diff -rupN cryptsetup-2.3.3.orig/tests/api-test-2.c cryptsetup-2.3.3/tests/api-test-2.c
--- cryptsetup-2.3.3.orig/tests/api-test-2.c	2021-02-17 19:48:46.483519319 +0100
+++ cryptsetup-2.3.3/tests/api-test-2.c	2021-02-17 19:49:10.527493909 +0100
@@ -2876,6 +2876,12 @@ static void Luks2KeyslotParams(void)
 	const char *mk_hex2 = "bb21158c733229347bd4e681891e213d94c685be6a5b84818afe7a78a6de7a1e";
 	size_t key_size_ret, key_size = strlen(mk_hex) / 2, keyslot_key_size = 16;
 	uint64_t r_payload_offset;
+	const struct crypt_pbkdf_type fast_pbkdf = {
+		.type = "pbkdf2",
+		.hash = "sha256",
+		.iterations = 1000,
+		.flags = CRYPT_PBKDF_NO_BENCHMARK
+	};
 
 	crypt_decode_key(key, mk_hex, key_size);
 	crypt_decode_key(key2, mk_hex2, key_size);
@@ -2889,7 +2895,7 @@ static void Luks2KeyslotParams(void)
 	EQ_(key_size, 2 * keyslot_key_size);
 	/* test crypt_keyslot_add_by_key */
 	OK_(crypt_init(&cd, DMDIR L_DEVICE_OK));
-	crypt_set_iteration_time(cd, 1);
+	OK_(crypt_set_pbkdf_type(cd, &fast_pbkdf));
 	OK_(crypt_format(cd, CRYPT_LUKS2, cipher, cipher_mode, NULL, key, key_size, NULL));
 	NULL_(crypt_keyslot_get_encryption(cd, 0, &key_size_ret));
 	OK_(strcmp(crypt_keyslot_get_encryption(cd, CRYPT_ANY_SLOT, &key_size_ret), cipher_spec));
@@ -2948,7 +2954,7 @@ static void Luks2KeyslotParams(void)
 	OK_(strcmp(crypt_keyslot_get_encryption(cd, 7, &key_size_ret), cipher_keyslot));
 	EQ_(key_size_ret, keyslot_key_size);
 
-	crypt_set_iteration_time(cd, 1);
+	OK_(crypt_set_pbkdf_type(cd, &fast_pbkdf));
 	EQ_(8, crypt_keyslot_change_by_passphrase(cd, 1, 8, PASSPHRASE1, strlen(PASSPHRASE1), PASSPHRASE, strlen(PASSPHRASE)));
 	OK_(strcmp(crypt_keyslot_get_encryption(cd, 8, &key_size_ret), cipher_spec));
 	EQ_(key_size_ret, key_size);
@@ -2977,7 +2983,7 @@ static void Luks2KeyslotParams(void)
 
 	/* LUKS1 compatible calls */
 	OK_(crypt_init(&cd, DMDIR L_DEVICE_OK));
-	crypt_set_iteration_time(cd, 1);
+	OK_(crypt_set_pbkdf_type(cd, &fast_pbkdf));
 	OK_(crypt_format(cd, CRYPT_LUKS1, cipher, cipher_mode, NULL, key, key_size, NULL));
 	NULL_(crypt_keyslot_get_encryption(cd, 0, &key_size_ret));
 	OK_(strcmp(crypt_keyslot_get_encryption(cd, CRYPT_ANY_SLOT, &key_size_ret), cipher_spec));
@@ -2987,6 +2993,18 @@ static void Luks2KeyslotParams(void)
 	EQ_(key_size_ret, key_size);
 	CRYPT_FREE(cd);
 
+	/* LUKS2 cipher null checks */
+	OK_(crypt_init(&cd, DMDIR L_DEVICE_OK));
+	OK_(crypt_set_pbkdf_type(cd, &fast_pbkdf));
+	OK_(crypt_format(cd, CRYPT_LUKS2, "cipher_null", "ecb", NULL, key, key_size, NULL));
+	FAIL_(crypt_keyslot_set_encryption(cd, "null", 32), "cipher null is not allowed");
+	FAIL_(crypt_keyslot_set_encryption(cd, "cipher_null", 32), "cipher null is not allowed");
+	FAIL_(crypt_keyslot_set_encryption(cd, "cipher_null-ecb", 32), "cipher null is not allowed");
+	EQ_(0, crypt_keyslot_add_by_volume_key(cd, 0, key, key_size, PASSPHRASE, strlen(PASSPHRASE)));
+	NOTNULL_(crypt_keyslot_get_encryption(cd, 0, &key_size_ret));
+	NULL_(strstr(crypt_keyslot_get_encryption(cd, 0, &key_size_ret), "null"));
+	CRYPT_FREE(cd);
+
 	_cleanup_dmdevices();
 	_remove_keyfiles();
 }
diff -rupN cryptsetup-2.3.3.orig/tests/luks2-reencryption-test cryptsetup-2.3.3/tests/luks2-reencryption-test
--- cryptsetup-2.3.3.orig/tests/luks2-reencryption-test	2021-02-17 19:48:46.493519309 +0100
+++ cryptsetup-2.3.3/tests/luks2-reencryption-test	2021-02-17 19:50:13.397427467 +0100
@@ -1365,6 +1365,33 @@ echo $PWD1 | $CRYPTSETUP luksKillSlot $D
 echo -e "$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD2" | $CRYPTSETUP reencrypt $DEV -q 2>/dev/null && fail
 echo $PWD1 | $CRYPTSETUP reencrypt $DEV --resume-only -q 2>/dev/null && fail
 echo -e "$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1\n$PWD1" | $CRYPTSETUP reencrypt $DEV -q  || fail
+ 
+echo "[24] Reencryption with initial cipher_null"
+# aka custom encryption
+prepare dev_size_mb=32
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -s 128 -c cipher_null-ecb --offset 8192 $FAST_PBKDF_ARGON $DEV || fail
+wipe $PWD1
+check_hash $PWD1 $HASH1
+echo $PWD1 | $CRYPTSETUP reencrypt $DEV -c aes-xts-plain64 -q $FAST_PBKDF_ARGON || fail
+check_hash $PWD1 $HASH1
+
+# online
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -s 128 -c cipher_null-ecb --offset 8192 $FAST_PBKDF_ARGON $DEV || fail
+wipe $PWD1
+echo $PWD1 | $CRYPTSETUP open $DEV $DEV_NAME
+echo $PWD1 | $CRYPTSETUP reencrypt $DEV -c aes-xts-plain64 -q $FAST_PBKDF_ARGON || fail
+check_hash_dev /dev/mapper/$DEV_NAME $HASH1
+$CRYPTSETUP status $DEV_NAME | grep -q "key location: keyring" || fail
+$CRYPTSETUP close $DEV_NAME
+
+# simulate LUKS2 device with cipher_null in both keyslot and segment (it can be created only by up conversion from LUKS1)
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks1 -s 128 -c cipher_null-ecb --offset 8192 $FAST_PBKDF2 $DEV || fail
+$CRYPTSETUP convert -q --type luks2 $DEV || fail
+wipe $PWD1
+echo $PWD1 | $CRYPTSETUP reencrypt $DEV -c aes-xts-plain64 -q $FAST_PBKDF_ARGON || fail
+check_hash $PWD1 $HASH1
+# both keyslot and segment cipher must not be null
+$CRYPTSETUP luksDump $DEV | grep -q "cipher_null" && fail
 
