Adding upstream version 2:2.3.7.upstream/2%2.3.7upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 968 insertions, 0 deletions

diff --git a/lib/luks2/luks2_keyslot.c b/lib/luks2/luks2_keyslot.c
new file mode 100644
index 0000000..d93f2dd
--- /dev/null
+++ b/lib/luks2/luks2_keyslot.c
@@ -0,0 +1,968 @@
+/*
+ * LUKS - Linux Unified Key Setup v2, keyslot handling
+ *
+ * Copyright (C) 2015-2021 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2015-2021 Milan Broz
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "luks2_internal.h"
+
+/* Internal implementations */
+extern const keyslot_handler luks2_keyslot;
+extern const keyslot_handler reenc_keyslot;
+
+static const keyslot_handler *keyslot_handlers[LUKS2_KEYSLOTS_MAX] = {
+	&luks2_keyslot,
+#if USE_LUKS2_REENCRYPTION
+	&reenc_keyslot,
+#endif
+	NULL
+};
+
+static const keyslot_handler
+*LUKS2_keyslot_handler_type(struct crypt_device *cd, const char *type)
+{
+	int i;
+
+	for (i = 0; i < LUKS2_KEYSLOTS_MAX && keyslot_handlers[i]; i++) {
+		if (!strcmp(keyslot_handlers[i]->name, type))
+			return keyslot_handlers[i];
+	}
+
+	return NULL;
+}
+
+static const keyslot_handler
+*LUKS2_keyslot_handler(struct crypt_device *cd, int keyslot)
+{
+	struct luks2_hdr *hdr;
+	json_object *jobj1, *jobj2;
+
+	if (keyslot < 0)
+		return NULL;
+
+	if (!(hdr = crypt_get_hdr(cd, CRYPT_LUKS2)))
+		return NULL;
+
+	if (!(jobj1 = LUKS2_get_keyslot_jobj(hdr, keyslot)))
+		return NULL;
+
+	if (!json_object_object_get_ex(jobj1, "type", &jobj2))
+		return NULL;
+
+	return LUKS2_keyslot_handler_type(cd, json_object_get_string(jobj2));
+}
+
+int LUKS2_keyslot_find_empty(struct luks2_hdr *hdr)
+{
+	int i;
+
+	for (i = 0; i < LUKS2_KEYSLOTS_MAX; i++)
+		if (!LUKS2_get_keyslot_jobj(hdr, i))
+			return i;
+
+	return -EINVAL;
+}
+
+/* Check if a keyslot is assigned to specific segment */
+static int _keyslot_for_segment(struct luks2_hdr *hdr, int keyslot, int segment)
+{
+	int keyslot_digest, count = 0;
+	unsigned s;
+
+	keyslot_digest = LUKS2_digest_by_keyslot(hdr, keyslot);
+	if (keyslot_digest < 0)
+		return keyslot_digest;
+
+	if (segment >= 0)
+		return keyslot_digest == LUKS2_digest_by_segment(hdr, segment);
+
+	for (s = 0; s < json_segments_count(LUKS2_get_segments_jobj(hdr)); s++) {
+		if (keyslot_digest == LUKS2_digest_by_segment(hdr, s))
+			count++;
+	}
+
+	return count;
+}
+
+static int _keyslot_for_digest(struct luks2_hdr *hdr, int keyslot, int digest)
+{
+	int r = -EINVAL;
+
+	r = LUKS2_digest_by_keyslot(hdr, keyslot);
+	if (r < 0)
+		return r;
+	return r == digest ? 0 : -ENOENT;
+}
+
+int LUKS2_keyslot_for_segment(struct luks2_hdr *hdr, int keyslot, int segment)
+{
+	int r = -EINVAL;
+
+	/* no need to check anything */
+	if (segment == CRYPT_ANY_SEGMENT)
+		return 0; /* ok */
+	if (segment == CRYPT_DEFAULT_SEGMENT) {
+		segment = LUKS2_get_default_segment(hdr);
+		if (segment < 0)
+			return segment;
+	}
+
+	r = _keyslot_for_segment(hdr, keyslot, segment);
+	if (r < 0)
+		return r;
+
+	return r >= 1 ? 0 : -ENOENT;
+}
+
+/* Number of keyslots assigned to a segment or all keyslots for CRYPT_ANY_SEGMENT */
+int LUKS2_keyslot_active_count(struct luks2_hdr *hdr, int segment)
