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Diffstat (limited to 'sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c')
-rw-r--r--sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c1882
1 files changed, 1882 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c b/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c
new file mode 100644
index 000000000000..d89ef80edd66
--- /dev/null
+++ b/sys/contrib/openzfs/module/os/freebsd/zfs/zio_crypt.c
@@ -0,0 +1,1882 @@
+/*
+ * CDDL HEADER START
+ *
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source. A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright (c) 2017, Datto, Inc. All rights reserved.
+ */
+
+#include <sys/zio_crypt.h>
+#include <sys/dmu.h>
+#include <sys/dmu_objset.h>
+#include <sys/dnode.h>
+#include <sys/fs/zfs.h>
+#include <sys/zio.h>
+#include <sys/zil.h>
+#include <sys/sha2.h>
+#include <sys/hkdf.h>
+
+/*
+ * This file is responsible for handling all of the details of generating
+ * encryption parameters and performing encryption and authentication.
+ *
+ * BLOCK ENCRYPTION PARAMETERS:
+ * Encryption /Authentication Algorithm Suite (crypt):
+ * The encryption algorithm, mode, and key length we are going to use. We
+ * currently support AES in either GCM or CCM modes with 128, 192, and 256 bit
+ * keys. All authentication is currently done with SHA512-HMAC.
+ *
+ * Plaintext:
+ * The unencrypted data that we want to encrypt.
+ *
+ * Initialization Vector (IV):
+ * An initialization vector for the encryption algorithms. This is used to
+ * "tweak" the encryption algorithms so that two blocks of the same data are
+ * encrypted into different ciphertext outputs, thus obfuscating block patterns.
+ * The supported encryption modes (AES-GCM and AES-CCM) require that an IV is
+ * never reused with the same encryption key. This value is stored unencrypted
+ * and must simply be provided to the decryption function. We use a 96 bit IV
+ * (as recommended by NIST) for all block encryption. For non-dedup blocks we
+ * derive the IV randomly. The first 64 bits of the IV are stored in the second
+ * word of DVA[2] and the remaining 32 bits are stored in the upper 32 bits of
+ * blk_fill. This is safe because encrypted blocks can't use the upper 32 bits
+ * of blk_fill. We only encrypt level 0 blocks, which normally have a fill count
+ * of 1. The only exception is for DMU_OT_DNODE objects, where the fill count of
+ * level 0 blocks is the number of allocated dnodes in that block. The on-disk
+ * format supports at most 2^15 slots per L0 dnode block, because the maximum
+ * block size is 16MB (2^24). In either case, for level 0 blocks this number
+ * will still be smaller than UINT32_MAX so it is safe to store the IV in the
+ * top 32 bits of blk_fill, while leaving the bottom 32 bits of the fill count
+ * for the dnode code.
+ *
+ * Master key:
+ * This is the most important secret data of an encrypted dataset. It is used
+ * along with the salt to generate that actual encryption keys via HKDF. We
+ * do not use the master key to directly encrypt any data because there are
+ * theoretical limits on how much data can actually be safely encrypted with
+ * any encryption mode. The master key is stored encrypted on disk with the
+ * user's wrapping key. Its length is determined by the encryption algorithm.
+ * For details on how this is stored see the block comment in dsl_crypt.c
+ *
+ * Salt:
+ * Used as an input to the HKDF function, along with the master key. We use a
+ * 64 bit salt, stored unencrypted in the first word of DVA[2]. Any given salt
+ * can be used for encrypting many blocks, so we cache the current salt and the
+ * associated derived key in zio_crypt_t so we do not need to derive it again
+ * needlessly.
+ *
+ * Encryption Key:
+ * A secret binary key, generated from an HKDF function used to encrypt and
+ * decrypt data.
+ *
+ * Message Authentication Code (MAC)
+ * The MAC is an output of authenticated encryption modes such as AES-GCM and
+ * AES-CCM. Its purpose is to ensure that an attacker cannot modify encrypted
+ * data on disk and return garbage to the application. Effectively, it is a
+ * checksum that can not be reproduced by an attacker. We store the MAC in the
+ * second 128 bits of blk_cksum, leaving the first 128 bits for a truncated
+ * regular checksum of the ciphertext which can be used for scrubbing.
+ *
+ * OBJECT AUTHENTICATION:
+ * Some object types, such as DMU_OT_MASTER_NODE cannot be encrypted because
+ * they contain some info that always needs to be readable. To prevent this
+ * data from being altered, we authenticate this data using SHA512-HMAC. This
+ * will produce a MAC (similar to the one produced via encryption) which can
+ * be used to verify the object was not modified. HMACs do not require key
+ * rotation or IVs, so we can keep up to the full 3 copies of authenticated
+ * data.
+ *
+ * ZIL ENCRYPTION:
+ * ZIL blocks have their bp written to disk ahead of the associated data, so we
+ * cannot store the MAC there as we normally do. For these blocks the MAC is
+ * stored in the embedded checksum within the zil_chain_t header. The salt and
+ * IV are generated for the block on bp allocation instead of at encryption
+ * time. In addition, ZIL blocks have some pieces that must be left in plaintext
+ * for claiming even though all of the sensitive user data still needs to be
+ * encrypted. The function zio_crypt_init_uios_zil() handles parsing which
+ * pieces of the block need to be encrypted. All data that is not encrypted is
+ * authenticated using the AAD mechanisms that the supported encryption modes
+ * provide for. In order to preserve the semantics of the ZIL for encrypted
+ * datasets, the ZIL is not protected at the objset level as described below.
+ *
+ * DNODE ENCRYPTION:
+ * Similarly to ZIL blocks, the core part of each dnode_phys_t needs to be left
+ * in plaintext for scrubbing and claiming, but the bonus buffers might contain
+ * sensitive user data. The function zio_crypt_init_uios_dnode() handles parsing
+ * which which pieces of the block need to be encrypted. For more details about
+ * dnode authentication and encryption, see zio_crypt_init_uios_dnode().
+ *
+ * OBJECT SET AUTHENTICATION:
+ * Up to this point, everything we have encrypted and authenticated has been
+ * at level 0 (or -2 for the ZIL). If we did not do any further work the
+ * on-disk format would be susceptible to attacks that deleted or rearranged
+ * the order of level 0 blocks. Ideally, the cleanest solution would be to
+ * maintain a tree of authentication MACs going up the bp tree. However, this
+ * presents a problem for raw sends. Send files do not send information about
+ * indirect blocks so there would be no convenient way to transfer the MACs and
+ * they cannot be recalculated on the receive side without the master key which
+ * would defeat one of the purposes of raw sends in the first place. Instead,
+ * for the indirect levels of the bp tree, we use a regular SHA512 of the MACs
+ * from the level below. We also include some portable fields from blk_prop such
+ * as the lsize and compression algorithm to prevent the data from being
+ * misinterpreted.
+ *
+ * At the objset level, we maintain 2 separate 256 bit MACs in the
+ * objset_phys_t. The first one is "portable" and is the logical root of the
+ * MAC tree maintained in the metadnode's bps. The second, is "local" and is
+ * used as the root MAC for the user accounting objects, which are also not
+ * transferred via "zfs send". The portable MAC is sent in the DRR_BEGIN payload
+ * of the send file. The useraccounting code ensures that the useraccounting
+ * info is not present upon a receive, so the local MAC can simply be cleared
+ * out at that time. For more info about objset_phys_t authentication, see
+ * zio_crypt_do_objset_hmacs().
+ *
+ * CONSIDERATIONS FOR DEDUP:
+ * In order for dedup to work, blocks that we want to dedup with one another
+ * need to use the same IV and encryption key, so that they will have the same
+ * ciphertext. Normally, one should never reuse an IV with the same encryption
+ * key or else AES-GCM and AES-CCM can both actually leak the plaintext of both
+ * blocks. In this case, however, since we are using the same plaintext as
+ * well all that we end up with is a duplicate of the original ciphertext we
+ * already had. As a result, an attacker with read access to the raw disk will
+ * be able to tell which blocks are the same but this information is given away
+ * by dedup anyway. In order to get the same IVs and encryption keys for
+ * equivalent blocks of data we use an HMAC of the plaintext. We use an HMAC
+ * here so that a reproducible checksum of the plaintext is never available to
+ * the attacker. The HMAC key is kept alongside the master key, encrypted on
+ * disk. The first 64 bits of the HMAC are used in place of the random salt, and
+ * the next 96 bits are used as the IV. As a result of this mechanism, dedup
+ * will only work within a clone family since encrypted dedup requires use of
+ * the same master and HMAC keys.
+ */
+
+/*
+ * After encrypting many blocks with the same key we may start to run up
+ * against the theoretical limits of how much data can securely be encrypted
+ * with a single key using the supported encryption modes. The most obvious
+ * limitation is that our risk of generating 2 equivalent 96 bit IVs increases
+ * the more IVs we generate (which both GCM and CCM modes strictly forbid).
+ * This risk actually grows surprisingly quickly over time according to the
+ * Birthday Problem. With a total IV space of 2^(96 bits), and assuming we have
+ * generated n IVs with a cryptographically secure RNG, the approximate
+ * probability p(n) of a collision is given as:
+ *
+ * p(n) ~= e^(-n*(n-1)/(2*(2^96)))
+ *
+ * [http://www.math.cornell.edu/~mec/2008-2009/TianyiZheng/Birthday.html]
+ *
+ * Assuming that we want to ensure that p(n) never goes over 1 / 1 trillion
+ * we must not write more than 398,065,730 blocks with the same encryption key.
+ * Therefore, we rotate our keys after 400,000,000 blocks have been written by
+ * generating a new random 64 bit salt for our HKDF encryption key generation
+ * function.
