size.
1288 */
1289 if (kda->kda_encryption == KERNELDUMP_ENC_AES_256_CBC) {
1290 error = EOPNOTSUPP;
1291 goto cleanup;
1292 }
1293 #endif
1294 newdi->kdcomp = kerneldumpcomp_create(newdi,
1295 kda->kda_compression);
1296 if (newdi->kdcomp == NULL) {
1297 error = EINVAL;
1298 goto cleanup;
1299 }
1300 }
1301 newdi->blockbuf = malloc(newdi->blocksize, M_DUMPER, M_WAITOK | M_ZERO);
1302
1303 *dip = newdi;
1304 return (0);
1305 cleanup:
1306 dumper_destroy(newdi);
1307 return (error);
1308 }
1309
1310 /*
1311 * Create a new dumper and register it in the global list.
1312 */
1313 int
dumper_insert(const struct dumperinfo * di_template,const char * devname,const struct diocskerneldump_arg * kda)1314 dumper_insert(const struct dumperinfo *di_template, const char *devname,
1315 const struct diocskerneldump_arg *kda)
1316 {
1317 struct dumperinfo *newdi, *listdi;
1318 bool inserted;
1319 uint8_t index;
1320 int error;
1321
1322 index = kda->kda_index;
1323 MPASS(index != KDA_REMOVE && index != KDA_REMOVE_DEV &&
1324 index != KDA_REMOVE_ALL);
1325
1326 error = priv_check(curthread, PRIV_SETDUMPER);
1327 if (error != 0)
1328 return (error);
1329
1330 error = dumper_create(di_template, devname, kda, &newdi);
1331 if (error != 0)
1332 return (error);
1333
1334 /* Add the new configuration to the queue */
1335 mtx_lock(&dumpconf_list_lk);
1336 inserted = false;
1337 TAILQ_FOREACH(listdi, &dumper_configs, di_next) {
1338 if (index == 0) {
1339 TAILQ_INSERT_BEFORE(listdi, newdi, di_next);
1340 inserted = true;
1341 break;
1342 }
1343 index--;
1344 }
1345 if (!inserted)
1346 TAILQ_INSERT_TAIL(&dumper_configs, newdi, di_next);
1347 mtx_unlock(&dumpconf_list_lk);
1348
1349 return (0);
1350 }
1351
1352 #ifdef DDB
1353 void
dumper_ddb_insert(struct dumperinfo * newdi)1354 dumper_ddb_insert(struct dumperinfo *newdi)
1355 {
1356 TAILQ_INSERT_HEAD(&dumper_configs, newdi, di_next);
1357 }
1358
1359 void
dumper_ddb_remove(struct dumperinfo * di)1360 dumper_ddb_remove(struct dumperinfo *di)
1361 {
1362 TAILQ_REMOVE(&dumper_configs, di, di_next);
1363 }
1364 #endif
1365
1366 static bool
dumper_config_match(const struct dumperinfo * di,const char * devname,const struct diocskerneldump_arg * kda)1367 dumper_config_match(const struct dumperinfo *di, const char *devname,
1368 const struct diocskerneldump_arg *kda)
1369 {
1370 if (kda->kda_index == KDA_REMOVE_ALL)
1371 return (true);
1372
1373 if (strcmp(di->di_devname, devname) != 0)
1374 return (false);
1375
1376 /*
1377 * Allow wildcard removal of configs matching a device on g_dev_orphan.
1378 */
1379 if (kda->kda_index == KDA_REMOVE_DEV)
1380 return (true);
1381
1382 if (di->kdcomp != NULL) {
1383 if (di->kdcomp->kdc_format != kda->kda_compression)
1384 return (false);
1385 } else if (kda->kda_compression != KERNELDUMP_COMP_NONE)
1386 return (false);
1387 #ifdef EKCD
1388 if (di->kdcrypto != NULL) {
1389 if (di->kdcrypto->kdc_encryption != kda->kda_encryption)
1390 return (false);
1391 /*
1392 * Do we care to verify keys match to delete? It seems weird
1393 * to expect multiple fallback dump configurations on the same
1394 * device that only differ in crypto key.
1395 */
1396 } else
1397 #endif
1398 if (kda->kda_encryption != KERNELDUMP_ENC_NONE)
1399 return (false);
1400
1401 return (true);
1402 }
1403
1404 /*
1405 * Remove and free the requested dumper(s) from the global list.
