xref: /freebsd/sys/contrib/openzfs/module/zfs/zio_checksum.c (revision e9e8876a4d6afc1ad5315faaa191b25121a813d7)
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 http://www.opensolaris.org/os/licensing.
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  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2013, 2016 by Delphix. All rights reserved.
24  * Copyright 2013 Saso Kiselkov. All rights reserved.
25  */
26 
27 #include <sys/zfs_context.h>
28 #include <sys/spa.h>
29 #include <sys/spa_impl.h>
30 #include <sys/zio.h>
31 #include <sys/zio_checksum.h>
32 #include <sys/zil.h>
33 #include <sys/abd.h>
34 #include <zfs_fletcher.h>
35 
36 /*
37  * Checksum vectors.
38  *
39  * In the SPA, everything is checksummed.  We support checksum vectors
40  * for three distinct reasons:
41  *
42  *   1. Different kinds of data need different levels of protection.
43  *	For SPA metadata, we always want a very strong checksum.
44  *	For user data, we let users make the trade-off between speed
45  *	and checksum strength.
46  *
47  *   2. Cryptographic hash and MAC algorithms are an area of active research.
48  *	It is likely that in future hash functions will be at least as strong
49  *	as current best-of-breed, and may be substantially faster as well.
50  *	We want the ability to take advantage of these new hashes as soon as
51  *	they become available.
52  *
53  *   3. If someone develops hardware that can compute a strong hash quickly,
54  *	we want the ability to take advantage of that hardware.
55  *
56  * Of course, we don't want a checksum upgrade to invalidate existing
57  * data, so we store the checksum *function* in eight bits of the bp.
58  * This gives us room for up to 256 different checksum functions.
59  *
60  * When writing a block, we always checksum it with the latest-and-greatest
61  * checksum function of the appropriate strength.  When reading a block,
62  * we compare the expected checksum against the actual checksum, which we
63  * compute via the checksum function specified by BP_GET_CHECKSUM(bp).
64  *
65  * SALTED CHECKSUMS
66  *
67  * To enable the use of less secure hash algorithms with dedup, we
68  * introduce the notion of salted checksums (MACs, really).  A salted
69  * checksum is fed both a random 256-bit value (the salt) and the data
70  * to be checksummed.  This salt is kept secret (stored on the pool, but
71  * never shown to the user).  Thus even if an attacker knew of collision
72  * weaknesses in the hash algorithm, they won't be able to mount a known
73  * plaintext attack on the DDT, since the actual hash value cannot be
74  * known ahead of time.  How the salt is used is algorithm-specific
75  * (some might simply prefix it to the data block, others might need to
76  * utilize a full-blown HMAC).  On disk the salt is stored in a ZAP
77  * object in the MOS (DMU_POOL_CHECKSUM_SALT).
78  *
79  * CONTEXT TEMPLATES
80  *
81  * Some hashing algorithms need to perform a substantial amount of
82  * initialization work (e.g. salted checksums above may need to pre-hash
83  * the salt) before being able to process data.  Performing this
84  * redundant work for each block would be wasteful, so we instead allow
85  * a checksum algorithm to do the work once (the first time it's used)
86  * and then keep this pre-initialized context as a template inside the
87  * spa_t (spa_cksum_tmpls).  If the zio_checksum_info_t contains
88  * non-NULL ci_tmpl_init and ci_tmpl_free callbacks, they are used to
89  * construct and destruct the pre-initialized checksum context.  The
90  * pre-initialized context is then reused during each checksum
91  * invocation and passed to the checksum function.
