513 lines
21 KiB
C
513 lines
21 KiB
C
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/**
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* \file ctr_drbg.h
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*
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* \brief This file contains definitions and functions for the
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* CTR_DRBG pseudorandom generator.
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*
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* CTR_DRBG is a standardized way of building a PRNG from a block-cipher
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* in counter mode operation, as defined in <em>NIST SP 800-90A:
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* Recommendation for Random Number Generation Using Deterministic Random
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* Bit Generators</em>.
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*
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* The Mbed TLS implementation of CTR_DRBG uses AES-256 (default) or AES-128
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* (if \c MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is enabled at compile time)
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* as the underlying block cipher, with a derivation function.
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* The initial seeding grabs #MBEDTLS_CTR_DRBG_ENTROPY_LEN bytes of entropy.
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* See the documentation of mbedtls_ctr_drbg_seed() for more details.
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*
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* Based on NIST SP 800-90A §10.2.1 table 3 and NIST SP 800-57 part 1 table 2,
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* here are the security strengths achieved in typical configuration:
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* - 256 bits under the default configuration of the library, with AES-256
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* and with #MBEDTLS_CTR_DRBG_ENTROPY_LEN set to 48 or more.
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* - 256 bits if AES-256 is used, #MBEDTLS_CTR_DRBG_ENTROPY_LEN is set
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* to 32 or more, and the DRBG is initialized with an explicit
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* nonce in the \c custom parameter to mbedtls_ctr_drbg_seed().
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* - 128 bits if AES-256 is used but #MBEDTLS_CTR_DRBG_ENTROPY_LEN is
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* between 24 and 47 and the DRBG is not initialized with an explicit
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* nonce (see mbedtls_ctr_drbg_seed()).
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* - 128 bits if AES-128 is used (\c MBEDTLS_CTR_DRBG_USE_128_BIT_KEY enabled)
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* and #MBEDTLS_CTR_DRBG_ENTROPY_LEN is set to 24 or more (which is
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* always the case unless it is explicitly set to a different value
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* in config.h).
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*
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* Note that the value of #MBEDTLS_CTR_DRBG_ENTROPY_LEN defaults to:
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* - \c 48 if the module \c MBEDTLS_SHA512_C is enabled and the symbol
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* \c MBEDTLS_ENTROPY_FORCE_SHA256 is disabled at compile time.
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* This is the default configuration of the library.
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* - \c 32 if the module \c MBEDTLS_SHA512_C is disabled at compile time.
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* - \c 32 if \c MBEDTLS_ENTROPY_FORCE_SHA256 is enabled at compile time.
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*/
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/*
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* Copyright (C) 2006-2019, Arm Limited (or its affiliates), All Rights Reserved
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed under the Apache License, Version 2.0 (the "License"); you may
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* not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* This file is part of Mbed TLS (https://tls.mbed.org)
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*/
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#ifndef MBEDTLS_CTR_DRBG_H
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#define MBEDTLS_CTR_DRBG_H
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#if !defined(MBEDTLS_CONFIG_FILE)
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#include "config.h"
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#else
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#include MBEDTLS_CONFIG_FILE
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#endif
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#include "aes.h"
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#if defined(MBEDTLS_THREADING_C)
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#include "threading.h"
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#endif
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#define MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED -0x0034 /**< The entropy source failed. */
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#define MBEDTLS_ERR_CTR_DRBG_REQUEST_TOO_BIG -0x0036 /**< The requested random buffer length is too big. */
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#define MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG -0x0038 /**< The input (entropy + additional data) is too large. */
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#define MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR -0x003A /**< Read or write error in file. */
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#define MBEDTLS_CTR_DRBG_BLOCKSIZE 16 /**< The block size used by the cipher. */
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#if defined(MBEDTLS_CTR_DRBG_USE_128_BIT_KEY)
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#define MBEDTLS_CTR_DRBG_KEYSIZE 16
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/**< The key size in bytes used by the cipher.
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*
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* Compile-time choice: 16 bytes (128 bits)
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* because #MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is enabled.
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*/
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#else
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#define MBEDTLS_CTR_DRBG_KEYSIZE 32
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/**< The key size in bytes used by the cipher.
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*
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* Compile-time choice: 32 bytes (256 bits)
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* because \c MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is disabled.