1406 */
1407 int
dumper_remove(const char * devname,const struct diocskerneldump_arg * kda)1408 dumper_remove(const char *devname, const struct diocskerneldump_arg *kda)
1409 {
1410 struct dumperinfo *di, *sdi;
1411 bool found;
1412 int error;
1413
1414 error = priv_check(curthread, PRIV_SETDUMPER);
1415 if (error != 0)
1416 return (error);
1417
1418 /*
1419 * Try to find a matching configuration, and kill it.
1420 *
1421 * NULL 'kda' indicates remove any configuration matching 'devname',
1422 * which may remove multiple configurations in atypical configurations.
1423 */
1424 found = false;
1425 mtx_lock(&dumpconf_list_lk);
1426 TAILQ_FOREACH_SAFE(di, &dumper_configs, di_next, sdi) {
1427 if (dumper_config_match(di, devname, kda)) {
1428 found = true;
1429 TAILQ_REMOVE(&dumper_configs, di, di_next);
1430 dumper_destroy(di);
1431 }
1432 }
1433 mtx_unlock(&dumpconf_list_lk);
1434
1435 /* Only produce ENOENT if a more targeted match didn't match. */
1436 if (!found && kda->kda_index == KDA_REMOVE)
1437 return (ENOENT);
1438 return (0);
1439 }
1440
1441 static int
dump_check_bounds(struct dumperinfo * di,off_t offset,size_t length)1442 dump_check_bounds(struct dumperinfo *di, off_t offset, size_t length)
1443 {
1444
1445 if (di->mediasize > 0 && length != 0 && (offset < di->mediaoffset ||
1446 offset - di->mediaoffset + length > di->mediasize)) {
1447 if (di->kdcomp != NULL && offset >= di->mediaoffset) {
1448 printf(
1449 "Compressed dump failed to fit in device boundaries.\n");
1450 return (E2BIG);
1451 }
1452
1453 printf("Attempt to write outside dump device boundaries.\n"
1454 "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
1455 (intmax_t)offset, (intmax_t)di->mediaoffset,
1456 (uintmax_t)length, (intmax_t)di->mediasize);
1457 return (ENOSPC);
1458 }
1459 if (length % di->blocksize != 0) {
1460 printf("Attempt to write partial block of length %ju.\n",
1461 (uintmax_t)length);
1462 return (EINVAL);
1463 }
1464 if (offset % di->blocksize != 0) {
1465 printf("Attempt to write at unaligned offset %jd.\n",
1466 (intmax_t)offset);
1467 return (EINVAL);
1468 }
1469
1470 return (0);
1471 }
1472
1473 #ifdef EKCD
1474 static int
dump_encrypt(struct kerneldumpcrypto * kdc,uint8_t * buf,size_t size)1475 dump_encrypt(struct kerneldumpcrypto *kdc, uint8_t *buf, size_t size)
1476 {
1477
1478 switch (kdc->kdc_encryption) {
1479 case KERNELDUMP_ENC_AES_256_CBC:
1480 if (rijndael_blockEncrypt(&kdc->kdc_ci, &kdc->kdc_ki, buf,
1481 8 * size, buf) <= 0) {
1482 return (EIO);
1483 }
1484 if (rijndael_cipherInit(&kdc->kdc_ci, MODE_CBC,
1485 buf + size - 16 /* IV size for AES-256-CBC */) <= 0) {
1486 return (EIO);
1487 }
1488 break;
1489 case KERNELDUMP_ENC_CHACHA20:
1490 chacha_encrypt_bytes(&kdc->kdc_chacha, buf, buf, size);
1491 break;
1492 default:
1493 return (EINVAL);
1494 }
1495
1496 return (0);
1497 }
1498
1499 /* Encrypt data and call dumper. */
1500 static int
dump_encrypted_write(struct dumperinfo * di,void * virtual,off_t offset,size_t length)1501 dump_encrypted_write(struct dumperinfo *di, void *virtual, off_t offset,
1502 size_t length)
1503 {
1504 static uint8_t buf[KERNELDUMP_BUFFER_SIZE];
1505 struct kerneldumpcrypto *kdc;
1506 int error;
1507 size_t nbytes;
1508
1509 kdc = di->kdcrypto;
1510
1511 while (length > 0) {
1512 nbytes = MIN(length, sizeof(buf));
1513 bcopy(virtual, buf, nbytes);
1514
1515 if (dump_encrypt(kdc, buf, nbytes) != 0)
1516 return (EIO);
1517
1518 error = dump_write(di, buf, offset, nbytes);
1519 if (error != 0)
1520 return (error);
1521
1522 offset += nbytes;
1523 virtual = (void *)((uint8_t *)virtual + nbytes);
1524 length -= nbytes;
1525 }
1526
1527 return (0);
1528 }
1529 #endif /* EKCD */
1530
1531 static int
kerneldumpcomp_write_cb(void * base,size_t length,off_t offset,void * arg)1532 kerneldumpcomp_write_cb(void *base, size_t length, off_t offset, void *arg)
1533 {
1534 struct dumperinfo *di;
1535 size_t resid, rlength;
1536 int error;
1537
1538 di = arg;
1539
1540 if (length % di->blocksize != 0) {
1541 /*
1542 * This must be the final write after flushing the compression
1543 * stream. Write as many full blocks as possible and stash the
1544 * residual data in the dumper's block buffer. It will be
1545 * padded and written in dump_finish().
