Add support for decryption faults in zinject

This patch adds the ability for zinject to trigger decryption
and authentication faults in the ZIO and ARC layers. This
functionality is exposed via the new "decrypt" error type, which
may be provided for "data" object types.

This patch also refactors some of the core encryption / decryption
functions so that they have consistent prototypes, handle errors
consistently, and do not have unused arguments.

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Tom Caputi <[email protected]>
Closes #7474 

1 files changed, 21 insertions, 12 deletions

diff --git a/module/zfs/dsl_crypt.c b/module/zfs/dsl_crypt.c
index 579b32c42..e2067448c 100644
--- a/module/zfs/dsl_crypt.c
+++ b/module/zfs/dsl_crypt.c
@@ -2661,23 +2661,23 @@ error:
  * these fields to populate pabd (the plaintext).
  */
 int
-spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, uint64_t dsobj,
-    const blkptr_t *bp, uint64_t txgid, uint_t datalen, abd_t *pabd,
-    abd_t *cabd, uint8_t *iv, uint8_t *mac, uint8_t *salt, boolean_t *no_crypt)
+spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, const zbookmark_phys_t *zb,
+    dmu_object_type_t ot, boolean_t dedup, boolean_t bswap, uint8_t *salt,
+    uint8_t *iv, uint8_t *mac, uint_t datalen, abd_t *pabd, abd_t *cabd,
+    boolean_t *no_crypt)
 {
 	int ret;
-	dmu_object_type_t ot = BP_GET_TYPE(bp);
 	dsl_crypto_key_t *dck = NULL;
 	uint8_t *plainbuf = NULL, *cipherbuf = NULL;
 
 	ASSERT(spa_feature_is_active(spa, SPA_FEATURE_ENCRYPTION));
-	ASSERT(!BP_IS_EMBEDDED(bp));
-	ASSERT(BP_IS_ENCRYPTED(bp));
 
 	/* look up the key from the spa's keystore */
-	ret = spa_keystore_lookup_key(spa, dsobj, FTAG, &dck);
-	if (ret != 0)
+	ret = spa_keystore_lookup_key(spa, zb->zb_objset, FTAG, &dck);
+	if (ret != 0) {
+		ret = SET_ERROR(EACCES);
 		return (ret);
+	}
 
 	if (encrypt) {
 		plainbuf = abd_borrow_buf_copy(pabd, datalen);
@@ -2696,7 +2696,7 @@ spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, uint64_t dsobj,
 	 * at allocation time in zio_alloc_zil(). On decryption, we simply use
 	 * the provided values.
 	 */
-	if (encrypt && ot != DMU_OT_INTENT_LOG && !BP_GET_DEDUP(bp)) {
+	if (encrypt && ot != DMU_OT_INTENT_LOG && !dedup) {
 		ret = zio_crypt_key_get_salt(&dck->dck_key, salt);
 		if (ret != 0)
 			goto error;
@@ -2704,7 +2704,7 @@ spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, uint64_t dsobj,
 		ret = zio_crypt_generate_iv(iv);
 		if (ret != 0)
 			goto error;
-	} else if (encrypt && BP_GET_DEDUP(bp)) {
+	} else if (encrypt && dedup) {
 		ret = zio_crypt_generate_iv_salt_dedup(&dck->dck_key,
 		    plainbuf, datalen, iv, salt);
 		if (ret != 0)
@@ -2712,8 +2712,17 @@ spa_do_crypt_abd(boolean_t encrypt, spa_t *spa, uint64_t dsobj,
 	}
 
 	/* call lower level function to perform encryption / decryption */
-	ret = zio_do_crypt_data(encrypt, &dck->dck_key, salt, ot, iv, mac,
-	    datalen, BP_SHOULD_BYTESWAP(bp), plainbuf, cipherbuf, no_crypt);
+	ret = zio_do_crypt_data(encrypt, &dck->dck_key, ot, bswap, salt, iv,
+	    mac, datalen, plainbuf, cipherbuf, no_crypt);
+
+	/*
+	 * Handle injected decryption faults. Unfortunately, we cannot inject
+	 * faults for dnode blocks because we might trigger the panic in
+	 * dbuf_prepare_encrypted_dnode_leaf(), which exists because syncing
+	 * context is not prepared to handle malicious decryption failures.
+	 */
+	if (zio_injection_enabled && !encrypt && ot != DMU_OT_DNODE && ret == 0)
+		ret = zio_handle_decrypt_injection(spa, zb, ot, ECKSUM);
 	if (ret != 0)
 		goto error;