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*/
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#endif
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#define MBEDTLS_CTR_DRBG_KEYBITS ( MBEDTLS_CTR_DRBG_KEYSIZE * 8 ) /**< The key size for the DRBG operation, in bits. */
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#define MBEDTLS_CTR_DRBG_SEEDLEN ( MBEDTLS_CTR_DRBG_KEYSIZE + MBEDTLS_CTR_DRBG_BLOCKSIZE ) /**< The seed length, calculated as (counter + AES key). */
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/**
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* \name SECTION: Module settings
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*
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* The configuration options you can set for this module are in this section.
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* Either change them in config.h or define them using the compiler command
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* line.
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* \{
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*/
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/** \def MBEDTLS_CTR_DRBG_ENTROPY_LEN
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*
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* \brief The amount of entropy used per seed by default, in bytes.
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*/
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#if !defined(MBEDTLS_CTR_DRBG_ENTROPY_LEN)
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#if defined(MBEDTLS_SHA512_C) && !defined(MBEDTLS_ENTROPY_FORCE_SHA256)
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/** This is 48 bytes because the entropy module uses SHA-512
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* (\c MBEDTLS_ENTROPY_FORCE_SHA256 is disabled).
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*/
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#define MBEDTLS_CTR_DRBG_ENTROPY_LEN 48
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#else /* defined(MBEDTLS_SHA512_C) && !defined(MBEDTLS_ENTROPY_FORCE_SHA256) */
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/** This is 32 bytes because the entropy module uses SHA-256
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* (the SHA512 module is disabled or
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* \c MBEDTLS_ENTROPY_FORCE_SHA256 is enabled).
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*/
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#if !defined(MBEDTLS_CTR_DRBG_USE_128_BIT_KEY)
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/** \warning To achieve a 256-bit security strength, you must pass a nonce
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* to mbedtls_ctr_drbg_seed().
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*/
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#endif /* !defined(MBEDTLS_CTR_DRBG_USE_128_BIT_KEY) */
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#define MBEDTLS_CTR_DRBG_ENTROPY_LEN 32
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#endif /* defined(MBEDTLS_SHA512_C) && !defined(MBEDTLS_ENTROPY_FORCE_SHA256) */
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#endif /* !defined(MBEDTLS_CTR_DRBG_ENTROPY_LEN) */
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#if !defined(MBEDTLS_CTR_DRBG_RESEED_INTERVAL)
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#define MBEDTLS_CTR_DRBG_RESEED_INTERVAL 10000
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/**< The interval before reseed is performed by default. */
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#endif
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#if !defined(MBEDTLS_CTR_DRBG_MAX_INPUT)
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#define MBEDTLS_CTR_DRBG_MAX_INPUT 256
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/**< The maximum number of additional input Bytes. */
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#endif
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#if !defined(MBEDTLS_CTR_DRBG_MAX_REQUEST)
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#define MBEDTLS_CTR_DRBG_MAX_REQUEST 1024
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/**< The maximum number of requested Bytes per call. */
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#endif
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#if !defined(MBEDTLS_CTR_DRBG_MAX_SEED_INPUT)
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#define MBEDTLS_CTR_DRBG_MAX_SEED_INPUT 384
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/**< The maximum size of seed or reseed buffer in bytes. */
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#endif
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/* \} name SECTION: Module settings */
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#define MBEDTLS_CTR_DRBG_PR_OFF 0
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/**< Prediction resistance is disabled. */
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#define MBEDTLS_CTR_DRBG_PR_ON 1
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/**< Prediction resistance is enabled. */
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* \brief The CTR_DRBG context structure.
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*/
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typedef struct mbedtls_ctr_drbg_context
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{
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unsigned char counter[16]; /*!< The counter (V). */
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int reseed_counter; /*!< The reseed counter. */
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int prediction_resistance; /*!< This determines whether prediction
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resistance is enabled, that is
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whether to systematically reseed before
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each random generation. */
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size_t entropy_len; /*!< The amount of entropy grabbed on each
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seed or reseed operation. */
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int reseed_interval; /*!< The reseed interval. */
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mbedtls_aes_context aes_ctx; /*!< The AES context. */
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/*
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* Callbacks (Entropy)
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*/
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int (*f_entropy)(void *, unsigned char *, size_t);
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/*!< The entropy callback function. */
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void *p_entropy; /*!< The context for the entropy function. */
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#if defined(MBEDTLS_THREADING_C)
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mbedtls_threading_mutex_t mutex;
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#endif
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}
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mbedtls_ctr_drbg_context;
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/**
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* \brief This function initializes the CTR_DRBG context,
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* and prepares it for mbedtls_ctr_drbg_seed()
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* or mbedtls_ctr_drbg_free().