+ */
+#define ZFS_KEY_MAX_SALT_USES_DEFAULT 400000000
+#define ZFS_CURRENT_MAX_SALT_USES \
+ (MIN(zfs_key_max_salt_uses, ZFS_KEY_MAX_SALT_USES_DEFAULT))
+unsigned long zfs_key_max_salt_uses = ZFS_KEY_MAX_SALT_USES_DEFAULT;
+
+/*
+ * Set to a nonzero value to cause zio_do_crypt_uio() to fail 1/this many
+ * calls, to test decryption error handling code paths.
+ */
+uint64_t zio_decrypt_fail_fraction = 0;
+
+typedef struct blkptr_auth_buf {
+ uint64_t bab_prop; /* blk_prop - portable mask */
+ uint8_t bab_mac[ZIO_DATA_MAC_LEN]; /* MAC from blk_cksum */
+ uint64_t bab_pad; /* reserved for future use */
+} blkptr_auth_buf_t;
+
+zio_crypt_info_t zio_crypt_table[ZIO_CRYPT_FUNCTIONS] = {
+ {"", ZC_TYPE_NONE, 0, "inherit"},
+ {"", ZC_TYPE_NONE, 0, "on"},
+ {"", ZC_TYPE_NONE, 0, "off"},
+ {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 16, "aes-128-ccm"},
+ {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 24, "aes-192-ccm"},
+ {SUN_CKM_AES_CCM, ZC_TYPE_CCM, 32, "aes-256-ccm"},
+ {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 16, "aes-128-gcm"},
+ {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 24, "aes-192-gcm"},
+ {SUN_CKM_AES_GCM, ZC_TYPE_GCM, 32, "aes-256-gcm"}
+};
+
+static void
+zio_crypt_key_destroy_early(zio_crypt_key_t *key)
+{
+ rw_destroy(&key->zk_salt_lock);
+
+ /* free crypto templates */
+ bzero(&key->zk_session, sizeof (key->zk_session));
+
+ /* zero out sensitive data */
+ bzero(key, sizeof (zio_crypt_key_t));
+}
+
+void
+zio_crypt_key_destroy(zio_crypt_key_t *key)
+{
+
+ freebsd_crypt_freesession(&key->zk_session);
+ zio_crypt_key_destroy_early(key);
+}
+
+int
+zio_crypt_key_init(uint64_t crypt, zio_crypt_key_t *key)
+{
+ int ret;
+ crypto_mechanism_t mech __unused;
+ uint_t keydata_len;
+ zio_crypt_info_t *ci = NULL;
+
+ ASSERT(key != NULL);
+ ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS);
+
+ ci = &zio_crypt_table[crypt];
+ if (ci->ci_crypt_type != ZC_TYPE_GCM &&
+ ci->ci_crypt_type != ZC_TYPE_CCM)
+ return (ENOTSUP);
+
+ keydata_len = zio_crypt_table[crypt].ci_keylen;
+ bzero(key, sizeof (zio_crypt_key_t));
+ rw_init(&key->zk_salt_lock, NULL, RW_DEFAULT, NULL);
+
+ /* fill keydata buffers and salt with random data */
+ ret = random_get_bytes((uint8_t *)&key->zk_guid, sizeof (uint64_t));
+ if (ret != 0)
+ goto error;
+
+ ret = random_get_bytes(key->zk_master_keydata, keydata_len);
+ if (ret != 0)
+ goto error;
+
+ ret = random_get_bytes(key->zk_hmac_keydata, SHA512_HMAC_KEYLEN);
+ if (ret != 0)
+ goto error;
+
+ ret = random_get_bytes(key->zk_salt, ZIO_DATA_SALT_LEN);
+ if (ret != 0)
+ goto error;
+
+ /* derive the current key from the master key */
+ ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0,
+ key->zk_salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata,
+ keydata_len);
+ if (ret != 0)
+ goto error;
+
+ /* initialize keys for the ICP */
+ key->zk_current_key.ck_format = CRYPTO_KEY_RAW;
+ key->zk_current_key.ck_data = key->zk_current_keydata;
+ key->zk_current_key.ck_length = CRYPTO_BYTES2BITS(keydata_len);
+
+ key->zk_hmac_key.ck_format = CRYPTO_KEY_RAW;
+ key->zk_hmac_key.ck_data = &key->zk_hmac_key;
+ key->zk_hmac_key.ck_length = CRYPTO_BYTES2BITS(SHA512_HMAC_KEYLEN);
+
+ ci = &zio_crypt_table[crypt];
+ if (ci->ci_crypt_type != ZC_TYPE_GCM &&
+ ci->ci_crypt_type != ZC_TYPE_CCM)
+ return (ENOTSUP);
+
+ ret = freebsd_crypt_newsession(&key->zk_session, ci,
+ &key->zk_current_key);
+ if (ret)
+ goto error;
+
+ key->zk_crypt = crypt;
+ key->zk_version = ZIO_CRYPT_KEY_CURRENT_VERSION;
+ key->zk_salt_count = 0;
+
+ return (0);
+
+error:
+ zio_crypt_key_destroy_early(key);
+ return (ret);
+}
+
+static int
+zio_crypt_key_change_salt(zio_crypt_key_t *key)
+{
+ int ret = 0;
+ uint8_t salt[ZIO_DATA_SALT_LEN];
+ crypto_mechanism_t mech __unused;
+
+ uint_t keydata_len = zio_crypt_table[key->zk_crypt].ci_keylen;
+
+ /* generate a new salt */
+ ret = random_get_bytes(salt, ZIO_DATA_SALT_LEN);
+ if (ret != 0)
+ goto error;
+
+ rw_enter(&key->zk_salt_lock, RW_WRITER);
+
+ /* someone beat us to the salt rotation, just unlock and return */
+ if (key->zk_salt_count < ZFS_CURRENT_MAX_SALT_USES)
+ goto out_unlock;
+
+ /* derive the current key from the master key and the new salt */
+ ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0,
+ salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata, keydata_len);
+ if (ret != 0)
+ goto out_unlock;
+
+ /* assign the salt and reset the usage count */
+ bcopy(salt, key->zk_salt, ZIO_DATA_SALT_LEN);
+ key->zk_salt_count = 0;
+
+ freebsd_crypt_freesession(&key->zk_session);
+ ret = freebsd_crypt_newsession(&key->zk_session,
+ &zio_crypt_table[key->zk_crypt], &key->zk_current_key);
+ if (ret != 0)
+ goto out_unlock;
+
+ rw_exit(&key->zk_salt_lock);
+
+ return (0);
+
+out_unlock:
+ rw_exit(&key->zk_salt_lock);
+error:
+ return (ret);
+}
+
+/* See comment above zfs_key_max_salt_uses definition for details */
+int
+zio_crypt_key_get_salt(zio_crypt_key_t *key, uint8_t *salt)
+{
+ int ret;
+ boolean_t salt_change;
+
+ rw_enter(&key->zk_salt_lock, RW_READER);
+
+ bcopy(key->zk_salt, salt, ZIO_DATA_SALT_LEN);
+ salt_change = (atomic_inc_64_nv(&key->zk_salt_count) >=
+ ZFS_CURRENT_MAX_SALT_USES);
+
+ rw_exit(&key->zk_salt_lock);
+
+ if (salt_change) {
+ ret = zio_crypt_key_change_salt(key);
+ if (ret != 0)
+ goto error;
+ }
+
+ return (0);
+
+error:
+ return (ret);
+}
+
+void *failed_decrypt_buf;
+int failed_decrypt_size;
+
+/*
+ * This function handles all encryption and decryption in zfs. When
+ * encrypting it expects puio to reference the plaintext and cuio to
+ * reference the ciphertext. cuio must have enough space for the
+ * ciphertext + room for a MAC. datalen should be the length of the
+ * plaintext / ciphertext alone.
+ */
+/*
+ * The implementation for FreeBSD's OpenCrypto.
+ *
+ * The big difference between ICP and FOC is that FOC uses a single
+ * buffer for input and output. This means that (for AES-GCM, the
+ * only one supported right now) the source must be copied into the
+ * destination, and the destination must have the AAD, and the tag/MAC,
+ * already associated with it. (Both implementations can use a uio.)
+ *
+ * Since the auth data is part of the iovec array, all we need to know
+ * is the length: 0 means there's no AAD.
+ *
+ */
+static int
+zio_do_crypt_uio_opencrypto(boolean_t encrypt, freebsd_crypt_session_t *sess,
+ uint64_t crypt, crypto_key_t *key, uint8_t *ivbuf, uint_t datalen,
+ uio_t *uio, uint_t auth_len)
+{
+ zio_crypt_info_t *ci;
+ int ret;
+
+ ci = &zio_crypt_table[crypt];
+ if (ci->ci_crypt_type != ZC_TYPE_GCM &&
+ ci->ci_crypt_type != ZC_TYPE_CCM)
+ return (ENOTSUP);
+
+
+ ret = freebsd_crypt_uio(encrypt, sess, ci, uio, key, ivbuf,
+ datalen, auth_len);
+ if (ret != 0) {
+#ifdef FCRYPTO_DEBUG
+ printf("%s(%d): Returning error %s\n",
+ __FUNCTION__, __LINE__, encrypt ? "EIO" : "ECKSUM");
+#endif
+ ret = SET_ERROR(encrypt ? EIO : ECKSUM);
+ }
+
+ return (ret);
+}
+
+int
+zio_crypt_key_wrap(crypto_key_t *cwkey, zio_crypt_key_t *key, uint8_t *iv,
+ uint8_t *mac, uint8_t *keydata_out, uint8_t *hmac_keydata_out)
+{
+ int ret;
+ uint64_t aad[3];
+ /*
+ * With OpenCrypto in FreeBSD, the same buffer is used for
+ * input and output. Also, the AAD (for AES-GMC at least)
+ * needs to logically go in front.
