common/mbedtls/md.h

   1 /**
   2 * \file md.h
   3 *
   4 * \brief This file contains the generic message-digest wrapper.
   5 *
   6 * \author Adriaan de Jong <dejong@fox-it.com>
   7 */
   8 /*
   9  *  Copyright The Mbed TLS Contributors
  10  *  SPDX-License-Identifier: Apache-2.0
  11  *
  12  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
  13  *  not use this file except in compliance with the License.
  14  *  You may obtain a copy of the License at
  15  *
  16  *  http://www.apache.org/licenses/LICENSE-2.0
  17  *
  18  *  Unless required by applicable law or agreed to in writing, software
  19  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  20  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  21  *  See the License for the specific language governing permissions and
  22  *  limitations under the License.
  23  */
  24
  25 #ifndef MBEDTLS_MD_H
  26 #define MBEDTLS_MD_H
  27
  28 #include <stddef.h>
  29
  30 #if !defined(MBEDTLS_CONFIG_FILE)
  31 #include "mbedtls/config.h"
  32 #else
  33 #include MBEDTLS_CONFIG_FILE
  34 #endif
  35
  36 #define MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE                -0x5080  /**< The selected feature is not available. */
  37 #define MBEDTLS_ERR_MD_BAD_INPUT_DATA                     -0x5100  /**< Bad input parameters to function. */
  38 #define MBEDTLS_ERR_MD_ALLOC_FAILED                       -0x5180  /**< Failed to allocate memory. */
  39 #define MBEDTLS_ERR_MD_FILE_IO_ERROR                      -0x5200  /**< Opening or reading of file failed. */
  40
  41 /* MBEDTLS_ERR_MD_HW_ACCEL_FAILED is deprecated and should not be used. */
  42 #define MBEDTLS_ERR_MD_HW_ACCEL_FAILED                    -0x5280  /**< MD hardware accelerator failed. */
  43
  44 #ifdef __cplusplus
  45 extern "C" {
  46 #endif
  47
  48 /**
  49  * \brief     Supported message digests.
  50  *
  51  * \warning   MD2, MD4, MD5 and SHA-1 are considered weak message digests and
  52  *            their use constitutes a security risk. We recommend considering
  53  *            stronger message digests instead.
  54  *
  55  */
  56 typedef enum {
  57     MBEDTLS_MD_NONE = 0,  /**< None. */
  58     MBEDTLS_MD_MD2,       /**< The MD2 message digest. */
  59     MBEDTLS_MD_MD4,       /**< The MD4 message digest. */
  60     MBEDTLS_MD_MD5,       /**< The MD5 message digest. */
  61     MBEDTLS_MD_SHA1,      /**< The SHA-1 message digest. */
  62     MBEDTLS_MD_SHA224,    /**< The SHA-224 message digest. */
  63     MBEDTLS_MD_SHA256,    /**< The SHA-256 message digest. */
  64     MBEDTLS_MD_SHA384,    /**< The SHA-384 message digest. */
  65     MBEDTLS_MD_SHA512,    /**< The SHA-512 message digest. */
  66     MBEDTLS_MD_RIPEMD160, /**< The RIPEMD-160 message digest. */
  67 } mbedtls_md_type_t;
  68
  69 #if defined(MBEDTLS_SHA512_C)
  70 #define MBEDTLS_MD_MAX_SIZE         64  /* longest known is SHA512 */
  71 #else
  72 #define MBEDTLS_MD_MAX_SIZE         32  /* longest known is SHA256 or less */
  73 #endif
  74
  75 #if defined(MBEDTLS_SHA512_C)
  76 #define MBEDTLS_MD_MAX_BLOCK_SIZE         128
  77 #else
  78 #define MBEDTLS_MD_MAX_BLOCK_SIZE         64
  79 #endif
  80
  81 /**
  82  * Opaque struct defined in md_internal.h.
  83  */
  84 typedef struct mbedtls_md_info_t mbedtls_md_info_t;
  85
  86 /**
  87  * The generic message-digest context.
  88  */
  89 typedef struct mbedtls_md_context_t {
  90     /** Information about the associated message digest. */
  91     const mbedtls_md_info_t *md_info;
  92
  93     /** The digest-specific context. */
  94     void *md_ctx;
  95
  96     /** The HMAC part of the context. */
  97     void *hmac_ctx;
  98 } mbedtls_md_context_t;
  99
 100 /**
 101  * \brief           This function returns the list of digests supported by the
 102  *                  generic digest module.
