md.h

00001 /**
00002  * \file mbedtls_md.h
00003  *
00004  * \brief Generic message digest wrapper
00005  *
00006  * \author Adriaan de Jong <dejong@fox-it.com>
00007  *
00008  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00009  *  SPDX-License-Identifier: Apache-2.0
00010  *
00011  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00012  *  not use this file except in compliance with the License.
00013  *  You may obtain a copy of the License at
00014  *
00015  *  http://www.apache.org/licenses/LICENSE-2.0
00016  *
00017  *  Unless required by applicable law or agreed to in writing, software
00018  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00019  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00020  *  See the License for the specific language governing permissions and
00021  *  limitations under the License.
00022  *
00023  *  This file is part of mbed TLS (https://tls.mbed.org)
00024  */
00025 #ifndef MBEDTLS_MD_H
00026 #define MBEDTLS_MD_H
00027 
00028 #include <stddef.h>
00029 
00030 #define MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE                -0x5080  /**< The selected feature is not available. */
00031 #define MBEDTLS_ERR_MD_BAD_INPUT_DATA                     -0x5100  /**< Bad input parameters to function. */
00032 #define MBEDTLS_ERR_MD_ALLOC_FAILED                       -0x5180  /**< Failed to allocate memory. */
00033 #define MBEDTLS_ERR_MD_FILE_IO_ERROR                      -0x5200  /**< Opening or reading of file failed. */
00034 
00035 #ifdef __cplusplus
00036 extern "C" {
00037 #endif
00038 
00039 typedef enum {
00040     MBEDTLS_MD_NONE=0,
00041     MBEDTLS_MD_MD2,
00042     MBEDTLS_MD_MD4,
00043     MBEDTLS_MD_MD5,
00044     MBEDTLS_MD_SHA1,
00045     MBEDTLS_MD_SHA224,
00046     MBEDTLS_MD_SHA256,
00047     MBEDTLS_MD_SHA384,
00048     MBEDTLS_MD_SHA512,
00049     MBEDTLS_MD_RIPEMD160,
00050 } mbedtls_md_type_t;
00051 
00052 #if defined(MBEDTLS_SHA512_C)
00053 #define MBEDTLS_MD_MAX_SIZE         64  /* longest known is SHA512 */
00054 #else
00055 #define MBEDTLS_MD_MAX_SIZE         32  /* longest known is SHA256 or less */
00056 #endif
00057 
00058 /**
00059  * Opaque struct defined in md_internal.h
00060  */
00061 typedef struct mbedtls_md_info_t mbedtls_md_info_t;
00062 
00063 /**
00064  * Generic message digest context.
00065  */
00066 typedef struct {
00067     /** Information about the associated message digest */
00068     const mbedtls_md_info_t *md_info;
00069 
00070     /** Digest-specific context */
00071     void *md_ctx;
00072 
00073     /** HMAC part of the context */
00074     void *hmac_ctx;
00075 } mbedtls_md_context_t;
00076 
00077 /**
00078  * \brief Returns the list of digests supported by the generic digest module.
00079  *
00080  * \return          a statically allocated array of digests, the last entry
00081  *                  is 0.
00082  */
00083 const int *mbedtls_md_list( void );
00084 
00085 /**
00086  * \brief           Returns the message digest information associated with the
00087  *                  given digest name.
00088  *
00089  * \param md_name   Name of the digest to search for.
00090  *
00091  * \return          The message digest information associated with md_name or
00092  *                  NULL if not found.
00093  */
00094 const mbedtls_md_info_t *mbedtls_md_info_from_string( const char *md_name );
00095 
00096 /**
00097  * \brief           Returns the message digest information associated with the
00098  *                  given digest type.
00099  *
00100  * \param md_type   type of digest to search for.
00101  *
00102  * \return          The message digest information associated with md_type or
00103  *                  NULL if not found.
00104  */
00105 const mbedtls_md_info_t *mbedtls_md_info_from_type( mbedtls_md_type_t md_type );
00106 
00107 /**
00108  * \brief           Initialize a md_context (as NONE)
00109  *                  This should always be called first.
00110  *                  Prepares the context for mbedtls_md_setup() or mbedtls_md_free().
00111  */
00112 void mbedtls_md_init( mbedtls_md_context_t *ctx );
00113 
00114 /**
00115  * \brief           Free and clear the internal structures of ctx.
00116  *                  Can be called at any time after mbedtls_md_init().
00117  *                  Mandatory once mbedtls_md_setup() has been called.