+ */
+ uio_t cuio;
+ iovec_t iovecs[4];
+ uint64_t crypt = key->zk_crypt;
+ uint_t enc_len, keydata_len, aad_len;
+
+ ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS);
+ ASSERT3U(cwkey->ck_format, ==, CRYPTO_KEY_RAW);
+
+ keydata_len = zio_crypt_table[crypt].ci_keylen;
+
+ /* generate iv for wrapping the master and hmac key */
+ ret = random_get_pseudo_bytes(iv, WRAPPING_IV_LEN);
+ if (ret != 0)
+ goto error;
+
+ /*
+ * Since we only support one buffer, we need to copy
+ * the plain text (source) to the cipher buffer (dest).
+ * We set iovecs[0] -- the authentication data -- below.
+ */
+ bcopy((void*)key->zk_master_keydata, keydata_out, keydata_len);
+ bcopy((void*)key->zk_hmac_keydata, hmac_keydata_out,
+ SHA512_HMAC_KEYLEN);
+ iovecs[1].iov_base = keydata_out;
+ iovecs[1].iov_len = keydata_len;
+ iovecs[2].iov_base = hmac_keydata_out;
+ iovecs[2].iov_len = SHA512_HMAC_KEYLEN;
+ iovecs[3].iov_base = mac;
+ iovecs[3].iov_len = WRAPPING_MAC_LEN;
+
+ /*
+ * Although we don't support writing to the old format, we do
+ * support rewrapping the key so that the user can move and
+ * quarantine datasets on the old format.
+ */
+ if (key->zk_version == 0) {
+ aad_len = sizeof (uint64_t);
+ aad[0] = LE_64(key->zk_guid);
+ } else {
+ ASSERT3U(key->zk_version, ==, ZIO_CRYPT_KEY_CURRENT_VERSION);
+ aad_len = sizeof (uint64_t) * 3;
+ aad[0] = LE_64(key->zk_guid);
+ aad[1] = LE_64(crypt);
+ aad[2] = LE_64(key->zk_version);
+ }
+
+ iovecs[0].iov_base = aad;
+ iovecs[0].iov_len = aad_len;
+ enc_len = zio_crypt_table[crypt].ci_keylen + SHA512_HMAC_KEYLEN;
+
+ cuio.uio_iov = iovecs;
+ cuio.uio_iovcnt = 4;
+ cuio.uio_segflg = UIO_SYSSPACE;
+
+ /* encrypt the keys and store the resulting ciphertext and mac */
+ ret = zio_do_crypt_uio_opencrypto(B_TRUE, NULL, crypt, cwkey,
+ iv, enc_len, &cuio, aad_len);
+ if (ret != 0)
+ goto error;
+
+ return (0);
+
+error:
+ return (ret);
+}
+
+int
+zio_crypt_key_unwrap(crypto_key_t *cwkey, uint64_t crypt, uint64_t version,
+ uint64_t guid, uint8_t *keydata, uint8_t *hmac_keydata, uint8_t *iv,
+ uint8_t *mac, zio_crypt_key_t *key)
+{
+ int ret;
+ uint64_t aad[3];
+ /*
+ * With OpenCrypto in FreeBSD, the same buffer is used for
+ * input and output. Also, the AAD (for AES-GMC at least)
+ * needs to logically go in front.
+ */
+ uio_t cuio;
+ iovec_t iovecs[4];
+ void *src, *dst;
+ uint_t enc_len, keydata_len, aad_len;
+
+ ASSERT3U(crypt, <, ZIO_CRYPT_FUNCTIONS);
+ ASSERT3U(cwkey->ck_format, ==, CRYPTO_KEY_RAW);
+
+ keydata_len = zio_crypt_table[crypt].ci_keylen;
+ rw_init(&key->zk_salt_lock, NULL, RW_DEFAULT, NULL);
+
+ /*
+ * Since we only support one buffer, we need to copy
+ * the encrypted buffer (source) to the plain buffer
+ * (dest). We set iovecs[0] -- the authentication data --
+ * below.
+ */
+ dst = key->zk_master_keydata;
+ src = keydata;
+
+ bcopy(src, dst, keydata_len);
+
+ dst = key->zk_hmac_keydata;
+ src = hmac_keydata;
+ bcopy(src, dst, SHA512_HMAC_KEYLEN);
+
+ iovecs[1].iov_base = key->zk_master_keydata;
+ iovecs[1].iov_len = keydata_len;
+ iovecs[2].iov_base = key->zk_hmac_keydata;
+ iovecs[2].iov_len = SHA512_HMAC_KEYLEN;
+ iovecs[3].iov_base = mac;
+ iovecs[3].iov_len = WRAPPING_MAC_LEN;
+
+ if (version == 0) {
+ aad_len = sizeof (uint64_t);
+ aad[0] = LE_64(guid);
+ } else {
+ ASSERT3U(version, ==, ZIO_CRYPT_KEY_CURRENT_VERSION);
+ aad_len = sizeof (uint64_t) * 3;
+ aad[0] = LE_64(guid);
+ aad[1] = LE_64(crypt);
+ aad[2] = LE_64(version);
+ }
+
+ enc_len = keydata_len + SHA512_HMAC_KEYLEN;
+ iovecs[0].iov_base = aad;
+ iovecs[0].iov_len = aad_len;
+
+ cuio.uio_iov = iovecs;
+ cuio.uio_iovcnt = 4;
+ cuio.uio_segflg = UIO_SYSSPACE;
+
+ /* decrypt the keys and store the result in the output buffers */
+ ret = zio_do_crypt_uio_opencrypto(B_FALSE, NULL, crypt, cwkey,
+ iv, enc_len, &cuio, aad_len);
+
+ if (ret != 0)
+ goto error;
+
+ /* generate a fresh salt */
+ ret = random_get_bytes(key->zk_salt, ZIO_DATA_SALT_LEN);
+ if (ret != 0)
+ goto error;
+
+ /* derive the current key from the master key */
+ ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0,
+ key->zk_salt, ZIO_DATA_SALT_LEN, key->zk_current_keydata,
+ keydata_len);
+ if (ret != 0)
+ goto error;
+
+ /* initialize keys for ICP */
+ key->zk_current_key.ck_format = CRYPTO_KEY_RAW;
+ key->zk_current_key.ck_data = key->zk_current_keydata;
+ key->zk_current_key.ck_length = CRYPTO_BYTES2BITS(keydata_len);
+
+ key->zk_hmac_key.ck_format = CRYPTO_KEY_RAW;
+ key->zk_hmac_key.ck_data = key->zk_hmac_keydata;
+ key->zk_hmac_key.ck_length = CRYPTO_BYTES2BITS(SHA512_HMAC_KEYLEN);
+
+ ret = freebsd_crypt_newsession(&key->zk_session,
+ &zio_crypt_table[crypt], &key->zk_current_key);
+ if (ret != 0)
+ goto error;
+
+ key->zk_crypt = crypt;
+ key->zk_version = version;
+ key->zk_guid = guid;
+ key->zk_salt_count = 0;
+
+ return (0);
+
+error:
+ zio_crypt_key_destroy_early(key);
+ return (ret);
+}
+
+int
+zio_crypt_generate_iv(uint8_t *ivbuf)
+{
+ int ret;
+
+ /* randomly generate the IV */
+ ret = random_get_pseudo_bytes(ivbuf, ZIO_DATA_IV_LEN);
+ if (ret != 0)
+ goto error;
+
+ return (0);
+
+error:
+ bzero(ivbuf, ZIO_DATA_IV_LEN);
+ return (ret);
+}
+
+int
+zio_crypt_do_hmac(zio_crypt_key_t *key, uint8_t *data, uint_t datalen,
+ uint8_t *digestbuf, uint_t digestlen)
+{
+ uint8_t raw_digestbuf[SHA512_DIGEST_LENGTH];
+
+ ASSERT3U(digestlen, <=, SHA512_DIGEST_LENGTH);
+
+ crypto_mac(&key->zk_hmac_key, data, datalen,
+ raw_digestbuf, SHA512_DIGEST_LENGTH);
+
+ bcopy(raw_digestbuf, digestbuf, digestlen);
+
+ return (0);
+}
+
+int
+zio_crypt_generate_iv_salt_dedup(zio_crypt_key_t *key, uint8_t *data,
+ uint_t datalen, uint8_t *ivbuf, uint8_t *salt)
+{
+ int ret;
+ uint8_t digestbuf[SHA512_DIGEST_LENGTH];
+
+ ret = zio_crypt_do_hmac(key, data, datalen,
+ digestbuf, SHA512_DIGEST_LENGTH);
+ if (ret != 0)
+ return (ret);
+
+ bcopy(digestbuf, salt, ZIO_DATA_SALT_LEN);
+ bcopy(digestbuf + ZIO_DATA_SALT_LEN, ivbuf, ZIO_DATA_IV_LEN);
+
+ return (0);
+}
+
+/*
+ * The following functions are used to encode and decode encryption parameters
+ * into blkptr_t and zil_header_t. The ICP wants to use these parameters as
+ * byte strings, which normally means that these strings would not need to deal
+ * with byteswapping at all. However, both blkptr_t and zil_header_t may be
+ * byteswapped by lower layers and so we must "undo" that byteswap here upon
+ * decoding and encoding in a non-native byteorder. These functions require
+ * that the byteorder bit is correct before being called.