 remove_mapping
 exit 0
diff -rupN cryptsetup-2.3.3.orig/lib/utils_crypt.c cryptsetup-2.3.3/lib/utils_crypt.c
--- cryptsetup-2.3.3.orig/lib/utils_crypt.c	2021-02-17 17:48:06.535007396 +0100
+++ cryptsetup-2.3.3/lib/utils_crypt.c	2021-02-17 17:49:07.552948180 +0100
@@ -174,3 +174,10 @@ ssize_t crypt_hex_to_bytes(const char *h
 	*result = bytes;
 	return i;
 }
+
+bool crypt_is_cipher_null(const char *cipher_spec)
+{
+	if (!cipher_spec)
+		return false;
+	return (strstr(cipher_spec, "cipher_null") || !strcmp(cipher_spec, "null"));
+}
diff -rupN cryptsetup-2.3.3.orig/lib/utils_crypt.h cryptsetup-2.3.3/lib/utils_crypt.h
--- cryptsetup-2.3.3.orig/lib/utils_crypt.h	2021-02-17 17:48:06.535007396 +0100
+++ cryptsetup-2.3.3/lib/utils_crypt.h	2021-02-17 17:49:07.552948180 +0100
@@ -23,6 +23,7 @@
 #ifndef _UTILS_CRYPT_H
 #define _UTILS_CRYPT_H
 
+#include <stdbool.h>
 #include <unistd.h>
 
 #define MAX_CIPHER_LEN		32
@@ -38,4 +39,6 @@ int crypt_parse_pbkdf(const char *s, con
 
 ssize_t crypt_hex_to_bytes(const char *hex, char **result, int safe_alloc);
 
+bool crypt_is_cipher_null(const char *cipher_spec);
+
 #endif /* _UTILS_CRYPT_H */
diff -rupN cryptsetup-2.3.3.orig/src/cryptsetup.c cryptsetup-2.3.3/src/cryptsetup.c
--- cryptsetup-2.3.3.orig/src/cryptsetup.c	2021-02-17 17:48:06.538007393 +0100
+++ cryptsetup-2.3.3/src/cryptsetup.c	2021-02-17 17:52:54.174722763 +0100
@@ -1281,7 +1281,7 @@ static int _luksFormat(struct crypt_devi
 	}
 
 	/* Never call pwquality if using null cipher */
-	if (tools_is_cipher_null(cipher))
+	if (crypt_is_cipher_null(cipher))
 		opt_force_password = 1;
 
 	if ((r = crypt_init(&cd, header_device))) {
@@ -1679,7 +1679,7 @@ static int luksAddUnboundKey(void)
 		goto out;
 
 	/* Never call pwquality if using null cipher */
-	if (tools_is_cipher_null(crypt_get_cipher(cd)))
+	if (crypt_is_cipher_null(crypt_get_cipher(cd)))
 		opt_force_password = 1;
 
 	keysize = opt_key_size / 8;
@@ -1746,7 +1746,7 @@ static int action_luksAddKey(void)
 		goto out;
 
 	/* Never call pwquality if using null cipher */
-	if (tools_is_cipher_null(crypt_get_cipher(cd)))
+	if (crypt_is_cipher_null(crypt_get_cipher(cd)))
 		opt_force_password = 1;
 
 	keysize = crypt_get_volume_key_size(cd);
@@ -1849,7 +1849,7 @@ static int action_luksChangeKey(void)
 		goto out;
 
