michael@0: /*
michael@0:  * prng.h
michael@0:  *
michael@0:  * pseudorandom source
michael@0:  *
michael@0:  * David A. McGrew
michael@0:  * Cisco Systems, Inc.
michael@0:  */
michael@0: /*
michael@0:  *	
michael@0:  * Copyright (c) 2001-2006, Cisco Systems, Inc.
michael@0:  * All rights reserved.
michael@0:  * 
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 
michael@0:  *   Redistributions of source code must retain the above copyright
michael@0:  *   notice, this list of conditions and the following disclaimer.
michael@0:  * 
michael@0:  *   Redistributions in binary form must reproduce the above
michael@0:  *   copyright notice, this list of conditions and the following
michael@0:  *   disclaimer in the documentation and/or other materials provided
michael@0:  *   with the distribution.
michael@0:  * 
michael@0:  *   Neither the name of the Cisco Systems, Inc. nor the names of its
michael@0:  *   contributors may be used to endorse or promote products derived
michael@0:  *   from this software without specific prior written permission.
michael@0:  * 
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
michael@0:  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
michael@0:  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
michael@0:  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
michael@0:  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
michael@0:  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
michael@0:  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
michael@0:  * OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: #ifndef PRNG_H
michael@0: #define PRNG_H
michael@0: 
michael@0: #include "rand_source.h"  /* for rand_source_func_t definition       */
michael@0: #include "aes.h"          /* for aes                                 */
michael@0: #include "aes_icm.h"      /* for aes ctr                             */
michael@0: 
michael@0: #define MAX_PRNG_OUT_LEN 0xffffffffU
michael@0: 
michael@0: /*
michael@0:  * x917_prng is an ANSI X9.17-like AES-based PRNG
michael@0:  */
michael@0: 
michael@0: typedef struct {
michael@0:   v128_t   state;          /* state data                              */
michael@0:   aes_expanded_key_t key;  /* secret key                              */
michael@0:   uint32_t octet_count;    /* number of octets output since last init */
michael@0:   rand_source_func_t rand; /* random source for re-initialization     */
michael@0: } x917_prng_t;
michael@0: 
michael@0: err_status_t
michael@0: x917_prng_init(rand_source_func_t random_source);
michael@0: 
michael@0: err_status_t
michael@0: x917_prng_get_octet_string(uint8_t *dest, uint32_t len);
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * ctr_prng is an AES-CTR based PRNG
michael@0:  */
michael@0: 
michael@0: typedef struct {
michael@0:   uint32_t octet_count;    /* number of octets output since last init */
michael@0:   aes_icm_ctx_t   state;   /* state data                              */
michael@0:   rand_source_func_t rand; /* random source for re-initialization     */
michael@0: } ctr_prng_t;
michael@0: 
michael@0: err_status_t
michael@0: ctr_prng_init(rand_source_func_t random_source);
michael@0: 
michael@0: err_status_t
michael@0: ctr_prng_get_octet_string(void *dest, uint32_t len);
michael@0: 
michael@0: 
michael@0: #endif