xref: /freebsd/sys/contrib/openzfs/cmd/zhack.c (revision 61145dc2b94f12f6a47344fb9aac702321880e43)
1 // SPDX-License-Identifier: CDDL-1.0
2 /*
3  * CDDL HEADER START
4  *
5  * The contents of this file are subject to the terms of the
6  * Common Development and Distribution License (the "License").
7  * You may not use this file except in compliance with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or https://opensource.org/licenses/CDDL-1.0.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
25  * Copyright (c) 2013 Steven Hartland. All rights reserved.
26  */
27 
28 /*
29  * zhack is a debugging tool that can write changes to ZFS pool using libzpool
30  * for testing purposes. Altering pools with zhack is unsupported and may
31  * result in corrupted pools.
32  */
33 
34 #include <zfs_prop.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <ctype.h>
38 #include <sys/stat.h>
39 #include <sys/zfs_context.h>
40 #include <sys/spa.h>
41 #include <sys/spa_impl.h>
42 #include <sys/dmu.h>
43 #include <sys/zap.h>
44 #include <sys/zfs_znode.h>
45 #include <sys/dsl_synctask.h>
46 #include <sys/vdev.h>
47 #include <sys/vdev_impl.h>
48 #include <sys/fs/zfs.h>
49 #include <sys/dmu_objset.h>
50 #include <sys/dsl_pool.h>
51 #include <sys/zio_checksum.h>
52 #include <sys/zio_compress.h>
53 #include <sys/zfeature.h>
54 #include <sys/dmu_tx.h>
55 #include <zfeature_common.h>
56 #include <libzutil.h>
57 
58 static importargs_t g_importargs;
59 static char *g_pool;
60 static boolean_t g_readonly;
61 
62 typedef enum {
63 	ZHACK_REPAIR_OP_UNKNOWN  = 0,
64 	ZHACK_REPAIR_OP_CKSUM    = (1 << 0),
65 	ZHACK_REPAIR_OP_UNDETACH = (1 << 1)
66 } zhack_repair_op_t;
67 
68 static __attribute__((noreturn)) void
usage(void)69 usage(void)
70 {
71 	(void) fprintf(stderr,
72 	    "Usage: zhack [-c cachefile] [-d dir] <subcommand> <args> ...\n"
73 	    "where <subcommand> <args> is one of the following:\n"
74 	    "\n");
75 
76 	(void) fprintf(stderr,
77 	    "    feature stat <pool>\n"
78 	    "        print information about enabled features\n"
79 	    "    feature enable [-r] [-d desc] <pool> <feature>\n"
80 	    "        add a new enabled feature to the pool\n"
81 	    "        -d <desc> sets the feature's description\n"
82 	    "        -r set read-only compatible flag for feature\n"
83 	    "    feature ref [-md] <pool> <feature>\n"
84 	    "        change the refcount on the given feature\n"
85 	    "        -d decrease instead of increase the refcount\n"
86 	    "        -m add the feature to the label if increasing refcount\n"
87 	    "\n"
88 	    "    <feature> : should be a feature guid\n"
89 	    "\n"
90 	    "    label repair <device>\n"
91 	    "        repair labels of a specified device according to options\n"
92 	    "        which may be combined to do their functions in one call\n"
93 	    "        -c repair corrupted label checksums\n"
94 	    "        -u restore the label on a detached device\n"
95 	    "\n"
96 	    "    <device> : path to vdev\n");
97 	exit(1);
98 }
99 
100 
101 static __attribute__((format(printf, 3, 4))) __attribute__((noreturn)) void
fatal(spa_t * spa,const void * tag,const char * fmt,...)102 fatal(spa_t *spa, const void *tag, const char *fmt, ...)
103 {
104 	va_list ap;
105 
106 	if (spa != NULL) {
107 		spa_close(spa, tag);
108 		(void) spa_export(g_pool, NULL, B_TRUE, B_FALSE);
109 	}
110 
111 	va_start(ap, fmt);
112 	(void) fputs("zhack: ", stderr);
113 	(void) vfprintf(stderr, fmt, ap);
114 	va_end(ap);
115 	(void) fputc('\n', stderr);
116 
117 	exit(1);
118 }
119 
120 static int
space_delta_cb(dmu_object_type_t bonustype,const void * data,zfs_file_info_t * zoi)121 space_delta_cb(dmu_object_type_t bonustype, const void *data,
122     zfs_file_info_t *zoi)
123 {
124 	(void) data, (void) zoi;
125 
126 	/*
127 	 * Is it a valid type of object to track?
128 	 */
129 	if (bonustype != DMU_OT_ZNODE && bonustype != DMU_OT_SA)
130 		return (ENOENT);
131 	(void) fprintf(stderr, "modifying object that needs user accounting");
132 	abort();
133 }
134 
135 /*
136  * Target is the dataset whose pool we want to open.