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*
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* \param ctx The CTR_DRBG context to initialize.
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*/
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void mbedtls_ctr_drbg_init( mbedtls_ctr_drbg_context *ctx );
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/**
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* \brief This function seeds and sets up the CTR_DRBG
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* entropy source for future reseeds.
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*
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* A typical choice for the \p f_entropy and \p p_entropy parameters is
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* to use the entropy module:
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* - \p f_entropy is mbedtls_entropy_func();
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* - \p p_entropy is an instance of ::mbedtls_entropy_context initialized
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* with mbedtls_entropy_init() (which registers the platform's default
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* entropy sources).
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*
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* The entropy length is #MBEDTLS_CTR_DRBG_ENTROPY_LEN by default.
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* You can override it by calling mbedtls_ctr_drbg_set_entropy_len().
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*
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* You can provide a personalization string in addition to the
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* entropy source, to make this instantiation as unique as possible.
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*
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* \note The _seed_material_ value passed to the derivation
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* function in the CTR_DRBG Instantiate Process
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* described in NIST SP 800-90A §10.2.1.3.2
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* is the concatenation of the string obtained from
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* calling \p f_entropy and the \p custom string.
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* The origin of the nonce depends on the value of
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* the entropy length relative to the security strength.
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* - If the entropy length is at least 1.5 times the
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* security strength then the nonce is taken from the
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* string obtained with \p f_entropy.
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* - If the entropy length is less than the security
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* strength, then the nonce is taken from \p custom.
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* In this case, for compliance with SP 800-90A,
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* you must pass a unique value of \p custom at
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* each invocation. See SP 800-90A §8.6.7 for more
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* details.
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*/
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#if MBEDTLS_CTR_DRBG_ENTROPY_LEN < MBEDTLS_CTR_DRBG_KEYSIZE * 3 / 2
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/** \warning When #MBEDTLS_CTR_DRBG_ENTROPY_LEN is less than
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* #MBEDTLS_CTR_DRBG_KEYSIZE * 3 / 2, to achieve the
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* maximum security strength permitted by CTR_DRBG,
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* you must pass a value of \p custom that is a nonce:
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* this value must never be repeated in subsequent
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* runs of the same application or on a different
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* device.
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*/
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#endif
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/**
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* \param ctx The CTR_DRBG context to seed.
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* It must have been initialized with
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* mbedtls_ctr_drbg_init().
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* After a successful call to mbedtls_ctr_drbg_seed(),
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* you may not call mbedtls_ctr_drbg_seed() again on
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* the same context unless you call
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* mbedtls_ctr_drbg_free() and mbedtls_ctr_drbg_init()
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* again first.
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* \param f_entropy The entropy callback, taking as arguments the
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* \p p_entropy context, the buffer to fill, and the
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* length of the buffer.
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* \p f_entropy is always called with a buffer size
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* equal to the entropy length.
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* \param p_entropy The entropy context to pass to \p f_entropy.
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* \param custom The personalization string.
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* This can be \c NULL, in which case the personalization
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* string is empty regardless of the value of \p len.
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* \param len The length of the personalization string.
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* This must be at most
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* #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT
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* - #MBEDTLS_CTR_DRBG_ENTROPY_LEN.
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED on failure.
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*/
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int mbedtls_ctr_drbg_seed( mbedtls_ctr_drbg_context *ctx,
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int (*f_entropy)(void *, unsigned char *, size_t),
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void *p_entropy,
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const unsigned char *custom,
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size_t len );
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/**
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* \brief This function clears CTR_CRBG context data.
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*
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* \param ctx The CTR_DRBG context to clear.
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*/
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void mbedtls_ctr_drbg_free( mbedtls_ctr_drbg_context *ctx );
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/**
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* \brief This function turns prediction resistance on or off.
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* The default value is off.
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*
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* \note If enabled, entropy is gathered at the beginning of
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* every call to mbedtls_ctr_drbg_random_with_add()
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* or mbedtls_ctr_drbg_random().
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* Only use this if your entropy source has sufficient
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* throughput.
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*
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* \param ctx The CTR_DRBG context.
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* \param resistance #MBEDTLS_CTR_DRBG_PR_ON or #MBEDTLS_CTR_DRBG_PR_OFF.
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*/
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void mbedtls_ctr_drbg_set_prediction_resistance( mbedtls_ctr_drbg_context *ctx,
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int resistance );
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/**
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* \brief This function sets the amount of entropy grabbed on each
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* seed or reseed.