+ */
+void
+zio_crypt_encode_params_bp(blkptr_t *bp, uint8_t *salt, uint8_t *iv)
+{
+ uint64_t val64;
+ uint32_t val32;
+
+ ASSERT(BP_IS_ENCRYPTED(bp));
+
+ if (!BP_SHOULD_BYTESWAP(bp)) {
+ bcopy(salt, &bp->blk_dva[2].dva_word[0], sizeof (uint64_t));
+ bcopy(iv, &bp->blk_dva[2].dva_word[1], sizeof (uint64_t));
+ bcopy(iv + sizeof (uint64_t), &val32, sizeof (uint32_t));
+ BP_SET_IV2(bp, val32);
+ } else {
+ bcopy(salt, &val64, sizeof (uint64_t));
+ bp->blk_dva[2].dva_word[0] = BSWAP_64(val64);
+
+ bcopy(iv, &val64, sizeof (uint64_t));
+ bp->blk_dva[2].dva_word[1] = BSWAP_64(val64);
+
+ bcopy(iv + sizeof (uint64_t), &val32, sizeof (uint32_t));
+ BP_SET_IV2(bp, BSWAP_32(val32));
+ }
+}
+
+void
+zio_crypt_decode_params_bp(const blkptr_t *bp, uint8_t *salt, uint8_t *iv)
+{
+ uint64_t val64;
+ uint32_t val32;
+
+ ASSERT(BP_IS_PROTECTED(bp));
+
+ /* for convenience, so callers don't need to check */
+ if (BP_IS_AUTHENTICATED(bp)) {
+ bzero(salt, ZIO_DATA_SALT_LEN);
+ bzero(iv, ZIO_DATA_IV_LEN);
+ return;
+ }
+
+ if (!BP_SHOULD_BYTESWAP(bp)) {
+ bcopy(&bp->blk_dva[2].dva_word[0], salt, sizeof (uint64_t));
+ bcopy(&bp->blk_dva[2].dva_word[1], iv, sizeof (uint64_t));
+
+ val32 = (uint32_t)BP_GET_IV2(bp);
+ bcopy(&val32, iv + sizeof (uint64_t), sizeof (uint32_t));
+ } else {
+ val64 = BSWAP_64(bp->blk_dva[2].dva_word[0]);
+ bcopy(&val64, salt, sizeof (uint64_t));
+
+ val64 = BSWAP_64(bp->blk_dva[2].dva_word[1]);
+ bcopy(&val64, iv, sizeof (uint64_t));
+
+ val32 = BSWAP_32((uint32_t)BP_GET_IV2(bp));
+ bcopy(&val32, iv + sizeof (uint64_t), sizeof (uint32_t));
+ }
+}
+
+void
+zio_crypt_encode_mac_bp(blkptr_t *bp, uint8_t *mac)
+{
+ uint64_t val64;
+
+ ASSERT(BP_USES_CRYPT(bp));
+ ASSERT3U(BP_GET_TYPE(bp), !=, DMU_OT_OBJSET);
+
+ if (!BP_SHOULD_BYTESWAP(bp)) {
+ bcopy(mac, &bp->blk_cksum.zc_word[2], sizeof (uint64_t));
+ bcopy(mac + sizeof (uint64_t), &bp->blk_cksum.zc_word[3],
+ sizeof (uint64_t));
+ } else {
+ bcopy(mac, &val64, sizeof (uint64_t));
+ bp->blk_cksum.zc_word[2] = BSWAP_64(val64);
+
+ bcopy(mac + sizeof (uint64_t), &val64, sizeof (uint64_t));
+ bp->blk_cksum.zc_word[3] = BSWAP_64(val64);
+ }
+}
+
+void
+zio_crypt_decode_mac_bp(const blkptr_t *bp, uint8_t *mac)
+{
+ uint64_t val64;
+
+ ASSERT(BP_USES_CRYPT(bp) || BP_IS_HOLE(bp));
+
+ /* for convenience, so callers don't need to check */
+ if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) {
+ bzero(mac, ZIO_DATA_MAC_LEN);
+ return;
+ }
+
+ if (!BP_SHOULD_BYTESWAP(bp)) {
+ bcopy(&bp->blk_cksum.zc_word[2], mac, sizeof (uint64_t));
+ bcopy(&bp->blk_cksum.zc_word[3], mac + sizeof (uint64_t),
+ sizeof (uint64_t));
+ } else {
+ val64 = BSWAP_64(bp->blk_cksum.zc_word[2]);
+ bcopy(&val64, mac, sizeof (uint64_t));
+
+ val64 = BSWAP_64(bp->blk_cksum.zc_word[3]);
+ bcopy(&val64, mac + sizeof (uint64_t), sizeof (uint64_t));
+ }
+}
+
+void
+zio_crypt_encode_mac_zil(void *data, uint8_t *mac)
+{
+ zil_chain_t *zilc = data;
+
+ bcopy(mac, &zilc->zc_eck.zec_cksum.zc_word[2], sizeof (uint64_t));
+ bcopy(mac + sizeof (uint64_t), &zilc->zc_eck.zec_cksum.zc_word[3],
+ sizeof (uint64_t));
+}
+
+void
+zio_crypt_decode_mac_zil(const void *data, uint8_t *mac)
+{
+ /*
+ * The ZIL MAC is embedded in the block it protects, which will
+ * not have been byteswapped by the time this function has been called.
+ * As a result, we don't need to worry about byteswapping the MAC.
+ */
+ const zil_chain_t *zilc = data;
+
+ bcopy(&zilc->zc_eck.zec_cksum.zc_word[2], mac, sizeof (uint64_t));
+ bcopy(&zilc->zc_eck.zec_cksum.zc_word[3], mac + sizeof (uint64_t),
+ sizeof (uint64_t));
+}
+
+/*
+ * This routine takes a block of dnodes (src_abd) and copies only the bonus
+ * buffers to the same offsets in the dst buffer. datalen should be the size
+ * of both the src_abd and the dst buffer (not just the length of the bonus
+ * buffers).
+ */
+void
+zio_crypt_copy_dnode_bonus(abd_t *src_abd, uint8_t *dst, uint_t datalen)
+{
+ uint_t i, max_dnp = datalen >> DNODE_SHIFT;
+ uint8_t *src;
+ dnode_phys_t *dnp, *sdnp, *ddnp;
+
+ src = abd_borrow_buf_copy(src_abd, datalen);
+
+ sdnp = (dnode_phys_t *)src;
+ ddnp = (dnode_phys_t *)dst;
+
+ for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) {
+ dnp = &sdnp[i];
+ if (dnp->dn_type != DMU_OT_NONE &&
+ DMU_OT_IS_ENCRYPTED(dnp->dn_bonustype) &&
+ dnp->dn_bonuslen != 0) {
+ bcopy(DN_BONUS(dnp), DN_BONUS(&ddnp[i]),
+ DN_MAX_BONUS_LEN(dnp));
+ }
+ }
+
+ abd_return_buf(src_abd, src, datalen);
+}
+
+/*
+ * This function decides what fields from blk_prop are included in
+ * the on-disk various MAC algorithms.
+ */
+static void
+zio_crypt_bp_zero_nonportable_blkprop(blkptr_t *bp, uint64_t version)
+{
+ int avoidlint = SPA_MINBLOCKSIZE;
+ /*
+ * Version 0 did not properly zero out all non-portable fields
+ * as it should have done. We maintain this code so that we can
+ * do read-only imports of pools on this version.
+ */
+ if (version == 0) {
+ BP_SET_DEDUP(bp, 0);
+ BP_SET_CHECKSUM(bp, 0);
+ BP_SET_PSIZE(bp, avoidlint);
+ return;
+ }
+
+ ASSERT3U(version, ==, ZIO_CRYPT_KEY_CURRENT_VERSION);
+
+ /*
+ * The hole_birth feature might set these fields even if this bp
+ * is a hole. We zero them out here to guarantee that raw sends
+ * will function with or without the feature.
+ */
+ if (BP_IS_HOLE(bp)) {
+ bp->blk_prop = 0ULL;
+ return;
+ }
+
+ /*
+ * At L0 we want to verify these fields to ensure that data blocks
+ * can not be reinterpreted. For instance, we do not want an attacker
+ * to trick us into returning raw lz4 compressed data to the user
+ * by modifying the compression bits. At higher levels, we cannot
+ * enforce this policy since raw sends do not convey any information
+ * about indirect blocks, so these values might be different on the
+ * receive side. Fortunately, this does not open any new attack
+ * vectors, since any alterations that can be made to a higher level
+ * bp must still verify the correct order of the layer below it.
+ */
+ if (BP_GET_LEVEL(bp) != 0) {
+ BP_SET_BYTEORDER(bp, 0);
+ BP_SET_COMPRESS(bp, 0);
+
+ /*
+ * psize cannot be set to zero or it will trigger
+ * asserts, but the value doesn't really matter as
+ * long as it is constant.
+ */
+ BP_SET_PSIZE(bp, avoidlint);
+ }
+
+ BP_SET_DEDUP(bp, 0);
+ BP_SET_CHECKSUM(bp, 0);
+}
+
+static void
+zio_crypt_bp_auth_init(uint64_t version, boolean_t should_bswap, blkptr_t *bp,
+ blkptr_auth_buf_t *bab, uint_t *bab_len)
+{
+ blkptr_t tmpbp = *bp;
+
+ if (should_bswap)
+ byteswap_uint64_array(&tmpbp, sizeof (blkptr_t));
+
+ ASSERT(BP_USES_CRYPT(&tmpbp) || BP_IS_HOLE(&tmpbp));
+ ASSERT0(BP_IS_EMBEDDED(&tmpbp));
+
+ zio_crypt_decode_mac_bp(&tmpbp, bab->bab_mac);
+
+ /*
+ * We always MAC blk_prop in LE to ensure portability. This
+ * must be done after decoding the mac, since the endianness
+ * will get zero'd out here.