137  */
138 static void
zhack_import(char * target,boolean_t readonly)139 zhack_import(char *target, boolean_t readonly)
140 {
141 	nvlist_t *config;
142 	nvlist_t *props;
143 	int error;
144 
145 	kernel_init(readonly ? SPA_MODE_READ :
146 	    (SPA_MODE_READ | SPA_MODE_WRITE));
147 
148 	dmu_objset_register_type(DMU_OST_ZFS, space_delta_cb);
149 
150 	g_readonly = readonly;
151 	g_importargs.can_be_active = readonly;
152 	g_pool = strdup(target);
153 
154 	libpc_handle_t lpch = {
155 		.lpc_lib_handle = NULL,
156 		.lpc_ops = &libzpool_config_ops,
157 		.lpc_printerr = B_TRUE
158 	};
159 	error = zpool_find_config(&lpch, target, &config, &g_importargs);
160 	if (error)
161 		fatal(NULL, FTAG, "cannot import '%s'", target);
162 
163 	props = NULL;
164 	if (readonly) {
165 		VERIFY(nvlist_alloc(&props, NV_UNIQUE_NAME, 0) == 0);
166 		VERIFY(nvlist_add_uint64(props,
167 		    zpool_prop_to_name(ZPOOL_PROP_READONLY), 1) == 0);
168 	}
169 
170 	zfeature_checks_disable = B_TRUE;
171 	error = spa_import(target, config, props,
172 	    (readonly ?  ZFS_IMPORT_SKIP_MMP : ZFS_IMPORT_NORMAL));
173 	fnvlist_free(config);
174 	zfeature_checks_disable = B_FALSE;
175 	if (error == EEXIST)
176 		error = 0;
177 
178 	if (error)
179 		fatal(NULL, FTAG, "can't import '%s': %s", target,
180 		    strerror(error));
181 }
182 
183 static void
zhack_spa_open(char * target,boolean_t readonly,const void * tag,spa_t ** spa)184 zhack_spa_open(char *target, boolean_t readonly, const void *tag, spa_t **spa)
185 {
186 	int err;
187 
188 	zhack_import(target, readonly);
189 
190 	zfeature_checks_disable = B_TRUE;
191 	err = spa_open(target, spa, tag);
192 	zfeature_checks_disable = B_FALSE;
193 
194 	if (err != 0)
195 		fatal(*spa, FTAG, "cannot open '%s': %s", target,
196 		    strerror(err));
197 	if (spa_version(*spa) < SPA_VERSION_FEATURES) {
198 		fatal(*spa, FTAG, "'%s' has version %d, features not enabled",
199 		    target, (int)spa_version(*spa));
200 	}
201 }
202 
203 static void
dump_obj(objset_t * os,uint64_t obj,const char * name)204 dump_obj(objset_t *os, uint64_t obj, const char *name)
205 {
206 	zap_cursor_t zc;
207 	zap_attribute_t *za = zap_attribute_long_alloc();
208 
209 	(void) printf("%s_obj:\n", name);
210 
211 	for (zap_cursor_init(&zc, os, obj);
212 	    zap_cursor_retrieve(&zc, za) == 0;
213 	    zap_cursor_advance(&zc)) {
214 		if (za->za_integer_length == 8) {
215 			ASSERT(za->za_num_integers == 1);
216 			(void) printf("\t%s = %llu\n",
217 			    za->za_name, (u_longlong_t)za->za_first_integer);
218 		} else {
219 			ASSERT(za->za_integer_length == 1);
220 			char val[1024];
221 			VERIFY(zap_lookup(os, obj, za->za_name,
222 			    1, sizeof (val), val) == 0);
223 			(void) printf("\t%s = %s\n", za->za_name, val);
224 		}
225 	}
226 	zap_cursor_fini(&zc);
227 	zap_attribute_free(za);
228 }
229 
230 static void
dump_mos(spa_t * spa)231 dump_mos(spa_t *spa)
232 {
233 	nvlist_t *nv = spa->spa_label_features;
234 	nvpair_t *pair;
235 
236 	(void) printf("label config:\n");
237 	for (pair = nvlist_next_nvpair(nv, NULL);
238 	    pair != NULL;
239 	    pair = nvlist_next_nvpair(nv, pair)) {
240 		(void) printf("\t%s\n", nvpair_name(pair));
241 	}
242 }
243 
244 static void
zhack_do_feature_stat(int argc,char ** argv)245 zhack_do_feature_stat(int argc, char **argv)
246 {
247 	spa_t *spa;
248 	objset_t *os;
249 	char *target;
250 
251 	argc--;
252 	argv++;
253 
254 	if (argc < 1) {
255 		(void) fprintf(stderr, "error: missing pool name\n");
256 		usage();
257 	}
258 	target = argv[0];
259 
260 	zhack_spa_open(target, B_TRUE, FTAG, &spa);
261 	os = spa->spa_meta_objset;
262 
263 	dump_obj(os, spa->spa_feat_for_read_obj, "for_read");
264 	dump_obj(os, spa->spa_feat_for_write_obj, "for_write");
265 	dump_obj(os, spa->spa_feat_desc_obj, "descriptions");
266 	if (spa_feature_is_active(spa, SPA_FEATURE_ENABLED_TXG)) {
267 		dump_obj(os, spa->spa_feat_enabled_txg_obj, "enabled_txg");
268 	}
269 	dump_mos(spa);
270 
271 	spa_close(spa, FTAG);
272 }
273 
274 static void
zhack_feature_enable_sync(void * arg,dmu_tx_t * tx)275 zhack_feature_enable_sync(void *arg, dmu_tx_t *tx)
276 {
277 	spa_t *spa = dmu_tx_pool(tx)->dp_spa;
278 	zfeature_info_t *feature = arg;
279 
280 	feature_enable_sync(spa, feature, tx);
281 
282 	spa_history_log_internal(spa, "zhack enable feature", tx,
283 	    "name=%s flags=%u",
284 	    feature->fi_guid, feature->fi_flags);
285 }
286 
287 static void
zhack_do_feature_enable(int argc,char ** argv)288 zhack_do_feature_enable(int argc, char **argv)
289 {
290 	int c;
291 	char *desc, *target;
292 	spa_t *spa;
293 	objset_t *mos;
294 	zfeature_info_t feature;
295 	const spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
296 
297 	/*
298 	 * Features are not added to the pool's label until their refcounts
299 	 * are incremented, so fi_mos can just be left as false for now.