 	/* Never call pwquality if using null cipher */
-	if (tools_is_cipher_null(crypt_get_cipher(cd)))
+	if (crypt_is_cipher_null(crypt_get_cipher(cd)))
 		opt_force_password = 1;
 
 	r = set_pbkdf_params(cd, crypt_get_type(cd));
diff -rupN cryptsetup-2.3.3.orig/src/cryptsetup.h cryptsetup-2.3.3/src/cryptsetup.h
--- cryptsetup-2.3.3.orig/src/cryptsetup.h	2021-02-17 17:48:06.538007393 +0100
+++ cryptsetup-2.3.3/src/cryptsetup.h	2021-02-17 17:54:15.556641129 +0100
@@ -97,7 +97,6 @@ int tools_get_key(const char *prompt,
 void tools_passphrase_msg(int r);
 int tools_is_stdin(const char *key_file);
 int tools_string_to_size(struct crypt_device *cd, const char *s, uint64_t *size);
-int tools_is_cipher_null(const char *cipher);
 
 void tools_clear_line(void);
 
diff -rupN cryptsetup-2.3.3.orig/src/utils_tools.c cryptsetup-2.3.3/src/utils_tools.c
--- cryptsetup-2.3.3.orig/src/utils_tools.c	2021-02-17 17:48:06.538007393 +0100
+++ cryptsetup-2.3.3/src/utils_tools.c	2021-02-17 17:49:07.572948160 +0100
@@ -596,14 +596,6 @@ out:
 	return r;
 }
 
-int tools_is_cipher_null(const char *cipher)
-{
-	if (!cipher)
-		return 0;
-
-	return !strcmp(cipher, "cipher_null") ? 1 : 0;
-}
-
 /*
  * Keyfile - is standard input treated as a binary file (no EOL handling).
  */
From 03cc8a9ce4c1e04283eb0e0da658aa4509e74949 Mon Sep 17 00:00:00 2001
From: Ondrej Kozina <okozina@redhat.com>
Date: Wed, 10 Feb 2021 17:50:49 +0100
Subject: [PATCH 3/9] Fix broken detection of null cipher in LUKS2.

This bug enabled to create LUKS2 keyslots encrypted by
cipher_null when explicitely requested by user. LUKS2
was never meant to allow keyslot encryption with
cipher_null. cipher_null is meant for debug purposes
only as a segment cipher.
---
 lib/luks2/luks2_keyslot.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/luks2/luks2_keyslot.c b/lib/luks2/luks2_keyslot.c
index ed51e24..414189c 100644
--- a/lib/luks2/luks2_keyslot.c
+++ b/lib/luks2/luks2_keyslot.c
@@ -155,7 +155,7 @@ int LUKS2_keyslot_cipher_incompatible(struct crypt_device *cd, const char *ciphe
 {
 	char cipher[MAX_CIPHER_LEN], cipher_mode[MAX_CIPHER_LEN];
 
-	if (!cipher_spec || !strcmp(cipher_spec, "null") || !strcmp(cipher_spec, "cipher_null"))
+	if (!cipher_spec || crypt_is_cipher_null(cipher_spec))
 		return 1;
 
 	if (crypt_parse_name_and_mode(cipher_spec, cipher, NULL, cipher_mode) < 0)
-- 
1.8.3.1

diff -rupN cryptsetup-2.3.3.orig/lib/luks2/luks2_token.c cryptsetup-2.3.3/lib/luks2/luks2_token.c
--- cryptsetup-2.3.3.orig/lib/luks2/luks2_token.c	2021-02-17 17:59:35.532320163 +0100
+++ cryptsetup-2.3.3/lib/luks2/luks2_token.c	2021-02-17 18:01:49.925185354 +0100
@@ -383,6 +383,7 @@ int LUKS2_token_open_and_activate(struct
 		uint32_t flags,
 		void *usrptr)
 {
+	bool use_keyring;
 	int keyslot, r;
 	char *buffer;
 	size_t buffer_len;
@@ -404,7 +405,13 @@ int LUKS2_token_open_and_activate(struct
 
 	keyslot = r;
 
-	if ((name || (flags & CRYPT_ACTIVATE_KEYRING_KEY)) && crypt_use_keyring_for_vk(cd)) {
+	if (!crypt_use_keyring_for_vk(cd))
+		use_keyring = false;
+	else
+		use_keyring = ((name && !crypt_is_cipher_null(crypt_get_cipher(cd))) ||
+			       (flags & CRYPT_ACTIVATE_KEYRING_KEY));
+
+	if (use_keyring) {
 		if (!(r = LUKS2_volume_key_load_in_keyring_by_keyslot(cd, hdr, vk, keyslot)))
 			flags |= CRYPT_ACTIVATE_KEYRING_KEY;
 	}
diff -rupN cryptsetup-2.3.3.orig/lib/setup.c cryptsetup-2.3.3/lib/setup.c
--- cryptsetup-2.3.3.orig/lib/setup.c	2021-02-17 17:59:35.529320166 +0100
+++ cryptsetup-2.3.3/lib/setup.c	2021-02-17 18:00:03.676291932 +0100
@@ -3879,6 +3879,7 @@ static int _open_and_activate(struct cry
 	size_t passphrase_size,
 	uint32_t flags)
 {
+	bool use_keyring;
 	int r;
 	struct volume_key *vk = NULL;
 
@@ -3890,8 +3891,13 @@ static int _open_and_activate(struct cry
 		return r;
 	keyslot = r;
 
