*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2013, 2016 by Delphix. All rights reserved.
+ * Copyright 2013 Saso Kiselkov. All rights reserved.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
+#include <sys/spa_impl.h>
#include <sys/zio.h>
#include <sys/zio_checksum.h>
#include <sys/zil.h>
+#include <sys/abd.h>
#include <zfs_fletcher.h>
/*
* checksum function of the appropriate strength. When reading a block,
* we compare the expected checksum against the actual checksum, which we
* compute via the checksum function specified by BP_GET_CHECKSUM(bp).
+ *
+ * SALTED CHECKSUMS
+ *
+ * To enable the use of less secure hash algorithms with dedup, we
+ * introduce the notion of salted checksums (MACs, really). A salted
+ * checksum is fed both a random 256-bit value (the salt) and the data
+ * to be checksummed. This salt is kept secret (stored on the pool, but
+ * never shown to the user). Thus even if an attacker knew of collision
+ * weaknesses in the hash algorithm, they won't be able to mount a known
+ * plaintext attack on the DDT, since the actual hash value cannot be
+ * known ahead of time. How the salt is used is algorithm-specific
+ * (some might simply prefix it to the data block, others might need to
+ * utilize a full-blown HMAC). On disk the salt is stored in a ZAP
+ * object in the MOS (DMU_POOL_CHECKSUM_SALT).
+ *
+ * CONTEXT TEMPLATES
+ *
+ * Some hashing algorithms need to perform a substantial amount of
+ * initialization work (e.g. salted checksums above may need to pre-hash
+ * the salt) before being able to process data. Performing this
+ * redundant work for each block would be wasteful, so we instead allow
+ * a checksum algorithm to do the work once (the first time it's used)
+ * and then keep this pre-initialized context as a template inside the
+ * spa_t (spa_cksum_tmpls). If the zio_checksum_info_t contains
+ * non-NULL ci_tmpl_init and ci_tmpl_free callbacks, they are used to
+ * construct and destruct the pre-initialized checksum context. The
+ * pre-initialized context is then reused during each checksum
+ * invocation and passed to the checksum function.
*/
/*ARGSUSED*/
static void
-zio_checksum_off(const void *buf, uint64_t size, zio_cksum_t *zcp)
+abd_checksum_off(abd_t *abd, uint64_t size,
+ const void *ctx_template, zio_cksum_t *zcp)
{
ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0);
}
+/*ARGSUSED*/
+void
+abd_fletcher_2_native(abd_t *abd, uint64_t size,
+ const void *ctx_template, zio_cksum_t *zcp)
+{
+ fletcher_init(zcp);
+ (void) abd_iterate_func(abd, 0, size,
+ fletcher_2_incremental_native, zcp);
+}
+
+/*ARGSUSED*/
+void
+abd_fletcher_2_byteswap(abd_t *abd, uint64_t size,
+ const void *ctx_template, zio_cksum_t *zcp)
+{
+ fletcher_init(zcp);
+ (void) abd_iterate_func(abd, 0, size,
+ fletcher_2_incremental_byteswap, zcp);
+}
+
+static inline void
+abd_fletcher_4_impl(abd_t *abd, uint64_t size, zio_abd_checksum_data_t *acdp)
+{
+ fletcher_4_abd_ops.acf_init(acdp);
+ abd_iterate_func(abd, 0, size, fletcher_4_abd_ops.acf_iter, acdp);
+ fletcher_4_abd_ops.acf_fini(acdp);
+}
+
+/*ARGSUSED*/
+void
+abd_fletcher_4_native(abd_t *abd, uint64_t size,
+ const void *ctx_template, zio_cksum_t *zcp)
+{
+ fletcher_4_ctx_t ctx;
+
+ zio_abd_checksum_data_t acd = {
+ .acd_byteorder = ZIO_CHECKSUM_NATIVE,
+ .acd_zcp = zcp,
+ .acd_ctx = &ctx
+ };
+
+ abd_fletcher_4_impl(abd, size, &acd);
+
+}
+
+/*ARGSUSED*/
+void
+abd_fletcher_4_byteswap(abd_t *abd, uint64_t size,
+ const void *ctx_template, zio_cksum_t *zcp)
+{
+ fletcher_4_ctx_t ctx;