+{
+	int num = 0;
+	json_object *jobj_keyslots;
+
+	json_object_object_get_ex(hdr->jobj, "keyslots", &jobj_keyslots);
+
+	json_object_object_foreach(jobj_keyslots, slot, val) {
+		UNUSED(val);
+		if (!LUKS2_keyslot_for_segment(hdr, atoi(slot), segment))
+			num++;
+	}
+
+	return num;
+}
+
+int LUKS2_keyslot_cipher_incompatible(struct crypt_device *cd, const char *cipher_spec)
+{
+	char cipher[MAX_CIPHER_LEN], cipher_mode[MAX_CIPHER_LEN];
+
+	if (!cipher_spec || crypt_is_cipher_null(cipher_spec))
+		return 1;
+
+	if (crypt_parse_name_and_mode(cipher_spec, cipher, NULL, cipher_mode) < 0)
+		return 1;
+
+	/* Keyslot is already authenticated; we cannot use integrity tags here */
+	if (crypt_get_integrity_tag_size(cd))
+		return 1;
+
+	/* Wrapped key schemes cannot be used for keyslot encryption */
+	if (crypt_cipher_wrapped_key(cipher, cipher_mode))
+		return 1;
+
+	/* Check if crypto backend can use the cipher */
+	if (crypt_cipher_ivsize(cipher, cipher_mode) < 0)
+		return 1;
+
+	return 0;
+}
+
+int LUKS2_keyslot_params_default(struct crypt_device *cd, struct luks2_hdr *hdr,
+				 struct luks2_keyslot_params *params)
+{
+	const struct crypt_pbkdf_type *pbkdf = crypt_get_pbkdf_type(cd);
+	const char *cipher_spec;
+	size_t key_size;
+	int r;
+
+	if (!hdr || !pbkdf || !params)
+		return -EINVAL;
+
+	/*
+	 * set keyslot area encryption parameters
+	 */
+	params->area_type = LUKS2_KEYSLOT_AREA_RAW;
+	cipher_spec = crypt_keyslot_get_encryption(cd, CRYPT_ANY_SLOT, &key_size);
+	if (!cipher_spec || !key_size)
+		return -EINVAL;
+
+	params->area.raw.key_size = key_size;
+	r = snprintf(params->area.raw.encryption, sizeof(params->area.raw.encryption), "%s", cipher_spec);
+	if (r < 0 || (size_t)r >= sizeof(params->area.raw.encryption))
+		return -EINVAL;
+
+	/*
+	 * set keyslot AF parameters
+	 */
+	params->af_type = LUKS2_KEYSLOT_AF_LUKS1;
+	/* currently we use hash for AF from pbkdf settings */
+	r = snprintf(params->af.luks1.hash, sizeof(params->af.luks1.hash), "%s", pbkdf->hash ?: DEFAULT_LUKS1_HASH);
+	if (r < 0 || (size_t)r >= sizeof(params->af.luks1.hash))
+		return -EINVAL;
+	params->af.luks1.stripes = 4000;
+
+	return 0;
+}
+
+int LUKS2_keyslot_pbkdf(struct luks2_hdr *hdr, int keyslot, struct crypt_pbkdf_type *pbkdf)
+{
+	json_object *jobj_keyslot, *jobj_kdf, *jobj;
+
+	if (!hdr || !pbkdf)
+		return -EINVAL;
+
+	if (LUKS2_keyslot_info(hdr, keyslot) == CRYPT_SLOT_INVALID)
+		return -EINVAL;
+
+	jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, keyslot);
+	if (!jobj_keyslot)
+		return -ENOENT;
+
+	if (!json_object_object_get_ex(jobj_keyslot, "kdf", &jobj_kdf))
+		return -EINVAL;
+
+	if (!json_object_object_get_ex(jobj_kdf, "type", &jobj))
+		return -EINVAL;
+
+	memset(pbkdf, 0, sizeof(*pbkdf));
+
+	pbkdf->type = json_object_get_string(jobj);
+	if (json_object_object_get_ex(jobj_kdf, "hash", &jobj))
+		pbkdf->hash = json_object_get_string(jobj);
+	if (json_object_object_get_ex(jobj_kdf, "iterations", &jobj))
+		pbkdf->iterations = json_object_get_int(jobj);
+	if (json_object_object_get_ex(jobj_kdf, "time", &jobj))
+		pbkdf->iterations = json_object_get_int(jobj);
+	if (json_object_object_get_ex(jobj_kdf, "memory", &jobj))
