Exemplo n.º 1
0
/* Try to open a particular key slot */
static int LUKS_open_key(unsigned int keyIndex,
		  const char *password,
		  size_t passwordLen,
		  struct luks_phdr *hdr,
		  struct volume_key *vk,
		  struct crypt_device *ctx)
{
	crypt_keyslot_info ki = LUKS_keyslot_info(hdr, keyIndex);
	struct volume_key *derived_key;
	char *AfKey;
	size_t AFEKSize;
	int r;

	log_dbg("Trying to open key slot %d [%s].", keyIndex,
		dbg_slot_state(ki));

	if (ki < CRYPT_SLOT_ACTIVE)
		return -ENOENT;

	derived_key = crypt_alloc_volume_key(hdr->keyBytes, NULL);
	if (!derived_key)
		return -ENOMEM;

	assert(vk->keylength == hdr->keyBytes);
	AFEKSize = AF_split_sectors(vk->keylength, hdr->keyblock[keyIndex].stripes) * SECTOR_SIZE;
	AfKey = crypt_safe_alloc(AFEKSize);
	if (!AfKey) {
		r = -ENOMEM;
		goto out;
	}

	r = crypt_pbkdf("pbkdf2", hdr->hashSpec, password, passwordLen,
			hdr->keyblock[keyIndex].passwordSalt, LUKS_SALTSIZE,
			derived_key->key, hdr->keyBytes,
			hdr->keyblock[keyIndex].passwordIterations);
	if (r < 0)
		goto out;

	log_dbg("Reading key slot %d area.", keyIndex);
	r = LUKS_decrypt_from_storage(AfKey,
				      AFEKSize,
				      hdr->cipherName, hdr->cipherMode,
				      derived_key,
				      hdr->keyblock[keyIndex].keyMaterialOffset,
				      ctx);
	if (r < 0)
		goto out;

	r = AF_merge(AfKey,vk->key,vk->keylength,hdr->keyblock[keyIndex].stripes,hdr->hashSpec);
	if (r < 0)
		goto out;

	r = LUKS_verify_volume_key(hdr, vk);
	if (!r)
		log_verbose(ctx, _("Key slot %d unlocked.\n"), keyIndex);
out:
	crypt_safe_free(AfKey);
	crypt_free_volume_key(derived_key);
	return r;
}
Exemplo n.º 2
0
/* Check that kernel supports requested cipher by decryption of one sector */
static int LUKS_check_cipher(struct luks_phdr *hdr, struct crypt_device *ctx)
{
	int r;
	struct volume_key *empty_key;
	char buf[SECTOR_SIZE];

	log_dbg("Checking if cipher %s-%s is usable.", hdr->cipherName, hdr->cipherMode);

	empty_key = crypt_alloc_volume_key(hdr->keyBytes, NULL);
	if (!empty_key)
		return -ENOMEM;

	r = LUKS_decrypt_from_storage(buf, sizeof(buf),
				      hdr->cipherName, hdr->cipherMode,
				      empty_key, 0, ctx);

	crypt_free_volume_key(empty_key);
	crypt_memzero(buf, sizeof(buf));
	return r;
}
Exemplo n.º 3
0
/* Check that kernel supports requested cipher by decryption of one sector */
int LUKS_check_cipher(struct crypt_device *ctx, size_t keylength, const char *cipher, const char *cipher_mode)
{
	int r;
	struct volume_key *empty_key;
	char buf[SECTOR_SIZE];

	log_dbg("Checking if cipher %s-%s is usable.", cipher, cipher_mode);

	empty_key = crypt_alloc_volume_key(keylength, NULL);
	if (!empty_key)
		return -ENOMEM;

	/* No need to get KEY quality random but it must avoid known weak keys. */
	r = crypt_random_get(ctx, empty_key->key, empty_key->keylength, CRYPT_RND_NORMAL);
	if (!r)
		r = LUKS_decrypt_from_storage(buf, sizeof(buf), cipher, cipher_mode, empty_key, 0, ctx);

	crypt_free_volume_key(empty_key);
	crypt_memzero(buf, sizeof(buf));
	return r;
}
Exemplo n.º 4
0
int decryptFromStorage(
	char *dst, size_t dstLength,
	const char *cipher,
	const char *cipher_mode,
	const char *vkey, size_t vkLength,
	unsigned int sector,
	struct crypt_device *ctx)
{
	struct volume_key* vk = malloc(sizeof(struct volume_key) + vkLength);
	vk->keylength = vkLength;
	memcpy(&vk->key, vkey, vkLength);

	const int r = LUKS_decrypt_from_storage
	(
		dst,		dstLength,
		cipher,		cipher_mode,
		vk,
		sector,
		ctx
	);
	free(vk);

	return r;
}