92  */
93 
94 /*ARGSUSED*/
95 static void
96 abd_checksum_off(abd_t *abd, uint64_t size,
97     const void *ctx_template, zio_cksum_t *zcp)
98 {
99 	ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0);
100 }
101 
102 /*ARGSUSED*/
103 static void
104 abd_fletcher_2_native(abd_t *abd, uint64_t size,
105     const void *ctx_template, zio_cksum_t *zcp)
106 {
107 	fletcher_init(zcp);
108 	(void) abd_iterate_func(abd, 0, size,
109 	    fletcher_2_incremental_native, zcp);
110 }
111 
112 /*ARGSUSED*/
113 static void
114 abd_fletcher_2_byteswap(abd_t *abd, uint64_t size,
115     const void *ctx_template, zio_cksum_t *zcp)
116 {
117 	fletcher_init(zcp);
118 	(void) abd_iterate_func(abd, 0, size,
119 	    fletcher_2_incremental_byteswap, zcp);
120 }
121 
122 static inline void
123 abd_fletcher_4_impl(abd_t *abd, uint64_t size, zio_abd_checksum_data_t *acdp)
124 {
125 	fletcher_4_abd_ops.acf_init(acdp);
126 	abd_iterate_func(abd, 0, size, fletcher_4_abd_ops.acf_iter, acdp);
127 	fletcher_4_abd_ops.acf_fini(acdp);
128 }
129 
130 /*ARGSUSED*/
131 void
132 abd_fletcher_4_native(abd_t *abd, uint64_t size,
133     const void *ctx_template, zio_cksum_t *zcp)
134 {
135 	fletcher_4_ctx_t ctx;
136 
137 	zio_abd_checksum_data_t acd = {
138 		.acd_byteorder	= ZIO_CHECKSUM_NATIVE,
139 		.acd_zcp 	= zcp,
140 		.acd_ctx	= &ctx
141 	};
142 
143 	abd_fletcher_4_impl(abd, size, &acd);
144 
145 }
146 
147 /*ARGSUSED*/
148 void
149 abd_fletcher_4_byteswap(abd_t *abd, uint64_t size,
150     const void *ctx_template, zio_cksum_t *zcp)
151 {
152 	fletcher_4_ctx_t ctx;
153 
154 	zio_abd_checksum_data_t acd = {
155 		.acd_byteorder	= ZIO_CHECKSUM_BYTESWAP,
156 		.acd_zcp 	= zcp,
157 		.acd_ctx	= &ctx
158 	};
159 
160 	abd_fletcher_4_impl(abd, size, &acd);
161 }
162 
163 zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = {
164 	{{NULL, NULL}, NULL, NULL, 0, "inherit"},
165 	{{NULL, NULL}, NULL, NULL, 0, "on"},
166 	{{abd_checksum_off,		abd_checksum_off},
167 	    NULL, NULL, 0, "off"},
168 	{{abd_checksum_SHA256,		abd_checksum_SHA256},
169 	    NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_EMBEDDED,
170 	    "label"},
171 	{{abd_checksum_SHA256,		abd_checksum_SHA256},
172 	    NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_EMBEDDED,
173 	    "gang_header"},
174 	{{abd_fletcher_2_native,	abd_fletcher_2_byteswap},
175 	    NULL, NULL, ZCHECKSUM_FLAG_EMBEDDED, "zilog"},
176 	{{abd_fletcher_2_native,	abd_fletcher_2_byteswap},
177 	    NULL, NULL, 0, "fletcher2"},
178 	{{abd_fletcher_4_native,	abd_fletcher_4_byteswap},
179 	    NULL, NULL, ZCHECKSUM_FLAG_METADATA, "fletcher4"},
180 	{{abd_checksum_SHA256,		abd_checksum_SHA256},
181 	    NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_DEDUP |
182 	    ZCHECKSUM_FLAG_NOPWRITE, "sha256"},
183 	{{abd_fletcher_4_native,	abd_fletcher_4_byteswap},
184 	    NULL, NULL, ZCHECKSUM_FLAG_EMBEDDED, "zilog2"},
185 	{{abd_checksum_off,		abd_checksum_off},
186 	    NULL, NULL, 0, "noparity"},
187 	{{abd_checksum_SHA512_native,	abd_checksum_SHA512_byteswap},
188 	    NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_DEDUP |
189 	    ZCHECKSUM_FLAG_NOPWRITE, "sha512"},
190 	{{abd_checksum_skein_native,	abd_checksum_skein_byteswap},
191 	    abd_checksum_skein_tmpl_init, abd_checksum_skein_tmpl_free,
192 	    ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_DEDUP |
193 	    ZCHECKSUM_FLAG_SALTED | ZCHECKSUM_FLAG_NOPWRITE, "skein"},
194 	{{abd_checksum_edonr_native,	abd_checksum_edonr_byteswap},
195 	    abd_checksum_edonr_tmpl_init, abd_checksum_edonr_tmpl_free,
196 	    ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_SALTED |
197 	    ZCHECKSUM_FLAG_NOPWRITE, "edonr"},
198 };
199 
200 /*
201  * The flag corresponding to the "verify" in dedup=[checksum,]verify
202  * must be cleared first, so callers should use ZIO_CHECKSUM_MASK.