+ */
+ zio_crypt_bp_zero_nonportable_blkprop(&tmpbp, version);
+ bab->bab_prop = LE_64(tmpbp.blk_prop);
+ bab->bab_pad = 0ULL;
+
+ /* version 0 did not include the padding */
+ *bab_len = sizeof (blkptr_auth_buf_t);
+ if (version == 0)
+ *bab_len -= sizeof (uint64_t);
+}
+
+static int
+zio_crypt_bp_do_hmac_updates(crypto_context_t ctx, uint64_t version,
+ boolean_t should_bswap, blkptr_t *bp)
+{
+ uint_t bab_len;
+ blkptr_auth_buf_t bab;
+
+ zio_crypt_bp_auth_init(version, should_bswap, bp, &bab, &bab_len);
+ crypto_mac_update(ctx, &bab, bab_len);
+
+ return (0);
+}
+
+static void
+zio_crypt_bp_do_indrect_checksum_updates(SHA2_CTX *ctx, uint64_t version,
+ boolean_t should_bswap, blkptr_t *bp)
+{
+ uint_t bab_len;
+ blkptr_auth_buf_t bab;
+
+ zio_crypt_bp_auth_init(version, should_bswap, bp, &bab, &bab_len);
+ SHA2Update(ctx, &bab, bab_len);
+}
+
+static void
+zio_crypt_bp_do_aad_updates(uint8_t **aadp, uint_t *aad_len, uint64_t version,
+ boolean_t should_bswap, blkptr_t *bp)
+{
+ uint_t bab_len;
+ blkptr_auth_buf_t bab;
+
+ zio_crypt_bp_auth_init(version, should_bswap, bp, &bab, &bab_len);
+ bcopy(&bab, *aadp, bab_len);
+ *aadp += bab_len;
+ *aad_len += bab_len;
+}
+
+static int
+zio_crypt_do_dnode_hmac_updates(crypto_context_t ctx, uint64_t version,
+ boolean_t should_bswap, dnode_phys_t *dnp)
+{
+ int ret, i;
+ dnode_phys_t *adnp;
+ boolean_t le_bswap = (should_bswap == ZFS_HOST_BYTEORDER);
+ uint8_t tmp_dncore[offsetof(dnode_phys_t, dn_blkptr)];
+
+ /* authenticate the core dnode (masking out non-portable bits) */
+ bcopy(dnp, tmp_dncore, sizeof (tmp_dncore));
+ adnp = (dnode_phys_t *)tmp_dncore;
+ if (le_bswap) {
+ adnp->dn_datablkszsec = BSWAP_16(adnp->dn_datablkszsec);
+ adnp->dn_bonuslen = BSWAP_16(adnp->dn_bonuslen);
+ adnp->dn_maxblkid = BSWAP_64(adnp->dn_maxblkid);
+ adnp->dn_used = BSWAP_64(adnp->dn_used);
+ }
+ adnp->dn_flags &= DNODE_CRYPT_PORTABLE_FLAGS_MASK;
+ adnp->dn_used = 0;
+
+ crypto_mac_update(ctx, adnp, sizeof (tmp_dncore));
+
+ for (i = 0; i < dnp->dn_nblkptr; i++) {
+ ret = zio_crypt_bp_do_hmac_updates(ctx, version,
+ should_bswap, &dnp->dn_blkptr[i]);
+ if (ret != 0)
+ goto error;
+ }
+
+ if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) {
+ ret = zio_crypt_bp_do_hmac_updates(ctx, version,
+ should_bswap, DN_SPILL_BLKPTR(dnp));
+ if (ret != 0)
+ goto error;
+ }
+
+ return (0);
+
+error:
+ return (ret);
+}
+
+/*
+ * objset_phys_t blocks introduce a number of exceptions to the normal
+ * authentication process. objset_phys_t's contain 2 separate HMACS for
+ * protecting the integrity of their data. The portable_mac protects the
+ * metadnode. This MAC can be sent with a raw send and protects against
+ * reordering of data within the metadnode. The local_mac protects the user
+ * accounting objects which are not sent from one system to another.
+ *
+ * In addition, objset blocks are the only blocks that can be modified and
+ * written to disk without the key loaded under certain circumstances. During
+ * zil_claim() we need to be able to update the zil_header_t to complete
+ * claiming log blocks and during raw receives we need to write out the
+ * portable_mac from the send file. Both of these actions are possible
+ * because these fields are not protected by either MAC so neither one will
+ * need to modify the MACs without the key. However, when the modified blocks
+ * are written out they will be byteswapped into the host machine's native
+ * endianness which will modify fields protected by the MAC. As a result, MAC
+ * calculation for objset blocks works slightly differently from other block
+ * types. Where other block types MAC the data in whatever endianness is
+ * written to disk, objset blocks always MAC little endian version of their
+ * values. In the code, should_bswap is the value from BP_SHOULD_BYTESWAP()
+ * and le_bswap indicates whether a byteswap is needed to get this block
+ * into little endian format.
+ */
+/* ARGSUSED */
+int
+zio_crypt_do_objset_hmacs(zio_crypt_key_t *key, void *data, uint_t datalen,
+ boolean_t should_bswap, uint8_t *portable_mac, uint8_t *local_mac)
+{
+ int ret;
+ struct hmac_ctx hash_ctx;
+ struct hmac_ctx *ctx = &hash_ctx;
+ objset_phys_t *osp = data;
+ uint64_t intval;
+ boolean_t le_bswap = (should_bswap == ZFS_HOST_BYTEORDER);
+ uint8_t raw_portable_mac[SHA512_DIGEST_LENGTH];
+ uint8_t raw_local_mac[SHA512_DIGEST_LENGTH];
+
+
+ /* calculate the portable MAC from the portable fields and metadnode */
+ crypto_mac_init(ctx, &key->zk_hmac_key);
+
+ /* add in the os_type */
+ intval = (le_bswap) ? osp->os_type : BSWAP_64(osp->os_type);
+ crypto_mac_update(ctx, &intval, sizeof (uint64_t));
+
+ /* add in the portable os_flags */
+ intval = osp->os_flags;
+ if (should_bswap)
+ intval = BSWAP_64(intval);
+ intval &= OBJSET_CRYPT_PORTABLE_FLAGS_MASK;
+ /* CONSTCOND */
+ if (!ZFS_HOST_BYTEORDER)
+ intval = BSWAP_64(intval);
+
+ crypto_mac_update(ctx, &intval, sizeof (uint64_t));
+
+ /* add in fields from the metadnode */
+ ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version,
+ should_bswap, &osp->os_meta_dnode);
+ if (ret)
+ goto error;
+
+ crypto_mac_final(ctx, raw_portable_mac, SHA512_DIGEST_LENGTH);
+
+ bcopy(raw_portable_mac, portable_mac, ZIO_OBJSET_MAC_LEN);
+
+ /*
+ * The local MAC protects the user, group and project accounting.
+ * If these objects are not present, the local MAC is zeroed out.
+ */
+ if ((datalen >= OBJSET_PHYS_SIZE_V3 &&
+ osp->os_userused_dnode.dn_type == DMU_OT_NONE &&
+ osp->os_groupused_dnode.dn_type == DMU_OT_NONE &&
+ osp->os_projectused_dnode.dn_type == DMU_OT_NONE) ||
+ (datalen >= OBJSET_PHYS_SIZE_V2 &&
+ osp->os_userused_dnode.dn_type == DMU_OT_NONE &&
+ osp->os_groupused_dnode.dn_type == DMU_OT_NONE) ||
+ (datalen <= OBJSET_PHYS_SIZE_V1)) {
+ bzero(local_mac, ZIO_OBJSET_MAC_LEN);
+ return (0);
+ }
+
+ /* calculate the local MAC from the userused and groupused dnodes */
+ crypto_mac_init(ctx, &key->zk_hmac_key);
+
+ /* add in the non-portable os_flags */
+ intval = osp->os_flags;
+ if (should_bswap)
+ intval = BSWAP_64(intval);
+ intval &= ~OBJSET_CRYPT_PORTABLE_FLAGS_MASK;
+ /* CONSTCOND */
+ if (!ZFS_HOST_BYTEORDER)
+ intval = BSWAP_64(intval);
+
+ crypto_mac_update(ctx, &intval, sizeof (uint64_t));
+
+ /* XXX check dnode type ... */
+ /* add in fields from the user accounting dnodes */
+ if (osp->os_userused_dnode.dn_type != DMU_OT_NONE) {
+ ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version,
+ should_bswap, &osp->os_userused_dnode);
+ if (ret)
+ goto error;
+ }
+
+ if (osp->os_groupused_dnode.dn_type != DMU_OT_NONE) {
+ ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version,
+ should_bswap, &osp->os_groupused_dnode);
+ if (ret)
+ goto error;
+ }
+
+ if (osp->os_projectused_dnode.dn_type != DMU_OT_NONE &&
+ datalen >= OBJSET_PHYS_SIZE_V3) {
+ ret = zio_crypt_do_dnode_hmac_updates(ctx, key->zk_version,
+ should_bswap, &osp->os_projectused_dnode);
+ if (ret)
+ goto error;
+ }
+
+ crypto_mac_final(ctx, raw_local_mac, SHA512_DIGEST_LENGTH);
+
+ bcopy(raw_local_mac, local_mac, ZIO_OBJSET_MAC_LEN);
+
+ return (0);
+
+error:
+ bzero(portable_mac, ZIO_OBJSET_MAC_LEN);
+ bzero(local_mac, ZIO_OBJSET_MAC_LEN);
+ return (ret);
+}
+
+static void
+zio_crypt_destroy_uio(uio_t *uio)
+{
+ if (uio->uio_iov)
+ kmem_free(uio->uio_iov, uio->uio_iovcnt * sizeof (iovec_t));
+}
+
+/*
+ * This function parses an uncompressed indirect block and returns a checksum
+ * of all the portable fields from all of the contained bps. The portable
+ * fields are the MAC and all of the fields from blk_prop except for the dedup,
+ * checksum, and psize bits. For an explanation of the purpose of this, see
+ * the comment block on object set authentication.