-	if ((name || (flags & CRYPT_ACTIVATE_KEYRING_KEY)) &&
-	    crypt_use_keyring_for_vk(cd)) {
+	if (!crypt_use_keyring_for_vk(cd))
+		use_keyring = false;
+	else
+		use_keyring = ((name && !crypt_is_cipher_null(crypt_get_cipher(cd))) ||
+			       (flags & CRYPT_ACTIVATE_KEYRING_KEY));
+
+	if (use_keyring) {
 		r = LUKS2_volume_key_load_in_keyring_by_keyslot(cd,
 				&cd->u.luks2.hdr, vk, keyslot);
 		if (r < 0)
@@ -4269,6 +4275,7 @@ int crypt_activate_by_volume_key(struct
 	size_t volume_key_size,
 	uint32_t flags)
 {
+	bool use_keyring;
 	struct volume_key *vk = NULL;
 	int r;
 
@@ -4344,8 +4351,12 @@ int crypt_activate_by_volume_key(struct
 		if (r > 0)
 			r = 0;
 
-		if (!r && (name || (flags & CRYPT_ACTIVATE_KEYRING_KEY)) &&
-		    crypt_use_keyring_for_vk(cd)) {
+		if (!crypt_use_keyring_for_vk(cd))
+			use_keyring = false;
+		else
+			use_keyring = (name && !crypt_is_cipher_null(crypt_get_cipher(cd))) || (flags & CRYPT_ACTIVATE_KEYRING_KEY);
+
+		if (!r && use_keyring) {
 			r = LUKS2_key_description_by_segment(cd,
 				&cd->u.luks2.hdr, vk, CRYPT_DEFAULT_SEGMENT);
 			if (!r)
From ed2117c72417d85c7b2f20d5859ca558eaf61c62 Mon Sep 17 00:00:00 2001
From: Ondrej Kozina <okozina@redhat.com>
Date: Thu, 11 Feb 2021 11:43:10 +0100
Subject: [PATCH 5/9] Fix device comparison for dm-crypt with cipher_null.

Do not compare volume keys if segment uses cipher_null.
The key is ignored by lower layer (internal libdevmapper)
anyway.
---
 lib/setup.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/lib/setup.c b/lib/setup.c
index ffd9b7b..7286e10 100644
--- a/lib/setup.c
+++ b/lib/setup.c
@@ -2380,11 +2380,6 @@ static int _compare_crypt_devices(struct crypt_device *cd,
 	if (!src->u.crypt.vk || !tgt->u.crypt.vk)
 		return -EINVAL;
 
-	if (_compare_volume_keys(src->u.crypt.vk, 0, tgt->u.crypt.vk, tgt->u.crypt.vk->key_description != NULL)) {
-		log_dbg(cd, "Keys in context and target device do not match.");
-		return -EINVAL;
-	}
-
 	/* CIPHER checks */
 	if (!src->u.crypt.cipher || !tgt->u.crypt.cipher)
 		return -EINVAL;
@@ -2392,6 +2387,14 @@ static int _compare_crypt_devices(struct crypt_device *cd,
 		log_dbg(cd, "Cipher specs do not match.");
 		return -EINVAL;
 	}
+
+	if (tgt->u.crypt.vk->keylength == 0 && crypt_is_cipher_null(tgt->u.crypt.cipher))
+		log_dbg(cd, "Existing device uses cipher null. Skipping key comparison.");
+	else if (_compare_volume_keys(src->u.crypt.vk, 0, tgt->u.crypt.vk, tgt->u.crypt.vk->key_description != NULL)) {
+		log_dbg(cd, "Keys in context and target device do not match.");
+		return -EINVAL;
+	}
+
 	if (crypt_strcmp(src->u.crypt.integrity, tgt->u.crypt.integrity)) {
 		log_dbg(cd, "Integrity parameters do not match.");
 		return -EINVAL;
-- 
1.8.3.1

From 01f896711ed54bff7c1ccf944d2295929af7c75c Mon Sep 17 00:00:00 2001
From: Ondrej Kozina <okozina@redhat.com>
Date: Thu, 11 Feb 2021 12:17:02 +0100
Subject: [PATCH 6/9] Replace bogus cipher_null keyslots before reencryption.

By mistake LUKS2 allowed keyslots 'not-so-encrypted' by
cipher_null (only explicitly requested by --cipher or
--keyslot-cipher parameters). If we encounter
such old key during reencryption let's replace the cipher
for new keyslot with default LUKS2 keyslot cipher.
---
 src/cryptsetup.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/cryptsetup.c b/src/cryptsetup.c
index 957c24e..5e22286 100644
--- a/src/cryptsetup.c
+++ b/src/cryptsetup.c
@@ -1091,6 +1091,12 @@ static int set_keyslot_params(struct crypt_device *cd, int keyslot)
 	if (!cipher)
 		return -EINVAL;
 
+	if (crypt_is_cipher_null(cipher)) {
+		log_dbg("Keyslot %d uses cipher_null. Replacing with default encryption in new keyslot.", keyslot);
+		cipher = DEFAULT_LUKS2_KEYSLOT_CIPHER;
+		key_size = DEFAULT_LUKS2_KEYSLOT_KEYBITS / 8;
+	}
+
 	if (crypt_keyslot_set_encryption(cd, cipher, key_size))
 		return -EINVAL;
 
-- 
1.8.3.1

diff -rupN cryptsetup-2.3.3.orig/lib/luks2/luks2_reencrypt.c cryptsetup-2.3.3/lib/luks2/luks2_reencrypt.c
--- cryptsetup-2.3.3.orig/lib/luks2/luks2_reencrypt.c	2021-02-17 18:03:49.547065362 +0100
+++ cryptsetup-2.3.3/lib/luks2/luks2_reencrypt.c	2021-02-17 18:09:43.610710202 +0100
@@ -2238,7 +2238,7 @@ static int reencrypt_verify_and_upload_k
 			if (LUKS2_digest_verify_by_digest(cd, hdr, digest_new, vk) != digest_new)
 				return -EINVAL;
 
