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 58 typedef 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 65 err_status_t 66 x917_prng_init(rand_source_func_t random_source); 67 68 err_status_t 69 x917_prng_get_octet_string(uint8_t *dest, uint32_t len); 70 71 72 /* 73 * ctr_prng is an AES-CTR based PRNG 74 */ 75 76 typedef 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 82 err_status_t 83 ctr_prng_init(rand_source_func_t random_source); 84 85 err_status_t 86 ctr_prng_get_octet_string(void *dest, uint32_t len); 87 88 89 #endif 90
