diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h index 4689f3a4d..9e6bb8a46 100644 --- a/include/mbedtls/check_config.h +++ b/include/mbedtls/check_config.h @@ -87,6 +87,11 @@ #error "MBEDTLS_CMAC_C defined, but not all prerequisites" #endif +#if defined(MBEDTLS_NIST_KW_C) && \ + ( !defined(MBEDTLS_AES_C) || !defined(MBEDTLS_CIPHER_C) ) +#error "MBEDTLS_NIST_KW_C defined, but not all prerequisites" +#endif + #if defined(MBEDTLS_ECDH_C) && !defined(MBEDTLS_ECP_C) #error "MBEDTLS_ECDH_C defined, but not all prerequisites" #endif diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h index 17208b589..70820be56 100644 --- a/include/mbedtls/config.h +++ b/include/mbedtls/config.h @@ -308,6 +308,7 @@ //#define MBEDTLS_DHM_ALT //#define MBEDTLS_ECJPAKE_ALT //#define MBEDTLS_GCM_ALT +//#define MBEDTLS_NIST_KW_ALT //#define MBEDTLS_MD2_ALT //#define MBEDTLS_MD4_ALT //#define MBEDTLS_MD5_ALT @@ -2248,6 +2249,19 @@ */ #define MBEDTLS_HMAC_DRBG_C +/** + * \def MBEDTLS_NIST_KW_C + * + * Enable the Key Wrapping mode for 128-bit block ciphers, + * as defined in NIST SP 800-38F. Only KW and KWP modes + * are supported. At the moment, only AES is approved by NIST. + * + * Module: library/nist_kw.c + * + * Requires: MBEDTLS_AES_C and MBEDTLS_CIPHER_C + */ +//#define MBEDTLS_NIST_KW_C + /** * \def MBEDTLS_MD_C * diff --git a/include/mbedtls/nist_kw.h b/include/mbedtls/nist_kw.h new file mode 100644 index 000000000..5a0f656a8 --- /dev/null +++ b/include/mbedtls/nist_kw.h @@ -0,0 +1,178 @@ +/** + * \file nist_kw.h + * + * \brief This file provides an API for key wrapping (KW) and key wrapping with + * padding (KWP) as defined in NIST SP 800-38F. + * https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-38F.pdf + * + * Key wrapping specifies a deterministic authenticated-encryption mode + * of operation, according to NIST SP 800-38F: Recommendation for + * Block Cipher Modes of Operation: Methods for Key Wrapping. Its + * purpose is to protect cryptographic keys. + * + * Its equivalent is RFC 3394 for KW, and RFC 5649 for KWP. + * https://tools.ietf.org/html/rfc3394 + * https://tools.ietf.org/html/rfc5649 + * + */ +/* + * Copyright (C) 2018, Arm Limited (or its affiliates), All Rights Reserved + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + * This file is part of Mbed TLS (https://tls.mbed.org) + */ + +#ifndef MBEDTLS_NIST_KW_H +#define MBEDTLS_NIST_KW_H + +#include "cipher.h" + +#ifdef __cplusplus +extern "C" { +#endif + +typedef enum +{ + MBEDTLS_KW_MODE_KW = 0, + MBEDTLS_KW_MODE_KWP = 1 +} mbedtls_nist_kw_mode_t; + +#if !defined(MBEDTLS_NIST_KW_ALT) +// Regular implementation +// + +/** + * \brief The key wrapping context-type definition. The key wrapping context is passed + * to the APIs called. + * + * \note The definition of this type may change in future library versions. + * Don't make any assumptions on this context! + */ +typedef struct { + mbedtls_cipher_context_t cipher_ctx; /*!< The cipher context used. */ +} mbedtls_nist_kw_context; + +#else /* MBEDTLS_NIST_key wrapping_ALT */ +#include "nist_kw_alt.h" +#endif /* MBEDTLS_NIST_KW_ALT */ + +/** + * \brief This function initializes the specified key wrapping context + * to make references valid and prepare the context + * for mbedtls_nist_kw_setkey() or mbedtls_nist_kw_free(). + * + * \param ctx The key wrapping context to initialize. + * + */ +void mbedtls_nist_kw_init( mbedtls_nist_kw_context *ctx ); + +/** + * \brief This function initializes the key wrapping context set in the + * \p ctx parameter and sets the encryption key. + * + * \param ctx The key wrapping context. + * \param cipher The 128-bit block cipher to use. Only AES is supported. + * \param key The Key Encryption Key (KEK). + * \param keybits The KEK size in bits. This must be acceptable by the cipher. + * \param is_wrap Specify whether the operation within the context is wrapping or unwrapping + * + * \return \c 0 on success. + * \return \c MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA for any invalid input. + * \return \c MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE for 128-bit block ciphers + * which are not supported. + * \return cipher-specific error code on failure of the underlying cipher. + */ +int mbedtls_nist_kw_setkey( mbedtls_nist_kw_context *ctx, + mbedtls_cipher_id_t cipher, + const unsigned char *key, + unsigned int keybits, + const int is_wrap ); + +/** + * \brief This function releases and clears the specified key wrapping context + * and underlying cipher sub-context. + * + * \param ctx The key wrapping context to clear. + */ +void mbedtls_nist_kw_free( mbedtls_nist_kw_context *ctx ); + +/** + * \brief This function encrypts a buffer using key wrapping. + * + * \param ctx The key wrapping context to use for encryption. + * \param mode The key wrapping mode to use (MBEDTLS_KW_MODE_KW or MBEDTLS_KW_MODE_KWP) + * \param input The buffer holding the input data. + * \param in_len The length of the input data in Bytes. + * The input uses units of 8 Bytes called semiblocks. + * + * \param[out] output The buffer holding the output data. + * + * \param[out] out_len The number of bytes written to the output buffer. \c 0 on failure. + * \param[in] out_size The capacity of the output buffer. + * + * \return \c 0 on success. + * \return \c MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA for invalid input length. + * \return cipher-specific error code on failure of the underlying cipher. + */ +int mbedtls_nist_kw_wrap( mbedtls_nist_kw_context *ctx, mbedtls_nist_kw_mode_t mode, + const unsigned char *input, size_t in_len, + unsigned char *output, size_t* out_len, size_t out_size ); + +/** + * \brief This function decrypts a buffer using key wrapping. + * + * \param ctx The key wrapping context to use for decryption. + * \param mode The key wrapping mode to use (MBEDTLS_KW_MODE_KW or MBEDTLS_KW_MODE_KWP) + * \param input The buffer holding the input data. + * \param in_len The length of the input data in Bytes. + * The input uses units of 8 Bytes called semiblocks. + * The input must be a multiple of semiblocks. + * + * \param[out] output The buffer holding the output data. + * The output buffer's minimal length is 8 bytes shorter than \p in_len. + * \param[out] out_len The number of bytes written to the output buffer. \c 0 on failure. + * For KWP mode, the length could be up to 15 bytes shorter than \p in_len, + * depending on how much padding was added to the data. + * \param[in] out_size The capacity of the output buffer. + * + * \return \c 0 on success. + * \return \c MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA for invalid input length. + * \return \c MBEDTLS_ERR_CIPHER_AUTH_FAILED for verification failure of the ciphertext. + * \return cipher-specific error code on failure of the underlying cipher. + */ +int mbedtls_nist_kw_unwrap( mbedtls_nist_kw_context *ctx, mbedtls_nist_kw_mode_t mode, + const unsigned char *input, size_t in_len, + unsigned char *output, size_t* out_len, size_t out_size); + + +#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C) +/** + * \brief The key wrapping checkup routine. + * + * \return \c 0 on success. + * \return \c 1 on failure. + */ +int mbedtls_nist_kw_self_test( int verbose ); +#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */ + +#ifdef __cplusplus +} +#endif + +#endif /* MBEDTLS_NIST_KW_H */ diff --git a/library/version_features.c b/library/version_features.c index b6135462f..777b6034c 100644 --- a/library/version_features.c +++ b/library/version_features.c @@ -126,6 +126,9 @@ static const char *features[] = { #if defined(MBEDTLS_GCM_ALT) "MBEDTLS_GCM_ALT", #endif /* MBEDTLS_GCM_ALT */ +#if defined(MBEDTLS_NIST_KW_ALT) + "MBEDTLS_NIST_KW_ALT", +#endif /* MBEDTLS_NIST_KW_ALT */ #if defined(MBEDTLS_MD2_ALT) "MBEDTLS_MD2_ALT", #endif /* MBEDTLS_MD2_ALT */ @@ -618,6 +621,9 @@ static const char *features[] = { #if defined(MBEDTLS_HMAC_DRBG_C) "MBEDTLS_HMAC_DRBG_C", #endif /* MBEDTLS_HMAC_DRBG_C */ +#if defined(MBEDTLS_NIST_KW_C) + "MBEDTLS_NIST_KW_C", +#endif /* MBEDTLS_NIST_KW_C */ #if defined(MBEDTLS_MD_C) "MBEDTLS_MD_C", #endif /* MBEDTLS_MD_C */