-			if (crypt_use_keyring_for_vk(cd) &&
+			if (crypt_use_keyring_for_vk(cd) && !crypt_is_cipher_null(reencrypt_segment_cipher_new(hdr)) &&
 			    (r = LUKS2_volume_key_load_in_keyring_by_digest(cd, hdr, vk, crypt_volume_key_get_id(vk))))
 				return r;
 		}
@@ -2254,7 +2254,7 @@ static int reencrypt_verify_and_upload_k
 				r = -EINVAL;
 				goto err;
 			}
-			if (crypt_use_keyring_for_vk(cd) &&
+			if (crypt_use_keyring_for_vk(cd) && !crypt_is_cipher_null(reencrypt_segment_cipher_old(hdr)) &&
 			    (r = LUKS2_volume_key_load_in_keyring_by_digest(cd, hdr, vk, crypt_volume_key_get_id(vk))))
 				goto err;
 		}
@@ -2664,6 +2664,7 @@ static int reencrypt_load_by_passphrase(
 	struct luks2_hdr *hdr;
 	struct crypt_lock_handle *reencrypt_lock;
 	struct luks2_reenc_context *rh;
+	const struct volume_key *vk;
 	struct crypt_dm_active_device dmd_target, dmd_source = {
 		.uuid = crypt_get_uuid(cd),
 		.flags = CRYPT_ACTIVATE_SHARED /* turn off exclusive open checks */
@@ -2730,6 +2731,19 @@ static int reencrypt_load_by_passphrase(
 			goto err;
 		flags = dmd_target.flags;
 
+		/*
+		 * By default reencryption code aims to retain flags from existing dm device.
+		 * The keyring activation flag can not be inherited if original cipher is null.
+		 *
+		 * In this case override the flag based on decision made in reencrypt_verify_and_upload_keys
+		 * above. The code checks if new VK is eligible for keyring.
+		 */
+		vk = crypt_volume_key_by_id(*vks, LUKS2_reencrypt_digest_new(hdr));
+		if (vk && vk->key_description && crypt_is_cipher_null(reencrypt_segment_cipher_old(hdr))) {
+			flags |= CRYPT_ACTIVATE_KEYRING_KEY;
+			dmd_source.flags |= CRYPT_ACTIVATE_KEYRING_KEY;
+		}
+
 		r = LUKS2_assembly_multisegment_dmd(cd, hdr, *vks, LUKS2_get_segments_jobj(hdr), &dmd_source);
 		if (!r) {
 			r = crypt_compare_dm_devices(cd, &dmd_source, &dmd_target);
diff -rupN cryptsetup-2.3.3.orig/src/cryptsetup.c cryptsetup-2.3.3/src/cryptsetup.c
--- cryptsetup-2.3.3.orig/src/cryptsetup.c	2021-02-17 18:12:12.162561190 +0100
+++ cryptsetup-2.3.3/src/cryptsetup.c	2021-02-17 18:19:04.842147234 +0100
@@ -3142,6 +3142,11 @@ static int action_reencrypt_luks2(struct
 
 	_set_reencryption_flags(&params.flags);
 
+	if (!opt_cipher && crypt_is_cipher_null(crypt_get_cipher(cd))) {
+		log_std(_("Switching data encryption cipher to %s.\n"), DEFAULT_CIPHER(LUKS1));
+		opt_cipher = DEFAULT_CIPHER(LUKS1);
+	}
+
 	if (!opt_cipher) {
 		strncpy(cipher, crypt_get_cipher(cd), MAX_CIPHER_LEN - 1);
 		strncpy(mode, crypt_get_cipher_mode(cd), MAX_CIPHER_LEN - 1);
diff -rupN cryptsetup-2.3.3.orig/tests/luks2-reencryption-test cryptsetup-2.3.3/tests/luks2-reencryption-test
--- cryptsetup-2.3.3.orig/tests/luks2-reencryption-test	2021-02-17 18:25:01.393788684 +0100
+++ cryptsetup-2.3.3/tests/luks2-reencryption-test	2021-02-17 18:26:00.864726663 +0100
@@ -1388,9 +1388,9 @@ $CRYPTSETUP close $DEV_NAME
 echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks1 -s 128 -c cipher_null-ecb --offset 8192 $FAST_PBKDF2 $DEV || fail
 $CRYPTSETUP convert -q --type luks2 $DEV || fail
 wipe $PWD1
-echo $PWD1 | $CRYPTSETUP reencrypt $DEV -c aes-xts-plain64 -q $FAST_PBKDF_ARGON || fail
+echo $PWD1 | $CRYPTSETUP reencrypt $DEV -q $FAST_PBKDF_ARGON >/dev/null || fail
 check_hash $PWD1 $HASH1
-# both keyslot and segment cipher must not be null
+# both keyslot and segment cipher must not be null after reencryption with default params
 $CRYPTSETUP luksDump $DEV | grep -q "cipher_null" && fail
 
 remove_mapping
From 030d50f6baff62466c611c868d860c6c3a3efef9 Mon Sep 17 00:00:00 2001
From: Ondrej Kozina <okozina@redhat.com>
Date: Wed, 17 Feb 2021 15:00:19 +0100
Subject: [PATCH] Fix reencryption test on systems w/o keyring.