203  */
204 spa_feature_t
205 zio_checksum_to_feature(enum zio_checksum cksum)
206 {
207 	VERIFY((cksum & ~ZIO_CHECKSUM_MASK) == 0);
208 
209 	switch (cksum) {
210 	case ZIO_CHECKSUM_SHA512:
211 		return (SPA_FEATURE_SHA512);
212 	case ZIO_CHECKSUM_SKEIN:
213 		return (SPA_FEATURE_SKEIN);
214 	case ZIO_CHECKSUM_EDONR:
215 		return (SPA_FEATURE_EDONR);
216 	default:
217 		return (SPA_FEATURE_NONE);
218 	}
219 }
220 
221 enum zio_checksum
222 zio_checksum_select(enum zio_checksum child, enum zio_checksum parent)
223 {
224 	ASSERT(child < ZIO_CHECKSUM_FUNCTIONS);
225 	ASSERT(parent < ZIO_CHECKSUM_FUNCTIONS);
226 	ASSERT(parent != ZIO_CHECKSUM_INHERIT && parent != ZIO_CHECKSUM_ON);
227 
228 	if (child == ZIO_CHECKSUM_INHERIT)
229 		return (parent);
230 
231 	if (child == ZIO_CHECKSUM_ON)
232 		return (ZIO_CHECKSUM_ON_VALUE);
233 
234 	return (child);
235 }
236 
237 enum zio_checksum
238 zio_checksum_dedup_select(spa_t *spa, enum zio_checksum child,
239     enum zio_checksum parent)
240 {
241 	ASSERT((child & ZIO_CHECKSUM_MASK) < ZIO_CHECKSUM_FUNCTIONS);
242 	ASSERT((parent & ZIO_CHECKSUM_MASK) < ZIO_CHECKSUM_FUNCTIONS);
243 	ASSERT(parent != ZIO_CHECKSUM_INHERIT && parent != ZIO_CHECKSUM_ON);
244 
245 	if (child == ZIO_CHECKSUM_INHERIT)
246 		return (parent);
247 
248 	if (child == ZIO_CHECKSUM_ON)
249 		return (spa_dedup_checksum(spa));
250 
251 	if (child == (ZIO_CHECKSUM_ON | ZIO_CHECKSUM_VERIFY))
252 		return (spa_dedup_checksum(spa) | ZIO_CHECKSUM_VERIFY);
253 
254 	ASSERT((zio_checksum_table[child & ZIO_CHECKSUM_MASK].ci_flags &
255 	    ZCHECKSUM_FLAG_DEDUP) ||
256 	    (child & ZIO_CHECKSUM_VERIFY) || child == ZIO_CHECKSUM_OFF);
257 
258 	return (child);
259 }
260 
261 /*
262  * Set the external verifier for a gang block based on <vdev, offset, txg>,
263  * a tuple which is guaranteed to be unique for the life of the pool.
264  */
265 static void
266 zio_checksum_gang_verifier(zio_cksum_t *zcp, const blkptr_t *bp)
267 {
268 	const dva_t *dva = BP_IDENTITY(bp);
269 	uint64_t txg = BP_PHYSICAL_BIRTH(bp);
270 
271 	ASSERT(BP_IS_GANG(bp));
272 
273 	ZIO_SET_CHECKSUM(zcp, DVA_GET_VDEV(dva), DVA_GET_OFFSET(dva), txg, 0);
274 }
275 
276 /*
277  * Set the external verifier for a label block based on its offset.
278  * The vdev is implicit, and the txg is unknowable at pool open time --
279  * hence the logic in vdev_uberblock_load() to find the most recent copy.
280  */
281 static void
282 zio_checksum_label_verifier(zio_cksum_t *zcp, uint64_t offset)
283 {
284 	ZIO_SET_CHECKSUM(zcp, offset, 0, 0, 0);
285 }
286 
287 /*
288  * Calls the template init function of a checksum which supports context
289  * templates and installs the template into the spa_t.