+		pbkdf->max_memory_kb = json_object_get_int(jobj);
+	if (json_object_object_get_ex(jobj_kdf, "cpus", &jobj))
+		pbkdf->parallel_threads = json_object_get_int(jobj);
+
+	return 0;
+}
+
+static int LUKS2_keyslot_unbound(struct luks2_hdr *hdr, int keyslot)
+{
+	json_object *jobj_digest, *jobj_segments;
+	int digest = LUKS2_digest_by_keyslot(hdr, keyslot);
+
+	if (digest < 0)
+		return 0;
+
+	if (!(jobj_digest = LUKS2_get_digest_jobj(hdr, digest)))
+		return 0;
+
+	json_object_object_get_ex(jobj_digest, "segments", &jobj_segments);
+	if (!jobj_segments || !json_object_is_type(jobj_segments, json_type_array) ||
+	    json_object_array_length(jobj_segments) == 0)
+		return 1;
+
+	return 0;
+}
+
+crypt_keyslot_info LUKS2_keyslot_info(struct luks2_hdr *hdr, int keyslot)
+{
+	if(keyslot >= LUKS2_KEYSLOTS_MAX || keyslot < 0)
+		return CRYPT_SLOT_INVALID;
+
+	if (!LUKS2_get_keyslot_jobj(hdr, keyslot))
+		return CRYPT_SLOT_INACTIVE;
+
+	if (LUKS2_digest_by_keyslot(hdr, keyslot) < 0 ||
+	    LUKS2_keyslot_unbound(hdr, keyslot))
+		return CRYPT_SLOT_UNBOUND;
+
+	if (LUKS2_keyslot_active_count(hdr, CRYPT_DEFAULT_SEGMENT) == 1 &&
+	    !LUKS2_keyslot_for_segment(hdr, keyslot, CRYPT_DEFAULT_SEGMENT))
+		return CRYPT_SLOT_ACTIVE_LAST;
+
+	return CRYPT_SLOT_ACTIVE;
+}
+
+int LUKS2_keyslot_jobj_area(json_object *jobj_keyslot, uint64_t *offset, uint64_t *length)
+{
+	json_object *jobj_area, *jobj;
+
+	if (!json_object_object_get_ex(jobj_keyslot, "area", &jobj_area))
+		return -EINVAL;
+
+	if (!json_object_object_get_ex(jobj_area, "offset", &jobj))
+		return -EINVAL;
+	*offset = crypt_jobj_get_uint64(jobj);
+
+	if (!json_object_object_get_ex(jobj_area, "size", &jobj))
+		return -EINVAL;
+	*length = crypt_jobj_get_uint64(jobj);
+
+	return 0;
+}
+
+int LUKS2_keyslot_area(struct luks2_hdr *hdr,
+	int keyslot,
+	uint64_t *offset,
+	uint64_t *length)
+{
+	json_object *jobj_keyslot;
+
+	if (LUKS2_keyslot_info(hdr, keyslot) == CRYPT_SLOT_INVALID)
+		return -EINVAL;
+
+	jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, keyslot);
+	if (!jobj_keyslot)
+		return -ENOENT;
+
+	return LUKS2_keyslot_jobj_area(jobj_keyslot, offset, length);
+}
+
+static int _open_and_verify(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	const keyslot_handler *h,
+	int keyslot,
+	const char *password,
+	size_t password_len,
+	struct volume_key **vk)
+{
+	int r, key_size = LUKS2_get_keyslot_stored_key_size(hdr, keyslot);
+
+	if (key_size < 0)
+		return -EINVAL;
+
+	*vk = crypt_alloc_volume_key(key_size, NULL);
+	if (!*vk)
+		return -ENOMEM;
+
+	r = h->open(cd, keyslot, password, password_len, (*vk)->key, (*vk)->keylength);
+	if (r < 0)
+		log_dbg(cd, "Keyslot %d (%s) open failed with %d.", keyslot, h->name, r);
+	else
+		r = LUKS2_digest_verify(cd, hdr, *vk, keyslot);
+
+	if (r < 0) {
+		crypt_free_volume_key(*vk);
+		*vk = NULL;
+	}
+
+	crypt_volume_key_set_id(*vk, r);
+
+	return r < 0 ? r : keyslot;
+}
+
+static int LUKS2_open_and_verify_by_digest(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	int digest,
+	const char *password,
+	size_t password_len,
+	struct volume_key **vk)
+{
+	const keyslot_handler *h;
+	int r;
+
