xref: /freebsd/sys/contrib/openzfs/cmd/zhack.c (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or https://opensource.org/licenses/CDDL-1.0.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
24  * Copyright (c) 2013 Steven Hartland. All rights reserved.
25  */
26 
27 /*
28  * zhack is a debugging tool that can write changes to ZFS pool using libzpool
29  * for testing purposes. Altering pools with zhack is unsupported and may
30  * result in corrupted pools.
31  */
32 
33 #include <zfs_prop.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <ctype.h>
37 #include <sys/stat.h>
38 #include <sys/zfs_context.h>
39 #include <sys/spa.h>
40 #include <sys/spa_impl.h>
41 #include <sys/dmu.h>
42 #include <sys/zap.h>
43 #include <sys/zfs_znode.h>
44 #include <sys/dsl_synctask.h>
45 #include <sys/vdev.h>
46 #include <sys/vdev_impl.h>
47 #include <sys/fs/zfs.h>
48 #include <sys/dmu_objset.h>
49 #include <sys/dsl_pool.h>
50 #include <sys/zio_checksum.h>
51 #include <sys/zio_compress.h>
52 #include <sys/zfeature.h>
53 #include <sys/dmu_tx.h>
54 #include <zfeature_common.h>
55 #include <libzutil.h>
56 
57 static importargs_t g_importargs;
58 static char *g_pool;
59 static boolean_t g_readonly;
60 
61 typedef enum {
62 	ZHACK_REPAIR_OP_UNKNOWN  = 0,
63 	ZHACK_REPAIR_OP_CKSUM    = (1 << 0),
64 	ZHACK_REPAIR_OP_UNDETACH = (1 << 1)
65 } zhack_repair_op_t;
66 
67 static __attribute__((noreturn)) void
68 usage(void)
69 {
70 	(void) fprintf(stderr,
71 	    "Usage: zhack [-c cachefile] [-d dir] <subcommand> <args> ...\n"
72 	    "where <subcommand> <args> is one of the following:\n"
73 	    "\n");
74 
75 	(void) fprintf(stderr,
76 	    "    feature stat <pool>\n"
77 	    "        print information about enabled features\n"
78 	    "    feature enable [-r] [-d desc] <pool> <feature>\n"
79 	    "        add a new enabled feature to the pool\n"
80 	    "        -d <desc> sets the feature's description\n"
81 	    "        -r set read-only compatible flag for feature\n"
82 	    "    feature ref [-md] <pool> <feature>\n"
83 	    "        change the refcount on the given feature\n"
84 	    "        -d decrease instead of increase the refcount\n"
85 	    "        -m add the feature to the label if increasing refcount\n"
86 	    "\n"
87 	    "    <feature> : should be a feature guid\n"
88 	    "\n"
89 	    "    label repair <device>\n"
90 	    "        repair labels of a specified device according to options\n"
91 	    "        which may be combined to do their functions in one call\n"
92 	    "        -c repair corrupted label checksums\n"
93 	    "        -u restore the label on a detached device\n"
94 	    "\n"
95 	    "    <device> : path to vdev\n");
96 	exit(1);
97 }
98 
99 
100 static __attribute__((format(printf, 3, 4))) __attribute__((noreturn)) void
101 fatal(spa_t *spa, const void *tag, const char *fmt, ...)
102 {
103 	va_list ap;
104 
105 	if (spa != NULL) {
106 		spa_close(spa, tag);
107 		(void) spa_export(g_pool, NULL, B_TRUE, B_FALSE);
108 	}
109 
110 	va_start(ap, fmt);
111 	(void) fputs("zhack: ", stderr);
112 	(void) vfprintf(stderr, fmt, ap);
113 	va_end(ap);
114 	(void) fputc('\n', stderr);
115 
116 	exit(1);
117 }
118 
119 static int
120 space_delta_cb(dmu_object_type_t bonustype, const void *data,
121     zfs_file_info_t *zoi)
122 {
123 	(void) data, (void) zoi;
124 
125 	/*
126 	 * Is it a valid type of object to track?
127 	 */
128 	if (bonustype != DMU_OT_ZNODE && bonustype != DMU_OT_SA)
129 		return (ENOENT);
130 	(void) fprintf(stderr, "modifying object that needs user accounting");
131 	abort();
132 }
133 
134 /*
135  * Target is the dataset whose pool we want to open.