+ */
+static int
+zio_crypt_do_indirect_mac_checksum_impl(boolean_t generate, void *buf,
+ uint_t datalen, uint64_t version, boolean_t byteswap, uint8_t *cksum)
+{
+ blkptr_t *bp;
+ int i, epb = datalen >> SPA_BLKPTRSHIFT;
+ SHA2_CTX ctx;
+ uint8_t digestbuf[SHA512_DIGEST_LENGTH];
+
+ /* checksum all of the MACs from the layer below */
+ SHA2Init(SHA512, &ctx);
+ for (i = 0, bp = buf; i < epb; i++, bp++) {
+ zio_crypt_bp_do_indrect_checksum_updates(&ctx, version,
+ byteswap, bp);
+ }
+ SHA2Final(digestbuf, &ctx);
+
+ if (generate) {
+ bcopy(digestbuf, cksum, ZIO_DATA_MAC_LEN);
+ return (0);
+ }
+
+ if (bcmp(digestbuf, cksum, ZIO_DATA_MAC_LEN) != 0) {
+#ifdef FCRYPTO_DEBUG
+ printf("%s(%d): Setting ECKSUM\n", __FUNCTION__, __LINE__);
+#endif
+ return (SET_ERROR(ECKSUM));
+ }
+ return (0);
+}
+
+int
+zio_crypt_do_indirect_mac_checksum(boolean_t generate, void *buf,
+ uint_t datalen, boolean_t byteswap, uint8_t *cksum)
+{
+ int ret;
+
+ /*
+ * Unfortunately, callers of this function will not always have
+ * easy access to the on-disk format version. This info is
+ * normally found in the DSL Crypto Key, but the checksum-of-MACs
+ * is expected to be verifiable even when the key isn't loaded.
+ * Here, instead of doing a ZAP lookup for the version for each
+ * zio, we simply try both existing formats.
+ */
+ ret = zio_crypt_do_indirect_mac_checksum_impl(generate, buf,
+ datalen, ZIO_CRYPT_KEY_CURRENT_VERSION, byteswap, cksum);
+ if (ret == ECKSUM) {
+ ASSERT(!generate);
+ ret = zio_crypt_do_indirect_mac_checksum_impl(generate,
+ buf, datalen, 0, byteswap, cksum);
+ }
+
+ return (ret);
+}
+
+int
+zio_crypt_do_indirect_mac_checksum_abd(boolean_t generate, abd_t *abd,
+ uint_t datalen, boolean_t byteswap, uint8_t *cksum)
+{
+ int ret;
+ void *buf;
+
+ buf = abd_borrow_buf_copy(abd, datalen);
+ ret = zio_crypt_do_indirect_mac_checksum(generate, buf, datalen,
+ byteswap, cksum);
+ abd_return_buf(abd, buf, datalen);
+
+ return (ret);
+}
+
+/*
+ * Special case handling routine for encrypting / decrypting ZIL blocks.
+ * We do not check for the older ZIL chain because the encryption feature
+ * was not available before the newer ZIL chain was introduced. The goal
+ * here is to encrypt everything except the blkptr_t of a lr_write_t and
+ * the zil_chain_t header. Everything that is not encrypted is authenticated.
+ */
+/*
+ * The OpenCrypto used in FreeBSD does not use separate source and
+ * destination buffers; instead, the same buffer is used. Further, to
+ * accommodate some of the drivers, the authbuf needs to be logically before
+ * the data. This means that we need to copy the source to the destination,
+ * and set up an extra iovec_t at the beginning to handle the authbuf.
+ * It also means we'll only return one uio_t, which we do via the clumsy
+ * ifdef in the function declaration.
+ */
+
+/* ARGSUSED */
+static int
+zio_crypt_init_uios_zil(boolean_t encrypt, uint8_t *plainbuf,
+ uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap, uio_t *puio,
+ uio_t *out_uio, uint_t *enc_len, uint8_t **authbuf, uint_t *auth_len,
+ boolean_t *no_crypt)
+{
+ int ret;
+ uint64_t txtype, lr_len;
+ uint_t nr_src, nr_dst, crypt_len;
+ uint_t aad_len = 0, nr_iovecs = 0, total_len = 0;
+ iovec_t *src_iovecs = NULL, *dst_iovecs = NULL;
+ uint8_t *src, *dst, *slrp, *dlrp, *blkend, *aadp;
+ zil_chain_t *zilc;
+ lr_t *lr;
+ uint8_t *aadbuf = zio_buf_alloc(datalen);
+
+ /* cipherbuf always needs an extra iovec for the MAC */
+ if (encrypt) {
+ src = plainbuf;
+ dst = cipherbuf;
+ nr_src = 0;
+ nr_dst = 1;
+ } else {
+ src = cipherbuf;
+ dst = plainbuf;
+ nr_src = 1;
+ nr_dst = 0;
+ }
+
+ /*
+ * We need at least two iovecs -- one for the AAD,
+ * one for the MAC.
+ */
+ bcopy(src, dst, datalen);
+ nr_dst = 2;
+
+ /* find the start and end record of the log block */
+ zilc = (zil_chain_t *)src;
+ slrp = src + sizeof (zil_chain_t);
+ aadp = aadbuf;
+ blkend = src + ((byteswap) ? BSWAP_64(zilc->zc_nused) : zilc->zc_nused);
+
+ /* calculate the number of encrypted iovecs we will need */
+ for (; slrp < blkend; slrp += lr_len) {
+ lr = (lr_t *)slrp;
+
+ if (!byteswap) {
+ txtype = lr->lrc_txtype;
+ lr_len = lr->lrc_reclen;
+ } else {
+ txtype = BSWAP_64(lr->lrc_txtype);
+ lr_len = BSWAP_64(lr->lrc_reclen);
+ }
+
+ nr_iovecs++;
+ if (txtype == TX_WRITE && lr_len != sizeof (lr_write_t))
+ nr_iovecs++;
+ }
+
+ nr_src = 0;
+ nr_dst += nr_iovecs;
+
+ /* allocate the iovec arrays */
+ if (nr_src != 0) {
+ src_iovecs = kmem_alloc(nr_src * sizeof (iovec_t), KM_SLEEP);
+ if (src_iovecs == NULL) {
+ ret = SET_ERROR(ENOMEM);
+ goto error;
+ }
+ bzero(src_iovecs, nr_src * sizeof (iovec_t));
+ }
+
+ if (nr_dst != 0) {
+ dst_iovecs = kmem_alloc(nr_dst * sizeof (iovec_t), KM_SLEEP);
+ if (dst_iovecs == NULL) {
+ ret = SET_ERROR(ENOMEM);
+ goto error;
+ }
+ bzero(dst_iovecs, nr_dst * sizeof (iovec_t));
+ }
+
+ /*
+ * Copy the plain zil header over and authenticate everything except
+ * the checksum that will store our MAC. If we are writing the data
+ * the embedded checksum will not have been calculated yet, so we don't
+ * authenticate that.
+ */
+ bcopy(src, dst, sizeof (zil_chain_t));
+ bcopy(src, aadp, sizeof (zil_chain_t) - sizeof (zio_eck_t));
+ aadp += sizeof (zil_chain_t) - sizeof (zio_eck_t);
+ aad_len += sizeof (zil_chain_t) - sizeof (zio_eck_t);
+
+ /* loop over records again, filling in iovecs */
+ /* The first one will contain the authbuf */
+ nr_iovecs = 1;
+
+ slrp = src + sizeof (zil_chain_t);
+ dlrp = dst + sizeof (zil_chain_t);
+
+ for (; slrp < blkend; slrp += lr_len, dlrp += lr_len) {
+ lr = (lr_t *)slrp;
+
+ if (!byteswap) {
+ txtype = lr->lrc_txtype;
+ lr_len = lr->lrc_reclen;
+ } else {
+ txtype = BSWAP_64(lr->lrc_txtype);
+ lr_len = BSWAP_64(lr->lrc_reclen);
+ }
+
+ /* copy the common lr_t */
+ bcopy(slrp, dlrp, sizeof (lr_t));
+ bcopy(slrp, aadp, sizeof (lr_t));
+ aadp += sizeof (lr_t);
+ aad_len += sizeof (lr_t);
+
+ ASSERT3P(dst_iovecs, !=, NULL);
+
+ /*
+ * If this is a TX_WRITE record we want to encrypt everything
+ * except the bp if exists. If the bp does exist we want to
+ * authenticate it.
+ */
+ if (txtype == TX_WRITE) {
+ crypt_len = sizeof (lr_write_t) -
+ sizeof (lr_t) - sizeof (blkptr_t);
+ dst_iovecs[nr_iovecs].iov_base = (char *)dlrp +
+ sizeof (lr_t);
+ dst_iovecs[nr_iovecs].iov_len = crypt_len;
+
+ /* copy the bp now since it will not be encrypted */
+ bcopy(slrp + sizeof (lr_write_t) - sizeof (blkptr_t),
+ dlrp + sizeof (lr_write_t) - sizeof (blkptr_t),
+ sizeof (blkptr_t));
+ bcopy(slrp + sizeof (lr_write_t) - sizeof (blkptr_t),
+ aadp, sizeof (blkptr_t));
+ aadp += sizeof (blkptr_t);
+ aad_len += sizeof (blkptr_t);
+ nr_iovecs++;
+ total_len += crypt_len;
+
+ if (lr_len != sizeof (lr_write_t)) {
+ crypt_len = lr_len - sizeof (lr_write_t);
+ dst_iovecs[nr_iovecs].iov_base = (char *)
+ dlrp + sizeof (lr_write_t);
+ dst_iovecs[nr_iovecs].iov_len = crypt_len;
+ nr_iovecs++;
+ total_len += crypt_len;
+ }
+ } else {
+ crypt_len = lr_len - sizeof (lr_t);
+ dst_iovecs[nr_iovecs].iov_base = (char *)dlrp +
+ sizeof (lr_t);
+ dst_iovecs[nr_iovecs].iov_len = crypt_len;
+ nr_iovecs++;
+ total_len += crypt_len;
+ }
+ }
+
+ *no_crypt = (nr_iovecs == 0);
+ *enc_len = total_len;
+ *authbuf = aadbuf;
+ *auth_len = aad_len;
+ dst_iovecs[0].iov_base = aadbuf;
+ dst_iovecs[0].iov_len = aad_len;
+
+ out_uio->uio_iov = dst_iovecs;
+ out_uio->uio_iovcnt = nr_dst;
+
+ return (0);
+
+error:
+ zio_buf_free(aadbuf, datalen);
+ if (src_iovecs != NULL)
+ kmem_free(src_iovecs, nr_src * sizeof (iovec_t));
+ if (dst_iovecs != NULL)
+ kmem_free(dst_iovecs, nr_dst * sizeof (iovec_t));
+
+ *enc_len = 0;
+ *authbuf = NULL;
+ *auth_len = 0;
+ *no_crypt = B_FALSE;
+ puio->uio_iov = NULL;
+ puio->uio_iovcnt = 0;
+ out_uio->uio_iov = NULL;
+ out_uio->uio_iovcnt = 0;
+
+ return (ret);
+}
+
+/*
+ * Special case handling routine for encrypting / decrypting dnode blocks.