+	if (!(h = LUKS2_keyslot_handler(cd, keyslot)))
+		return -ENOENT;
+
+	r = h->validate(cd, LUKS2_get_keyslot_jobj(hdr, keyslot));
+	if (r) {
+		log_dbg(cd, "Keyslot %d validation failed.", keyslot);
+		return r;
+	}
+
+	r = _keyslot_for_digest(hdr, keyslot, digest);
+	if (r) {
+		if (r == -ENOENT)
+			log_dbg(cd, "Keyslot %d unusable for digest %d.", keyslot, digest);
+		return r;
+	}
+
+	return _open_and_verify(cd, hdr, h, keyslot, password, password_len, vk);
+}
+
+static int LUKS2_open_and_verify(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	int segment,
+	const char *password,
+	size_t password_len,
+	struct volume_key **vk)
+{
+	const keyslot_handler *h;
+	int r;
+
+	if (!(h = LUKS2_keyslot_handler(cd, keyslot)))
+		return -ENOENT;
+
+	r = h->validate(cd, LUKS2_get_keyslot_jobj(hdr, keyslot));
+	if (r) {
+		log_dbg(cd, "Keyslot %d validation failed.", keyslot);
+		return r;
+	}
+
+	r = LUKS2_keyslot_for_segment(hdr, keyslot, segment);
+	if (r) {
+		if (r == -ENOENT)
+			log_dbg(cd, "Keyslot %d unusable for segment %d.", keyslot, segment);
+		return r;
+	}
+
+	return _open_and_verify(cd, hdr, h, keyslot, password, password_len, vk);
+}
+
+static int LUKS2_keyslot_open_priority_digest(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	crypt_keyslot_priority priority,
+	const char *password,
+	size_t password_len,
+	int digest,
+	struct volume_key **vk)
+{
+	json_object *jobj_keyslots, *jobj;
+	crypt_keyslot_priority slot_priority;
+	int keyslot, r = -ENOENT;
+
+	json_object_object_get_ex(hdr->jobj, "keyslots", &jobj_keyslots);
+
+	json_object_object_foreach(jobj_keyslots, slot, val) {
+		if (!json_object_object_get_ex(val, "priority", &jobj))
+			slot_priority = CRYPT_SLOT_PRIORITY_NORMAL;
+		else
+			slot_priority = json_object_get_int(jobj);
+
+		keyslot = atoi(slot);
+		if (slot_priority != priority) {
+			log_dbg(cd, "Keyslot %d priority %d != %d (required), skipped.",
+				keyslot, slot_priority, priority);
+			continue;
+		}
+
+		r = LUKS2_open_and_verify_by_digest(cd, hdr, keyslot, digest, password, password_len, vk);
+
+		/* Do not retry for errors that are no -EPERM or -ENOENT,
+		   former meaning password wrong, latter key slot unusable for segment */
+		if ((r != -EPERM) && (r != -ENOENT))
+			break;
+	}
+
+	return r;
+}
+
+static int LUKS2_keyslot_open_priority(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	crypt_keyslot_priority priority,
+	const char *password,
+	size_t password_len,
+	int segment,
+	struct volume_key **vk)
+{
+	json_object *jobj_keyslots, *jobj;
+	crypt_keyslot_priority slot_priority;
+	int keyslot, r = -ENOENT;
+
+	json_object_object_get_ex(hdr->jobj, "keyslots", &jobj_keyslots);
+
+	json_object_object_foreach(jobj_keyslots, slot, val) {
+		if (!json_object_object_get_ex(val, "priority", &jobj))
+			slot_priority = CRYPT_SLOT_PRIORITY_NORMAL;
+		else
+			slot_priority = json_object_get_int(jobj);
+
+		keyslot = atoi(slot);
+		if (slot_priority != priority) {
+			log_dbg(cd, "Keyslot %d priority %d != %d (required), skipped.",
+				keyslot, slot_priority, priority);
+			continue;
+		}
+
+		r = LUKS2_open_and_verify(cd, hdr, keyslot, segment, password, password_len, vk);
