1/*
2 * prng.h
3 *
4 * pseudorandom source
5 *
6 * David A. McGrew
7 * Cisco Systems, Inc.
8 */
9/*
10 *
11 * Copyright (c) 2001-2006, Cisco Systems, Inc.
12 * All rights reserved.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 *
18 *   Redistributions of source code must retain the above copyright
19 *   notice, this list of conditions and the following disclaimer.
20 *
21 *   Redistributions in binary form must reproduce the above
22 *   copyright notice, this list of conditions and the following
23 *   disclaimer in the documentation and/or other materials provided
24 *   with the distribution.
25 *
26 *   Neither the name of the Cisco Systems, Inc. nor the names of its
27 *   contributors may be used to endorse or promote products derived
28 *   from this software without specific prior written permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
31 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
32 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
33 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
34 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
35 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
36 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
37 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
40 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
41 * OF THE POSSIBILITY OF SUCH DAMAGE.
42 *
43 */
44
45#ifndef PRNG_H
46#define PRNG_H
47
48#include "rand_source.h"  /* for rand_source_func_t definition       */
49#include "aes.h"          /* for aes                                 */
50#include "aes_icm.h"      /* for aes ctr                             */
51
52#define MAX_PRNG_OUT_LEN 0xffffffffU
53
54/*
55 * x917_prng is an ANSI X9.17-like AES-based PRNG
56 */
57
58typedef struct {
59  v128_t   state;          /* state data                              */
60  aes_expanded_key_t key;  /* secret key                              */
61  uint32_t octet_count;    /* number of octets output since last init */
62  rand_source_func_t rand; /* random source for re-initialization     */
63} x917_prng_t;
64
65err_status_t
66x917_prng_init(rand_source_func_t random_source);
67
68err_status_t
69x917_prng_get_octet_string(uint8_t *dest, uint32_t len);
70
71
72/*
73 * ctr_prng is an AES-CTR based PRNG
74 */
75
76typedef struct {
77  uint32_t octet_count;    /* number of octets output since last init */
78  aes_icm_ctx_t   state;   /* state data                              */
79  rand_source_func_t rand; /* random source for re-initialization     */
80} ctr_prng_t;
81
82err_status_t
83ctr_prng_init(rand_source_func_t random_source);
84
85err_status_t
86ctr_prng_get_octet_string(void *dest, uint32_t len);
87
88
89#endif
90