290  */
291 static void
292 zio_checksum_template_init(enum zio_checksum checksum, spa_t *spa)
293 {
294 	zio_checksum_info_t *ci = &zio_checksum_table[checksum];
295 
296 	if (ci->ci_tmpl_init == NULL)
297 		return;
298 	if (spa->spa_cksum_tmpls[checksum] != NULL)
299 		return;
300 
301 	VERIFY(ci->ci_tmpl_free != NULL);
302 	mutex_enter(&spa->spa_cksum_tmpls_lock);
303 	if (spa->spa_cksum_tmpls[checksum] == NULL) {
304 		spa->spa_cksum_tmpls[checksum] =
305 		    ci->ci_tmpl_init(&spa->spa_cksum_salt);
306 		VERIFY(spa->spa_cksum_tmpls[checksum] != NULL);
307 	}
308 	mutex_exit(&spa->spa_cksum_tmpls_lock);
309 }
310 
311 /* convenience function to update a checksum to accommodate an encryption MAC */
312 static void
313 zio_checksum_handle_crypt(zio_cksum_t *cksum, zio_cksum_t *saved, boolean_t xor)
314 {
315 	/*
316 	 * Weak checksums do not have their entropy spread evenly
317 	 * across the bits of the checksum. Therefore, when truncating
318 	 * a weak checksum we XOR the first 2 words with the last 2 so
319 	 * that we don't "lose" any entropy unnecessarily.
320 	 */
321 	if (xor) {
322 		cksum->zc_word[0] ^= cksum->zc_word[2];
323 		cksum->zc_word[1] ^= cksum->zc_word[3];
324 	}
325 
326 	cksum->zc_word[2] = saved->zc_word[2];
327 	cksum->zc_word[3] = saved->zc_word[3];
328 }
329 
330 /*
331  * Generate the checksum.
332  */
333 void
334 zio_checksum_compute(zio_t *zio, enum zio_checksum checksum,
335     abd_t *abd, uint64_t size)
336 {
337 	static const uint64_t zec_magic = ZEC_MAGIC;
338 	blkptr_t *bp = zio->io_bp;
339 	uint64_t offset = zio->io_offset;
340 	zio_checksum_info_t *ci = &zio_checksum_table[checksum];
341 	zio_cksum_t cksum, saved;
342 	spa_t *spa = zio->io_spa;
343 	boolean_t insecure = (ci->ci_flags & ZCHECKSUM_FLAG_DEDUP) == 0;
344 
345 	ASSERT((uint_t)checksum < ZIO_CHECKSUM_FUNCTIONS);
346 	ASSERT(ci->ci_func[0] != NULL);
347 
348 	zio_checksum_template_init(checksum, spa);
349 
350 	if (ci->ci_flags & ZCHECKSUM_FLAG_EMBEDDED) {
351 		zio_eck_t eck;
352 		size_t eck_offset;
353 
354 		bzero(&saved, sizeof (zio_cksum_t));
355 
356 		if (checksum == ZIO_CHECKSUM_ZILOG2) {
357 			zil_chain_t zilc;
358 			abd_copy_to_buf(&zilc, abd, sizeof (zil_chain_t));
359 
360 			size = P2ROUNDUP_TYPED(zilc.zc_nused, ZIL_MIN_BLKSZ,
361 			    uint64_t);
362 			eck = zilc.zc_eck;
363 			eck_offset = offsetof(zil_chain_t, zc_eck);
364 		} else {
365 			eck_offset = size - sizeof (zio_eck_t);
366 			abd_copy_to_buf_off(&eck, abd, eck_offset,
367 			    sizeof (zio_eck_t));
368 		}
369 
370 		if (checksum == ZIO_CHECKSUM_GANG_HEADER) {
371 			zio_checksum_gang_verifier(&eck.zec_cksum, bp);
372 		} else if (checksum == ZIO_CHECKSUM_LABEL) {
373 			zio_checksum_label_verifier(&eck.zec_cksum, offset);
374 		} else {
375 			saved = eck.zec_cksum;
376 			eck.zec_cksum = bp->blk_cksum;
377 		}
378 
379 		abd_copy_from_buf_off(abd, &zec_magic,
380 		    eck_offset + offsetof(zio_eck_t, zec_magic),
381 		    sizeof (zec_magic));
382 		abd_copy_from_buf_off(abd, &eck.zec_cksum,
383 		    eck_offset + offsetof(zio_eck_t, zec_cksum),
384 		    sizeof (zio_cksum_t));
385 
386 		ci->ci_func[0](abd, size, spa->spa_cksum_tmpls[checksum],
387 		    &cksum);
388 		if (bp != NULL && BP_USES_CRYPT(bp) &&
