1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2001-2007, Tom St Denis 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright notice, 10 * this list of conditions and the following disclaimer. 11 * 12 * 2. Redistributions in binary form must reproduce the above copyright notice, 13 * this list of conditions and the following disclaimer in the documentation 14 * and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* LibTomCrypt, modular cryptographic library -- Tom St Denis 30 * 31 * LibTomCrypt is a library that provides various cryptographic 32 * algorithms in a highly modular and flexible manner. 33 * 34 * The library is free for all purposes without any express 35 * guarantee it works. 36 * 37 * Tom St Denis, tomstdenis@gmail.com, http://libtom.org 38 */ 39 #include "tomcrypt.h" 40 41 /** 42 @file sprng.c 43 Secure PRNG, Tom St Denis 44 */ 45 46 /* A secure PRNG using the RNG functions. Basically this is a 47 * wrapper that allows you to use a secure RNG as a PRNG 48 * in the various other functions. 49 */ 50 51 #ifdef LTC_SPRNG 52 53 const struct ltc_prng_descriptor sprng_desc = 54 { 55 "sprng", 0, 56 &sprng_start, 57 &sprng_add_entropy, 58 &sprng_ready, 59 &sprng_read, 60 &sprng_done, 61 &sprng_export, 62 &sprng_import, 63 &sprng_test 64 }; 65 66 /** 67 Start the PRNG 68 @param prng [out] The PRNG state to initialize 69 @return CRYPT_OK if successful 70 */ 71 int sprng_start(prng_state *prng) 72 { 73 LTC_UNUSED_PARAM(prng); 74 return CRYPT_OK; 75 } 76 77 /** 78 Add entropy to the PRNG state 79 @param in The data to add 80 @param inlen Length of the data to add 81 @param prng PRNG state to update 82 @return CRYPT_OK if successful 83 */ 84 int sprng_add_entropy(const unsigned char *in, unsigned long inlen, prng_state *prng) 85 { 86 LTC_UNUSED_PARAM(in); 87 LTC_UNUSED_PARAM(inlen); 88 LTC_UNUSED_PARAM(prng); 89 return CRYPT_OK; 90 } 91 92 /** 93 Make the PRNG ready to read from 94 @param prng The PRNG to make active 95 @return CRYPT_OK if successful 96 */ 97 int sprng_ready(prng_state *prng) 98 { 99 LTC_UNUSED_PARAM(prng); 100 return CRYPT_OK; 101 } 102 103 /** 104 Read from the PRNG 105 @param out Destination 106 @param outlen Length of output 107 @param prng The active PRNG to read from 108 @return Number of octets read 109 */ 110 unsigned long sprng_read(unsigned char *out, unsigned long outlen, prng_state *prng) 111 { 112 LTC_ARGCHK(out != NULL); 113 LTC_UNUSED_PARAM(prng); 114 return rng_get_bytes(out, outlen, NULL); 115 } 116 117 /** 118 Terminate the PRNG 119 @param prng The PRNG to terminate 120 @return CRYPT_OK if successful 121 */ 122 int sprng_done(prng_state *prng) 123 { 124 LTC_UNUSED_PARAM(prng); 125 return CRYPT_OK; 126 } 127 128 /** 129 Export the PRNG state 130 @param out [out] Destination 131 @param outlen [in/out] Max size and resulting size of the state 132 @param prng The PRNG to export 133 @return CRYPT_OK if successful 134 */ 135 int sprng_export(unsigned char *out, unsigned long *outlen, prng_state *prng) 136 { 137 LTC_ARGCHK(outlen != NULL); 138 LTC_UNUSED_PARAM(out); 139 LTC_UNUSED_PARAM(prng); 140 141 *outlen = 0; 142 return CRYPT_OK; 143 } 144 145 /** 146 Import a PRNG state 147 @param in The PRNG state 148 @param inlen Size of the state 149 @param prng The PRNG to import 150 @return CRYPT_OK if successful 151 */ 152 int sprng_import(const unsigned char *in, unsigned long inlen, prng_state *prng) 153 { 154 LTC_UNUSED_PARAM(in); 155 LTC_UNUSED_PARAM(inlen); 156 LTC_UNUSED_PARAM(prng); 157 return CRYPT_OK; 158 } 159 160 /** 161 PRNG self-test 162 @return CRYPT_OK if successful, CRYPT_NOP if self-testing has been disabled 163 */ 164 int sprng_test(void) 165 { 166 return CRYPT_OK; 167 } 168 169 #endif 170 171 172 173 174 /* $Source: /cvs/libtom/libtomcrypt/src/prngs/sprng.c,v $ */ 175 /* $Revision: 1.6 $ */ 176 /* $Date: 2007/05/12 14:32:35 $ */ 177