136  */
137 static void
138 zhack_import(char *target, boolean_t readonly)
139 {
140 	nvlist_t *config;
141 	nvlist_t *props;
142 	int error;
143 
144 	kernel_init(readonly ? SPA_MODE_READ :
145 	    (SPA_MODE_READ | SPA_MODE_WRITE));
146 
147 	dmu_objset_register_type(DMU_OST_ZFS, space_delta_cb);
148 
149 	g_readonly = readonly;
150 	g_importargs.can_be_active = readonly;
151 	g_pool = strdup(target);
152 
153 	libpc_handle_t lpch = {
154 		.lpc_lib_handle = NULL,
155 		.lpc_ops = &libzpool_config_ops,
156 		.lpc_printerr = B_TRUE
157 	};
158 	error = zpool_find_config(&lpch, target, &config, &g_importargs);
159 	if (error)
160 		fatal(NULL, FTAG, "cannot import '%s'", target);
161 
162 	props = NULL;
163 	if (readonly) {
164 		VERIFY(nvlist_alloc(&props, NV_UNIQUE_NAME, 0) == 0);
165 		VERIFY(nvlist_add_uint64(props,
166 		    zpool_prop_to_name(ZPOOL_PROP_READONLY), 1) == 0);
167 	}
168 
169 	zfeature_checks_disable = B_TRUE;
170 	error = spa_import(target, config, props,
171 	    (readonly ?  ZFS_IMPORT_SKIP_MMP : ZFS_IMPORT_NORMAL));
172 	fnvlist_free(config);
173 	zfeature_checks_disable = B_FALSE;
174 	if (error == EEXIST)
175 		error = 0;
176 
177 	if (error)
178 		fatal(NULL, FTAG, "can't import '%s': %s", target,
179 		    strerror(error));
180 }
181 
182 static void
183 zhack_spa_open(char *target, boolean_t readonly, const void *tag, spa_t **spa)
184 {
185 	int err;
186 
187 	zhack_import(target, readonly);
188 
189 	zfeature_checks_disable = B_TRUE;
190 	err = spa_open(target, spa, tag);
191 	zfeature_checks_disable = B_FALSE;
192 
193 	if (err != 0)
194 		fatal(*spa, FTAG, "cannot open '%s': %s", target,
195 		    strerror(err));
196 	if (spa_version(*spa) < SPA_VERSION_FEATURES) {
197 		fatal(*spa, FTAG, "'%s' has version %d, features not enabled",
198 		    target, (int)spa_version(*spa));
199 	}
200 }
201 
202 static void
203 dump_obj(objset_t *os, uint64_t obj, const char *name)
204 {
205 	zap_cursor_t zc;
206 	zap_attribute_t *za = zap_attribute_long_alloc();
207 
208 	(void) printf("%s_obj:\n", name);
209 
210 	for (zap_cursor_init(&zc, os, obj);
211 	    zap_cursor_retrieve(&zc, za) == 0;
212 	    zap_cursor_advance(&zc)) {
213 		if (za->za_integer_length == 8) {
214 			ASSERT(za->za_num_integers == 1);
215 			(void) printf("\t%s = %llu\n",
216 			    za->za_name, (u_longlong_t)za->za_first_integer);
217 		} else {
218 			ASSERT(za->za_integer_length == 1);
219 			char val[1024];
220 			VERIFY(zap_lookup(os, obj, za->za_name,
221 			    1, sizeof (val), val) == 0);
222 			(void) printf("\t%s = %s\n", za->za_name, val);
223 		}
224 	}
225 	zap_cursor_fini(&zc);
226 	zap_attribute_free(za);
227 }
228 
229 static void
230 dump_mos(spa_t *spa)
231 {
232 	nvlist_t *nv = spa->spa_label_features;
233 	nvpair_t *pair;
234 
235 	(void) printf("label config:\n");
236 	for (pair = nvlist_next_nvpair(nv, NULL);
237 	    pair != NULL;
238 	    pair = nvlist_next_nvpair(nv, pair)) {
239 		(void) printf("\t%s\n", nvpair_name(pair));
240 	}
241 }
242 
243 static void
244 zhack_do_feature_stat(int argc, char **argv)
245 {
246 	spa_t *spa;
247 	objset_t *os;
248 	char *target;
249 
250 	argc--;
251 	argv++;
252 
253 	if (argc < 1) {
254 		(void) fprintf(stderr, "error: missing pool name\n");
255 		usage();
256 	}
257 	target = argv[0];
258 
259 	zhack_spa_open(target, B_TRUE, FTAG, &spa);
260 	os = spa->spa_meta_objset;
261 
262 	dump_obj(os, spa->spa_feat_for_read_obj, "for_read");
263 	dump_obj(os, spa->spa_feat_for_write_obj, "for_write");
264 	dump_obj(os, spa->spa_feat_desc_obj, "descriptions");
265 	if (spa_feature_is_active(spa, SPA_FEATURE_ENABLED_TXG)) {
266 		dump_obj(os, spa->spa_feat_enabled_txg_obj, "enabled_txg");
267 	}
268 	dump_mos(spa);
269 
270 	spa_close(spa, FTAG);
271 }
272 
273 static void
274 zhack_feature_enable_sync(void *arg, dmu_tx_t *tx)
275 {
276 	spa_t *spa = dmu_tx_pool(tx)->dp_spa;
277 	zfeature_info_t *feature = arg;
278 
279 	feature_enable_sync(spa, feature, tx);
280 
281 	spa_history_log_internal(spa, "zhack enable feature", tx,
282 	    "name=%s flags=%u",
283 	    feature->fi_guid, feature->fi_flags);
284 }
285 
286 static void
287 zhack_do_feature_enable(int argc, char **argv)
288 {
289 	int c;
290 	char *desc, *target;
291 	spa_t *spa;
292 	objset_t *mos;
293 	zfeature_info_t feature;
294 	const spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
295 
296 	/*
297 	 * Features are not added to the pool's label until their refcounts
298 	 * are incremented, so fi_mos can just be left as false for now.