300 	 */
301 	desc = NULL;
302 	feature.fi_uname = "zhack";
303 	feature.fi_flags = 0;
304 	feature.fi_depends = nodeps;
305 	feature.fi_feature = SPA_FEATURE_NONE;
306 
307 	optind = 1;
308 	while ((c = getopt(argc, argv, "+rd:")) != -1) {
309 		switch (c) {
310 		case 'r':
311 			feature.fi_flags |= ZFEATURE_FLAG_READONLY_COMPAT;
312 			break;
313 		case 'd':
314 			if (desc != NULL)
315 				free(desc);
316 			desc = strdup(optarg);
317 			break;
318 		default:
319 			usage();
320 			break;
321 		}
322 	}
323 
324 	if (desc == NULL)
325 		desc = strdup("zhack injected");
326 	feature.fi_desc = desc;
327 
328 	argc -= optind;
329 	argv += optind;
330 
331 	if (argc < 2) {
332 		(void) fprintf(stderr, "error: missing feature or pool name\n");
333 		usage();
334 	}
335 	target = argv[0];
336 	feature.fi_guid = argv[1];
337 
338 	if (!zfeature_is_valid_guid(feature.fi_guid))
339 		fatal(NULL, FTAG, "invalid feature guid: %s", feature.fi_guid);
340 
341 	zhack_spa_open(target, B_FALSE, FTAG, &spa);
342 	mos = spa->spa_meta_objset;
343 
344 	if (zfeature_is_supported(feature.fi_guid))
345 		fatal(spa, FTAG, "'%s' is a real feature, will not enable",
346 		    feature.fi_guid);
347 	if (0 == zap_contains(mos, spa->spa_feat_desc_obj, feature.fi_guid))
348 		fatal(spa, FTAG, "feature already enabled: %s",
349 		    feature.fi_guid);
350 
351 	VERIFY0(dsl_sync_task(spa_name(spa), NULL,
352 	    zhack_feature_enable_sync, &feature, 5, ZFS_SPACE_CHECK_NORMAL));
353 
354 	spa_close(spa, FTAG);
355 
356 	free(desc);
357 }
358 
359 static void
feature_incr_sync(void * arg,dmu_tx_t * tx)360 feature_incr_sync(void *arg, dmu_tx_t *tx)
361 {
362 	spa_t *spa = dmu_tx_pool(tx)->dp_spa;
363 	zfeature_info_t *feature = arg;
364 	uint64_t refcount;
365 
366 	VERIFY0(feature_get_refcount_from_disk(spa, feature, &refcount));
367 	feature_sync(spa, feature, refcount + 1, tx);
368 	spa_history_log_internal(spa, "zhack feature incr", tx,
369 	    "name=%s", feature->fi_guid);
370 }
371 
372 static void
feature_decr_sync(void * arg,dmu_tx_t * tx)373 feature_decr_sync(void *arg, dmu_tx_t *tx)
374 {
375 	spa_t *spa = dmu_tx_pool(tx)->dp_spa;
376 	zfeature_info_t *feature = arg;
377 	uint64_t refcount;
378 
379 	VERIFY0(feature_get_refcount_from_disk(spa, feature, &refcount));
380 	feature_sync(spa, feature, refcount - 1, tx);
381 	spa_history_log_internal(spa, "zhack feature decr", tx,
382 	    "name=%s", feature->fi_guid);
383 }
384 
385 static void
zhack_do_feature_ref(int argc,char ** argv)386 zhack_do_feature_ref(int argc, char **argv)
387 {
388 	int c;
389 	char *target;
390 	boolean_t decr = B_FALSE;
391 	spa_t *spa;
392 	objset_t *mos;
393 	zfeature_info_t feature;
394 	const spa_feature_t nodeps[] = { SPA_FEATURE_NONE };
395 
396 	/*
397 	 * fi_desc does not matter here because it was written to disk
398 	 * when the feature was enabled, but we need to properly set the
399 	 * feature for read or write based on the information we read off
400 	 * disk later.