1546 */
1547 rlength = rounddown(length, di->blocksize);
1548 if (rlength != 0) {
1549 error = _dump_append(di, base, rlength);
1550 if (error != 0)
1551 return (error);
1552 }
1553 resid = length - rlength;
1554 memmove(di->blockbuf, (uint8_t *)base + rlength, resid);
1555 bzero((uint8_t *)di->blockbuf + resid, di->blocksize - resid);
1556 di->kdcomp->kdc_resid = resid;
1557 return (EAGAIN);
1558 }
1559 return (_dump_append(di, base, length));
1560 }
1561
1562 /*
1563 * Write kernel dump headers at the beginning and end of the dump extent.
1564 * Write the kernel dump encryption key after the leading header if we were
1565 * configured to do so.
1566 */
1567 static int
dump_write_headers(struct dumperinfo * di,struct kerneldumpheader * kdh)1568 dump_write_headers(struct dumperinfo *di, struct kerneldumpheader *kdh)
1569 {
1570 #ifdef EKCD
1571 struct kerneldumpcrypto *kdc;
1572 #endif
1573 void *buf;
1574 size_t hdrsz;
1575 uint64_t extent;
1576 uint32_t keysize;
1577 int error;
1578
1579 hdrsz = sizeof(*kdh);
1580 if (hdrsz > di->blocksize)
1581 return (ENOMEM);
1582
1583 #ifdef EKCD
1584 kdc = di->kdcrypto;
1585 keysize = kerneldumpcrypto_dumpkeysize(kdc);
1586 #else
1587 keysize = 0;
1588 #endif
1589
1590 /*
1591 * If the dump device has special handling for headers, let it take care
1592 * of writing them out.
1593 */
1594 if (di->dumper_hdr != NULL)
1595 return (di->dumper_hdr(di, kdh));
1596
1597 if (hdrsz == di->blocksize)
1598 buf = kdh;
1599 else {
1600 buf = di->blockbuf;
1601 memset(buf, 0, di->blocksize);
1602 memcpy(buf, kdh, hdrsz);
1603 }
1604
1605 extent = dtoh64(kdh->dumpextent);
1606 #ifdef EKCD
1607 if (kdc != NULL) {
1608 error = dump_write(di, kdc->kdc_dumpkey,
1609 di->mediaoffset + di->mediasize - di->blocksize - extent -
1610 keysize, keysize);
1611 if (error != 0)
1612 return (error);
1613 }
1614 #endif
1615
1616 error = dump_write(di, buf,
1617 di->mediaoffset + di->mediasize - 2 * di->blocksize - extent -
1618 keysize, di->blocksize);
1619 if (error == 0)
1620 error = dump_write(di, buf, di->mediaoffset + di->mediasize -
1621 di->blocksize, di->blocksize);
1622 return (error);
1623 }
1624
1625 /*
1626 * Don't touch the first SIZEOF_METADATA bytes on the dump device. This is to
1627 * protect us from metadata and metadata from us.
1628 */
1629 #define SIZEOF_METADATA (64 * 1024)
1630
1631 /*
1632 * Do some preliminary setup for a kernel dump: initialize state for encryption,
1633 * if requested, and make sure that we have enough space on the dump device.