+
+ zio_abd_checksum_data_t acd = {
+ .acd_byteorder = ZIO_CHECKSUM_BYTESWAP,
+ .acd_zcp = zcp,
+ .acd_ctx = &ctx
+ };
+
+ abd_fletcher_4_impl(abd, size, &acd);
+}
+
zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = {
- {{NULL, NULL}, 0, 0, 0, "inherit"},
- {{NULL, NULL}, 0, 0, 0, "on"},
- {{zio_checksum_off, zio_checksum_off}, 0, 0, 0, "off"},
- {{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, 0, "label"},
- {{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, 0, "gang_header"},
- {{fletcher_2_native, fletcher_2_byteswap}, 0, 1, 0, "zilog"},
- {{fletcher_2_native, fletcher_2_byteswap}, 0, 0, 0, "fletcher2"},
- {{fletcher_4_native, fletcher_4_byteswap}, 1, 0, 0, "fletcher4"},
- {{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 0, 1, "sha256"},
- {{fletcher_4_native, fletcher_4_byteswap}, 0, 1, 0, "zilog2"},
+ {{NULL, NULL}, NULL, NULL, 0, "inherit"},
+ {{NULL, NULL}, NULL, NULL, 0, "on"},
+ {{abd_checksum_off, abd_checksum_off},
+ NULL, NULL, 0, "off"},
+ {{abd_checksum_SHA256, abd_checksum_SHA256},
+ NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_EMBEDDED,
+ "label"},
+ {{abd_checksum_SHA256, abd_checksum_SHA256},
+ NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_EMBEDDED,
+ "gang_header"},
+ {{abd_fletcher_2_native, abd_fletcher_2_byteswap},
+ NULL, NULL, ZCHECKSUM_FLAG_EMBEDDED, "zilog"},
+ {{abd_fletcher_2_native, abd_fletcher_2_byteswap},
+ NULL, NULL, 0, "fletcher2"},
+ {{abd_fletcher_4_native, abd_fletcher_4_byteswap},
+ NULL, NULL, ZCHECKSUM_FLAG_METADATA, "fletcher4"},
+ {{abd_checksum_SHA256, abd_checksum_SHA256},
+ NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_DEDUP |
+ ZCHECKSUM_FLAG_NOPWRITE, "sha256"},
+ {{abd_fletcher_4_native, abd_fletcher_4_byteswap},
+ NULL, NULL, ZCHECKSUM_FLAG_EMBEDDED, "zilog2"},
+ {{abd_checksum_off, abd_checksum_off},
+ NULL, NULL, 0, "noparity"},
+ {{abd_checksum_SHA512_native, abd_checksum_SHA512_byteswap},
+ NULL, NULL, ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_DEDUP |
+ ZCHECKSUM_FLAG_NOPWRITE, "sha512"},
+ {{abd_checksum_skein_native, abd_checksum_skein_byteswap},
+ abd_checksum_skein_tmpl_init, abd_checksum_skein_tmpl_free,
+ ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_DEDUP |
+ ZCHECKSUM_FLAG_SALTED | ZCHECKSUM_FLAG_NOPWRITE, "skein"},
+ {{abd_checksum_edonr_native, abd_checksum_edonr_byteswap},
+ abd_checksum_edonr_tmpl_init, abd_checksum_edonr_tmpl_free,
+ ZCHECKSUM_FLAG_METADATA | ZCHECKSUM_FLAG_SALTED |
+ ZCHECKSUM_FLAG_NOPWRITE, "edonr"},
};
+/*
+ * The flag corresponding to the "verify" in dedup=[checksum,]verify
+ * must be cleared first, so callers should use ZIO_CHECKSUM_MASK.
+ */
+spa_feature_t
+zio_checksum_to_feature(enum zio_checksum cksum)
+{
+ VERIFY((cksum & ~ZIO_CHECKSUM_MASK) == 0);
+
+ switch (cksum) {
+ case ZIO_CHECKSUM_SHA512:
+ return (SPA_FEATURE_SHA512);
+ case ZIO_CHECKSUM_SKEIN:
+ return (SPA_FEATURE_SKEIN);
+ case ZIO_CHECKSUM_EDONR:
+ return (SPA_FEATURE_EDONR);
+ default:
+ return (SPA_FEATURE_NONE);
+ }
+}
+
enum zio_checksum
zio_checksum_select(enum zio_checksum child, enum zio_checksum parent)
{
if (child == (ZIO_CHECKSUM_ON | ZIO_CHECKSUM_VERIFY))
return (spa_dedup_checksum(spa) | ZIO_CHECKSUM_VERIFY);
- ASSERT(zio_checksum_table[child & ZIO_CHECKSUM_MASK].ci_dedup ||
+ ASSERT((zio_checksum_table[child & ZIO_CHECKSUM_MASK].ci_flags &
+ ZCHECKSUM_FLAG_DEDUP) ||
(child & ZIO_CHECKSUM_VERIFY) || child == ZIO_CHECKSUM_OFF);
return (child);
* a tuple which is guaranteed to be unique for the life of the pool.