401 	 */
402 	feature.fi_uname = "zhack";
403 	feature.fi_flags = 0;
404 	feature.fi_desc = NULL;
405 	feature.fi_depends = nodeps;
406 	feature.fi_feature = SPA_FEATURE_NONE;
407 
408 	optind = 1;
409 	while ((c = getopt(argc, argv, "+md")) != -1) {
410 		switch (c) {
411 		case 'm':
412 			feature.fi_flags |= ZFEATURE_FLAG_MOS;
413 			break;
414 		case 'd':
415 			decr = B_TRUE;
416 			break;
417 		default:
418 			usage();
419 			break;
420 		}
421 	}
422 	argc -= optind;
423 	argv += optind;
424 
425 	if (argc < 2) {
426 		(void) fprintf(stderr, "error: missing feature or pool name\n");
427 		usage();
428 	}
429 	target = argv[0];
430 	feature.fi_guid = argv[1];
431 
432 	if (!zfeature_is_valid_guid(feature.fi_guid))
433 		fatal(NULL, FTAG, "invalid feature guid: %s", feature.fi_guid);
434 
435 	zhack_spa_open(target, B_FALSE, FTAG, &spa);
436 	mos = spa->spa_meta_objset;
437 
438 	if (zfeature_is_supported(feature.fi_guid)) {
439 		fatal(spa, FTAG,
440 		    "'%s' is a real feature, will not change refcount",
441 		    feature.fi_guid);
442 	}
443 
444 	if (0 == zap_contains(mos, spa->spa_feat_for_read_obj,
445 	    feature.fi_guid)) {
446 		feature.fi_flags &= ~ZFEATURE_FLAG_READONLY_COMPAT;
447 	} else if (0 == zap_contains(mos, spa->spa_feat_for_write_obj,
448 	    feature.fi_guid)) {
449 		feature.fi_flags |= ZFEATURE_FLAG_READONLY_COMPAT;
450 	} else {
451 		fatal(spa, FTAG, "feature is not enabled: %s", feature.fi_guid);
452 	}
453 
454 	if (decr) {
455 		uint64_t count;
456 		if (feature_get_refcount_from_disk(spa, &feature,
457 		    &count) == 0 && count == 0) {
458 			fatal(spa, FTAG, "feature refcount already 0: %s",
459 			    feature.fi_guid);
460 		}
461 	}
462 
463 	VERIFY0(dsl_sync_task(spa_name(spa), NULL,
464 	    decr ? feature_decr_sync : feature_incr_sync, &feature,
465 	    5, ZFS_SPACE_CHECK_NORMAL));
466 
467 	spa_close(spa, FTAG);
468 }
469 
470 static int
zhack_do_feature(int argc,char ** argv)471 zhack_do_feature(int argc, char **argv)
472 {
473 	char *subcommand;
474 
475 	argc--;
476 	argv++;
477 	if (argc == 0) {
478 		(void) fprintf(stderr,
479 		    "error: no feature operation specified\n");
480 		usage();
481 	}
482 
483 	subcommand = argv[0];
484 	if (strcmp(subcommand, "stat") == 0) {
485 		zhack_do_feature_stat(argc, argv);
486 	} else if (strcmp(subcommand, "enable") == 0) {
487 		zhack_do_feature_enable(argc, argv);
488 	} else if (strcmp(subcommand, "ref") == 0) {
489 		zhack_do_feature_ref(argc, argv);
490 	} else {
491 		(void) fprintf(stderr, "error: unknown subcommand: %s\n",
492 		    subcommand);
493 		usage();
494 	}
495 
496 	return (0);
497 }
498 
499 #define	ASHIFT_UBERBLOCK_SHIFT(ashift)	\
500 	MIN(MAX(ashift, UBERBLOCK_SHIFT), \
501 	MAX_UBERBLOCK_SHIFT)
502 #define	ASHIFT_UBERBLOCK_SIZE(ashift) \
503 	(1ULL << ASHIFT_UBERBLOCK_SHIFT(ashift))
504 
505 #define	REPAIR_LABEL_STATUS_CKSUM (1 << 0)
506 #define	REPAIR_LABEL_STATUS_UB    (1 << 1)
507 
508 static int
zhack_repair_read_label(const int fd,vdev_label_t * vl,const uint64_t label_offset,const int l)509 zhack_repair_read_label(const int fd, vdev_label_t *vl,
510     const uint64_t label_offset, const int l)
511 {
512 	const int err = pread64(fd, vl, sizeof (vdev_label_t), label_offset);
513 
514 	if (err == -1) {
515 		(void) fprintf(stderr,
516 		    "error: cannot read label %d: %s\n",
517 		    l, strerror(errno));
518 		return (err);
519 	} else if (err != sizeof (vdev_label_t)) {
520 		(void) fprintf(stderr,
521 		    "error: bad label %d read size\n", l);
522 		return (err);
523 	}
524 