1634 *
1635 * We set things up so that the dump ends before the last sector of the dump
1636 * device, at which the trailing header is written.
1637 *
1638 * +-----------+------+-----+----------------------------+------+
1639 * | | lhdr | key | ... kernel dump ... | thdr |
1640 * +-----------+------+-----+----------------------------+------+
1641 * 1 blk opt <------- dump extent --------> 1 blk
1642 *
1643 * Dumps written using dump_append() start at the beginning of the extent.
1644 * Uncompressed dumps will use the entire extent, but compressed dumps typically
1645 * will not. The true length of the dump is recorded in the leading and trailing
1646 * headers once the dump has been completed.
1647 *
1648 * The dump device may provide a callback, in which case it will initialize
1649 * dumpoff and take care of laying out the headers.
1650 */
1651 int
dump_start(struct dumperinfo * di,struct kerneldumpheader * kdh)1652 dump_start(struct dumperinfo *di, struct kerneldumpheader *kdh)
1653 {
1654 #ifdef EKCD
1655 struct kerneldumpcrypto *kdc;
1656 #endif
1657 void *key;
1658 uint64_t dumpextent, span;
1659 uint32_t keysize;
1660 int error;
1661
1662 #ifdef EKCD
1663 /* Send the key before the dump so a partial dump is still usable. */
1664 kdc = di->kdcrypto;
1665 error = kerneldumpcrypto_init(kdc);
1666 if (error != 0)
1667 return (error);
1668 keysize = kerneldumpcrypto_dumpkeysize(kdc);
1669 key = keysize > 0 ? kdc->kdc_dumpkey : NULL;
1670 #else
1671 error = 0;
1672 keysize = 0;
1673 key = NULL;
1674 #endif
1675
1676 if (di->dumper_start != NULL) {
1677 error = di->dumper_start(di, key, keysize);
1678 } else {
1679 dumpextent = dtoh64(kdh->dumpextent);
1680 span = SIZEOF_METADATA + dumpextent + 2 * di->blocksize +
1681 keysize;
1682 if (di->mediasize < span) {
1683 if (di->kdcomp == NULL)
1684 return (E2BIG);
1685
1686 /*
1687 * We don't yet know how much space the compressed dump
1688 * will occupy, so try to use the whole swap partition
1689 * (minus the first 64KB) in the hope that the
1690 * compressed dump will fit. If that doesn't turn out to
1691 * be enough, the bounds checking in dump_write()
1692 * will catch us and cause the dump to fail.
1693 */
1694 dumpextent = di->mediasize - span + dumpextent;
1695 kdh->dumpextent = htod64(dumpextent);
1696 }
1697
1698 /*
1699 * The offset at which to begin writing the dump.
1700 */
1701 di->dumpoff = di->mediaoffset + di->mediasize - di->blocksize -
1702 dumpextent;
1703 }
1704 di->origdumpoff = di->dumpoff;
1705 return (error);
1706 }
1707
1708 static int
_dump_append(struct dumperinfo * di,void * virtual,size_t length)1709 _dump_append(struct dumperinfo *di, void *virtual, size_t length)
1710 {
1711 int error;
1712
1713 #ifdef EKCD
1714 if (di->kdcrypto != NULL)
1715 error = dump_encrypted_write(di, virtual, di->dumpoff, length);
1716 else
1717 #endif
1718 error = dump_write(di, virtual, di->dumpoff, length);
1719 if (error == 0)
1720 di->dumpoff += length;
1721 return (error);
1722 }
1723
1724 /*
1725 * Write to the dump device starting at dumpoff. When compression is enabled,
1726 * writes to the device will be performed using a callback that gets invoked
1727 * when the compression stream's output buffer is full.
1728 */
1729 int
dump_append(struct dumperinfo * di,void * virtual,size_t length)1730 dump_append(struct dumperinfo *di, void *virtual, size_t length)
1731 {
1732 void *buf;
1733
1734 if (di->kdcomp != NULL) {
1735 /* Bounce through a buffer to avoid CRC errors. */
1736 if (length > di->maxiosize)
1737 return (EINVAL);
1738 buf = di->kdcomp->kdc_buf;
1739 memmove(buf, virtual, length);
1740 return (compressor_write(di->kdcomp->kdc_stream, buf, length));
1741 }
1742 return (_dump_append(di, virtual, length));
1743 }
1744
1745 /*
1746 * Write to the dump device at the specified offset.