389 		    BP_GET_TYPE(bp) != DMU_OT_OBJSET)
390 			zio_checksum_handle_crypt(&cksum, &saved, insecure);
391 
392 		abd_copy_from_buf_off(abd, &cksum,
393 		    eck_offset + offsetof(zio_eck_t, zec_cksum),
394 		    sizeof (zio_cksum_t));
395 	} else {
396 		saved = bp->blk_cksum;
397 		ci->ci_func[0](abd, size, spa->spa_cksum_tmpls[checksum],
398 		    &cksum);
399 		if (BP_USES_CRYPT(bp) && BP_GET_TYPE(bp) != DMU_OT_OBJSET)
400 			zio_checksum_handle_crypt(&cksum, &saved, insecure);
401 		bp->blk_cksum = cksum;
402 	}
403 }
404 
405 int
406 zio_checksum_error_impl(spa_t *spa, const blkptr_t *bp,
407     enum zio_checksum checksum, abd_t *abd, uint64_t size, uint64_t offset,
408     zio_bad_cksum_t *info)
409 {
410 	zio_checksum_info_t *ci = &zio_checksum_table[checksum];
411 	zio_cksum_t actual_cksum, expected_cksum;
412 	zio_eck_t eck;
413 	int byteswap;
414 
415 	if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL)
416 		return (SET_ERROR(EINVAL));
417 
418 	zio_checksum_template_init(checksum, spa);
419 
420 	if (ci->ci_flags & ZCHECKSUM_FLAG_EMBEDDED) {
421 		zio_cksum_t verifier;
422 		size_t eck_offset;
423 
424 		if (checksum == ZIO_CHECKSUM_ZILOG2) {
425 			zil_chain_t zilc;
426 			uint64_t nused;
427 
428 			abd_copy_to_buf(&zilc, abd, sizeof (zil_chain_t));
429 
430 			eck = zilc.zc_eck;
431 			eck_offset = offsetof(zil_chain_t, zc_eck) +
432 			    offsetof(zio_eck_t, zec_cksum);
433 
434 			if (eck.zec_magic == ZEC_MAGIC) {
435 				nused = zilc.zc_nused;
436 			} else if (eck.zec_magic == BSWAP_64(ZEC_MAGIC)) {
437 				nused = BSWAP_64(zilc.zc_nused);
438 			} else {
439 				return (SET_ERROR(ECKSUM));
440 			}
441 
442 			if (nused > size) {
443 				return (SET_ERROR(ECKSUM));
444 			}
445 
446 			size = P2ROUNDUP_TYPED(nused, ZIL_MIN_BLKSZ, uint64_t);
447 		} else {
448 			eck_offset = size - sizeof (zio_eck_t);
449 			abd_copy_to_buf_off(&eck, abd, eck_offset,
450 			    sizeof (zio_eck_t));
451 			eck_offset += offsetof(zio_eck_t, zec_cksum);
452 		}
453 
454 		if (checksum == ZIO_CHECKSUM_GANG_HEADER)
455 			zio_checksum_gang_verifier(&verifier, bp);
456 		else if (checksum == ZIO_CHECKSUM_LABEL)
457 			zio_checksum_label_verifier(&verifier, offset);
458 		else
459 			verifier = bp->blk_cksum;
460 
461 		byteswap = (eck.zec_magic == BSWAP_64(ZEC_MAGIC));
462 
463 		if (byteswap)
464 			byteswap_uint64_array(&verifier, sizeof (zio_cksum_t));
465 
466 		expected_cksum = eck.zec_cksum;
467 
468 		abd_copy_from_buf_off(abd, &verifier, eck_offset,
469 		    sizeof (zio_cksum_t));
470 
471 		ci->ci_func[byteswap](abd, size,
472 		    spa->spa_cksum_tmpls[checksum], &actual_cksum);
473 
474 		abd_copy_from_buf_off(abd, &expected_cksum, eck_offset,
475 		    sizeof (zio_cksum_t));
476 
477 		if (byteswap) {
478 			byteswap_uint64_array(&expected_cksum,
479 			    sizeof (zio_cksum_t));
480 		}
481 	} else {
482 		byteswap = BP_SHOULD_BYTESWAP(bp);
483 		expected_cksum = bp->blk_cksum;
484 		ci->ci_func[byteswap](abd, size,
485 		    spa->spa_cksum_tmpls[checksum], &actual_cksum);
486 	}
487 
488 	/*
489 	 * MAC checksums are a special case since half of this checksum will
490 	 * actually be the encryption MAC. This will be verified by the
491 	 * decryption process, so we just check the truncated checksum now.