 103  *
 104  * \note            The list starts with the strongest available hashes.
 105  *
 106  * \return          A statically allocated array of digests. Each element
 107  *                  in the returned list is an integer belonging to the
 108  *                  message-digest enumeration #mbedtls_md_type_t.
 109  *                  The last entry is 0.
 110  */
 111 const int *mbedtls_md_list(void);
 112
 113 /**
 114  * \brief           This function returns the message-digest information
 115  *                  associated with the given digest name.
 116  *
 117  * \param md_name   The name of the digest to search for.
 118  *
 119  * \return          The message-digest information associated with \p md_name.
 120  * \return          NULL if the associated message-digest information is not found.
 121  */
 122 const mbedtls_md_info_t *mbedtls_md_info_from_string(const char *md_name);
 123
 124 /**
 125  * \brief           This function returns the message-digest information
 126  *                  associated with the given digest type.
 127  *
 128  * \param md_type   The type of digest to search for.
 129  *
 130  * \return          The message-digest information associated with \p md_type.
 131  * \return          NULL if the associated message-digest information is not found.
 132  */
 133 const mbedtls_md_info_t *mbedtls_md_info_from_type(mbedtls_md_type_t md_type);
 134
 135 /**
 136  * \brief           This function initializes a message-digest context without
 137  *                  binding it to a particular message-digest algorithm.
 138  *
 139  *                  This function should always be called first. It prepares the
 140  *                  context for mbedtls_md_setup() for binding it to a
 141  *                  message-digest algorithm.
 142  */
 143 void mbedtls_md_init(mbedtls_md_context_t *ctx);
 144
 145 /**
 146  * \brief           This function clears the internal structure of \p ctx and
 147  *                  frees any embedded internal structure, but does not free
 148  *                  \p ctx itself.
 149  *
 150  *                  If you have called mbedtls_md_setup() on \p ctx, you must
 151  *                  call mbedtls_md_free() when you are no longer using the
 152  *                  context.
 153  *                  Calling this function if you have previously
 154  *                  called mbedtls_md_init() and nothing else is optional.
 155  *                  You must not call this function if you have not called
 156  *                  mbedtls_md_init().
 157  */
 158 void mbedtls_md_free(mbedtls_md_context_t *ctx);
 159
 160 #if ! defined(MBEDTLS_DEPRECATED_REMOVED)
 161 #if defined(MBEDTLS_DEPRECATED_WARNING)
 162 #define MBEDTLS_DEPRECATED    __attribute__((deprecated))
 163 #else
 164 #define MBEDTLS_DEPRECATED
 165 #endif
 166 /**
 167  * \brief           This function selects the message digest algorithm to use,
 168  *                  and allocates internal structures.
 169  *
 170  *                  It should be called after mbedtls_md_init() or mbedtls_md_free().
 171  *                  Makes it necessary to call mbedtls_md_free() later.
 172  *
 173  * \deprecated      Superseded by mbedtls_md_setup() in 2.0.0
 174  *
 175  * \param ctx       The context to set up.
 176  * \param md_info   The information structure of the message-digest algorithm
 177  *                  to use.
 178  *
 179  * \return          \c 0 on success.
 180  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 181  *                  failure.
 182  * \return          #MBEDTLS_ERR_MD_ALLOC_FAILED on memory-allocation failure.
 183  */
 184 int mbedtls_md_init_ctx(mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info) MBEDTLS_DEPRECATED;
 185 #undef MBEDTLS_DEPRECATED
 186 #endif /* MBEDTLS_DEPRECATED_REMOVED */
 187
 188 /**
 189  * \brief           This function selects the message digest algorithm to use,
 190  *                  and allocates internal structures.
 191  *
 192  *                  It should be called after mbedtls_md_init() or
 193  *                  mbedtls_md_free(). Makes it necessary to call
 194  *                  mbedtls_md_free() later.
 195  *
 196  * \param ctx       The context to set up.
 197  * \param md_info   The information structure of the message-digest algorithm
 198  *                  to use.
 199  * \param hmac      Defines if HMAC is used. 0: HMAC is not used (saves some memory),
 200  *                  or non-zero: HMAC is used with this context.
 201  *
 202  * \return          \c 0 on success.
 203  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 204  *                  failure.
 205  * \return          #MBEDTLS_ERR_MD_ALLOC_FAILED on memory-allocation failure.