525 	return (0);
526 }
527 
528 static void
zhack_repair_calc_cksum(const int byteswap,void * data,const uint64_t offset,const uint64_t abdsize,zio_eck_t * eck,zio_cksum_t * cksum)529 zhack_repair_calc_cksum(const int byteswap, void *data, const uint64_t offset,
530     const uint64_t abdsize, zio_eck_t *eck, zio_cksum_t *cksum)
531 {
532 	zio_cksum_t verifier;
533 	zio_cksum_t current_cksum;
534 	zio_checksum_info_t *ci;
535 	abd_t *abd;
536 
537 	ZIO_SET_CHECKSUM(&verifier, offset, 0, 0, 0);
538 
539 	if (byteswap)
540 		byteswap_uint64_array(&verifier, sizeof (zio_cksum_t));
541 
542 	current_cksum = eck->zec_cksum;
543 	eck->zec_cksum = verifier;
544 
545 	ci = &zio_checksum_table[ZIO_CHECKSUM_LABEL];
546 	abd = abd_get_from_buf(data, abdsize);
547 	ci->ci_func[byteswap](abd, abdsize, NULL, cksum);
548 	abd_free(abd);
549 
550 	eck->zec_cksum = current_cksum;
551 }
552 
553 static int
zhack_repair_check_label(uberblock_t * ub,const int l,const char ** cfg_keys,const size_t cfg_keys_len,nvlist_t * cfg,nvlist_t * vdev_tree_cfg,uint64_t * ashift)554 zhack_repair_check_label(uberblock_t *ub, const int l, const char **cfg_keys,
555     const size_t cfg_keys_len, nvlist_t *cfg, nvlist_t *vdev_tree_cfg,
556     uint64_t *ashift)
557 {
558 	int err;
559 
560 	if (ub->ub_txg != 0) {
561 		(void) fprintf(stderr,
562 		    "error: label %d: UB TXG of 0 expected, but got %"
563 		    PRIu64 "\n",
564 		    l, ub->ub_txg);
565 		(void) fprintf(stderr, "It would appear the device was not "
566 		    "properly removed.\n");
567 		return (1);
568 	}
569 
570 	for (int i = 0; i < cfg_keys_len; i++) {
571 		uint64_t val;
572 		err = nvlist_lookup_uint64(cfg, cfg_keys[i], &val);
573 		if (err) {
574 			(void) fprintf(stderr,
575 			    "error: label %d, %d: "
576 			    "cannot find nvlist key %s\n",
577 			    l, i, cfg_keys[i]);
578 			return (err);
579 		}
580 	}
581 
582 	err = nvlist_lookup_nvlist(cfg,
583 	    ZPOOL_CONFIG_VDEV_TREE, &vdev_tree_cfg);
584 	if (err) {
585 		(void) fprintf(stderr,
586 		    "error: label %d: cannot find nvlist key %s\n",
587 		    l, ZPOOL_CONFIG_VDEV_TREE);
588 		return (err);
589 	}
590 
591 	err = nvlist_lookup_uint64(vdev_tree_cfg,
592 	    ZPOOL_CONFIG_ASHIFT, ashift);
593 	if (err) {
594 		(void) fprintf(stderr,
595 		    "error: label %d: cannot find nvlist key %s\n",
596 		    l, ZPOOL_CONFIG_ASHIFT);
597 		return (err);
598 	}
599 
600 	if (*ashift == 0) {
601 		(void) fprintf(stderr,
602 		    "error: label %d: nvlist key %s is zero\n",
603 		    l, ZPOOL_CONFIG_ASHIFT);
604 		return (err);
605 	}
606 
607 	return (0);
608 }
609 
610 static int
zhack_repair_undetach(uberblock_t * ub,nvlist_t * cfg,const int l)611 zhack_repair_undetach(uberblock_t *ub, nvlist_t *cfg, const int l)
612 {
613 	/*
614 	 * Uberblock root block pointer has valid birth TXG.
615 	 * Copying it to the label NVlist
616 	 */
617 	if (BP_GET_LOGICAL_BIRTH(&ub->ub_rootbp) != 0) {
618 		const uint64_t txg = BP_GET_LOGICAL_BIRTH(&ub->ub_rootbp);
619 		ub->ub_txg = txg;
620 
621 		if (nvlist_remove_all(cfg, ZPOOL_CONFIG_CREATE_TXG) != 0) {
622 			(void) fprintf(stderr,
623 			    "error: label %d: "
624 			    "Failed to remove pool creation TXG\n",
625 			    l);
626 			return (1);
627 		}
628 
629 		if (nvlist_remove_all(cfg, ZPOOL_CONFIG_POOL_TXG) != 0) {
630 			(void) fprintf(stderr,
631 			    "error: label %d: Failed to remove pool TXG to "
632 			    "be replaced.\n",
633 			    l);
634 			return (1);
635 		}
636 
637 		if (nvlist_add_uint64(cfg, ZPOOL_CONFIG_POOL_TXG, txg) != 0) {
638 			(void) fprintf(stderr,