+
+		/* Do not retry for errors that are no -EPERM or -ENOENT,
+		   former meaning password wrong, latter key slot unusable for segment */
+		if ((r != -EPERM) && (r != -ENOENT))
+			break;
+	}
+
+	return r;
+}
+
+static int LUKS2_keyslot_open_by_digest(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	int digest,
+	const char *password,
+	size_t password_len,
+	struct volume_key **vk)
+{
+	int r_prio, r = -EINVAL;
+
+	if (digest < 0)
+		return r;
+
+	if (keyslot == CRYPT_ANY_SLOT) {
+		r_prio = LUKS2_keyslot_open_priority_digest(cd, hdr, CRYPT_SLOT_PRIORITY_PREFER,
+			password, password_len, digest, vk);
+		if (r_prio >= 0)
+			r = r_prio;
+		else if (r_prio != -EPERM && r_prio != -ENOENT)
+			r = r_prio;
+		else
+			r = LUKS2_keyslot_open_priority_digest(cd, hdr, CRYPT_SLOT_PRIORITY_NORMAL,
+				password, password_len, digest, vk);
+		/* Prefer password wrong to no entry from priority slot */
+		if (r_prio == -EPERM && r == -ENOENT)
+			r = r_prio;
+	} else
+		r = LUKS2_open_and_verify_by_digest(cd, hdr, keyslot, digest, password, password_len, vk);
+
+	return r;
+}
+
+int LUKS2_keyslot_open_all_segments(struct crypt_device *cd,
+	int keyslot_old,
+	int keyslot_new,
+	const char *password,
+	size_t password_len,
+	struct volume_key **vks)
+{
+	struct volume_key *vk = NULL;
+	int digest_old, digest_new, r = -EINVAL;
+	struct luks2_hdr *hdr = crypt_get_hdr(cd, CRYPT_LUKS2);
+
+	digest_old = LUKS2_reencrypt_digest_old(hdr);
+	if (digest_old >= 0) {
+		log_dbg(cd, "Trying to unlock volume key (digest: %d) using keyslot %d.", digest_old, keyslot_old);
+		r = LUKS2_keyslot_open_by_digest(cd, hdr, keyslot_old, digest_old, password, password_len, &vk);
+		if (r < 0)
+			goto out;
+		crypt_volume_key_add_next(vks, vk);
+	}
+
+	digest_new = LUKS2_reencrypt_digest_new(hdr);
+	if (digest_new >= 0 && digest_old != digest_new) {
+		log_dbg(cd, "Trying to unlock volume key (digest: %d) using keyslot %d.", digest_new, keyslot_new);
+		r = LUKS2_keyslot_open_by_digest(cd, hdr, keyslot_new, digest_new, password, password_len, &vk);
+		if (r < 0)
+			goto out;
+		crypt_volume_key_add_next(vks, vk);
+	}
+out:
+	if (r < 0) {
+		crypt_free_volume_key(*vks);
+		*vks = NULL;
+
+		if (r == -ENOMEM)
+			log_err(cd, _("Not enough available memory to open a keyslot."));
+		else if (r != -EPERM)
+			log_err(cd, _("Keyslot open failed."));
+	}
+	return r;
+}
+
+int LUKS2_keyslot_open(struct crypt_device *cd,
+	int keyslot,
+	int segment,
+	const char *password,
+	size_t password_len,
+	struct volume_key **vk)
+{
+	struct luks2_hdr *hdr;
+	int r_prio, r = -EINVAL;
+
+	hdr = crypt_get_hdr(cd, CRYPT_LUKS2);
+
+	if (keyslot == CRYPT_ANY_SLOT) {
+		r_prio = LUKS2_keyslot_open_priority(cd, hdr, CRYPT_SLOT_PRIORITY_PREFER,
+			password, password_len, segment, vk);
+		if (r_prio >= 0)
+			r = r_prio;
+		else if (r_prio != -EPERM && r_prio != -ENOENT)
+			r = r_prio;
+		else
+			r = LUKS2_keyslot_open_priority(cd, hdr, CRYPT_SLOT_PRIORITY_NORMAL,
+				password, password_len, segment, vk);
+		/* Prefer password wrong to no entry from priority slot */
+		if (r_prio == -EPERM && r == -ENOENT)
+			r = r_prio;
+	} else