299 	 */
300 	desc = NULL;
301 	feature.fi_uname = "zhack";
302 	feature.fi_flags = 0;
303 	feature.fi_depends = nodeps;
304 	feature.fi_feature = SPA_FEATURE_NONE;
305 
306 	optind = 1;
307 	while ((c = getopt(argc, argv, "+rd:")) != -1) {
308 		switch (c) {
309 		case 'r':
310 			feature.fi_flags |= ZFEATURE_FLAG_READONLY_COMPAT;
311 			break;
312 		case 'd':
313 			if (desc != NULL)
314 				free(desc);
315 			desc = strdup(optarg);
316 			break;
317 		default:
318 			usage();
319 			break;
320 		}
321 	}
322 
323 	if (desc == NULL)
324 		desc = strdup("zhack injected");
325 	feature.fi_desc = desc;
326 
327 	argc -= optind;
328 	argv += optind;
329 
330 	if (argc < 2) {
331 		(void) fprintf(stderr, "error: missing feature or pool name\n");
332 		usage();
333 	}
334 	target = argv[0];
335 	feature.fi_guid = argv[1];
336 
337 	if (!zfeature_is_valid_guid(feature.fi_guid))
338 		fatal(NULL, FTAG, "invalid feature guid: %s", feature.fi_guid);
339 
340 	zhack_spa_open(target, B_FALSE, FTAG, &spa);
341 	mos = spa->spa_meta_objset;
342 
343 	if (zfeature_is_supported(feature.fi_guid))
344 		fatal(spa, FTAG, "'%s' is a real feature, will not enable",
345 		    feature.fi_guid);
346 	if (0 == zap_contains(mos, spa->spa_feat_desc_obj, feature.fi_guid))
347 		fatal(spa, FTAG, "feature already enabled: %s",
348 		    feature.fi_guid);
349 
350 	VERIFY0(dsl_sync_task(spa_name(spa), NULL,
351 	    zhack_feature_enable_sync, &feature, 5, ZFS_SPACE_CHECK_NORMAL));
352 
353 	spa_close(spa, FTAG);
354 
355 	free(desc);
356 }
357 
358 static void
359 feature_incr_sync(void *arg, dmu_tx_t *tx)
360 {
361 	spa_t *spa = dmu_tx_pool(tx)->dp_spa;
362 	zfeature_info_t *feature = arg;
363 	uint64_t refcount;
364 
365 	VERIFY0(feature_get_refcount_from_disk(spa, feature, &refcount));
366 	feature_sync(spa, feature, refcount + 1, tx);
367 	spa_history_log_internal(spa, "zhack feature incr", tx,
368 	    "name=%s", feature->fi_guid);
369 }
370 
371 static void
372 feature_decr_sync(void *arg, dmu_tx_t *tx)
373 {
374 	spa_t *spa = dmu_tx_pool(tx)->dp_spa;
375 	zfeature_info_t *feature = arg;
376 	uint64_t refcount;
377 
378 	VERIFY0(feature_get_refcount_from_disk(spa, feature, &refcount));
379 	feature_sync(spa, feature, refcount - 1, tx);
380 	spa_history_log_internal(spa, "zhack feature decr", tx,
381 	    "name=%s", feature->fi_guid);
382 }
383 
384 static void
385 zhack_do_feature_ref(int argc, char **argv)
386 {
387 	int c;
388 	char *target;
389 	boolean_t decr = B_FALSE;
390 	spa_t *spa;
391 	objset_t *mos;
392 	zfeature_info_t feature;
393 	const spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
394 
395 	/*
396 	 * fi_desc does not matter here because it was written to disk
397 	 * when the feature was enabled, but we need to properly set the
398 	 * feature for read or write based on the information we read off
399 	 * disk later.