00118  */
00119 void mbedtls_md_free( mbedtls_md_context_t *ctx );
00120 
00121 #if ! defined(MBEDTLS_DEPRECATED_REMOVED)
00122 #if defined(MBEDTLS_DEPRECATED_WARNING)
00123 #define MBEDTLS_DEPRECATED    __attribute__((deprecated))
00124 #else
00125 #define MBEDTLS_DEPRECATED
00126 #endif
00127 /**
00128  * \brief           Select MD to use and allocate internal structures.
00129  *                  Should be called after mbedtls_md_init() or mbedtls_md_free().
00130  *                  Makes it necessary to call mbedtls_md_free() later.
00131  *
00132  * \deprecated      Superseded by mbedtls_md_setup() in 2.0.0
00133  *
00134  * \param ctx       Context to set up.
00135  * \param md_info   Message digest to use.
00136  *
00137  * \returns         \c 0 on success,
00138  *                  \c MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter failure,
00139  *                  \c MBEDTLS_ERR_MD_ALLOC_FAILED memory allocation failure.
00140  */
00141 int mbedtls_md_init_ctx( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info ) MBEDTLS_DEPRECATED;
00142 #undef MBEDTLS_DEPRECATED
00143 #endif /* MBEDTLS_DEPRECATED_REMOVED */
00144 
00145 /**
00146  * \brief           Select MD to use and allocate internal structures.
00147  *                  Should be called after mbedtls_md_init() or mbedtls_md_free().
00148  *                  Makes it necessary to call mbedtls_md_free() later.
00149  *
00150  * \param ctx       Context to set up.
00151  * \param md_info   Message digest to use.
00152  * \param hmac      0 to save some memory if HMAC will not be used,
00153  *                  non-zero is HMAC is going to be used with this context.
00154  *
00155  * \returns         \c 0 on success,
00156  *                  \c MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter failure,
00157  *                  \c MBEDTLS_ERR_MD_ALLOC_FAILED memory allocation failure.
00158  */
00159 int mbedtls_md_setup( mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac );
00160 
00161 /**
00162  * \brief           Clone the state of an MD context
00163  *
00164  * \note            The two contexts must have been setup to the same type
00165  *                  (cloning from SHA-256 to SHA-512 make no sense).
00166  *
00167  * \warning         Only clones the MD state, not the HMAC state! (for now)
00168  *
00169  * \param dst       The destination context
00170  * \param src       The context to be cloned
00171  *
00172  * \return          \c 0 on success,
00173  *                  \c MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter failure.
00174  */
00175 int mbedtls_md_clone( mbedtls_md_context_t *dst,
00176                       const mbedtls_md_context_t *src );
00177 
00178 /**
00179  * \brief           Returns the size of the message digest output.
00180  *
00181  * \param md_info   message digest info
00182  *
00183  * \return          size of the message digest output in bytes.
00184  */
00185 unsigned char mbedtls_md_get_size( const mbedtls_md_info_t *md_info );
00186 
00187 /**
00188  * \brief           Returns the type of the message digest output.
00189  *
00190  * \param md_info   message digest info
00191  *
00192  * \return          type of the message digest output.
00193  */
00194 mbedtls_md_type_t mbedtls_md_get_type( const mbedtls_md_info_t *md_info );
00195 
00196 /**
00197  * \brief           Returns the name of the message digest output.
00198  *
00199  * \param md_info   message digest info
00200  *
00201  * \return          name of the message digest output.
00202  */
00203 const char *mbedtls_md_get_name( const mbedtls_md_info_t *md_info );
00204 
00205 /**
00206  * \brief           Prepare the context to digest a new message.
00207  *                  Generally called after mbedtls_md_setup() or mbedtls_md_finish().
00208  *                  Followed by mbedtls_md_update().
00209  *
00210  * \param ctx       generic message digest context.
00211  *
00212  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00213  *                  verification fails.
00214  */
00215 int mbedtls_md_starts( mbedtls_md_context_t *ctx );
00216 
00217 /**
00218  * \brief           Generic message digest process buffer
00219  *                  Called between mbedtls_md_starts() and mbedtls_md_finish().
00220  *                  May be called repeatedly.
00221  *
00222  * \param ctx       Generic message digest context
00223  * \param input     buffer holding the  datal
00224  * \param ilen      length of the input data
00225  *
00226  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00227  *                  verification fails.
00228  */
00229 int mbedtls_md_update( mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen );
00230 
00231 /**
00232  * \brief           Generic message digest final digest
00233  *                  Called after mbedtls_md_update().
00234  *                  Usually followed by mbedtls_md_free() or mbedtls_md_starts().
