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Diffstat (limited to 'include/mbedtls/nist_kw.h')
| -rw-r--r-- | include/mbedtls/nist_kw.h | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/include/mbedtls/nist_kw.h b/include/mbedtls/nist_kw.h new file mode 100644 index 0000000..d353f3d --- /dev/null +++ b/include/mbedtls/nist_kw.h @@ -0,0 +1,166 @@ +/** + * \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 <em>NIST SP 800-38F: Recommendation for + * Block Cipher Modes of Operation: Methods for Key Wrapping</em>. 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 The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ + +#ifndef MBEDTLS_NIST_KW_H +#define MBEDTLS_NIST_KW_H +#include "mbedtls/private_access.h" + +#include "mbedtls/build_info.h" + +#include "mbedtls/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 MBEDTLS_PRIVATE(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. + * <ul><li>For KW mode: a multiple of 8 bytes between 16 and 2^57-8 inclusive. </li> + * <li>For KWP mode: any length between 1 and 2^32-1 inclusive.</li></ul> + * \param[out] output The buffer holding the output data. + * <ul><li>For KW mode: Must be at least 8 bytes larger than \p in_len.</li> + * <li>For KWP mode: Must be at least 8 bytes larger rounded up to a multiple of + * 8 bytes for KWP (15 bytes at most).</li></ul> + * \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. + * <ul><li>For KW mode: a multiple of 8 bytes between 24 and 2^57 inclusive. </li> + * <li>For KWP mode: a multiple of 8 bytes between 16 and 2^32 inclusive.</li></ul> + * \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 */ |