 206  */
 207 int mbedtls_md_setup(mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac);
 208
 209 /**
 210  * \brief           This function clones the state of an message-digest
 211  *                  context.
 212  *
 213  * \note            You must call mbedtls_md_setup() on \c dst before calling
 214  *                  this function.
 215  *
 216  * \note            The two contexts must have the same type,
 217  *                  for example, both are SHA-256.
 218  *
 219  * \warning         This function clones the message-digest state, not the
 220  *                  HMAC state.
 221  *
 222  * \param dst       The destination context.
 223  * \param src       The context to be cloned.
 224  *
 225  * \return          \c 0 on success.
 226  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification failure.
 227  */
 228 int mbedtls_md_clone(mbedtls_md_context_t *dst,
 229                      const mbedtls_md_context_t *src);
 230
 231 /**
 232  * \brief           This function extracts the message-digest size from the
 233  *                  message-digest information structure.
 234  *
 235  * \param md_info   The information structure of the message-digest algorithm
 236  *                  to use.
 237  *
 238  * \return          The size of the message-digest output in Bytes.
 239  */
 240 unsigned char mbedtls_md_get_size(const mbedtls_md_info_t *md_info);
 241
 242 /**
 243  * \brief           This function extracts the message-digest type from the
 244  *                  message-digest information structure.
 245  *
 246  * \param md_info   The information structure of the message-digest algorithm
 247  *                  to use.
 248  *
 249  * \return          The type of the message digest.
 250  */
 251 mbedtls_md_type_t mbedtls_md_get_type(const mbedtls_md_info_t *md_info);
 252
 253 /**
 254  * \brief           This function extracts the message-digest name from the
 255  *                  message-digest information structure.
 256  *
 257  * \param md_info   The information structure of the message-digest algorithm
 258  *                  to use.
 259  *
 260  * \return          The name of the message digest.
 261  */
 262 const char *mbedtls_md_get_name(const mbedtls_md_info_t *md_info);
 263
 264 /**
 265  * \brief           This function starts a message-digest computation.
 266  *
 267  *                  You must call this function after setting up the context
 268  *                  with mbedtls_md_setup(), and before passing data with
 269  *                  mbedtls_md_update().
 270  *
 271  * \param ctx       The generic message-digest context.
 272  *
 273  * \return          \c 0 on success.
 274  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 275  *                  failure.
 276  */
 277 int mbedtls_md_starts(mbedtls_md_context_t *ctx);
 278
 279 /**
 280  * \brief           This function feeds an input buffer into an ongoing
 281  *                  message-digest computation.
 282  *
 283  *                  You must call mbedtls_md_starts() before calling this
 284  *                  function. You may call this function multiple times.
 285  *                  Afterwards, call mbedtls_md_finish().
 286  *
 287  * \param ctx       The generic message-digest context.
 288  * \param input     The buffer holding the input data.
 289  * \param ilen      The length of the input data.
 290  *
 291  * \return          \c 0 on success.
 292  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 293  *                  failure.
 294  */
 295 int mbedtls_md_update(mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen);
 296
 297 /**
 298  * \brief           This function finishes the digest operation,
 299  *                  and writes the result to the output buffer.
 300  *
 301  *                  Call this function after a call to mbedtls_md_starts(),
 302  *                  followed by any number of calls to mbedtls_md_update().
 303  *                  Afterwards, you may either clear the context with
 304  *                  mbedtls_md_free(), or call mbedtls_md_starts() to reuse
 305  *                  the context for another digest operation with the same
 306  *                  algorithm.
 307  *
 308  * \param ctx       The generic message-digest context.
 309  * \param output    The buffer for the generic message-digest checksum result.
 310  *
 311  * \return          \c 0 on success.
 312  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 313  *                  failure.
 314  */
 315 int mbedtls_md_finish(mbedtls_md_context_t *ctx, unsigned char *output);
 316
 317 /**
 318  * \brief          This function calculates the message-digest of a buffer,
 319  *                 with respect to a configurable message-digest algorithm
 320  *                 in a single call.
 321  *
 322  *                 The result is calculated as
 323  *                 Output = message_digest(input buffer).
 324  *
 325  * \param md_info  The information structure of the message-digest algorithm
 326  *                 to use.
 327  * \param input    The buffer holding the data.
 328  * \param ilen     The length of the input data.
 329  * \param output   The generic message-digest checksum result.