00235  *
00236  * \param ctx       Generic message digest context
00237  * \param output    Generic message digest checksum result
00238  *
00239  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00240  *                  verification fails.
00241  */
00242 int mbedtls_md_finish( mbedtls_md_context_t *ctx, unsigned char *output );
00243 
00244 /**
00245  * \brief          Output = message_digest( input buffer )
00246  *
00247  * \param md_info  message digest info
00248  * \param input    buffer holding the  data
00249  * \param ilen     length of the input data
00250  * \param output   Generic message digest checksum result
00251  *
00252  * \returns        0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00253  *                 verification fails.
00254  */
00255 int mbedtls_md( const mbedtls_md_info_t *md_info, const unsigned char *input, size_t ilen,
00256         unsigned char *output );
00257 
00258 #if defined(MBEDTLS_FS_IO)
00259 /**
00260  * \brief          Output = message_digest( file contents )
00261  *
00262  * \param md_info  message digest info
00263  * \param path     input file name
00264  * \param output   generic message digest checksum result
00265  *
00266  * \return         0 if successful,
00267  *                 MBEDTLS_ERR_MD_FILE_IO_ERROR if file input failed,
00268  *                 MBEDTLS_ERR_MD_BAD_INPUT_DATA if md_info was NULL.
00269  */
00270 int mbedtls_md_file( const mbedtls_md_info_t *md_info, const char *path,
00271                      unsigned char *output );
00272 #endif /* MBEDTLS_FS_IO */
00273 
00274 /**
00275  * \brief           Set HMAC key and prepare to authenticate a new message.
00276  *                  Usually called after mbedtls_md_setup() or mbedtls_md_hmac_finish().
00277  *
00278  * \param ctx       HMAC context
00279  * \param key       HMAC secret key
00280  * \param keylen    length of the HMAC key in bytes
00281  *
00282  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00283  *                  verification fails.
00284  */
00285 int mbedtls_md_hmac_starts( mbedtls_md_context_t *ctx, const unsigned char *key,
00286                     size_t keylen );
00287 
00288 /**
00289  * \brief           Generic HMAC process buffer.
00290  *                  Called between mbedtls_md_hmac_starts() or mbedtls_md_hmac_reset()
00291  *                  and mbedtls_md_hmac_finish().
00292  *                  May be called repeatedly.
00293  *
00294  * \param ctx       HMAC context
00295  * \param input     buffer holding the  data
00296  * \param ilen      length of the input data
00297  *
00298  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00299  *                  verification fails.
00300  */
00301 int mbedtls_md_hmac_update( mbedtls_md_context_t *ctx, const unsigned char *input,
00302                     size_t ilen );
00303 
00304 /**
00305  * \brief           Output HMAC.
00306  *                  Called after mbedtls_md_hmac_update().
00307  *                  Usually followed my mbedtls_md_hmac_reset(), mbedtls_md_hmac_starts(),
00308  *                  or mbedtls_md_free().
00309  *
00310  * \param ctx       HMAC context
00311  * \param output    Generic HMAC checksum result
00312  *
00313  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00314  *                  verification fails.
00315  */
00316 int mbedtls_md_hmac_finish( mbedtls_md_context_t *ctx, unsigned char *output);
00317 
00318 /**
00319  * \brief           Prepare to authenticate a new message with the same key.
00320  *                  Called after mbedtls_md_hmac_finish() and before mbedtls_md_hmac_update().
00321  *
00322  * \param ctx       HMAC context to be reset
00323  *
00324  * \returns         0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00325  *                  verification fails.
00326  */
00327 int mbedtls_md_hmac_reset( mbedtls_md_context_t *ctx );
00328 
00329 /**
00330  * \brief          Output = Generic_HMAC( hmac key, input buffer )
00331  *
00332  * \param md_info  message digest info
00333  * \param key      HMAC secret key
00334  * \param keylen   length of the HMAC key in bytes
00335  * \param input    buffer holding the  data
00336  * \param ilen     length of the input data
00337  * \param output   Generic HMAC-result
00338  *
00339  * \returns        0 on success, MBEDTLS_ERR_MD_BAD_INPUT_DATA if parameter
00340  *                 verification fails.
00341  */
00342 int mbedtls_md_hmac( const mbedtls_md_info_t *md_info, const unsigned char *key, size_t keylen,
00343                 const unsigned char *input, size_t ilen,
00344                 unsigned char *output );
00345 
00346 /* Internal use */
00347 int mbedtls_md_process( mbedtls_md_context_t *ctx, const unsigned char *data );
00348 
00349 #ifdef __cplusplus
00350 }
00351 #endif
00352 
00353 #endif /* MBEDTLS_MD_H */