+ */
+static int
+zio_crypt_init_uios_dnode(boolean_t encrypt, uint64_t version,
+ uint8_t *plainbuf, uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap,
+ uio_t *puio, uio_t *out_uio, uint_t *enc_len, uint8_t **authbuf,
+ uint_t *auth_len, boolean_t *no_crypt)
+{
+ int ret;
+ uint_t nr_src, nr_dst, crypt_len;
+ uint_t aad_len = 0, nr_iovecs = 0, total_len = 0;
+ uint_t i, j, max_dnp = datalen >> DNODE_SHIFT;
+ iovec_t *src_iovecs = NULL, *dst_iovecs = NULL;
+ uint8_t *src, *dst, *aadp;
+ dnode_phys_t *dnp, *adnp, *sdnp, *ddnp;
+ uint8_t *aadbuf = zio_buf_alloc(datalen);
+
+ if (encrypt) {
+ src = plainbuf;
+ dst = cipherbuf;
+ nr_src = 0;
+ nr_dst = 1;
+ } else {
+ src = cipherbuf;
+ dst = plainbuf;
+ nr_src = 1;
+ nr_dst = 0;
+ }
+
+ bcopy(src, dst, datalen);
+ nr_dst = 2;
+
+ sdnp = (dnode_phys_t *)src;
+ ddnp = (dnode_phys_t *)dst;
+ aadp = aadbuf;
+
+ /*
+ * Count the number of iovecs we will need to do the encryption by
+ * counting the number of bonus buffers that need to be encrypted.
+ */
+ for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) {
+ /*
+ * This block may still be byteswapped. However, all of the
+ * values we use are either uint8_t's (for which byteswapping
+ * is a noop) or a * != 0 check, which will work regardless
+ * of whether or not we byteswap.
+ */
+ if (sdnp[i].dn_type != DMU_OT_NONE &&
+ DMU_OT_IS_ENCRYPTED(sdnp[i].dn_bonustype) &&
+ sdnp[i].dn_bonuslen != 0) {
+ nr_iovecs++;
+ }
+ }
+
+ nr_src = 0;
+ nr_dst += nr_iovecs;
+
+ if (nr_src != 0) {
+ src_iovecs = kmem_alloc(nr_src * sizeof (iovec_t), KM_SLEEP);
+ if (src_iovecs == NULL) {
+ ret = SET_ERROR(ENOMEM);
+ goto error;
+ }
+ bzero(src_iovecs, nr_src * sizeof (iovec_t));
+ }
+
+ if (nr_dst != 0) {
+ dst_iovecs = kmem_alloc(nr_dst * sizeof (iovec_t), KM_SLEEP);
+ if (dst_iovecs == NULL) {
+ ret = SET_ERROR(ENOMEM);
+ goto error;
+ }
+ bzero(dst_iovecs, nr_dst * sizeof (iovec_t));
+ }
+
+ nr_iovecs = 1;
+
+ /*
+ * Iterate through the dnodes again, this time filling in the uios
+ * we allocated earlier. We also concatenate any data we want to
+ * authenticate onto aadbuf.
+ */
+ for (i = 0; i < max_dnp; i += sdnp[i].dn_extra_slots + 1) {
+ dnp = &sdnp[i];
+
+ /* copy over the core fields and blkptrs (kept as plaintext) */
+ bcopy(dnp, &ddnp[i], (uint8_t *)DN_BONUS(dnp) - (uint8_t *)dnp);
+
+ if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) {
+ bcopy(DN_SPILL_BLKPTR(dnp), DN_SPILL_BLKPTR(&ddnp[i]),
+ sizeof (blkptr_t));
+ }
+
+ /*
+ * Handle authenticated data. We authenticate everything in
+ * the dnode that can be brought over when we do a raw send.
+ * This includes all of the core fields as well as the MACs
+ * stored in the bp checksums and all of the portable bits
+ * from blk_prop. We include the dnode padding here in case it
+ * ever gets used in the future. Some dn_flags and dn_used are
+ * not portable so we mask those out values out of the
+ * authenticated data.
+ */
+ crypt_len = offsetof(dnode_phys_t, dn_blkptr);
+ bcopy(dnp, aadp, crypt_len);
+ adnp = (dnode_phys_t *)aadp;
+ adnp->dn_flags &= DNODE_CRYPT_PORTABLE_FLAGS_MASK;
+ adnp->dn_used = 0;
+ aadp += crypt_len;
+ aad_len += crypt_len;
+
+ for (j = 0; j < dnp->dn_nblkptr; j++) {
+ zio_crypt_bp_do_aad_updates(&aadp, &aad_len,
+ version, byteswap, &dnp->dn_blkptr[j]);
+ }
+
+ if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) {
+ zio_crypt_bp_do_aad_updates(&aadp, &aad_len,
+ version, byteswap, DN_SPILL_BLKPTR(dnp));
+ }
+
+ /*
+ * If this bonus buffer needs to be encrypted, we prepare an
+ * iovec_t. The encryption / decryption functions will fill
+ * this in for us with the encrypted or decrypted data.
+ * Otherwise we add the bonus buffer to the authenticated
+ * data buffer and copy it over to the destination. The
+ * encrypted iovec extends to DN_MAX_BONUS_LEN(dnp) so that
+ * we can guarantee alignment with the AES block size
+ * (128 bits).
+ */
+ crypt_len = DN_MAX_BONUS_LEN(dnp);
+ if (dnp->dn_type != DMU_OT_NONE &&
+ DMU_OT_IS_ENCRYPTED(dnp->dn_bonustype) &&
+ dnp->dn_bonuslen != 0) {
+ ASSERT3U(nr_iovecs, <, nr_dst);
+ ASSERT3P(dst_iovecs, !=, NULL);
+ dst_iovecs[nr_iovecs].iov_base = DN_BONUS(&ddnp[i]);
+ dst_iovecs[nr_iovecs].iov_len = crypt_len;
+
+ nr_iovecs++;
+ total_len += crypt_len;
+ } else {
+ bcopy(DN_BONUS(dnp), DN_BONUS(&ddnp[i]), crypt_len);
+ bcopy(DN_BONUS(dnp), aadp, crypt_len);
+ aadp += crypt_len;
+ aad_len += crypt_len;
+ }
+ }
+
+ *no_crypt = (nr_iovecs == 0);
+ *enc_len = total_len;
+ *authbuf = aadbuf;
+ *auth_len = aad_len;
+
+ dst_iovecs[0].iov_base = aadbuf;
+ dst_iovecs[0].iov_len = aad_len;
+ out_uio->uio_iov = dst_iovecs;
+ out_uio->uio_iovcnt = nr_dst;
+
+ return (0);
+
+error:
+ zio_buf_free(aadbuf, datalen);
+ if (src_iovecs != NULL)
+ kmem_free(src_iovecs, nr_src * sizeof (iovec_t));
+ if (dst_iovecs != NULL)
+ kmem_free(dst_iovecs, nr_dst * sizeof (iovec_t));
+
+ *enc_len = 0;
+ *authbuf = NULL;
+ *auth_len = 0;
+ *no_crypt = B_FALSE;
+ out_uio->uio_iov = NULL;
+ out_uio->uio_iovcnt = 0;
+
+ return (ret);
+}
+
+/* ARGSUSED */
+static int
+zio_crypt_init_uios_normal(boolean_t encrypt, uint8_t *plainbuf,
+ uint8_t *cipherbuf, uint_t datalen, uio_t *puio, uio_t *out_uio,
+ uint_t *enc_len)
+{
+ int ret;
+ uint_t nr_plain = 1, nr_cipher = 2;
+ iovec_t *plain_iovecs = NULL, *cipher_iovecs = NULL;
+ void *src, *dst;
+
+ cipher_iovecs = kmem_alloc(nr_cipher * sizeof (iovec_t),
+ KM_SLEEP);
+ if (!cipher_iovecs) {
+ ret = SET_ERROR(ENOMEM);
+ goto error;
+ }
+ bzero(cipher_iovecs, nr_cipher * sizeof (iovec_t));
+
+ if (encrypt) {
+ src = plainbuf;
+ dst = cipherbuf;
+ } else {
+ src = cipherbuf;
+ dst = plainbuf;
+ }
+ bcopy(src, dst, datalen);
+ cipher_iovecs[0].iov_base = dst;
+ cipher_iovecs[0].iov_len = datalen;
+
+ *enc_len = datalen;
+ out_uio->uio_iov = cipher_iovecs;
+ out_uio->uio_iovcnt = nr_cipher;
+
+ return (0);
+
+error:
+ if (plain_iovecs != NULL)
+ kmem_free(plain_iovecs, nr_plain * sizeof (iovec_t));
+ if (cipher_iovecs != NULL)
+ kmem_free(cipher_iovecs, nr_cipher * sizeof (iovec_t));
+
+ *enc_len = 0;
+ out_uio->uio_iov = NULL;
+ out_uio->uio_iovcnt = 0;
+
+ return (ret);
+}
+
+/*
+ * This function builds up the plaintext (puio) and ciphertext (cuio) uios so
+ * that they can be used for encryption and decryption by zio_do_crypt_uio().
