/*
* LUKS - Linux Unified Key Setup v2, reencryption keyslot handler
*
* Copyright (C) 2016-2020, Red Hat, Inc. All rights reserved.
* Copyright (C) 2016-2020, Ondrej Kozina
*
* 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"
static int reenc_keyslot_open(struct crypt_device *cd,
int keyslot,
const char *password,
size_t password_len,
char *volume_key,
size_t volume_key_len)
{
return -ENOENT;
}
int reenc_keyslot_alloc(struct crypt_device *cd,
struct luks2_hdr *hdr,
int keyslot,
const struct crypt_params_reencrypt *params)
{
int r;
json_object *jobj_keyslots, *jobj_keyslot, *jobj_area;
uint64_t area_offset, area_length;
log_dbg(cd, "Allocating reencrypt keyslot %d.", keyslot);
if (keyslot < 0 || keyslot >= LUKS2_KEYSLOTS_MAX)
return -ENOMEM;
if (!json_object_object_get_ex(hdr->jobj, "keyslots", &jobj_keyslots))
return -EINVAL;
/* encryption doesn't require area (we shift data and backup will be available) */
if (!params->data_shift) {
r = LUKS2_find_area_max_gap(cd, hdr, &area_offset, &area_length);
if (r < 0)
return r;
} else { /* we can't have keyslot w/o area...bug? */
r = LUKS2_find_area_gap(cd, hdr, 1, &area_offset, &area_length);
if (r < 0)
return r;
}
jobj_keyslot = json_object_new_object();
if (!jobj_keyslot)
return -ENOMEM;
jobj_area = json_object_new_object();
if (params->data_shift) {
json_object_object_add(jobj_area, "type", json_object_new_string("datashift"));
json_object_object_add(jobj_area, "shift_size", crypt_jobj_new_uint64(params->data_shift << SECTOR_SHIFT));
} else
/* except data shift protection, initial setting is irrelevant. Type can be changed during reencryption */
json_object_object_add(jobj_area, "type", json_object_new_string("none"));
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, "type", json_object_new_string("reencrypt"));
json_object_object_add(jobj_keyslot, "key_size", json_object_new_int(1)); /* useless but mandatory */
json_object_object_add(jobj_keyslot, "mode", json_object_new_string(crypt_reencrypt_mode_to_str(params->mode)));
if (params->direction == CRYPT_REENCRYPT_FORWARD)
json_object_object_add(jobj_keyslot, "direction", json_object_new_string("forward"));
else if (params->direction == CRYPT_REENCRYPT_BACKWARD)
json_object_object_add(jobj_keyslot, "direction", json_object_new_string("backward"));
else
return -EINVAL;
json_object_object_add(jobj_keyslot, "area", jobj_area);
json_object_object_add_by_uint(jobj_keyslots, keyslot, jobj_keyslot);
if (LUKS2_check_json_size(cd, hdr)) {
log_dbg(cd, "New keyslot too large to fit in free metadata space.");
json_object_object_del_by_uint(jobj_keyslots, keyslot);
return -ENOSPC;
}
JSON_DBG(cd, hdr->jobj, "JSON:");
return 0;
}
static int reenc_keyslot_store_data(struct crypt_device *cd,
json_object *jobj_keyslot,
const void *buffer, size_t buffer_len)
{
int devfd, r;
json_object *jobj_area, *jobj_offset, *jobj_length;
uint64_t area_offset, area_length;
struct device *device = crypt_metadata_device(cd);
if (!json_object_object_get_ex(jobj_keyslot, "area", &jobj_area) ||
!json_object_object_get_ex(jobj_area, "offset", &jobj_offset) ||
!json_object_object_get_ex(jobj_area, "size", &jobj_length))
return -EINVAL;
area_offset = crypt_jobj_get_uint64(jobj_offset);
area_length = crypt_jobj_get_uint64(jobj_length);
if (!area_offset || !area_length || ((uint64_t)buffer_len > area_length))
return -EINVAL;
devfd = device_open_locked(cd, device, O_RDWR);
if (devfd >= 0) {
if (write_lseek_blockwise(devfd, device_block_size(cd, device),