+		r = LUKS2_open_and_verify(cd, hdr, keyslot, segment, password, password_len, vk);
+
+	if (r < 0) {
+		if (r == -ENOMEM)
+			log_err(cd, _("Not enough available memory to open a keyslot."));
+		else if (r != -EPERM)
+			log_err(cd, _("Keyslot open failed."));
+	}
+
+	return r;
+}
+
+int LUKS2_keyslot_reencrypt_allocate(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	const struct crypt_params_reencrypt *params)
+{
+	const keyslot_handler *h;
+	int r;
+
+	if (keyslot == CRYPT_ANY_SLOT)
+		return -EINVAL;
+
+	/* FIXME: find keyslot by type */
+	h = LUKS2_keyslot_handler_type(cd, "reencrypt");
+	if (!h)
+		return -EINVAL;
+
+	r = reenc_keyslot_alloc(cd, hdr, keyslot, params);
+	if (r < 0)
+		return r;
+
+	r = LUKS2_keyslot_priority_set(cd, hdr, keyslot, CRYPT_SLOT_PRIORITY_IGNORE, 0);
+	if (r < 0)
+		return r;
+
+	r = h->validate(cd, LUKS2_get_keyslot_jobj(hdr, keyslot));
+	if (r) {
+		log_dbg(cd, "Keyslot validation failed.");
+		return r;
+	}
+
+	return 0;
+}
+
+int LUKS2_keyslot_reencrypt_store(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	const void *buffer,
+	size_t buffer_length)
+{
+	const keyslot_handler *h;
+	int r;
+
+	if (!(h = LUKS2_keyslot_handler(cd, keyslot)) || strcmp(h->name, "reencrypt"))
+		return -EINVAL;
+
+	r = h->validate(cd, LUKS2_get_keyslot_jobj(hdr, keyslot));
+	if (r) {
+		log_dbg(cd, "Keyslot validation failed.");
+		return r;
+	}
+
+	return h->store(cd, keyslot, NULL, 0,
+			buffer, buffer_length);
+}
+
+int LUKS2_keyslot_store(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	const char *password,
+	size_t password_len,
+	const struct volume_key *vk,
+	const struct luks2_keyslot_params *params)
+{
+	const keyslot_handler *h;
+	int r;
+
+	if (keyslot == CRYPT_ANY_SLOT)
+		return -EINVAL;
+
+	if (!LUKS2_get_keyslot_jobj(hdr, keyslot)) {
+		/* Try to allocate default and empty keyslot type */
+		h = LUKS2_keyslot_handler_type(cd, "luks2");
+		if (!h)
+			return -EINVAL;
+
+		r = h->alloc(cd, keyslot, vk->keylength, params);
+		if (r)
+			return r;
+	} else {
+		if (!(h = LUKS2_keyslot_handler(cd, keyslot)))
+			return -EINVAL;
+
+		r = h->update(cd, keyslot, params);
+		if (r) {
+			log_dbg(cd, "Failed to update keyslot %d json.", keyslot);
+			return r;
+		}
+	}
+
+	r = h->validate(cd, LUKS2_get_keyslot_jobj(hdr, keyslot));
+	if (r) {
+		log_dbg(cd, "Keyslot validation failed.");
+		return r;
+	}
+
+	if (LUKS2_hdr_validate(cd, hdr->jobj, hdr->hdr_size - LUKS2_HDR_BIN_LEN))
+		return -EINVAL;
+
+	return h->store(cd, keyslot, password, password_len,
+			vk->key, vk->keylength);
+}
+
+int LUKS2_keyslot_wipe(struct crypt_device *cd,
+	struct luks2_hdr *hdr,
+	int keyslot,
+	int wipe_area_only)
+{
+	struct device *device = crypt_metadata_device(cd);
+	uint64_t area_offset, area_length;
+	int r;
+	json_object *jobj_keyslot, *jobj_keyslots;
+	const keyslot_handler *h;
+
+	h = LUKS2_keyslot_handler(cd, keyslot);
+
+	if (!json_object_object_get_ex(hdr->jobj, "keyslots", &jobj_keyslots))
+		return -EINVAL;
+
+	jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, keyslot);
+	if (!jobj_keyslot)
+		return -ENOENT;
+
+	if (wipe_area_only)
+		log_dbg(cd, "Wiping keyslot %d area only.", keyslot);