---
 tests/luks2-reencryption-test | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/tests/luks2-reencryption-test b/tests/luks2-reencryption-test
index 51b5473..6e6b381 100755
--- a/tests/luks2-reencryption-test
+++ b/tests/luks2-reencryption-test
@@ -654,6 +654,18 @@ function reencrypt_online_fixed_size() {
 	fi
 }
 
+function setup_luks2_env() {
+	echo $PWD1 | $CRYPTSETUP luksFormat --type luks2 $FAST_PBKDF_ARGON $DEV || fail
+	echo $PWD1 | $CRYPTSETUP open $DEV $DEV_NAME || fail
+	HAVE_KEYRING=$($CRYPTSETUP status $DEV_NAME | grep "key location: keyring")
+	if [ -n "$HAVE_KEYRING" ]; then
+		HAVE_KEYRING=1
+	else
+		HAVE_KEYRING=0
+	fi
+	$CRYPTSETUP close $DEV_NAME || fail
+}
+
 function valgrind_setup()
 {
 	which valgrind >/dev/null 2>&1 || fail "Cannot find valgrind."
@@ -705,9 +717,11 @@ HASH7=18a393d1a505e22ccf3e29effe3005ea8627e4c36b7cca0e53f58121f49b67e1
 # 60 MiBs of zeroes
 HASH8=cf5ac69ca412f9b3b1a8b8de27d368c5c05ed4b1b6aa40e6c38d9cbf23711342
 
+prepare dev_size_mb=32
+setup_luks2_env
+
 echo "[1] Reencryption"
 echo -n "[512 sector]"
-prepare dev_size_mb=32
 echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -s 128 -c aes-cbc-essiv:sha256 --offset 8192 $FAST_PBKDF_ARGON $DEV || fail
 wipe $PWD1
 check_hash $PWD1 $HASH1
@@ -1412,7 +1426,9 @@ wipe $PWD1
 echo $PWD1 | $CRYPTSETUP open $DEV $DEV_NAME
 echo $PWD1 | $CRYPTSETUP reencrypt $DEV -c aes-xts-plain64 -q $FAST_PBKDF_ARGON || fail
 check_hash_dev /dev/mapper/$DEV_NAME $HASH1
-$CRYPTSETUP status $DEV_NAME | grep -q "key location: keyring" || fail
+if [ $HAVE_KEYRING -gt 0 ]; then
+	$CRYPTSETUP status $DEV_NAME | grep -q "key location: keyring" || fail
+fi
 $CRYPTSETUP close $DEV_NAME
 
 # simulate LUKS2 device with cipher_null in both keyslot and segment (it can be created only by up conversion from LUKS1)
-- 
1.8.3.1

diff -rupN cryptsetup-2.3.3.orig/src/cryptsetup.c cryptsetup-2.3.3/src/cryptsetup.c
--- cryptsetup-2.3.3.orig/src/cryptsetup.c	2021-02-18 12:37:44.903909498 +0100
+++ cryptsetup-2.3.3/src/cryptsetup.c	2021-02-18 12:45:49.208492236 +0100
@@ -1196,6 +1196,21 @@ static int strcmp_or_null(const char *st
 	return !str ? 0 : strcmp(str, expected);
 }
 
+static int get_adjusted_key_size(const char *cipher_mode, uint32_t default_size_bits, int integrity_keysize)
+{
+	int keysize_bits = opt_key_size;
+
+#ifdef ENABLE_LUKS_ADJUST_XTS_KEYSIZE
+	if (!opt_key_size && !strncmp(cipher_mode, "xts-", 4)) {
+		if (default_size_bits == 128)
+			keysize_bits = 256;
+		else if (default_size_bits == 256)
+			keysize_bits = 512;
+	}
+#endif
+	return (keysize_bits ?: default_size_bits) / 8 + integrity_keysize;
+}
+
 static int _luksFormat(struct crypt_device **r_cd, char **r_password, size_t *r_passwordLen)
 {
 	int r = -EINVAL, keysize, integrity_keysize = 0, fd, created = 0;
@@ -1328,15 +1343,7 @@ static int _luksFormat(struct crypt_devi
 			goto out;
 	}
 
-#ifdef ENABLE_LUKS_ADJUST_XTS_KEYSIZE
-	if (!opt_key_size && !strncmp(cipher_mode, "xts-", 4)) {
-		if (DEFAULT_LUKS1_KEYBITS == 128)
-			opt_key_size = 256;
-		else if (DEFAULT_LUKS1_KEYBITS == 256)
-			opt_key_size = 512;
-	}
-#endif
-	keysize = (opt_key_size ?: DEFAULT_LUKS1_KEYBITS) / 8 + integrity_keysize;
+	keysize = get_adjusted_key_size(cipher_mode, DEFAULT_LUKS1_KEYBITS, integrity_keysize);
 
 	if (opt_random)
 		crypt_set_rng_type(cd, CRYPT_RNG_RANDOM);
@@ -3163,10 +3170,8 @@ static int action_reencrypt_luks2(struct
 	if (r)
 		return r;
 
-	if (opt_key_size)
-		key_size = opt_key_size / 8;
-	else if (opt_cipher)
-		key_size = DEFAULT_LUKS1_KEYBITS / 8;
+	if (opt_key_size || opt_cipher)
+		key_size = get_adjusted_key_size(mode, DEFAULT_LUKS1_KEYBITS, 0);
 	else
 		key_size = crypt_get_volume_key_size(cd);
 
diff -rupN cryptsetup-2.3.3.orig/tests/luks2-reencryption-test cryptsetup-2.3.3/tests/luks2-reencryption-test
--- cryptsetup-2.3.3.orig/tests/luks2-reencryption-test	2021-02-18 12:37:44.916909486 +0100
+++ cryptsetup-2.3.3/tests/luks2-reencryption-test	2021-02-18 12:39:33.589815857 +0100
@@ -648,7 +648,7 @@ function reencrypt_online_fixed_size() {
 }
 