492 	 * Objset blocks use embedded MACs so we don't truncate the checksum
493 	 * for them.
494 	 */
495 	if (bp != NULL && BP_USES_CRYPT(bp) &&
496 	    BP_GET_TYPE(bp) != DMU_OT_OBJSET) {
497 		if (!(ci->ci_flags & ZCHECKSUM_FLAG_DEDUP)) {
498 			actual_cksum.zc_word[0] ^= actual_cksum.zc_word[2];
499 			actual_cksum.zc_word[1] ^= actual_cksum.zc_word[3];
500 		}
501 
502 		actual_cksum.zc_word[2] = 0;
503 		actual_cksum.zc_word[3] = 0;
504 		expected_cksum.zc_word[2] = 0;
505 		expected_cksum.zc_word[3] = 0;
506 	}
507 
508 	if (info != NULL) {
509 		info->zbc_expected = expected_cksum;
510 		info->zbc_actual = actual_cksum;
511 		info->zbc_checksum_name = ci->ci_name;
512 		info->zbc_byteswapped = byteswap;
513 		info->zbc_injected = 0;
514 		info->zbc_has_cksum = 1;
515 	}
516 
517 	if (!ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum))
518 		return (SET_ERROR(ECKSUM));
519 
520 	return (0);
521 }
522 
523 int
524 zio_checksum_error(zio_t *zio, zio_bad_cksum_t *info)
525 {
526 	blkptr_t *bp = zio->io_bp;
527 	uint_t checksum = (bp == NULL ? zio->io_prop.zp_checksum :
528 	    (BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : BP_GET_CHECKSUM(bp)));
529 	int error;
530 	uint64_t size = (bp == NULL ? zio->io_size :
531 	    (BP_IS_GANG(bp) ? SPA_GANGBLOCKSIZE : BP_GET_PSIZE(bp)));
532 	uint64_t offset = zio->io_offset;
533 	abd_t *data = zio->io_abd;
534 	spa_t *spa = zio->io_spa;
535 
536 	error = zio_checksum_error_impl(spa, bp, checksum, data, size,
537 	    offset, info);
538 
539 	if (zio_injection_enabled && error == 0 && zio->io_error == 0) {
540 		error = zio_handle_fault_injection(zio, ECKSUM);
541 		if (error != 0)
542 			info->zbc_injected = 1;
543 	}
544 
545 	return (error);
546 }
547 
548 /*
549  * Called by a spa_t that's about to be deallocated. This steps through
550  * all of the checksum context templates and deallocates any that were
551  * initialized using the algorithm-specific template init function.
552  */
553 void
554 zio_checksum_templates_free(spa_t *spa)
555 {
556 	for (enum zio_checksum checksum = 0;
557 	    checksum < ZIO_CHECKSUM_FUNCTIONS; checksum++) {
558 		if (spa->spa_cksum_tmpls[checksum] != NULL) {
559 			zio_checksum_info_t *ci = &zio_checksum_table[checksum];
560 
561 			VERIFY(ci->ci_tmpl_free != NULL);
562 			ci->ci_tmpl_free(spa->spa_cksum_tmpls[checksum]);
563 			spa->spa_cksum_tmpls[checksum] = NULL;
564 		}
565 	}
566 }
567