device_alignment(device), CONST_CAST(void *)buffer,
buffer_len, area_offset) < 0)
r = -EIO;
else
r = 0;
} else
r = -EINVAL;
if (r)
log_err(cd, _("IO error while encrypting keyslot."));
return r;
}
static int reenc_keyslot_store(struct crypt_device *cd,
int keyslot,
const char *password __attribute__((unused)),
size_t password_len __attribute__((unused)),
const char *buffer,
size_t buffer_len)
{
struct luks2_hdr *hdr;
json_object *jobj_keyslot;
int r = 0;
if (!cd || !buffer || !buffer_len)
return -EINVAL;
if (!(hdr = crypt_get_hdr(cd, CRYPT_LUKS2)))
return -EINVAL;
log_dbg(cd, "Reencrypt keyslot %d store.", keyslot);
jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, keyslot);
if (!jobj_keyslot)
return -EINVAL;
r = LUKS2_device_write_lock(cd, hdr, crypt_metadata_device(cd));
if (r)
return r;
r = reenc_keyslot_store_data(cd, jobj_keyslot, buffer, buffer_len);
if (r < 0) {
device_write_unlock(cd, crypt_metadata_device(cd));
return r;
}
r = LUKS2_hdr_write(cd, hdr);
device_write_unlock(cd, crypt_metadata_device(cd));
return r < 0 ? r : keyslot;
}
int reenc_keyslot_update(struct crypt_device *cd,
const struct luks2_reenc_context *rh)
{
json_object *jobj_keyslot, *jobj_area, *jobj_area_type;
struct luks2_hdr *hdr;
if (!(hdr = crypt_get_hdr(cd, CRYPT_LUKS2)))
return -EINVAL;
jobj_keyslot = LUKS2_get_keyslot_jobj(hdr, rh->reenc_keyslot);
if (!jobj_keyslot)
return -EINVAL;
json_object_object_get_ex(jobj_keyslot, "area", &jobj_area);
json_object_object_get_ex(jobj_area, "type", &jobj_area_type);
if (rh->rp.type == REENC_PROTECTION_CHECKSUM) {
log_dbg(cd, "Updating reencrypt keyslot for checksum protection.");
json_object_object_add(jobj_area, "type", json_object_new_string("checksum"));
json_object_object_add(jobj_area, "hash", json_object_new_string(rh->rp.p.csum.hash));
json_object_object_add(jobj_area, "sector_size", json_object_new_int64(rh->alignment));
} else if (rh->rp.type == REENC_PROTECTION_NONE) {
log_dbg(cd, "Updating reencrypt keyslot for none protection.");
json_object_object_add(jobj_area, "type", json_object_new_string("none"));
json_object_object_del(jobj_area, "hash");
} else if (rh->rp.type == REENC_PROTECTION_JOURNAL) {
log_dbg(cd, "Updating reencrypt keyslot for journal protection.");
json_object_object_add(jobj_area, "type", json_object_new_string("journal"));
json_object_object_del(jobj_area, "hash");
} else
log_dbg(cd, "No update of reencrypt keyslot needed.");
return 0;
}
static int reenc_keyslot_wipe(struct crypt_device *cd, int keyslot)
{
return 0;
}
static int reenc_keyslot_dump(struct crypt_device *cd, int keyslot)
{
json_object *jobj_keyslot, *jobj_area, *jobj_direction, *jobj_mode, *jobj_resilience,
*jobj1;
jobj_keyslot = LUKS2_get_keyslot_jobj(crypt_get_hdr(cd, CRYPT_LUKS2), keyslot);
if (!jobj_keyslot)
return -EINVAL;
if (!json_object_object_get_ex(jobj_keyslot, "direction", &jobj_direction) ||
!json_object_object_get_ex(jobj_keyslot, "mode", &jobj_mode) ||
!json_object_object_get_ex(jobj_keyslot, "area", &jobj_area) ||
!json_object_object_get_ex(jobj_area, "type", &jobj_resilience))
return -EINVAL;
log_std(cd, "\t%-12s%s\n", "Mode:", json_object_get_string(jobj_mode));
log_std(cd, "\t%-12s%s\n", "Direction:", json_object_get_string(jobj_direction));
log_std(cd, "\t%-12s%s\n", "Resilience:", json_object_get_string(jobj_resilience));
if (!strcmp(json_object_get_string(jobj_resilience), "checksum")) {
json_object_object_get_ex(jobj_area, "hash", &jobj1);
