linux-imx

/*

 * DRBG: Deterministic Random Bits Generator

 *       Based on NIST Recommended DRBG from NIST SP800-90A with the following

 *       properties:

 *      * CTR DRBG with DF with AES-128, AES-192, AES-256 cores

 *      * Hash DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores

 *      * HMAC DRBG with DF with SHA-1, SHA-256, SHA-384, SHA-512 cores

 *      * with and without prediction resistance

 *

 * Copyright Stephan Mueller <smueller@chronox.de>, 2014

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, and the entire permission notice in its entirety,

 *    including the disclaimer of warranties.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. The name of the author may not be used to endorse or promote

 *    products derived from this software without specific prior

 *    written permission.

 *

 * ALTERNATIVELY, this product may be distributed under the terms of

 * the GNU General Public License, in which case the provisions of the GPL are

 * required INSTEAD OF the above restrictions.  (This clause is

 * necessary due to a potential bad interaction between the GPL and

 * the restrictions contained in a BSD-style copyright.)

 *

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED

 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES

 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF

 * WHICH ARE HEREBY DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE

 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT

 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR

 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE

 * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 * DRBG Usage

 * ==========

 * The SP 800-90A DRBG allows the user to specify a personalization string

 * for initialization as well as an additional information string for each

 * random number request. The following code fragments show how a caller

 * uses the kernel crypto API to use the full functionality of the DRBG.

 *

 * Usage without any additional data

 * ---------------------------------

 * struct crypto_rng *drng;

 * int err;

 * char data[DATALEN];

 *

 * drng = crypto_alloc_rng(drng_name, 0, 0);

 * err = crypto_rng_get_bytes(drng, &data, DATALEN);

 * crypto_free_rng(drng);

 *

 *

 * Usage with personalization string during initialization

 * -------------------------------------------------------