/*
* LUKS - Linux Unified Key Setup v2, internal segment handling
*
* Copyright (C) 2018-2020, Red Hat, Inc. All rights reserved.
* Copyright (C) 2018-2020, 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"
/* use only on already validated 'segments' object */
uint64_t json_segments_get_minimal_offset(json_object *jobj_segments, unsigned blockwise)
{
uint64_t tmp, min = blockwise ? UINT64_MAX >> SECTOR_SHIFT : UINT64_MAX;
if (!jobj_segments)
return 0;
json_object_object_foreach(jobj_segments, key, val) {
UNUSED(key);
if (json_segment_is_backup(val))
continue;
tmp = json_segment_get_offset(val, blockwise);
if (!tmp)
return tmp;
if (tmp < min)
min = tmp;
}
return min;
}
uint64_t json_segment_get_offset(json_object *jobj_segment, unsigned blockwise)
{
json_object *jobj;
if (!jobj_segment ||
!json_object_object_get_ex(jobj_segment, "offset", &jobj))
return 0;
return blockwise ? crypt_jobj_get_uint64(jobj) >> SECTOR_SHIFT : crypt_jobj_get_uint64(jobj);
}
const char *json_segment_type(json_object *jobj_segment)
{
json_object *jobj;
if (!jobj_segment ||
!json_object_object_get_ex(jobj_segment, "type", &jobj))
return NULL;
return json_object_get_string(jobj);
}
uint64_t json_segment_get_iv_offset(json_object *jobj_segment)
{
json_object *jobj;
if (!jobj_segment ||
!json_object_object_get_ex(jobj_segment, "iv_tweak", &jobj))
return 0;
return crypt_jobj_get_uint64(jobj);
}
uint64_t json_segment_get_size(json_object *jobj_segment, unsigned blockwise)
{
json_object *jobj;
if (!jobj_segment ||
!json_object_object_get_ex(jobj_segment, "size", &jobj))
return 0;
return blockwise ? crypt_jobj_get_uint64(jobj) >> SECTOR_SHIFT : crypt_jobj_get_uint64(jobj);
}
const char *json_segment_get_cipher(json_object *jobj_segment)
{
json_object *jobj;
/* FIXME: Pseudo "null" cipher should be handled elsewhere */
if (!jobj_segment ||
!json_object_object_get_ex(jobj_segment, "encryption", &jobj))
return "null";
return json_object_get_string(jobj);
}
int json_segment_get_sector_size(json_object *jobj_segment)
{
json_object *jobj;
if (!jobj_segment ||
!json_object_object_get_ex(jobj_segment, "sector_size", &jobj))
return -1;
return json_object_get_int(jobj);
}
static json_object *json_segment_get_flags(json_object *jobj_segment)
{
json_object *jobj;
if (!jobj_segment || !(json_object_object_get_ex(jobj_segment, "flags", &jobj)))
return NULL;
return jobj;
}
static bool json_segment_contains_flag(json_object *jobj_segment, const char *flag_str, size_t len)
{
int r, i;
json_object *jobj, *jobj_flags = json_segment_get_flags(jobj_segment);
if (!jobj_flags)
return false;
for (i = 0; i < (int)json_object_array_length(jobj_flags); i++) {
jobj = json_object_array_get_idx(jobj_flags, i);
if (len)
r = strncmp(json_object_get_string(jobj), flag_str, len);
else
r = strcmp(json_object_get_string(jobj), flag_str);
if (!r)
return true;
}
return false;
}
bool json_segment_is_backup(json_object *jobj_segment)
{
return json_segment_contains_flag(jobj_segment, "backup-", 7);
}
json_object *json_segments_get_segment(json_object *jobj_segments, int segment)
{
json_object *jobj;
char segment_name[16];
if (snprintf(segment_name, sizeof(segment_name), "%u", segment) < 1)
return NULL;
if (!json_object_object_get_ex(jobj_segments, segment_name, &jobj))
return NULL;
return jobj;
}
unsigned json_segments_count(json_object *jobj_segments)
{
unsigned count = 0;
if (!jobj_segments)
return 0;
json_object_object_foreach(jobj_segments, slot, val) {
UNUSED(slot);
if (!json_segment_is_backup(val))
count++;
}
return count;
}
static void _get_segment_or_id_by_flag(json_object *jobj_segments, const char *flag, unsigned id, void *retval)
{
json_object *jobj_flags, **jobj_ret = (json_object **)retval;
int *ret = (int *)retval;
if (!flag)
return;
json_object_object_foreach(jobj_segments, key, value) {
if (!json_object_object_get_ex(value, "flags", &jobj_flags))
continue;
if (LUKS2_array_jobj(jobj_flags, flag)) {
if (id)
*ret = atoi(key);
else
*jobj_ret = value;
return;
}
}
}
void json_segment_remove_flag(json_object *jobj_segment, const char *flag)
{
json_object *jobj_flags, *jobj_flags_new;
if (!jobj_segment)
return;
jobj_flags = json_segment_get_flags(jobj_segment);
if (!jobj_flags)
return;
jobj_flags_new = LUKS2_array_remove(jobj_flags, flag);
if (!jobj_flags_new)
return;
if (json_object_array_length(jobj_flags_new) <= 0) {
json_object_put(jobj_flags_new);
json_object_object_del(jobj_segment, "flags");
} else
json_object_object_add(jobj_segment, "flags", jobj_flags_new);
}
static json_object *_segment_create_generic(const char *type, uint64_t offset, const uint64_t *length)
