dm-crypt.c

}

/* Message interface
 *	key set <key>
 *	key wipe
 */
static int crypt_message(struct dm_target *ti, unsigned argc, char **argv)
{
	struct crypt_config *cc = ti->private;
	int ret = -EINVAL;

	if (argc < 2)
		goto error;

	if (!strcasecmp(argv[0], "key")) {
		if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
			DMWARN("not suspended during key manipulation.");
			return -EINVAL;
		}
		if (argc == 3 && !strcasecmp(argv[1], "set")) {
			ret = crypt_set_key(cc, argv[2]);
			if (ret)
				return ret;
			if (cc->iv_gen_ops && cc->iv_gen_ops->init)
				ret = cc->iv_gen_ops->init(cc);
			return ret;
		}
		if (argc == 2 && !strcasecmp(argv[1], "wipe")) {
			if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
				ret = cc->iv_gen_ops->wipe(cc);
				if (ret)
					return ret;
			}
			return crypt_wipe_key(cc);
		}
	}

error:
	DMWARN("unrecognised message received.");
	return -EINVAL;
}

static int crypt_iterate_devices(struct dm_target *ti,
				 iterate_devices_callout_fn fn, void *data)
{
	struct crypt_config *cc = ti->private;

	return fn(ti, cc->dev, cc->start, ti->len, data);
}

static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
	/*
	 * Unfortunate constraint that is required to avoid the potential
	 * for exceeding underlying device's max_segments limits -- due to
	 * crypt_alloc_buffer() possibly allocating pages for the encryption
	 * bio that are not as physically contiguous as the original bio.
	 */
	limits->max_segment_size = PAGE_SIZE;
}

static struct target_type crypt_target = {
	.name   = "crypt",
	.version = {1, 14, 1},
	.module = THIS_MODULE,
	.ctr    = crypt_ctr,
	.dtr    = crypt_dtr,
	.map    = crypt_map,
	.status = crypt_status,
	.postsuspend = crypt_postsuspend,
	.preresume = crypt_preresume,
	.resume = crypt_resume,
	.message = crypt_message,
	.iterate_devices = crypt_iterate_devices,
	.io_hints = crypt_io_hints,
};

static int __init dm_crypt_init(void)
{
	int r;

	r = dm_register_target(&crypt_target);
	if (r < 0)
		DMERR("register failed %d", r);

	return r;
}

static void __exit dm_crypt_exit(void)
{
	dm_unregister_target(&crypt_target);
}

module_init(dm_crypt_init);
module_exit(dm_crypt_exit);

MODULE_AUTHOR("Jana Saout <jana@saout.de>");
MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
MODULE_LICENSE("GPL");