639 			    "error: label %d: "
640 			    "Failed to add pool TXG of %" PRIu64 "\n",
641 			    l, txg);
642 			return (1);
643 		}
644 	}
645 
646 	return (0);
647 }
648 
649 static boolean_t
zhack_repair_write_label(const int l,const int fd,const int byteswap,void * data,zio_eck_t * eck,const uint64_t offset,const uint64_t abdsize)650 zhack_repair_write_label(const int l, const int fd, const int byteswap,
651     void *data, zio_eck_t *eck, const uint64_t offset, const uint64_t abdsize)
652 {
653 	zio_cksum_t actual_cksum;
654 	zhack_repair_calc_cksum(byteswap, data, offset, abdsize, eck,
655 	    &actual_cksum);
656 	zio_cksum_t expected_cksum = eck->zec_cksum;
657 	ssize_t err;
658 
659 	if (ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum))
660 		return (B_FALSE);
661 
662 	eck->zec_cksum = actual_cksum;
663 
664 	err = pwrite64(fd, data, abdsize, offset);
665 	if (err == -1) {
666 		(void) fprintf(stderr, "error: cannot write label %d: %s\n",
667 		    l, strerror(errno));
668 		return (B_FALSE);
669 	} else if (err != abdsize) {
670 		(void) fprintf(stderr, "error: bad write size label %d\n", l);
671 		return (B_FALSE);
672 	} else {
673 		(void) fprintf(stderr,
674 		    "label %d: wrote %" PRIu64 " bytes at offset %" PRIu64 "\n",
675 		    l, abdsize, offset);
676 	}
677 
678 	return (B_TRUE);
679 }
680 
681 static void
zhack_repair_write_uberblock(vdev_label_t * vl,const int l,const uint64_t ashift,const int fd,const int byteswap,const uint64_t label_offset,uint32_t * labels_repaired)682 zhack_repair_write_uberblock(vdev_label_t *vl, const int l,
683     const uint64_t ashift, const int fd, const int byteswap,
684     const uint64_t label_offset, uint32_t *labels_repaired)
685 {
686 	void *ub_data =
687 	    (char *)vl + offsetof(vdev_label_t, vl_uberblock);
688 	zio_eck_t *ub_eck =
689 	    (zio_eck_t *)
690 	    ((char *)(ub_data) + (ASHIFT_UBERBLOCK_SIZE(ashift))) - 1;
691 
692 	if (ub_eck->zec_magic != 0) {
693 		(void) fprintf(stderr,
694 		    "error: label %d: "
695 		    "Expected Uberblock checksum magic number to "
696 		    "be 0, but got %" PRIu64 "\n",
697 		    l, ub_eck->zec_magic);
698 		(void) fprintf(stderr, "It would appear there's already "
699 		    "a checksum for the uberblock.\n");
700 		return;
701 	}
702 
703 
704 	ub_eck->zec_magic = byteswap ? BSWAP_64(ZEC_MAGIC) : ZEC_MAGIC;
705 
706 	if (zhack_repair_write_label(l, fd, byteswap,
707 	    ub_data, ub_eck,
708 	    label_offset + offsetof(vdev_label_t, vl_uberblock),
709 	    ASHIFT_UBERBLOCK_SIZE(ashift)))
710 			labels_repaired[l] |= REPAIR_LABEL_STATUS_UB;
711 }
712 
713 static void
zhack_repair_print_cksum(FILE * stream,const zio_cksum_t * cksum)714 zhack_repair_print_cksum(FILE *stream, const zio_cksum_t *cksum)
715 {
716 	(void) fprintf(stream,
717 	    "%016llx:%016llx:%016llx:%016llx",
718 	    (u_longlong_t)cksum->zc_word[0],
719 	    (u_longlong_t)cksum->zc_word[1],
720 	    (u_longlong_t)cksum->zc_word[2],
721 	    (u_longlong_t)cksum->zc_word[3]);
722 }
723 
724 static int
zhack_repair_test_cksum(const int byteswap,void * vdev_data,zio_eck_t * vdev_eck,const uint64_t vdev_phys_offset,const int l)725 zhack_repair_test_cksum(const int byteswap, void *vdev_data,
726     zio_eck_t *vdev_eck, const uint64_t vdev_phys_offset, const int l)
727 {
728 	const zio_cksum_t expected_cksum = vdev_eck->zec_cksum;
729 	zio_cksum_t actual_cksum;
730 	zhack_repair_calc_cksum(byteswap, vdev_data, vdev_phys_offset,
731 	    VDEV_PHYS_SIZE, vdev_eck, &actual_cksum);
732 	const uint64_t expected_magic = byteswap ?