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*
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* The default value is #MBEDTLS_CTR_DRBG_ENTROPY_LEN.
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*
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* \note The security strength of CTR_DRBG is bounded by the
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* entropy length. Thus:
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* - When using AES-256
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* (\c MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is disabled,
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* which is the default),
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* \p len must be at least 32 (in bytes)
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* to achieve a 256-bit strength.
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* - When using AES-128
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* (\c MBEDTLS_CTR_DRBG_USE_128_BIT_KEY is enabled)
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* \p len must be at least 16 (in bytes)
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* to achieve a 128-bit strength.
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*
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* \param ctx The CTR_DRBG context.
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* \param len The amount of entropy to grab, in bytes.
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* This must be at most #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT.
|
||
|
|
*/
|
||
|
|
void mbedtls_ctr_drbg_set_entropy_len( mbedtls_ctr_drbg_context *ctx,
|
||
|
|
size_t len );
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief This function sets the reseed interval.
|
||
|
|
*
|
||
|
|
* The reseed interval is the number of calls to mbedtls_ctr_drbg_random()
|
||
|
|
* or mbedtls_ctr_drbg_random_with_add() after which the entropy function
|
||
|
|
* is called again.
|
||
|
|
*
|
||
|
|
* The default value is #MBEDTLS_CTR_DRBG_RESEED_INTERVAL.
|
||
|
|
*
|
||
|
|
* \param ctx The CTR_DRBG context.
|
||
|
|
* \param interval The reseed interval.
|
||
|
|
*/
|
||
|
|
void mbedtls_ctr_drbg_set_reseed_interval( mbedtls_ctr_drbg_context *ctx,
|
||
|
|
int interval );
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief This function reseeds the CTR_DRBG context, that is
|
||
|
|
* extracts data from the entropy source.
|
||
|
|
*
|
||
|
|
* \param ctx The CTR_DRBG context.
|
||
|
|
* \param additional Additional data to add to the state. Can be \c NULL.
|
||
|
|
* \param len The length of the additional data.
|
||
|
|
* This must be less than
|
||
|
|
* #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT - \c entropy_len
|
||
|
|
* where \c entropy_len is the entropy length
|
||
|
|
* configured for the context.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED on failure.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_reseed( mbedtls_ctr_drbg_context *ctx,
|
||
|
|
const unsigned char *additional, size_t len );
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief This function updates the state of the CTR_DRBG context.
|
||
|
|
*
|
||
|
|
* \param ctx The CTR_DRBG context.
|
||
|
|
* \param additional The data to update the state with. This must not be
|
||
|
|
* \c NULL unless \p add_len is \c 0.
|
||
|
|
* \param add_len Length of \p additional in bytes. This must be at
|
||
|
|
* most #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG if
|
||
|
|
* \p add_len is more than
|
||
|
|
* #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT.
|
||
|
|
* \return An error from the underlying AES cipher on failure.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_update_ret( mbedtls_ctr_drbg_context *ctx,
|
||
|
|
const unsigned char *additional,
|
||
|
|
size_t add_len );
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief This function updates a CTR_DRBG instance with additional
|
||
|
|
* data and uses it to generate random data.
|
||
|
|
*
|
||
|
|
* This function automatically reseeds if the reseed counter is exceeded
|
||
|
|
* or prediction resistance is enabled.
|
||
|
|
*
|
||
|
|
* \param p_rng The CTR_DRBG context. This must be a pointer to a
|
||
|
|
* #mbedtls_ctr_drbg_context structure.
|
||
|
|
* \param output The buffer to fill.
|
||
|
|
* \param output_len The length of the buffer in bytes.
|
||
|
|
* \param additional Additional data to update. Can be \c NULL, in which
|
||
|
|
* case the additional data is empty regardless of
|
||
|
|
* the value of \p add_len.
|
||
|
|
* \param add_len The length of the additional data
|
||
|
|
* if \p additional is not \c NULL.
|
||
|
|
* This must be less than #MBEDTLS_CTR_DRBG_MAX_INPUT
|
||
|
|
* and less than
|
||
|
|
* #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT - \c entropy_len
|
||
|
|
* where \c entropy_len is the entropy length
|
||
|
|
* configured for the context.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED or
|
||
|
|
* #MBEDTLS_ERR_CTR_DRBG_REQUEST_TOO_BIG on failure.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_random_with_add( void *p_rng,
|
||
|
|
unsigned char *output, size_t output_len,
|
||
|
|
const unsigned char *additional, size_t add_len );
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief This function uses CTR_DRBG to generate random data.