+
+	r = LUKS2_device_write_lock(cd, hdr, device);
+	if (r)
+		return r;
+
+	/* secure deletion of possible key material in keyslot area */
+	r = crypt_keyslot_area(cd, keyslot, &area_offset, &area_length);
+	if (r && r != -ENOENT)
+		goto out;
+
+	if (!r) {
+		r = crypt_wipe_device(cd, device, CRYPT_WIPE_SPECIAL, area_offset,
+			      area_length, area_length, NULL, NULL);
+		if (r) {
+			if (r == -EACCES) {
+				log_err(cd, _("Cannot write to device %s, permission denied."),
+					device_path(device));
+				r = -EINVAL;
+			} else
+				log_err(cd, _("Cannot wipe device %s."), device_path(device));
+			goto out;
+		}
+	}
+
+	if (wipe_area_only)
+		goto out;
+
+	/* Slot specific wipe */
+	if (h) {
+		r = h->wipe(cd, keyslot);
+		if (r < 0)
+			goto out;
+	} else
+		log_dbg(cd, "Wiping keyslot %d without specific-slot handler loaded.", keyslot);
+
+	json_object_object_del_by_uint(jobj_keyslots, keyslot);
+
+	r = LUKS2_hdr_write(cd, hdr);
+out:
+	device_write_unlock(cd, crypt_metadata_device(cd));
+	return r;
+}
+
+int LUKS2_keyslot_dump(struct crypt_device *cd, int keyslot)
+{
+	const keyslot_handler *h;
+
+	if (!(h = LUKS2_keyslot_handler(cd, keyslot)))
+		return -EINVAL;
+
+	return h->dump(cd, keyslot);
+}
+
+crypt_keyslot_priority LUKS2_keyslot_priority_get(struct crypt_device *cd,
+	  struct luks2_hdr *hdr, int keyslot)
+{
+	json_object *jobj_keyslot, *jobj_priority;
+
+	jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, keyslot);
+	if (!jobj_keyslot)
+		return CRYPT_SLOT_PRIORITY_INVALID;
+
+	if (!json_object_object_get_ex(jobj_keyslot, "priority", &jobj_priority))
+		return CRYPT_SLOT_PRIORITY_NORMAL;
+
+	return json_object_get_int(jobj_priority);
+}
+
+int LUKS2_keyslot_priority_set(struct crypt_device *cd, struct luks2_hdr *hdr,
+			       int keyslot, crypt_keyslot_priority priority, int commit)
+{
+	json_object *jobj_keyslot;
+
+	jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, keyslot);
+	if (!jobj_keyslot)
+		return -EINVAL;
+
+	if (priority == CRYPT_SLOT_PRIORITY_NORMAL)
+		json_object_object_del(jobj_keyslot, "priority");
+	else
+		json_object_object_add(jobj_keyslot, "priority", json_object_new_int(priority));
+
+	return commit ? LUKS2_hdr_write(cd, hdr) : 0;
+}
+
+int placeholder_keyslot_alloc(struct crypt_device *cd,
+	int keyslot,
+	uint64_t area_offset,
+	uint64_t area_length,
+	size_t volume_key_len)
+{
+	struct luks2_hdr *hdr;
+	json_object *jobj_keyslots, *jobj_keyslot, *jobj_area;
+
+	log_dbg(cd, "Allocating placeholder keyslot %d for LUKS1 down conversion.", keyslot);
+
+	if (!(hdr = crypt_get_hdr(cd, CRYPT_LUKS2)))
+		return -EINVAL;
+
+	if (keyslot < 0 || keyslot >= LUKS2_KEYSLOTS_MAX)
+		return -EINVAL;
+
+	if (LUKS2_get_keyslot_jobj(hdr, keyslot))
+		return -EINVAL;
+
+	if (!json_object_object_get_ex(hdr->jobj, "keyslots", &jobj_keyslots))
+		return -EINVAL;
+
+	jobj_keyslot = json_object_new_object();
+	json_object_object_add(jobj_keyslot, "type", json_object_new_string("placeholder"));
+	/*
+	 * key_size = -1 makes placeholder keyslot impossible to pass validation.
+	 * It's a safeguard against accidentally storing temporary conversion
+	 * LUKS2 header.