733 	    BSWAP_64(ZEC_MAGIC) : ZEC_MAGIC;
734 	const uint64_t actual_magic = vdev_eck->zec_magic;
735 	int err = 0;
736 	if (actual_magic != expected_magic) {
737 		(void) fprintf(stderr, "error: label %d: "
738 		    "Expected "
739 		    "the nvlist checksum magic number to not be %"
740 		    PRIu64 " not %" PRIu64 "\n",
741 		    l, expected_magic, actual_magic);
742 		err = ECKSUM;
743 	}
744 	if (!ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum)) {
745 		(void) fprintf(stderr, "error: label %d: "
746 		    "Expected the nvlist checksum to be ", l);
747 		(void) zhack_repair_print_cksum(stderr,
748 		    &expected_cksum);
749 		(void) fprintf(stderr, " not ");
750 		zhack_repair_print_cksum(stderr, &actual_cksum);
751 		(void) fprintf(stderr, "\n");
752 		err = ECKSUM;
753 	}
754 	return (err);
755 }
756 
757 static void
zhack_repair_one_label(const zhack_repair_op_t op,const int fd,vdev_label_t * vl,const uint64_t label_offset,const int l,uint32_t * labels_repaired)758 zhack_repair_one_label(const zhack_repair_op_t op, const int fd,
759     vdev_label_t *vl, const uint64_t label_offset, const int l,
760     uint32_t *labels_repaired)
761 {
762 	ssize_t err;
763 	uberblock_t *ub = (uberblock_t *)vl->vl_uberblock;
764 	void *vdev_data =
765 	    (char *)vl + offsetof(vdev_label_t, vl_vdev_phys);
766 	zio_eck_t *vdev_eck =
767 	    (zio_eck_t *)((char *)(vdev_data) + VDEV_PHYS_SIZE) - 1;
768 	const uint64_t vdev_phys_offset =
769 	    label_offset + offsetof(vdev_label_t, vl_vdev_phys);
770 	const char *cfg_keys[] = { ZPOOL_CONFIG_VERSION,
771 	    ZPOOL_CONFIG_POOL_STATE, ZPOOL_CONFIG_GUID };
772 	nvlist_t *cfg;
773 	nvlist_t *vdev_tree_cfg = NULL;
774 	uint64_t ashift;
775 	int byteswap;
776 
777 	err = zhack_repair_read_label(fd, vl, label_offset, l);
778 	if (err)
779 		return;
780 
781 	if (vdev_eck->zec_magic == 0) {
782 		(void) fprintf(stderr, "error: label %d: "
783 		    "Expected the nvlist checksum magic number to not be zero"
784 		    "\n",
785 		    l);
786 		(void) fprintf(stderr, "There should already be a checksum "
787 		    "for the label.\n");
788 		return;
789 	}
790 
791 	byteswap =
792 	    (vdev_eck->zec_magic == BSWAP_64((uint64_t)ZEC_MAGIC));
793 
794 	if (byteswap) {
795 		byteswap_uint64_array(&vdev_eck->zec_cksum,
796 		    sizeof (zio_cksum_t));
797 		vdev_eck->zec_magic = BSWAP_64(vdev_eck->zec_magic);
798 	}
799 
800 	if ((op & ZHACK_REPAIR_OP_CKSUM) == 0 &&
801 	    zhack_repair_test_cksum(byteswap, vdev_data, vdev_eck,
802 	    vdev_phys_offset, l) != 0) {
803 		(void) fprintf(stderr, "It would appear checksums are "
804 		    "corrupted. Try zhack repair label -c <device>\n");
805 		return;
806 	}
807 
808 	err = nvlist_unpack(vl->vl_vdev_phys.vp_nvlist,
809 	    VDEV_PHYS_SIZE - sizeof (zio_eck_t), &cfg, 0);
810 	if (err) {
811 		(void) fprintf(stderr,
812 		    "error: cannot unpack nvlist label %d\n", l);
813 		return;
814 	}
815 
816 	err = zhack_repair_check_label(ub,
817 	    l, cfg_keys, ARRAY_SIZE(cfg_keys), cfg, vdev_tree_cfg, &ashift);
818 	if (err)
819 		return;
820 
821 	if ((op & ZHACK_REPAIR_OP_UNDETACH) != 0) {
822 		char *buf;
823 		size_t buflen;
824 
825 		err = zhack_repair_undetach(ub, cfg, l);
826 		if (err)
827 			return;
828 
829 		buf = vl->vl_vdev_phys.vp_nvlist;
830 		buflen = VDEV_PHYS_SIZE - sizeof (zio_eck_t);
831 		if (nvlist_pack(cfg, &buf, &buflen, NV_ENCODE_XDR, 0) != 0) {
832 			(void) fprintf(stderr,
833 			    "error: label %d: Failed to pack nvlist\n", l);
834 			return;
835 		}
836 
837 		zhack_repair_write_uberblock(vl,
838 		    l, ashift, fd, byteswap, label_offset, labels_repaired);
839 	}
840 
841 	if (zhack_repair_write_label(l, fd, byteswap, vdev_data, vdev_eck,
842 	    vdev_phys_offset, VDEV_PHYS_SIZE))
843 			labels_repaired[l] |= REPAIR_LABEL_STATUS_CKSUM;
844 
845 	fsync(fd);
846 }
847 
848 static const char *
zhack_repair_label_status(const uint32_t label_status,const uint32_t to_check)849 zhack_repair_label_status(const uint32_t label_status,
850     const uint32_t to_check)
851 {
852 	return ((label_status & to_check) != 0 ? "repaired" : "skipped");
853 }
854 
855 static int
zhack_label_repair(const zhack_repair_op_t op,const int argc,char ** argv)856 zhack_label_repair(const zhack_repair_op_t op, const int argc, char **argv)