{
json_object *jobj = json_object_new_object();
if (!jobj)
return NULL;
json_object_object_add(jobj, "type", json_object_new_string(type));
json_object_object_add(jobj, "offset", crypt_jobj_new_uint64(offset));
json_object_object_add(jobj, "size", length ? crypt_jobj_new_uint64(*length) : json_object_new_string("dynamic"));
return jobj;
}
json_object *json_segment_create_linear(uint64_t offset, const uint64_t *length, unsigned reencryption)
{
json_object *jobj = _segment_create_generic("linear", offset, length);
if (reencryption)
LUKS2_segment_set_flag(jobj, "in-reencryption");
return jobj;
}
json_object *json_segment_create_crypt(uint64_t offset,
uint64_t iv_offset, const uint64_t *length,
const char *cipher, uint32_t sector_size,
unsigned reencryption)
{
json_object *jobj = _segment_create_generic("crypt", offset, length);
if (!jobj)
return NULL;
json_object_object_add(jobj, "iv_tweak", crypt_jobj_new_uint64(iv_offset));
json_object_object_add(jobj, "encryption", json_object_new_string(cipher));
json_object_object_add(jobj, "sector_size", json_object_new_int(sector_size));
if (reencryption)
LUKS2_segment_set_flag(jobj, "in-reencryption");
return jobj;
}
uint64_t LUKS2_segment_offset(struct luks2_hdr *hdr, int segment, unsigned blockwise)
{
return json_segment_get_offset(LUKS2_get_segment_jobj(hdr, segment), blockwise);
}
int json_segments_segment_in_reencrypt(json_object *jobj_segments)
{
json_object *jobj_flags;
json_object_object_foreach(jobj_segments, slot, val) {
if (!json_object_object_get_ex(val, "flags", &jobj_flags) ||
!LUKS2_array_jobj(jobj_flags, "in-reencryption"))
continue;
return atoi(slot);
}
return -1;
}
uint64_t LUKS2_segment_size(struct luks2_hdr *hdr, int segment, unsigned blockwise)
{
return json_segment_get_size(LUKS2_get_segment_jobj(hdr, segment), blockwise);
}
int LUKS2_segment_is_type(struct luks2_hdr *hdr, int segment, const char *type)
{
return !strcmp(json_segment_type(LUKS2_get_segment_jobj(hdr, segment)) ?: "", type);
}
int LUKS2_last_segment_by_type(struct luks2_hdr *hdr, const char *type)
{
json_object *jobj_segments;
int last_found = -1;
if (!type)
return -1;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj_segments))
return -1;
json_object_object_foreach(jobj_segments, slot, val) {
if (json_segment_is_backup(val))
continue;
if (strcmp(type, json_segment_type(val) ?: ""))
continue;
if (atoi(slot) > last_found)
last_found = atoi(slot);
}
return last_found;
}
int LUKS2_segment_by_type(struct luks2_hdr *hdr, const char *type)
{
json_object *jobj_segments;
int first_found = -1;
if (!type)
return -EINVAL;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj_segments))
return -EINVAL;
json_object_object_foreach(jobj_segments, slot, val) {
if (json_segment_is_backup(val))
continue;
if (strcmp(type, json_segment_type(val) ?: ""))
continue;
if (first_found < 0)
first_found = atoi(slot);
else if (atoi(slot) < first_found)
first_found = atoi(slot);
}
return first_found;
}
int LUKS2_segment_first_unused_id(struct luks2_hdr *hdr)
{
json_object *jobj_segments;
int id, last_id = -1;
if (!json_object_object_get_ex(hdr->jobj, "segments", &jobj_segments))
return -EINVAL;
json_object_object_foreach(jobj_segments, slot, val) {
UNUSED(val);
id = atoi(slot);
if (id > last_id)
last_id = id;
}
return last_id + 1;
}
int LUKS2_segment_set_flag(json_object *jobj_segment, const char *flag)
{
json_object *jobj_flags;
if (!jobj_segment || !flag)
return -EINVAL;
if (!json_object_object_get_ex(jobj_segment, "flags", &jobj_flags)) {
jobj_flags = json_object_new_array();
if (!jobj_flags)
return -ENOMEM;
json_object_object_add(jobj_segment, "flags", jobj_flags);
}
if (LUKS2_array_jobj(jobj_flags, flag))
return 0;
json_object_array_add(jobj_flags, json_object_new_string(flag));
return 0;
}
int LUKS2_segments_set(struct crypt_device *cd, struct luks2_hdr *hdr,
json_object *jobj_segments, int commit)
{
json_object_object_add(hdr->jobj, "segments", jobj_segments);
return commit ? LUKS2_hdr_write(cd, hdr) : 0;
}
int LUKS2_get_segment_id_by_flag(struct luks2_hdr *hdr, const char *flag)
{
int ret = -ENOENT;
json_object *jobj_segments = LUKS2_get_segments_jobj(hdr);
if (jobj_segments)
_get_segment_or_id_by_flag(jobj_segments, flag, 1, &ret);
return ret;
}
json_object *LUKS2_get_segment_by_flag(struct luks2_hdr *hdr, const char *flag)
{
json_object *jobj_segment = NULL,
*jobj_segments = LUKS2_get_segments_jobj(hdr);
if (jobj_segments)
_get_segment_or_id_by_flag(jobj_segments, flag, 0, &jobj_segment);
return jobj_segment;
}