|
||
|
|
*
|
||
|
|
* This function automatically reseeds if the reseed counter is exceeded
|
||
|
|
* or prediction resistance is enabled.
|
||
|
|
*
|
||
|
|
*
|
||
|
|
* \param p_rng The CTR_DRBG context. This must be a pointer to a
|
||
|
|
* #mbedtls_ctr_drbg_context structure.
|
||
|
|
* \param output The buffer to fill.
|
||
|
|
* \param output_len The length of the buffer in bytes.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED or
|
||
|
|
* #MBEDTLS_ERR_CTR_DRBG_REQUEST_TOO_BIG on failure.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_random( void *p_rng,
|
||
|
|
unsigned char *output, size_t output_len );
|
||
|
|
|
||
|
|
|
||
|
|
#if ! defined(MBEDTLS_DEPRECATED_REMOVED)
|
||
|
|
#if defined(MBEDTLS_DEPRECATED_WARNING)
|
||
|
|
#define MBEDTLS_DEPRECATED __attribute__((deprecated))
|
||
|
|
#else
|
||
|
|
#define MBEDTLS_DEPRECATED
|
||
|
|
#endif
|
||
|
|
/**
|
||
|
|
* \brief This function updates the state of the CTR_DRBG context.
|
||
|
|
*
|
||
|
|
* \deprecated Superseded by mbedtls_ctr_drbg_update_ret()
|
||
|
|
* in 2.16.0.
|
||
|
|
*
|
||
|
|
* \note If \p add_len is greater than
|
||
|
|
* #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT, only the first
|
||
|
|
* #MBEDTLS_CTR_DRBG_MAX_SEED_INPUT Bytes are used.
|
||
|
|
* The remaining Bytes are silently discarded.
|
||
|
|
*
|
||
|
|
* \param ctx The CTR_DRBG context.
|
||
|
|
* \param additional The data to update the state with.
|
||
|
|
* \param add_len Length of \p additional data.
|
||
|
|
*/
|
||
|
|
MBEDTLS_DEPRECATED void mbedtls_ctr_drbg_update(
|
||
|
|
mbedtls_ctr_drbg_context *ctx,
|
||
|
|
const unsigned char *additional,
|
||
|
|
size_t add_len );
|
||
|
|
#undef MBEDTLS_DEPRECATED
|
||
|
|
#endif /* !MBEDTLS_DEPRECATED_REMOVED */
|
||
|
|
|
||
|
|
#if defined(MBEDTLS_FS_IO)
|
||
|
|
/**
|
||
|
|
* \brief This function writes a seed file.
|
||
|
|
*
|
||
|
|
* \param ctx The CTR_DRBG context.
|
||
|
|
* \param path The name of the file.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR on file error.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED on reseed
|
||
|
|
* failure.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_write_seed_file( mbedtls_ctr_drbg_context *ctx, const char *path );
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief This function reads and updates a seed file. The seed
|
||
|
|
* is added to this instance.
|
||
|
|
*
|
||
|
|
* \param ctx The CTR_DRBG context.
|
||
|
|
* \param path The name of the file.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR on file error.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_ENTROPY_SOURCE_FAILED on
|
||
|
|
* reseed failure.
|
||
|
|
* \return #MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG if the existing
|
||
|
|
* seed file is too large.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_update_seed_file( mbedtls_ctr_drbg_context *ctx, const char *path );
|
||
|
|
#endif /* MBEDTLS_FS_IO */
|
||
|
|
|
||
|
|
#if defined(MBEDTLS_SELF_TEST)
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \brief The CTR_DRBG checkup routine.
|
||
|
|
*
|
||
|
|
* \return \c 0 on success.
|
||
|
|
* \return \c 1 on failure.
|
||
|
|
*/
|
||
|
|
int mbedtls_ctr_drbg_self_test( int verbose );
|
||
|
|
|
||
|
|
#endif /* MBEDTLS_SELF_TEST */
|
||
|
|
|
||
|
|
/* Internal functions (do not call directly) */
|
||
|
|
int mbedtls_ctr_drbg_seed_entropy_len( mbedtls_ctr_drbg_context *,
|
||
|
|
int (*)(void *, unsigned char *, size_t), void *,
|
||
|
|
const unsigned char *, size_t, size_t );
|
||
|
|
|
||
|
|
#ifdef __cplusplus
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif /* ctr_drbg.h */
|