 function setup_luks2_env() {
-	echo $PWD1 | $CRYPTSETUP luksFormat --type luks2 $FAST_PBKDF_ARGON $DEV || fail
+	echo $PWD1 | $CRYPTSETUP luksFormat --type luks2 -c aes-xts-plain64 $FAST_PBKDF_ARGON $DEV || fail
 	echo $PWD1 | $CRYPTSETUP open $DEV $DEV_NAME || fail
 	HAVE_KEYRING=$($CRYPTSETUP status $DEV_NAME | grep "key location: keyring")
 	if [ -n "$HAVE_KEYRING" ]; then
@@ -656,6 +656,8 @@ function setup_luks2_env() {
 	else
 		HAVE_KEYRING=0
 	fi
+	DEF_XTS_KEY=$($CRYPTSETUP status $DEV_NAME | grep "keysize:" | sed 's/\(  keysize: \)\([0-9]\+\)\(.*\)/\2/')
+	[ -n "$DEF_XTS_KEY" ] || fail "Failed to parse xts mode key size."
 	$CRYPTSETUP close $DEV_NAME || fail
 }
 
@@ -730,6 +732,8 @@ check_hash $PWD1 $HASH1
 echo $PWD1 | $CRYPTSETUP reencrypt $DEV -q -c aes-xts-plain64 --init-only $FAST_PBKDF_ARGON || fail
 echo $PWD1 | $CRYPTSETUP open $DEV $DEV_NAME || fail
 echo $PWD1 | $CRYPTSETUP reencrypt --active-name /dev/mapper/$DEV_NAME --resilience none -q || fail
+XTS_KEY=$($CRYPTSETUP status $DEV_NAME | grep "keysize:" | sed 's/\(  keysize: \)\([0-9]\+\)\(.*\)/\2/')
+[ "$XTS_KEY" -eq "$DEF_XTS_KEY" ] || fail "xts mode has wrong key size after reencryption ($XTS_KEY != expected $DEF_XTS_KEY)"
 echo $PWD1 | $CRYPTSETUP close $DEV_NAME || fail
 echo -n "[OK][4096 sector]"
 prepare sector_size=4096 dev_size_mb=32
diff -rupN cryptsetup-2.3.3.orig/lib/libdevmapper.c cryptsetup-2.3.3/lib/libdevmapper.c
--- cryptsetup-2.3.3.orig/lib/libdevmapper.c	2021-02-18 16:21:00.863470374 +0100
+++ cryptsetup-2.3.3/lib/libdevmapper.c	2021-02-18 16:22:36.330393562 +0100
@@ -639,11 +639,13 @@ static char *get_dm_crypt_params(const s
 	if (!strncmp(cipher_dm, "cipher_null-", 12))
 		null_cipher = 1;
 
-	if (flags & CRYPT_ACTIVATE_KEYRING_KEY) {
+	if (null_cipher)
+		hexkey = crypt_safe_alloc(2);
+	else if (flags & CRYPT_ACTIVATE_KEYRING_KEY) {
 		keystr_len = strlen(tgt->u.crypt.vk->key_description) + int_log10(tgt->u.crypt.vk->keylength) + 10;
 		hexkey = crypt_safe_alloc(keystr_len);
 	} else
-		hexkey = crypt_safe_alloc(null_cipher ? 2 : (tgt->u.crypt.vk->keylength * 2 + 1));
+		hexkey = crypt_safe_alloc(tgt->u.crypt.vk->keylength * 2 + 1);
 
 	if (!hexkey)
 		return NULL;
From 284a49443e2a833e33714f9fa0f03b8e0233d68d Mon Sep 17 00:00:00 2001
From: Ondrej Kozina <okozina@redhat.com>
Date: Thu, 18 Feb 2021 15:01:01 +0100
Subject: [PATCH 3/3] Extend LUKS2 reencryption tests w/ cipher_null.

---
 tests/luks2-reencryption-test | 106 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 104 insertions(+), 2 deletions(-)

diff --git a/tests/luks2-reencryption-test b/tests/luks2-reencryption-test
index 9bdf60a..05c2151 100755
--- a/tests/luks2-reencryption-test
+++ b/tests/luks2-reencryption-test
@@ -297,7 +297,7 @@ function reencrypt_recover() { # $1 sector size, $2 resilience, $3 digest, [$4 h
 	test -z "$4" || _hdr="--header $4"
 
 	error_writes $OVRDEV $OLD_DEV $ERROFFSET $ERRLENGTH
-	echo $PWD1 | $CRYPTSETUP reencrypt $DEV $_hdr --hotzone-size 1M --resilience $2 --sector-size $1 -q $FAST_PBKDF_ARGON 2>/dev/null && fail
+	echo $PWD1 | $CRYPTSETUP reencrypt $DEV $_hdr --hotzone-size 1M --resilience $2 --sector-size $1 -q $FAST_PBKDF_ARGON >/dev/null 2>&1 && fail
 	fix_writes $OVRDEV $OLD_DEV
 
 	echo $PWD1 | $CRYPTSETUP -q repair $DEV $_hdr || fail
@@ -318,7 +318,7 @@ function reencrypt_recover_online() { # $1 sector size, $2 resilience, $3 digest
 	echo $PWD1 | $CRYPTSETUP open $DEV $_hdr $DEV_NAME || fail
 
 	error_writes $OVRDEV $OLD_DEV $ERROFFSET $ERRLENGTH
-	echo $PWD1 | $CRYPTSETUP reencrypt --active-name $DEV_NAME $_hdr --hotzone-size 1M --resilience $2 --sector-size $1 -q $FAST_PBKDF_ARGON 2>/dev/null && fail
+	echo $PWD1 | $CRYPTSETUP reencrypt --active-name $DEV_NAME $_hdr --hotzone-size 1M --resilience $2 --sector-size $1 -q $FAST_PBKDF_ARGON >/dev/null 2>&1 && fail
 	$CRYPTSETUP status $DEV_NAME $_hdr | grep -q "reencryption:  in-progress" || fail
 	$CRYPTSETUP close $DEV_NAME || fail
 	fix_writes $OVRDEV $OLD_DEV
@@ -1444,5 +1444,107 @@ check_hash $PWD1 $HASH1
 # both keyslot and segment cipher must not be null after reencryption with default params
 $CRYPTSETUP luksDump $DEV | grep -q "cipher_null" && fail
 