+	 */
+	json_object_object_add(jobj_keyslot, "key_size", json_object_new_int(-1));
+
+	/* Area object */
+	jobj_area = json_object_new_object();
+	json_object_object_add(jobj_area, "offset", crypt_jobj_new_uint64(area_offset));
+	json_object_object_add(jobj_area, "size", crypt_jobj_new_uint64(area_length));
+	json_object_object_add(jobj_keyslot, "area", jobj_area);
+
+	json_object_object_add_by_uint(jobj_keyslots, keyslot, jobj_keyslot);
+
+	return 0;
+}
+
+static unsigned LUKS2_get_keyslot_digests_count(json_object *hdr_jobj, int keyslot)
+{
+	char num[16];
+	json_object *jobj_digests, *jobj_keyslots;
+	unsigned count = 0;
+
+	if (!json_object_object_get_ex(hdr_jobj, "digests", &jobj_digests))
+		return 0;
+
+	if (snprintf(num, sizeof(num), "%u", keyslot) < 0)
+		return 0;
+
+	json_object_object_foreach(jobj_digests, key, val) {
+		UNUSED(key);
+		json_object_object_get_ex(val, "keyslots", &jobj_keyslots);
+		if (LUKS2_array_jobj(jobj_keyslots, num))
+			count++;
+	}
+
+	return count;
+}
+
+/* run only on header that passed basic format validation */
+int LUKS2_keyslots_validate(struct crypt_device *cd, json_object *hdr_jobj)
+{
+	const keyslot_handler *h;
+	int keyslot;
+	json_object *jobj_keyslots, *jobj_type;
+	uint32_t reqs, reencrypt_count = 0;
+	struct luks2_hdr dummy = {
+		.jobj = hdr_jobj
+	};
+
+	if (!json_object_object_get_ex(hdr_jobj, "keyslots", &jobj_keyslots))
+		return -EINVAL;
+
+	if (LUKS2_config_get_requirements(cd, &dummy, &reqs))
+		return -EINVAL;
+
+	json_object_object_foreach(jobj_keyslots, slot, val) {
+		keyslot = atoi(slot);
+		json_object_object_get_ex(val, "type", &jobj_type);
+		h = LUKS2_keyslot_handler_type(cd, json_object_get_string(jobj_type));
+		if (!h)
+			continue;
+		if (h->validate && h->validate(cd, val)) {
+			log_dbg(cd, "Keyslot type %s validation failed on keyslot %d.", h->name, keyslot);
+			return -EINVAL;
+		}
+
+		if (!strcmp(h->name, "luks2") && LUKS2_get_keyslot_digests_count(hdr_jobj, keyslot) != 1) {
+			log_dbg(cd, "Keyslot %d is not assigned to exactly 1 digest.", keyslot);
+			return -EINVAL;
+		}
+
+		if (!strcmp(h->name, "reencrypt"))
+			reencrypt_count++;
+	}
+
+	if ((reqs & CRYPT_REQUIREMENT_ONLINE_REENCRYPT) && reencrypt_count == 0) {
+		log_dbg(cd, "Missing reencryption keyslot.");
+		return -EINVAL;
+	}
+
+	if (!(reqs & CRYPT_REQUIREMENT_ONLINE_REENCRYPT) && reencrypt_count) {
+		log_dbg(cd, "Missing reencryption requirement flag.");
+		return -EINVAL;
+	}
+
+	if (reencrypt_count > 1) {
+		log_dbg(cd, "Too many reencryption keyslots.");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void LUKS2_keyslots_repair(struct crypt_device *cd, json_object *jobj_keyslots)
+{
+	const keyslot_handler *h;
+	json_object *jobj_type;
+
+	json_object_object_foreach(jobj_keyslots, slot, val) {
+		UNUSED(slot);
+		if (!json_object_is_type(val, json_type_object) ||
+		    !json_object_object_get_ex(val, "type", &jobj_type) ||
+		    !json_object_is_type(jobj_type, json_type_string))
+			continue;
+
+		h = LUKS2_keyslot_handler_type(cd, json_object_get_string(jobj_type));
+		if (h && h->repair)
+			h->repair(cd, val);
+	}
+}
+
+/* assumes valid header */
+int LUKS2_find_keyslot(struct luks2_hdr *hdr, const char *type)
+{
+	int i;
+	json_object *jobj_keyslot, *jobj_type;
+
+	if (!type)
+		return -EINVAL;
+
+	for (i = 0; i < LUKS2_KEYSLOTS_MAX; i++) {
+		jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, i);
+		if (!jobj_keyslot)
+			continue;
+
+		json_object_object_get_ex(jobj_keyslot, "type", &jobj_type);
+		if (!strcmp(json_object_get_string(jobj_type), type))
+			return i;
+	}
+
+	return -ENOENT;
+}