+ * Most blocks will use zio_crypt_init_uios_normal(), with ZIL and dnode blocks
+ * requiring special handling to parse out pieces that are to be encrypted. The
+ * authbuf is used by these special cases to store additional authenticated
+ * data (AAD) for the encryption modes.
+ */
+static int
+zio_crypt_init_uios(boolean_t encrypt, uint64_t version, dmu_object_type_t ot,
+ uint8_t *plainbuf, uint8_t *cipherbuf, uint_t datalen, boolean_t byteswap,
+ uint8_t *mac, uio_t *puio, uio_t *cuio, uint_t *enc_len, uint8_t **authbuf,
+ uint_t *auth_len, boolean_t *no_crypt)
+{
+ int ret;
+ iovec_t *mac_iov;
+
+ ASSERT(DMU_OT_IS_ENCRYPTED(ot) || ot == DMU_OT_NONE);
+
+ /* route to handler */
+ switch (ot) {
+ case DMU_OT_INTENT_LOG:
+ ret = zio_crypt_init_uios_zil(encrypt, plainbuf, cipherbuf,
+ datalen, byteswap, puio, cuio, enc_len, authbuf, auth_len,
+ no_crypt);
+ break;
+ case DMU_OT_DNODE:
+ ret = zio_crypt_init_uios_dnode(encrypt, version, plainbuf,
+ cipherbuf, datalen, byteswap, puio, cuio, enc_len, authbuf,
+ auth_len, no_crypt);
+ break;
+ default:
+ ret = zio_crypt_init_uios_normal(encrypt, plainbuf, cipherbuf,
+ datalen, puio, cuio, enc_len);
+ *authbuf = NULL;
+ *auth_len = 0;
+ *no_crypt = B_FALSE;
+ break;
+ }
+
+ if (ret != 0)
+ goto error;
+
+ /* populate the uios */
+ cuio->uio_segflg = UIO_SYSSPACE;
+
+ mac_iov = ((iovec_t *)&cuio->uio_iov[cuio->uio_iovcnt - 1]);
+ mac_iov->iov_base = (void *)mac;
+ mac_iov->iov_len = ZIO_DATA_MAC_LEN;
+
+ return (0);
+
+error:
+ return (ret);
+}
+
+void *failed_decrypt_buf;
+int faile_decrypt_size;
+
+/*
+ * Primary encryption / decryption entrypoint for zio data.
+ */
+int
+zio_do_crypt_data(boolean_t encrypt, zio_crypt_key_t *key,
+ dmu_object_type_t ot, boolean_t byteswap, uint8_t *salt, uint8_t *iv,
+ uint8_t *mac, uint_t datalen, uint8_t *plainbuf, uint8_t *cipherbuf,
+ boolean_t *no_crypt)
+{
+ int ret;
+ boolean_t locked = B_FALSE;
+ uint64_t crypt = key->zk_crypt;
+ uint_t keydata_len = zio_crypt_table[crypt].ci_keylen;
+ uint_t enc_len, auth_len;
+ uio_t puio, cuio;
+ uint8_t enc_keydata[MASTER_KEY_MAX_LEN];
+ crypto_key_t tmp_ckey, *ckey = NULL;
+ freebsd_crypt_session_t *tmpl = NULL;
+ uint8_t *authbuf = NULL;
+
+ bzero(&puio, sizeof (uio_t));
+ bzero(&cuio, sizeof (uio_t));
+
+#ifdef FCRYPTO_DEBUG
+ printf("%s(%s, %p, %p, %d, %p, %p, %u, %s, %p, %p, %p)\n",
+ __FUNCTION__,
+ encrypt ? "encrypt" : "decrypt",
+ key, salt, ot, iv, mac, datalen,
+ byteswap ? "byteswap" : "native_endian", plainbuf,
+ cipherbuf, no_crypt);
+
+ printf("\tkey = {");
+ for (int i = 0; i < key->zk_current_key.ck_length/8; i++)
+ printf("%02x ", ((uint8_t *)key->zk_current_key.ck_data)[i]);
+ printf("}\n");
+#endif
+ /* create uios for encryption */
+ ret = zio_crypt_init_uios(encrypt, key->zk_version, ot, plainbuf,
+ cipherbuf, datalen, byteswap, mac, &puio, &cuio, &enc_len,
+ &authbuf, &auth_len, no_crypt);
+ if (ret != 0)
+ return (ret);
+
+ /*
+ * If the needed key is the current one, just use it. Otherwise we
+ * need to generate a temporary one from the given salt + master key.
+ * If we are encrypting, we must return a copy of the current salt
+ * so that it can be stored in the blkptr_t.
+ */
+ rw_enter(&key->zk_salt_lock, RW_READER);
+ locked = B_TRUE;
+
+ if (bcmp(salt, key->zk_salt, ZIO_DATA_SALT_LEN) == 0) {
+ ckey = &key->zk_current_key;
+ tmpl = &key->zk_session;
+ } else {
+ rw_exit(&key->zk_salt_lock);
+ locked = B_FALSE;
+
+ ret = hkdf_sha512(key->zk_master_keydata, keydata_len, NULL, 0,
+ salt, ZIO_DATA_SALT_LEN, enc_keydata, keydata_len);
+ if (ret != 0)
+ goto error;
+ tmp_ckey.ck_format = CRYPTO_KEY_RAW;
+ tmp_ckey.ck_data = enc_keydata;
+ tmp_ckey.ck_length = CRYPTO_BYTES2BITS(keydata_len);
+
+ ckey = &tmp_ckey;
+ tmpl = NULL;
+ }
+
+ /* perform the encryption / decryption */
+ ret = zio_do_crypt_uio_opencrypto(encrypt, tmpl, key->zk_crypt,
+ ckey, iv, enc_len, &cuio, auth_len);
+ if (ret != 0)
+ goto error;
+ if (locked) {
+ rw_exit(&key->zk_salt_lock);
+ locked = B_FALSE;
+ }
+
+ if (authbuf != NULL)
+ zio_buf_free(authbuf, datalen);
+ if (ckey == &tmp_ckey)
+ bzero(enc_keydata, keydata_len);
+ zio_crypt_destroy_uio(&puio);
+ zio_crypt_destroy_uio(&cuio);
+
+ return (0);
+
+error:
+ if (!encrypt) {
+ if (failed_decrypt_buf != NULL)
+ kmem_free(failed_decrypt_buf, failed_decrypt_size);
+ failed_decrypt_buf = kmem_alloc(datalen, KM_SLEEP);
+ failed_decrypt_size = datalen;
+ bcopy(cipherbuf, failed_decrypt_buf, datalen);
+ }
+ if (locked)
+ rw_exit(&key->zk_salt_lock);
+ if (authbuf != NULL)
+ zio_buf_free(authbuf, datalen);
+ if (ckey == &tmp_ckey)
+ bzero(enc_keydata, keydata_len);
+ zio_crypt_destroy_uio(&puio);
+ zio_crypt_destroy_uio(&cuio);
+ return (SET_ERROR(ret));
+}
+
+/*
+ * Simple wrapper around zio_do_crypt_data() to work with abd's instead of
+ * linear buffers.
+ */
+int
+zio_do_crypt_abd(boolean_t encrypt, zio_crypt_key_t *key, dmu_object_type_t ot,
+ boolean_t byteswap, uint8_t *salt, uint8_t *iv, uint8_t *mac,
+ uint_t datalen, abd_t *pabd, abd_t *cabd, boolean_t *no_crypt)
+{
+ int ret;
+ void *ptmp, *ctmp;
+
+ if (encrypt) {
+ ptmp = abd_borrow_buf_copy(pabd, datalen);
+ ctmp = abd_borrow_buf(cabd, datalen);
+ } else {
+ ptmp = abd_borrow_buf(pabd, datalen);
+ ctmp = abd_borrow_buf_copy(cabd, datalen);
+ }
+
+ ret = zio_do_crypt_data(encrypt, key, ot, byteswap, salt, iv, mac,
+ datalen, ptmp, ctmp, no_crypt);
+ if (ret != 0)
+ goto error;
+
+ if (encrypt) {
+ abd_return_buf(pabd, ptmp, datalen);
+ abd_return_buf_copy(cabd, ctmp, datalen);
+ } else {
+ abd_return_buf_copy(pabd, ptmp, datalen);
+ abd_return_buf(cabd, ctmp, datalen);
+ }
+
+ return (0);
+
+error:
+ if (encrypt) {
+ abd_return_buf(pabd, ptmp, datalen);
+ abd_return_buf_copy(cabd, ctmp, datalen);
+ } else {
+ abd_return_buf_copy(pabd, ptmp, datalen);
+ abd_return_buf(cabd, ctmp, datalen);
+ }
+
+ return (SET_ERROR(ret));
+}
+
+#if defined(_KERNEL) && defined(HAVE_SPL)
+/* BEGIN CSTYLED */
+module_param(zfs_key_max_salt_uses, ulong, 0644);
+MODULE_PARM_DESC(zfs_key_max_salt_uses, "Max number of times a salt value "
+ "can be used for generating encryption keys before it is rotated");
+/* END CSTYLED */
+#endif