/*
* cryptsetup volume key implementation
*
* Copyright (C) 2004-2006 Clemens Fruhwirth <clemens@endorphin.org>
* Copyright (C) 2010-2020 Red Hat, Inc. All rights reserved.
*
* 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 <string.h>
#include <stdint.h>
#include <stdlib.h>
#include <errno.h>
#include "internal.h"
struct volume_key *crypt_alloc_volume_key(size_t keylength, const char *key)
{
struct volume_key *vk;
if (keylength > (SIZE_MAX - sizeof(*vk)))
return NULL;
vk = malloc(sizeof(*vk) + keylength);
if (!vk)
return NULL;
vk->key_description = NULL;
vk->keylength = keylength;
vk->id = -1;
vk->next = NULL;
/* keylength 0 is valid => no key */
if (vk->keylength) {
if (key)
memcpy(&vk->key, key, keylength);
else
crypt_safe_memzero(&vk->key, keylength);
}
return vk;
}
int crypt_volume_key_set_description(struct volume_key *vk, const char *key_description)
{
if (!vk)
return -EINVAL;
free(CONST_CAST(void*)vk->key_description);
vk->key_description = NULL;
if (key_description && !(vk->key_description = strdup(key_description)))
return -ENOMEM;
return 0;
}
void crypt_volume_key_set_id(struct volume_key *vk, int id)
{
if (vk && id >= 0)
vk->id = id;
}
int crypt_volume_key_get_id(const struct volume_key *vk)
{
return vk ? vk->id : -1;
}
struct volume_key *crypt_volume_key_by_id(struct volume_key *vks, int id)
{
struct volume_key *vk = vks;
if (id < 0)
return NULL;
while (vk && vk->id != id)
vk = vk->next;
return vk;
}
void crypt_volume_key_add_next(struct volume_key **vks, struct volume_key *vk)
{
struct volume_key *tmp;
if (!vks)
return;
if (!*vks) {
*vks = vk;
return;
}
tmp = *vks;
while (tmp->next)
tmp = tmp->next;
tmp->next = vk;
}
struct volume_key *crypt_volume_key_next(struct volume_key *vk)
{
return vk ? vk->next : NULL;
}
void crypt_free_volume_key(struct volume_key *vk)
{
struct volume_key *vk_next;
while (vk) {
crypt_safe_memzero(vk->key, vk->keylength);
vk->keylength = 0;
free(CONST_CAST(void*)vk->key_description);
vk_next = vk->next;
free(vk);
vk = vk_next;
}
}
struct volume_key *crypt_generate_volume_key(struct crypt_device *cd, size_t keylength)
{
int r;
struct volume_key *vk;
vk = crypt_alloc_volume_key(keylength, NULL);
if (!vk)
return NULL;
r = crypt_random_get(cd, vk->key, keylength, CRYPT_RND_KEY);
if(r < 0) {
crypt_free_volume_key(vk);
return NULL;
}
return vk;
}