400 	 */
401 	feature.fi_uname = "zhack";
402 	feature.fi_flags = 0;
403 	feature.fi_desc = NULL;
404 	feature.fi_depends = nodeps;
405 	feature.fi_feature = SPA_FEATURE_NONE;
406 
407 	optind = 1;
408 	while ((c = getopt(argc, argv, "+md")) != -1) {
409 		switch (c) {
410 		case 'm':
411 			feature.fi_flags |= ZFEATURE_FLAG_MOS;
412 			break;
413 		case 'd':
414 			decr = B_TRUE;
415 			break;
416 		default:
417 			usage();
418 			break;
419 		}
420 	}
421 	argc -= optind;
422 	argv += optind;
423 
424 	if (argc < 2) {
425 		(void) fprintf(stderr, "error: missing feature or pool name\n");
426 		usage();
427 	}
428 	target = argv[0];
429 	feature.fi_guid = argv[1];
430 
431 	if (!zfeature_is_valid_guid(feature.fi_guid))
432 		fatal(NULL, FTAG, "invalid feature guid: %s", feature.fi_guid);
433 
434 	zhack_spa_open(target, B_FALSE, FTAG, &spa);
435 	mos = spa->spa_meta_objset;
436 
437 	if (zfeature_is_supported(feature.fi_guid)) {
438 		fatal(spa, FTAG,
439 		    "'%s' is a real feature, will not change refcount",
440 		    feature.fi_guid);
441 	}
442 
443 	if (0 == zap_contains(mos, spa->spa_feat_for_read_obj,
444 	    feature.fi_guid)) {
445 		feature.fi_flags &= ~ZFEATURE_FLAG_READONLY_COMPAT;
446 	} else if (0 == zap_contains(mos, spa->spa_feat_for_write_obj,
447 	    feature.fi_guid)) {
448 		feature.fi_flags |= ZFEATURE_FLAG_READONLY_COMPAT;
449 	} else {
450 		fatal(spa, FTAG, "feature is not enabled: %s", feature.fi_guid);
451 	}
452 
453 	if (decr) {
454 		uint64_t count;
455 		if (feature_get_refcount_from_disk(spa, &feature,
456 		    &count) == 0 && count == 0) {
457 			fatal(spa, FTAG, "feature refcount already 0: %s",
458 			    feature.fi_guid);
459 		}
460 	}
461 
462 	VERIFY0(dsl_sync_task(spa_name(spa), NULL,
463 	    decr ? feature_decr_sync : feature_incr_sync, &feature,
464 	    5, ZFS_SPACE_CHECK_NORMAL));
465 
466 	spa_close(spa, FTAG);
467 }
468 
469 static int
470 zhack_do_feature(int argc, char **argv)
471 {
472 	char *subcommand;
473 
474 	argc--;
475 	argv++;
476 	if (argc == 0) {
477 		(void) fprintf(stderr,
478 		    "error: no feature operation specified\n");
479 		usage();
480 	}
481 
482 	subcommand = argv[0];
483 	if (strcmp(subcommand, "stat") == 0) {
484 		zhack_do_feature_stat(argc, argv);
485 	} else if (strcmp(subcommand, "enable") == 0) {
486 		zhack_do_feature_enable(argc, argv);
487 	} else if (strcmp(subcommand, "ref") == 0) {
488 		zhack_do_feature_ref(argc, argv);
489 	} else {
490 		(void) fprintf(stderr, "error: unknown subcommand: %s\n",
491 		    subcommand);
492 		usage();
493 	}
494 
495 	return (0);
496 }
497 
498 #define	ASHIFT_UBERBLOCK_SHIFT(ashift)	\
499 	MIN(MAX(ashift, UBERBLOCK_SHIFT), \
500 	MAX_UBERBLOCK_SHIFT)
501 #define	ASHIFT_UBERBLOCK_SIZE(ashift) \
502 	(1ULL << ASHIFT_UBERBLOCK_SHIFT(ashift))
503 
504 #define	REPAIR_LABEL_STATUS_CKSUM (1 << 0)
505 #define	REPAIR_LABEL_STATUS_UB    (1 << 1)
506 
507 static int
508 zhack_repair_read_label(const int fd, vdev_label_t *vl,
509     const uint64_t label_offset, const int l)
510 {
511 	const int err = pread64(fd, vl, sizeof (vdev_label_t), label_offset);
512 
513 	if (err == -1) {
514 		(void) fprintf(stderr,
515 		    "error: cannot read label %d: %s\n",