857 {
858 	uint32_t labels_repaired[VDEV_LABELS] = {0};
859 	vdev_label_t labels[VDEV_LABELS] = {{{0}}};
860 	struct stat64 st;
861 	int fd;
862 	off_t filesize;
863 	uint32_t repaired = 0;
864 
865 	abd_init();
866 
867 	if (argc < 1) {
868 		(void) fprintf(stderr, "error: missing device\n");
869 		usage();
870 	}
871 
872 	if ((fd = open(argv[0], O_RDWR)) == -1)
873 		fatal(NULL, FTAG, "cannot open '%s': %s", argv[0],
874 		    strerror(errno));
875 
876 	if (fstat64_blk(fd, &st) != 0)
877 		fatal(NULL, FTAG, "cannot stat '%s': %s", argv[0],
878 		    strerror(errno));
879 
880 	filesize = st.st_size;
881 	(void) fprintf(stderr, "Calculated filesize to be %jd\n",
882 	    (intmax_t)filesize);
883 
884 	if (filesize % sizeof (vdev_label_t) != 0)
885 		filesize =
886 		    (filesize / sizeof (vdev_label_t)) * sizeof (vdev_label_t);
887 
888 	for (int l = 0; l < VDEV_LABELS; l++) {
889 		zhack_repair_one_label(op, fd, &labels[l],
890 		    vdev_label_offset(filesize, l, 0), l, labels_repaired);
891 	}
892 
893 	close(fd);
894 
895 	abd_fini();
896 
897 	for (int l = 0; l < VDEV_LABELS; l++) {
898 		const uint32_t lr = labels_repaired[l];
899 		(void) printf("label %d: ", l);
900 		(void) printf("uberblock: %s ",
901 		    zhack_repair_label_status(lr, REPAIR_LABEL_STATUS_UB));
902 		(void) printf("checksum: %s\n",
903 		    zhack_repair_label_status(lr, REPAIR_LABEL_STATUS_CKSUM));
904 		repaired |= lr;
905 	}
906 
907 	if (repaired > 0)
908 		return (0);
909 
910 	return (1);
911 }
912 
913 static int
zhack_do_label_repair(int argc,char ** argv)914 zhack_do_label_repair(int argc, char **argv)
915 {
916 	zhack_repair_op_t op = ZHACK_REPAIR_OP_UNKNOWN;
917 	int c;
918 
919 	optind = 1;
920 	while ((c = getopt(argc, argv, "+cu")) != -1) {
921 		switch (c) {
922 		case 'c':
923 			op |= ZHACK_REPAIR_OP_CKSUM;
924 			break;
925 		case 'u':
926 			op |= ZHACK_REPAIR_OP_UNDETACH;
927 			break;
928 		default:
929 			usage();
930 			break;
931 		}
932 	}
933 
934 	argc -= optind;
935 	argv += optind;
936 
937 	if (op == ZHACK_REPAIR_OP_UNKNOWN)
938 		op = ZHACK_REPAIR_OP_CKSUM;
939 
940 	return (zhack_label_repair(op, argc, argv));
941 }
942 
943 static int
zhack_do_label(int argc,char ** argv)944 zhack_do_label(int argc, char **argv)
945 {
946 	char *subcommand;
947 	int err;
948 
949 	argc--;
950 	argv++;
951 	if (argc == 0) {
952 		(void) fprintf(stderr,
953 		    "error: no label operation specified\n");
954 		usage();
955 	}
956 
957 	subcommand = argv[0];
958 	if (strcmp(subcommand, "repair") == 0) {
959 		err = zhack_do_label_repair(argc, argv);
960 	} else {
961 		(void) fprintf(stderr, "error: unknown subcommand: %s\n",
962 		    subcommand);
963 		usage();
964 	}
965 
966 	return (err);
967 }
968 
969 #define	MAX_NUM_PATHS 1024
970 
971 int
main(int argc,char ** argv)972 main(int argc, char **argv)
973 {
974 	char *path[MAX_NUM_PATHS];
975 	const char *subcommand;
976 	int rv = 0;
977 	int c;
978 
979 	g_importargs.path = path;
980 
981 	dprintf_setup(&argc, argv);
982 	zfs_prop_init();
983 
984 	while ((c = getopt(argc, argv, "+c:d:")) != -1) {
985 		switch (c) {
986 		case 'c':
987 			g_importargs.cachefile = optarg;
988 			break;
989 		case 'd':
990 			assert(g_importargs.paths < MAX_NUM_PATHS);
991 			g_importargs.path[g_importargs.paths++] = optarg;
992 			break;
993 		default:
994 			usage();
995 			break;
996 		}
997 	}
998 
999 	argc -= optind;
1000 	argv += optind;
1001 	optind = 1;
1002 
1003 	if (argc == 0) {
1004 		(void) fprintf(stderr, "error: no command specified\n");
1005 		usage();
1006 	}
1007 
1008 	subcommand = argv[0];
1009 
1010 	if (strcmp(subcommand, "feature") == 0) {
1011 		rv = zhack_do_feature(argc, argv);
1012 	} else if (strcmp(subcommand, "label") == 0) {
1013 		return (zhack_do_label(argc, argv));
1014 	} else {
1015 		(void) fprintf(stderr, "error: unknown subcommand: %s\n",
1016 		    subcommand);
1017 		usage();
1018 	}
1019 
1020 	if (!g_readonly && spa_export(g_pool, NULL, B_TRUE, B_FALSE) != 0) {
1021 		fatal(NULL, FTAG, "pool export failed; "
1022 		    "changes may not be committed to disk\n");
1023 	}
1024 
1025 	kernel_fini();
1026 
1027 	return (rv);
1028 }
1029