1747 */
1748 int
dump_write(struct dumperinfo * di,void * virtual,off_t offset,size_t length)1749 dump_write(struct dumperinfo *di, void *virtual, off_t offset, size_t length)
1750 {
1751 int error;
1752
1753 error = dump_check_bounds(di, offset, length);
1754 if (error != 0)
1755 return (error);
1756 return (di->dumper(di->priv, virtual, offset, length));
1757 }
1758
1759 /*
1760 * Perform kernel dump finalization: flush the compression stream, if necessary,
1761 * write the leading and trailing kernel dump headers now that we know the true
1762 * length of the dump, and optionally write the encryption key following the
1763 * leading header.
1764 */
1765 int
dump_finish(struct dumperinfo * di,struct kerneldumpheader * kdh)1766 dump_finish(struct dumperinfo *di, struct kerneldumpheader *kdh)
1767 {
1768 int error;
1769
1770 if (di->kdcomp != NULL) {
1771 error = compressor_flush(di->kdcomp->kdc_stream);
1772 if (error == EAGAIN) {
1773 /* We have residual data in di->blockbuf. */
1774 error = _dump_append(di, di->blockbuf, di->blocksize);
1775 if (error == 0)
1776 /* Compensate for _dump_append()'s adjustment. */
1777 di->dumpoff -= di->blocksize - di->kdcomp->kdc_resid;
1778 di->kdcomp->kdc_resid = 0;
1779 }
1780 if (error != 0)
1781 return (error);
1782
1783 /*
1784 * We now know the size of the compressed dump, so update the
1785 * header accordingly and recompute parity.
1786 */
1787 kdh->dumplength = htod64(di->dumpoff - di->origdumpoff);
1788 kdh->parity = 0;
1789 kdh->parity = kerneldump_parity(kdh);
1790
1791 compressor_reset(di->kdcomp->kdc_stream);
1792 }
1793
1794 error = dump_write_headers(di, kdh);
1795 if (error != 0)
1796 return (error);
1797
1798 (void)dump_write(di, NULL, 0, 0);
1799 return (0);
1800 }
1801
1802 void
dump_init_header(const struct dumperinfo * di,struct kerneldumpheader * kdh,const char * magic,uint32_t archver,uint64_t dumplen)1803 dump_init_header(const struct dumperinfo *di, struct kerneldumpheader *kdh,
1804 const char *magic, uint32_t archver, uint64_t dumplen)
1805 {
1806 size_t dstsize;
1807
1808 bzero(kdh, sizeof(*kdh));
1809 strlcpy(kdh->magic, magic, sizeof(kdh->magic));
1810 strlcpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
1811 kdh->version = htod32(KERNELDUMPVERSION);
1812 kdh->architectureversion = htod32(archver);
1813 kdh->dumplength = htod64(dumplen);
1814 kdh->dumpextent = kdh->dumplength;
1815 kdh->dumptime = htod64(time_second);
1816 #ifdef EKCD
1817 kdh->dumpkeysize = htod32(kerneldumpcrypto_dumpkeysize(di->kdcrypto));
1818 #else
1819 kdh->dumpkeysize = 0;
1820 #endif
1821 kdh->blocksize = htod32(di->blocksize);
1822 strlcpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
1823 dstsize = sizeof(kdh->versionstring);
1824 if (strlcpy(kdh->versionstring, version, dstsize) >= dstsize)
1825 kdh->versionstring[dstsize - 2] = '\n';
1826 if (panicstr != NULL)
1827 strlcpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
1828 if (di->kdcomp != NULL)
1829 kdh->compression = di->kdcomp->kdc_format;
1830 kdh->parity = kerneldump_parity(kdh);
1831 }
1832
1833 #ifdef DDB
DB_SHOW_COMMAND_FLAGS(panic,db_show_panic,DB_CMD_MEMSAFE)1834 DB_SHOW_COMMAND_FLAGS(panic, db_show_panic, DB_CMD_MEMSAFE)
1835 {
1836
1837 if (panicstr == NULL)
1838 db_printf("panicstr not set\n");
1839 else
1840 db_printf("panic: %s\n", panicstr);
1841 }
1842 #endif
1843