516 		    l, strerror(errno));
517 		return (err);
518 	} else if (err != sizeof (vdev_label_t)) {
519 		(void) fprintf(stderr,
520 		    "error: bad label %d read size\n", l);
521 		return (err);
522 	}
523 
524 	return (0);
525 }
526 
527 static void
528 zhack_repair_calc_cksum(const int byteswap, void *data, const uint64_t offset,
529     const uint64_t abdsize, zio_eck_t *eck, zio_cksum_t *cksum)
530 {
531 	zio_cksum_t verifier;
532 	zio_cksum_t current_cksum;
533 	zio_checksum_info_t *ci;
534 	abd_t *abd;
535 
536 	ZIO_SET_CHECKSUM(&verifier, offset, 0, 0, 0);
537 
538 	if (byteswap)
539 		byteswap_uint64_array(&verifier, sizeof (zio_cksum_t));
540 
541 	current_cksum = eck->zec_cksum;
542 	eck->zec_cksum = verifier;
543 
544 	ci = &zio_checksum_table[ZIO_CHECKSUM_LABEL];
545 	abd = abd_get_from_buf(data, abdsize);
546 	ci->ci_func[byteswap](abd, abdsize, NULL, cksum);
547 	abd_free(abd);
548 
549 	eck->zec_cksum = current_cksum;
550 }
551 
552 static int
553 zhack_repair_check_label(uberblock_t *ub, const int l, const char **cfg_keys,
554     const size_t cfg_keys_len, nvlist_t *cfg, nvlist_t *vdev_tree_cfg,
555     uint64_t *ashift)
556 {
557 	int err;
558 
559 	if (ub->ub_txg != 0) {
560 		(void) fprintf(stderr,
561 		    "error: label %d: UB TXG of 0 expected, but got %"
562 		    PRIu64 "\n",
563 		    l, ub->ub_txg);
564 		(void) fprintf(stderr, "It would appear the device was not "
565 		    "properly removed.\n");
566 		return (1);
567 	}
568 
569 	for (int i = 0; i < cfg_keys_len; i++) {
570 		uint64_t val;
571 		err = nvlist_lookup_uint64(cfg, cfg_keys[i], &val);
572 		if (err) {
573 			(void) fprintf(stderr,
574 			    "error: label %d, %d: "
575 			    "cannot find nvlist key %s\n",
576 			    l, i, cfg_keys[i]);
577 			return (err);
578 		}
579 	}
580 
581 	err = nvlist_lookup_nvlist(cfg,
582 	    ZPOOL_CONFIG_VDEV_TREE, &vdev_tree_cfg);
583 	if (err) {
584 		(void) fprintf(stderr,
585 		    "error: label %d: cannot find nvlist key %s\n",
586 		    l, ZPOOL_CONFIG_VDEV_TREE);
587 		return (err);
588 	}
589 
590 	err = nvlist_lookup_uint64(vdev_tree_cfg,
591 	    ZPOOL_CONFIG_ASHIFT, ashift);
592 	if (err) {
593 		(void) fprintf(stderr,
594 		    "error: label %d: cannot find nvlist key %s\n",
595 		    l, ZPOOL_CONFIG_ASHIFT);
596 		return (err);
597 	}
598 
599 	if (*ashift == 0) {
600 		(void) fprintf(stderr,
601 		    "error: label %d: nvlist key %s is zero\n",
602 		    l, ZPOOL_CONFIG_ASHIFT);
603 		return (err);
604 	}
605 
606 	return (0);
607 }
608 
609 static int
610 zhack_repair_undetach(uberblock_t *ub, nvlist_t *cfg, const int l)
611 {
612 	/*
613 	 * Uberblock root block pointer has valid birth TXG.
614 	 * Copying it to the label NVlist
615 	 */
616 	if (BP_GET_LOGICAL_BIRTH(&ub->ub_rootbp) != 0) {
617 		const uint64_t txg = BP_GET_LOGICAL_BIRTH(&ub->ub_rootbp);
618 		ub->ub_txg = txg;
619 
620 		if (nvlist_remove_all(cfg, ZPOOL_CONFIG_CREATE_TXG) != 0) {
621 			(void) fprintf(stderr,
622 			    "error: label %d: "
623 			    "Failed to remove pool creation TXG\n",
624 			    l);
625 			return (1);
626 		}
627 
628 		if (nvlist_remove_all(cfg, ZPOOL_CONFIG_POOL_TXG) != 0) {
629 			(void) fprintf(stderr,
630 			    "error: label %d: Failed to remove pool TXG to "