*/
static void
-zio_checksum_gang_verifier(zio_cksum_t *zcp, blkptr_t *bp)
+zio_checksum_gang_verifier(zio_cksum_t *zcp, const blkptr_t *bp)
{
const dva_t *dva = BP_IDENTITY(bp);
uint64_t txg = BP_PHYSICAL_BIRTH(bp);
ZIO_SET_CHECKSUM(zcp, offset, 0, 0, 0);
}
+/*
+ * Calls the template init function of a checksum which supports context
+ * templates and installs the template into the spa_t.
+ */
+static void
+zio_checksum_template_init(enum zio_checksum checksum, spa_t *spa)
+{
+ zio_checksum_info_t *ci = &zio_checksum_table[checksum];
+
+ if (ci->ci_tmpl_init == NULL)
+ return;
+ if (spa->spa_cksum_tmpls[checksum] != NULL)
+ return;
+
+ VERIFY(ci->ci_tmpl_free != NULL);
+ mutex_enter(&spa->spa_cksum_tmpls_lock);
+ if (spa->spa_cksum_tmpls[checksum] == NULL) {
+ spa->spa_cksum_tmpls[checksum] =
+ ci->ci_tmpl_init(&spa->spa_cksum_salt);
+ VERIFY(spa->spa_cksum_tmpls[checksum] != NULL);
+ }
+ mutex_exit(&spa->spa_cksum_tmpls_lock);
+}
+
/*
* Generate the checksum.
*/
void
zio_checksum_compute(zio_t *zio, enum zio_checksum checksum,
- void *data, uint64_t size)
+ abd_t *abd, uint64_t size)
{
+ static const uint64_t zec_magic = ZEC_MAGIC;
blkptr_t *bp = zio->io_bp;
uint64_t offset = zio->io_offset;
zio_checksum_info_t *ci = &zio_checksum_table[checksum];
zio_cksum_t cksum;
+ spa_t *spa = zio->io_spa;
ASSERT((uint_t)checksum < ZIO_CHECKSUM_FUNCTIONS);
ASSERT(ci->ci_func[0] != NULL);
- if (ci->ci_eck) {
- zio_eck_t *eck;
+ zio_checksum_template_init(checksum, spa);
+
+ if (ci->ci_flags & ZCHECKSUM_FLAG_EMBEDDED) {
+ zio_eck_t eck;
+ size_t eck_offset;
if (checksum == ZIO_CHECKSUM_ZILOG2) {
- zil_chain_t *zilc = data;
+ zil_chain_t zilc;
+ abd_copy_to_buf(&zilc, abd, sizeof (zil_chain_t));
- size = P2ROUNDUP_TYPED(zilc->zc_nused, ZIL_MIN_BLKSZ,
+ size = P2ROUNDUP_TYPED(zilc.zc_nused, ZIL_MIN_BLKSZ,
uint64_t);
- eck = &zilc->zc_eck;
+ eck = zilc.zc_eck;
+ eck_offset = offsetof(zil_chain_t, zc_eck);
} else {
- eck = (zio_eck_t *)((char *)data + size) - 1;
+ eck_offset = size - sizeof (zio_eck_t);
+ abd_copy_to_buf_off(&eck, abd, eck_offset,
+ sizeof (zio_eck_t));
}
- if (checksum == ZIO_CHECKSUM_GANG_HEADER)
- zio_checksum_gang_verifier(&eck->zec_cksum, bp);
- else if (checksum == ZIO_CHECKSUM_LABEL)
- zio_checksum_label_verifier(&eck->zec_cksum, offset);
- else
- bp->blk_cksum = eck->zec_cksum;
- eck->zec_magic = ZEC_MAGIC;
- ci->ci_func[0](data, size, &cksum);
- eck->zec_cksum = cksum;
+
+ if (checksum == ZIO_CHECKSUM_GANG_HEADER) {
+ zio_checksum_gang_verifier(&eck.zec_cksum, bp);
+ abd_copy_from_buf_off(abd, &eck.zec_cksum,
+ eck_offset + offsetof(zio_eck_t, zec_cksum),
+ sizeof (zio_cksum_t));
+ } else if (checksum == ZIO_CHECKSUM_LABEL) {
+ zio_checksum_label_verifier(&eck.zec_cksum, offset);
+ abd_copy_from_buf_off(abd, &eck.zec_cksum,
+ eck_offset + offsetof(zio_eck_t, zec_cksum),