+# multistep reencryption with initial cipher_null
+preparebig 64
+echo $PWD1 | $CRYPTSETUP luksFormat --type luks2 $DEV -c null --offset 16384 -q $FAST_PBKDF_ARGON || fail
+echo $PWD1 | $CRYPTSETUP open $DEV $DEV_NAME
+wipe_dev /dev/mapper/$DEV_NAME
+echo $PWD1 | $CRYPTSETUP reencrypt $DEV --hotzone-size 1M --resilience none -q $FAST_PBKDF_ARGON >/dev/null || fail
+$CRYPTSETUP close $DEV_NAME
+check_hash $PWD1 $HASH5
+
+echo $PWD1 | $CRYPTSETUP luksFormat --type luks2 $DEV -c null --offset 16384 -q $FAST_PBKDF_ARGON || fail
+wipe $PWD1
+echo $PWD1 | $CRYPTSETUP reencrypt $DEV --hotzone-size 1M --resilience none -q $FAST_PBKDF_ARGON >/dev/null || fail
+check_hash $PWD1 $HASH5
+
+echo "[25] Reencryption recovery with cipher_null"
+# (check opt-io size optimization in reencryption code does not affect recovery)
+# device with opt-io size 32k
+prepare_linear_dev 32 opt_blks=64 $OPT_XFERLEN_EXP
+OFFSET=8192
+
+echo "sector size 512->512"
+
+get_error_offsets 32 $OFFSET
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 512 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+wipe $PWD1
+check_hash $PWD1 $HASH1
+
+echo "ERR writes to sectors [$ERROFFSET,$(($ERROFFSET+$ERRLENGTH-1))]"
+reencrypt_recover 512 checksum $HASH1
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 512 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+wipe $PWD1
+reencrypt_recover 512 journal $HASH1
+
+if [ -n "$DM_SECTOR_SIZE" ]; then
+	echo "sector size 512->4096"
+
+	get_error_offsets 32 $OFFSET 4096
+	echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 512 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+	wipe $PWD1
+	check_hash $PWD1 $HASH1
+
+	echo "ERR writes to sectors [$ERROFFSET,$(($ERROFFSET+$ERRLENGTH-1))]"
+	reencrypt_recover 4096 checksum $HASH1
+	echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 512 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+	wipe $PWD1
+	check_hash $PWD1 $HASH1
+	reencrypt_recover 4096 journal $HASH1
+
+	echo "sector size 4096->4096"
+
+	get_error_offsets 32 $OFFSET 4096
+	echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 4096 -c aes-cbc-essiv:sha256 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+	wipe $PWD1
+	check_hash $PWD1 $HASH1
+
+	echo "ERR writes to sectors [$ERROFFSET,$(($ERROFFSET+$ERRLENGTH-1))]"
+	reencrypt_recover 4096 checksum $HASH1
+	reencrypt_recover 4096 journal $HASH1
+fi
+
+echo "[26] Reencryption recovery with cipher_null (online i/o error)"
+
+echo "sector size 512->512"
+
+get_error_offsets 32 $OFFSET
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 --sector-size 512 -c null --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+wipe $PWD1
+check_hash $PWD1 $HASH1
+
+echo "ERR writes to sectors [$ERROFFSET,$(($ERROFFSET+$ERRLENGTH-1))]"
+reencrypt_recover_online 512 checksum $HASH1
+echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 --sector-size 512 -c null --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+wipe $PWD1
+reencrypt_recover_online 512 journal $HASH1
+
+if [ -n "$DM_SECTOR_SIZE" ]; then
+	echo "sector size 512->4096"
+
+	get_error_offsets 32 $OFFSET 4096
+	echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 512 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+	wipe $PWD1
+	check_hash $PWD1 $HASH1
+
+	echo "ERR writes to sectors [$ERROFFSET,$(($ERROFFSET+$ERRLENGTH-1))]"
+	reencrypt_recover_online 4096 checksum $HASH1
+	echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 512 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+	wipe $PWD1
+	check_hash $PWD1 $HASH1
+	reencrypt_recover_online 4096 journal $HASH1
+
+	echo "sector size 4096->4096"
+
+	get_error_offsets 32 $OFFSET 4096
+	echo $PWD1 | $CRYPTSETUP -q luksFormat --type luks2 -c null --sector-size 4096 -c aes-cbc-essiv:sha256 --offset $OFFSET $FAST_PBKDF_ARGON $DEV || fail
+	wipe $PWD1
+	check_hash $PWD1 $HASH1
+
+	echo "ERR writes to sectors [$ERROFFSET,$(($ERROFFSET+$ERRLENGTH-1))]"
+	reencrypt_recover_online 4096 checksum $HASH1
+	reencrypt_recover_online 4096 journal $HASH1
+fi
+
 remove_mapping
 exit 0
-- 
1.8.3.1