631 			    "be replaced.\n",
632 			    l);
633 			return (1);
634 		}
635 
636 		if (nvlist_add_uint64(cfg, ZPOOL_CONFIG_POOL_TXG, txg) != 0) {
637 			(void) fprintf(stderr,
638 			    "error: label %d: "
639 			    "Failed to add pool TXG of %" PRIu64 "\n",
640 			    l, txg);
641 			return (1);
642 		}
643 	}
644 
645 	return (0);
646 }
647 
648 static boolean_t
649 zhack_repair_write_label(const int l, const int fd, const int byteswap,
650     void *data, zio_eck_t *eck, const uint64_t offset, const uint64_t abdsize)
651 {
652 	zio_cksum_t actual_cksum;
653 	zhack_repair_calc_cksum(byteswap, data, offset, abdsize, eck,
654 	    &actual_cksum);
655 	zio_cksum_t expected_cksum = eck->zec_cksum;
656 	ssize_t err;
657 
658 	if (ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum))
659 		return (B_FALSE);
660 
661 	eck->zec_cksum = actual_cksum;
662 
663 	err = pwrite64(fd, data, abdsize, offset);
664 	if (err == -1) {
665 		(void) fprintf(stderr, "error: cannot write label %d: %s\n",
666 		    l, strerror(errno));
667 		return (B_FALSE);
668 	} else if (err != abdsize) {
669 		(void) fprintf(stderr, "error: bad write size label %d\n", l);
670 		return (B_FALSE);
671 	} else {
672 		(void) fprintf(stderr,
673 		    "label %d: wrote %" PRIu64 " bytes at offset %" PRIu64 "\n",
674 		    l, abdsize, offset);
675 	}
676 
677 	return (B_TRUE);
678 }
679 
680 static void
681 zhack_repair_write_uberblock(vdev_label_t *vl, const int l,
682     const uint64_t ashift, const int fd, const int byteswap,
683     const uint64_t label_offset, uint32_t *labels_repaired)
684 {
685 	void *ub_data =
686 	    (char *)vl + offsetof(vdev_label_t, vl_uberblock);
687 	zio_eck_t *ub_eck =
688 	    (zio_eck_t *)
689 	    ((char *)(ub_data) + (ASHIFT_UBERBLOCK_SIZE(ashift))) - 1;
690 
691 	if (ub_eck->zec_magic != 0) {
692 		(void) fprintf(stderr,
693 		    "error: label %d: "
694 		    "Expected Uberblock checksum magic number to "
695 		    "be 0, but got %" PRIu64 "\n",
696 		    l, ub_eck->zec_magic);
697 		(void) fprintf(stderr, "It would appear there's already "
698 		    "a checksum for the uberblock.\n");
699 		return;
700 	}
701 
702 
703 	ub_eck->zec_magic = byteswap ? BSWAP_64(ZEC_MAGIC) : ZEC_MAGIC;
704 
705 	if (zhack_repair_write_label(l, fd, byteswap,
706 	    ub_data, ub_eck,
707 	    label_offset + offsetof(vdev_label_t, vl_uberblock),
708 	    ASHIFT_UBERBLOCK_SIZE(ashift)))
709 			labels_repaired[l] |= REPAIR_LABEL_STATUS_UB;
710 }
711 
712 static void
713 zhack_repair_print_cksum(FILE *stream, const zio_cksum_t *cksum)
714 {
715 	(void) fprintf(stream,
716 	    "%016llx:%016llx:%016llx:%016llx",
717 	    (u_longlong_t)cksum->zc_word[0],
718 	    (u_longlong_t)cksum->zc_word[1],
719 	    (u_longlong_t)cksum->zc_word[2],
720 	    (u_longlong_t)cksum->zc_word[3]);
721 }
722 
723 static int
724 zhack_repair_test_cksum(const int byteswap, void *vdev_data,
725     zio_eck_t *vdev_eck, const uint64_t vdev_phys_offset, const int l)
726 {
727 	const zio_cksum_t expected_cksum = vdev_eck->zec_cksum;
728 	zio_cksum_t actual_cksum;
729 	zhack_repair_calc_cksum(byteswap, vdev_data, vdev_phys_offset,
730 	    VDEV_PHYS_SIZE, vdev_eck, &actual_cksum);
731 	const uint64_t expected_magic = byteswap ?