+ sizeof (zio_cksum_t));
+ } else {
+ bp->blk_cksum = eck.zec_cksum;
+ }
+
+ abd_copy_from_buf_off(abd, &zec_magic,
+ eck_offset + offsetof(zio_eck_t, zec_magic),
+ sizeof (zec_magic));
+
+ ci->ci_func[0](abd, size, spa->spa_cksum_tmpls[checksum],
+ &cksum);
+
+ abd_copy_from_buf_off(abd, &cksum,
+ eck_offset + offsetof(zio_eck_t, zec_cksum),
+ sizeof (zio_cksum_t));
} else {
- ci->ci_func[0](data, size, &bp->blk_cksum);
+ ci->ci_func[0](abd, size, spa->spa_cksum_tmpls[checksum],
+ &bp->blk_cksum);
}
}
int
-zio_checksum_error(zio_t *zio, zio_bad_cksum_t *info)
+zio_checksum_error_impl(spa_t *spa, const blkptr_t *bp,
+ enum zio_checksum checksum, abd_t *abd, uint64_t size, uint64_t offset,
+ zio_bad_cksum_t *info)
{
- blkptr_t *bp = zio->io_bp;
- uint_t checksum = (bp == NULL ? zio->io_prop.zp_checksum :
- (BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : BP_GET_CHECKSUM(bp)));
- int byteswap;
- int error;
- uint64_t size = (bp == NULL ? zio->io_size :
- (BP_IS_GANG(bp) ? SPA_GANGBLOCKSIZE : BP_GET_PSIZE(bp)));
- uint64_t offset = zio->io_offset;
- void *data = zio->io_data;
zio_checksum_info_t *ci = &zio_checksum_table[checksum];
- zio_cksum_t actual_cksum, expected_cksum, verifier;
+ zio_cksum_t actual_cksum, expected_cksum;
+ zio_eck_t eck;
+ int byteswap;
if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL)
return (SET_ERROR(EINVAL));
- if (ci->ci_eck) {
- zio_eck_t *eck;
+ zio_checksum_template_init(checksum, spa);
+
+ if (ci->ci_flags & ZCHECKSUM_FLAG_EMBEDDED) {
+ zio_cksum_t verifier;
+ size_t eck_offset;
if (checksum == ZIO_CHECKSUM_ZILOG2) {
- zil_chain_t *zilc = data;
+ zil_chain_t zilc;
uint64_t nused;
- eck = &zilc->zc_eck;
- if (eck->zec_magic == ZEC_MAGIC)
- nused = zilc->zc_nused;
- else if (eck->zec_magic == BSWAP_64(ZEC_MAGIC))
- nused = BSWAP_64(zilc->zc_nused);
- else
+ abd_copy_to_buf(&zilc, abd, sizeof (zil_chain_t));
+
+ eck = zilc.zc_eck;
+ eck_offset = offsetof(zil_chain_t, zc_eck) +
+ offsetof(zio_eck_t, zec_cksum);
+
+ if (eck.zec_magic == ZEC_MAGIC) {
+ nused = zilc.zc_nused;
+ } else if (eck.zec_magic == BSWAP_64(ZEC_MAGIC)) {
+ nused = BSWAP_64(zilc.zc_nused);
+ } else {
return (SET_ERROR(ECKSUM));
+ }
- if (nused > size)
+ if (nused > size) {
return (SET_ERROR(ECKSUM));
+ }
size = P2ROUNDUP_TYPED(nused, ZIL_MIN_BLKSZ, uint64_t);
} else {
- eck = (zio_eck_t *)((char *)data + size) - 1;
+ eck_offset = size - sizeof (zio_eck_t);
+ abd_copy_to_buf_off(&eck, abd, eck_offset,
+ sizeof (zio_eck_t));
+ eck_offset += offsetof(zio_eck_t, zec_cksum);
}
if (checksum == ZIO_CHECKSUM_GANG_HEADER)
else
verifier = bp->blk_cksum;
- byteswap = (eck->zec_magic == BSWAP_64(ZEC_MAGIC));
+ byteswap = (eck.zec_magic == BSWAP_64(ZEC_MAGIC));
if (byteswap)
byteswap_uint64_array(&verifier, sizeof (zio_cksum_t));
- expected_cksum = eck->zec_cksum;