log_std(cd, "\t%-12s%s\n", "Hash:", json_object_get_string(jobj1));
json_object_object_get_ex(jobj_area, "sector_size", &jobj1);
log_std(cd, "\t%-12s%d [bytes]\n", "Hash data:", json_object_get_int(jobj1));
} else if (!strcmp(json_object_get_string(jobj_resilience), "datashift")) {
json_object_object_get_ex(jobj_area, "shift_size", &jobj1);
log_std(cd, "\t%-12s%" PRIu64 "[bytes]\n", "Shift size:", crypt_jobj_get_uint64(jobj1));
}
json_object_object_get_ex(jobj_area, "offset", &jobj1);
log_std(cd, "\tArea offset:%" PRIu64 " [bytes]\n", crypt_jobj_get_uint64(jobj1));
json_object_object_get_ex(jobj_area, "size", &jobj1);
log_std(cd, "\tArea length:%" PRIu64 " [bytes]\n", crypt_jobj_get_uint64(jobj1));
return 0;
}
static int reenc_keyslot_validate(struct crypt_device *cd, json_object *jobj_keyslot)
{
json_object *jobj_mode, *jobj_area, *jobj_type, *jobj_shift_size, *jobj_hash, *jobj_sector_size, *jobj_direction;
const char *mode, *type, *direction;
uint32_t sector_size;
uint64_t shift_size;
/* mode (string: encrypt,reencrypt,decrypt)
* direction (string:)
* area {
* type: (string: datashift, journal, checksum, none)
* hash: (string: checksum only)
* sector_size (uint32: checksum only)
* shift_size (uint64: datashift only)
* }
*/
/* area and area type are validated in general validation code */
if (!jobj_keyslot || !json_object_object_get_ex(jobj_keyslot, "area", &jobj_area) ||
!json_object_object_get_ex(jobj_area, "type", &jobj_type))
return -EINVAL;
jobj_mode = json_contains(cd, jobj_keyslot, "", "reencrypt keyslot", "mode", json_type_string);
jobj_direction = json_contains(cd, jobj_keyslot, "", "reencrypt keyslot", "direction", json_type_string);
if (!jobj_mode || !jobj_direction)
return -EINVAL;
mode = json_object_get_string(jobj_mode);
type = json_object_get_string(jobj_type);
direction = json_object_get_string(jobj_direction);
if (strcmp(mode, "reencrypt") && strcmp(mode, "encrypt") &&
strcmp(mode, "decrypt")) {
log_dbg(cd, "Illegal reencrypt mode %s.", mode);
return -EINVAL;
}
if (strcmp(direction, "forward") && strcmp(direction, "backward")) {
log_dbg(cd, "Illegal reencrypt direction %s.", direction);
return -EINVAL;
}
if (!strcmp(type, "checksum")) {
jobj_hash = json_contains(cd, jobj_area, "type:checksum", "Keyslot area", "hash", json_type_string);
jobj_sector_size = json_contains(cd, jobj_area, "type:checksum", "Keyslot area", "sector_size", json_type_int);
if (!jobj_hash || !jobj_sector_size)
return -EINVAL;
if (!validate_json_uint32(jobj_sector_size))
return -EINVAL;
sector_size = crypt_jobj_get_uint32(jobj_sector_size);
if (sector_size < SECTOR_SIZE || NOTPOW2(sector_size)) {
log_dbg(cd, "Invalid sector_size (%" PRIu32 ") for checksum resilience mode.", sector_size);
return -EINVAL;
}
} else if (!strcmp(type, "datashift")) {
if (!(jobj_shift_size = json_contains(cd, jobj_area, "type:datashift", "Keyslot area", "shift_size", json_type_string)))
return -EINVAL;
shift_size = crypt_jobj_get_uint64(jobj_shift_size);
if (!shift_size)
return -EINVAL;
if (MISALIGNED_512(shift_size)) {
log_dbg(cd, "Shift size field has to be aligned to sector size: %" PRIu32, SECTOR_SIZE);
return -EINVAL;
}
}
return 0;
}
const keyslot_handler reenc_keyslot = {
.name = "reencrypt",
.open = reenc_keyslot_open,
.store = reenc_keyslot_store, /* initialization only or also per every chunk write */
.wipe = reenc_keyslot_wipe,
.dump = reenc_keyslot_dump,
.validate = reenc_keyslot_validate
};