732 	    BSWAP_64(ZEC_MAGIC) : ZEC_MAGIC;
733 	const uint64_t actual_magic = vdev_eck->zec_magic;
734 	int err = 0;
735 	if (actual_magic != expected_magic) {
736 		(void) fprintf(stderr, "error: label %d: "
737 		    "Expected "
738 		    "the nvlist checksum magic number to not be %"
739 		    PRIu64 " not %" PRIu64 "\n",
740 		    l, expected_magic, actual_magic);
741 		err = ECKSUM;
742 	}
743 	if (!ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum)) {
744 		(void) fprintf(stderr, "error: label %d: "
745 		    "Expected the nvlist checksum to be ", l);
746 		(void) zhack_repair_print_cksum(stderr,
747 		    &expected_cksum);
748 		(void) fprintf(stderr, " not ");
749 		zhack_repair_print_cksum(stderr, &actual_cksum);
750 		(void) fprintf(stderr, "\n");
751 		err = ECKSUM;
752 	}
753 	return (err);
754 }
755 
756 static void
757 zhack_repair_one_label(const zhack_repair_op_t op, const int fd,
758     vdev_label_t *vl, const uint64_t label_offset, const int l,
759     uint32_t *labels_repaired)
760 {
761 	ssize_t err;
762 	uberblock_t *ub = (uberblock_t *)vl->vl_uberblock;
763 	void *vdev_data =
764 	    (char *)vl + offsetof(vdev_label_t, vl_vdev_phys);
765 	zio_eck_t *vdev_eck =
766 	    (zio_eck_t *)((char *)(vdev_data) + VDEV_PHYS_SIZE) - 1;
767 	const uint64_t vdev_phys_offset =
768 	    label_offset + offsetof(vdev_label_t, vl_vdev_phys);
769 	const char *cfg_keys[] = { ZPOOL_CONFIG_VERSION,
770 	    ZPOOL_CONFIG_POOL_STATE, ZPOOL_CONFIG_GUID };
771 	nvlist_t *cfg;
772 	nvlist_t *vdev_tree_cfg = NULL;
773 	uint64_t ashift;
774 	int byteswap;
775 
776 	err = zhack_repair_read_label(fd, vl, label_offset, l);
777 	if (err)
778 		return;
779 
780 	if (vdev_eck->zec_magic == 0) {
781 		(void) fprintf(stderr, "error: label %d: "
782 		    "Expected the nvlist checksum magic number to not be zero"
783 		    "\n",
784 		    l);
785 		(void) fprintf(stderr, "There should already be a checksum "
786 		    "for the label.\n");
787 		return;
788 	}
789 
790 	byteswap =
791 	    (vdev_eck->zec_magic == BSWAP_64((uint64_t)ZEC_MAGIC));
792 
793 	if (byteswap) {
794 		byteswap_uint64_array(&vdev_eck->zec_cksum,
795 		    sizeof (zio_cksum_t));
796 		vdev_eck->zec_magic = BSWAP_64(vdev_eck->zec_magic);
797 	}
798 
799 	if ((op & ZHACK_REPAIR_OP_CKSUM) == 0 &&
800 	    zhack_repair_test_cksum(byteswap, vdev_data, vdev_eck,
801 	    vdev_phys_offset, l) != 0) {
802 		(void) fprintf(stderr, "It would appear checksums are "
803 		    "corrupted. Try zhack repair label -c <device>\n");
804 		return;
805 	}
806 
807 	err = nvlist_unpack(vl->vl_vdev_phys.vp_nvlist,
808 	    VDEV_PHYS_SIZE - sizeof (zio_eck_t), &cfg, 0);
809 	if (err) {
810 		(void) fprintf(stderr,
811 		    "error: cannot unpack nvlist label %d\n", l);
812 		return;
813 	}
814 
815 	err = zhack_repair_check_label(ub,
816 	    l, cfg_keys, ARRAY_SIZE(cfg_keys), cfg, vdev_tree_cfg, &ashift);
817 	if (err)
818 		return;
819 
820 	if ((op & ZHACK_REPAIR_OP_UNDETACH) != 0) {
821 		char *buf;
822 		size_t buflen;
823 
824 		err = zhack_repair_undetach(ub, cfg, l);
825 		if (err)
826 			return;
827 
828 		buf = vl->vl_vdev_phys.vp_nvlist;
829 		buflen = VDEV_PHYS_SIZE - sizeof (zio_eck_t);
830 		if (nvlist_pack(cfg, &buf, &buflen, NV_ENCODE_XDR, 0) != 0) {
831 			(void) fprintf(stderr,
832 			    "error: label %d: Failed to pack nvlist\n", l);
833 			return;
834 		}
835 
836 		zhack_repair_write_uberblock(vl,
837 		    l, ashift, fd, byteswap, label_offset, labels_repaired);
838 	}
839 
840 	if (zhack_repair_write_label(l, fd, byteswap, vdev_data, vdev_eck,
841 	    vdev_phys_offset, VDEV_PHYS_SIZE))
842 			labels_repaired[l] |= REPAIR_LABEL_STATUS_CKSUM;
843 
844 	fsync(fd);
845 }
846 
847 static const char *
848 zhack_repair_label_status(const uint32_t label_status,
849     const uint32_t to_check)
850 {
851 	return ((label_status & to_check) != 0 ? "repaired" : "skipped");
852 }
853 
854 static int
855 zhack_label_repair(const zhack_repair_op_t op, const int argc, char **argv)
856 {
857 	uint32_t labels_repaired[VDEV_LABELS] = {0};