- eck->zec_cksum = verifier;
- ci->ci_func[byteswap](data, size, &actual_cksum);
- eck->zec_cksum = expected_cksum;
+ expected_cksum = eck.zec_cksum;
- if (byteswap)
+ abd_copy_from_buf_off(abd, &verifier, eck_offset,
+ sizeof (zio_cksum_t));
+
+ ci->ci_func[byteswap](abd, size,
+ spa->spa_cksum_tmpls[checksum], &actual_cksum);
+
+ abd_copy_from_buf_off(abd, &expected_cksum, eck_offset,
+ sizeof (zio_cksum_t));
+
+ if (byteswap) {
byteswap_uint64_array(&expected_cksum,
sizeof (zio_cksum_t));
+ }
} else {
- ASSERT(!BP_IS_GANG(bp));
byteswap = BP_SHOULD_BYTESWAP(bp);
expected_cksum = bp->blk_cksum;
- ci->ci_func[byteswap](data, size, &actual_cksum);
+ ci->ci_func[byteswap](abd, size,
+ spa->spa_cksum_tmpls[checksum], &actual_cksum);
}
- info->zbc_expected = expected_cksum;
- info->zbc_actual = actual_cksum;
- info->zbc_checksum_name = ci->ci_name;
- info->zbc_byteswapped = byteswap;
- info->zbc_injected = 0;
- info->zbc_has_cksum = 1;
+ if (info != NULL) {
+ info->zbc_expected = expected_cksum;
+ info->zbc_actual = actual_cksum;
+ info->zbc_checksum_name = ci->ci_name;
+ info->zbc_byteswapped = byteswap;
+ info->zbc_injected = 0;
+ info->zbc_has_cksum = 1;
+ }
if (!ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum))
return (SET_ERROR(ECKSUM));
- if (zio_injection_enabled && !zio->io_error &&
- (error = zio_handle_fault_injection(zio, ECKSUM)) != 0) {
+ return (0);
+}
- info->zbc_injected = 1;
- return (error);
+int
+zio_checksum_error(zio_t *zio, zio_bad_cksum_t *info)
+{
+ blkptr_t *bp = zio->io_bp;
+ uint_t checksum = (bp == NULL ? zio->io_prop.zp_checksum :
+ (BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : BP_GET_CHECKSUM(bp)));
+ int error;
+ uint64_t size = (bp == NULL ? zio->io_size :
+ (BP_IS_GANG(bp) ? SPA_GANGBLOCKSIZE : BP_GET_PSIZE(bp)));
+ uint64_t offset = zio->io_offset;
+ abd_t *data = zio->io_abd;
+ spa_t *spa = zio->io_spa;
+
+ error = zio_checksum_error_impl(spa, bp, checksum, data, size,
+ offset, info);
+
+ if (zio_injection_enabled && error == 0 && zio->io_error == 0) {
+ error = zio_handle_fault_injection(zio, ECKSUM);
+ if (error != 0)
+ info->zbc_injected = 1;
}
- return (0);
+ return (error);
+}
+
+/*
+ * Called by a spa_t that's about to be deallocated. This steps through
+ * all of the checksum context templates and deallocates any that were
+ * initialized using the algorithm-specific template init function.
+ */
+void
+zio_checksum_templates_free(spa_t *spa)
+{
+ enum zio_checksum checksum;
+ for (checksum = 0; checksum < ZIO_CHECKSUM_FUNCTIONS;
+ checksum++) {
+ if (spa->spa_cksum_tmpls[checksum] != NULL) {
+ zio_checksum_info_t *ci = &zio_checksum_table[checksum];
+
+ VERIFY(ci->ci_tmpl_free != NULL);
+ ci->ci_tmpl_free(spa->spa_cksum_tmpls[checksum]);
+ spa->spa_cksum_tmpls[checksum] = NULL;
+ }
+ }
}
projects / mirror_zfs-debian.git / blobdiff