858 	vdev_label_t labels[VDEV_LABELS] = {{{0}}};
859 	struct stat64 st;
860 	int fd;
861 	off_t filesize;
862 	uint32_t repaired = 0;
863 
864 	abd_init();
865 
866 	if (argc < 1) {
867 		(void) fprintf(stderr, "error: missing device\n");
868 		usage();
869 	}
870 
871 	if ((fd = open(argv[0], O_RDWR)) == -1)
872 		fatal(NULL, FTAG, "cannot open '%s': %s", argv[0],
873 		    strerror(errno));
874 
875 	if (fstat64_blk(fd, &st) != 0)
876 		fatal(NULL, FTAG, "cannot stat '%s': %s", argv[0],
877 		    strerror(errno));
878 
879 	filesize = st.st_size;
880 	(void) fprintf(stderr, "Calculated filesize to be %jd\n",
881 	    (intmax_t)filesize);
882 
883 	if (filesize % sizeof (vdev_label_t) != 0)
884 		filesize =
885 		    (filesize / sizeof (vdev_label_t)) * sizeof (vdev_label_t);
886 
887 	for (int l = 0; l < VDEV_LABELS; l++) {
888 		zhack_repair_one_label(op, fd, &labels[l],
889 		    vdev_label_offset(filesize, l, 0), l, labels_repaired);
890 	}
891 
892 	close(fd);
893 
894 	abd_fini();
895 
896 	for (int l = 0; l < VDEV_LABELS; l++) {
897 		const uint32_t lr = labels_repaired[l];
898 		(void) printf("label %d: ", l);
899 		(void) printf("uberblock: %s ",
900 		    zhack_repair_label_status(lr, REPAIR_LABEL_STATUS_UB));
901 		(void) printf("checksum: %s\n",
902 		    zhack_repair_label_status(lr, REPAIR_LABEL_STATUS_CKSUM));
903 		repaired |= lr;
904 	}
905 
906 	if (repaired > 0)
907 		return (0);
908 
909 	return (1);
910 }
911 
912 static int
913 zhack_do_label_repair(int argc, char **argv)
914 {
915 	zhack_repair_op_t op = ZHACK_REPAIR_OP_UNKNOWN;
916 	int c;
917 
918 	optind = 1;
919 	while ((c = getopt(argc, argv, "+cu")) != -1) {
920 		switch (c) {
921 		case 'c':
922 			op |= ZHACK_REPAIR_OP_CKSUM;
923 			break;
924 		case 'u':
925 			op |= ZHACK_REPAIR_OP_UNDETACH;
926 			break;
927 		default:
928 			usage();
929 			break;
930 		}
931 	}
932 
933 	argc -= optind;
934 	argv += optind;
935 
936 	if (op == ZHACK_REPAIR_OP_UNKNOWN)
937 		op = ZHACK_REPAIR_OP_CKSUM;
938 
939 	return (zhack_label_repair(op, argc, argv));
940 }
941 
942 static int
943 zhack_do_label(int argc, char **argv)
944 {
945 	char *subcommand;
946 	int err;
947 
948 	argc--;
949 	argv++;
950 	if (argc == 0) {
951 		(void) fprintf(stderr,
952 		    "error: no label operation specified\n");
953 		usage();
954 	}
955 
956 	subcommand = argv[0];
957 	if (strcmp(subcommand, "repair") == 0) {
958 		err = zhack_do_label_repair(argc, argv);
959 	} else {
960 		(void) fprintf(stderr, "error: unknown subcommand: %s\n",
961 		    subcommand);
962 		usage();
963 	}
964 
965 	return (err);
966 }
967 
968 #define	MAX_NUM_PATHS 1024
969 
970 int
971 main(int argc, char **argv)
972 {
973 	char *path[MAX_NUM_PATHS];
974 	const char *subcommand;
975 	int rv = 0;
976 	int c;
977 
978 	g_importargs.path = path;
979 
980 	dprintf_setup(&argc, argv);
981 	zfs_prop_init();
982 
983 	while ((c = getopt(argc, argv, "+c:d:")) != -1) {
984 		switch (c) {
985 		case 'c':
986 			g_importargs.cachefile = optarg;
987 			break;
988 		case 'd':
989 			assert(g_importargs.paths < MAX_NUM_PATHS);
990 			g_importargs.path[g_importargs.paths++] = optarg;
991 			break;
992 		default:
993 			usage();
994 			break;
995 		}
996 	}
997 
998 	argc -= optind;
999 	argv += optind;
1000 	optind = 1;
1001 
1002 	if (argc == 0) {
1003 		(void) fprintf(stderr, "error: no command specified\n");
1004 		usage();
1005 	}
1006 
1007 	subcommand = argv[0];
1008 
1009 	if (strcmp(subcommand, "feature") == 0) {
1010 		rv = zhack_do_feature(argc, argv);
1011 	} else if (strcmp(subcommand, "label") == 0) {
1012 		return (zhack_do_label(argc, argv));
1013 	} else {
1014 		(void) fprintf(stderr, "error: unknown subcommand: %s\n",
1015 		    subcommand);
1016 		usage();
1017 	}
1018 
1019 	if (!g_readonly && spa_export(g_pool, NULL, B_TRUE, B_FALSE) != 0) {
1020 		fatal(NULL, FTAG, "pool export failed; "
1021 		    "changes may not be committed to disk\n");
1022 	}
1023 
1024 	kernel_fini();
1025 
1026 	return (rv);
1027 }
1028