 330  *
 331  * \return         \c 0 on success.
 332  * \return         #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 333  *                 failure.
 334  */
 335 int mbedtls_md(const mbedtls_md_info_t *md_info, const unsigned char *input, size_t ilen,
 336                unsigned char *output);
 337
 338 #if defined(MBEDTLS_FS_IO)
 339 /**
 340  * \brief          This function calculates the message-digest checksum
 341  *                 result of the contents of the provided file.
 342  *
 343  *                 The result is calculated as
 344  *                 Output = message_digest(file contents).
 345  *
 346  * \param md_info  The information structure of the message-digest algorithm
 347  *                 to use.
 348  * \param path     The input file name.
 349  * \param output   The generic message-digest checksum result.
 350  *
 351  * \return         \c 0 on success.
 352  * \return         #MBEDTLS_ERR_MD_FILE_IO_ERROR on an I/O error accessing
 353  *                 the file pointed by \p path.
 354  * \return         #MBEDTLS_ERR_MD_BAD_INPUT_DATA if \p md_info was NULL.
 355  */
 356 int mbedtls_md_file(const mbedtls_md_info_t *md_info, const char *path,
 357                     unsigned char *output);
 358 #endif /* MBEDTLS_FS_IO */
 359
 360 /**
 361  * \brief           This function sets the HMAC key and prepares to
 362  *                  authenticate a new message.
 363  *
 364  *                  Call this function after mbedtls_md_setup(), to use
 365  *                  the MD context for an HMAC calculation, then call
 366  *                  mbedtls_md_hmac_update() to provide the input data, and
 367  *                  mbedtls_md_hmac_finish() to get the HMAC value.
 368  *
 369  * \param ctx       The message digest context containing an embedded HMAC
 370  *                  context.
 371  * \param key       The HMAC secret key.
 372  * \param keylen    The length of the HMAC key in Bytes.
 373  *
 374  * \return          \c 0 on success.
 375  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 376  *                  failure.
 377  */
 378 int mbedtls_md_hmac_starts(mbedtls_md_context_t *ctx, const unsigned char *key,
 379                            size_t keylen);
 380
 381 /**
 382  * \brief           This function feeds an input buffer into an ongoing HMAC
 383  *                  computation.
 384  *
 385  *                  Call mbedtls_md_hmac_starts() or mbedtls_md_hmac_reset()
 386  *                  before calling this function.
 387  *                  You may call this function multiple times to pass the
 388  *                  input piecewise.
 389  *                  Afterwards, call mbedtls_md_hmac_finish().
 390  *
 391  * \param ctx       The message digest context containing an embedded HMAC
 392  *                  context.
 393  * \param input     The buffer holding the input data.
 394  * \param ilen      The length of the input data.
 395  *
 396  * \return          \c 0 on success.
 397  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 398  *                  failure.
 399  */
 400 int mbedtls_md_hmac_update(mbedtls_md_context_t *ctx, const unsigned char *input,
 401                            size_t ilen);
 402
 403 /**
 404  * \brief           This function finishes the HMAC operation, and writes
 405  *                  the result to the output buffer.
 406  *
 407  *                  Call this function after mbedtls_md_hmac_starts() and
 408  *                  mbedtls_md_hmac_update() to get the HMAC value. Afterwards
 409  *                  you may either call mbedtls_md_free() to clear the context,
 410  *                  or call mbedtls_md_hmac_reset() to reuse the context with
 411  *                  the same HMAC key.
 412  *
 413  * \param ctx       The message digest context containing an embedded HMAC
 414  *                  context.
 415  * \param output    The generic HMAC checksum result.
 416  *
 417  * \return          \c 0 on success.
 418  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 419  *                  failure.
 420  */
 421 int mbedtls_md_hmac_finish(mbedtls_md_context_t *ctx, unsigned char *output);
 422
 423 /**
 424  * \brief           This function prepares to authenticate a new message with
 425  *                  the same key as the previous HMAC operation.
 426  *
 427  *                  You may call this function after mbedtls_md_hmac_finish().
 428  *                  Afterwards call mbedtls_md_hmac_update() to pass the new
 429  *                  input.
 430  *
 431  * \param ctx       The message digest context containing an embedded HMAC
 432  *                  context.
 433  *
 434  * \return          \c 0 on success.
 435  * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 436  *                  failure.
 437  */
 438 int mbedtls_md_hmac_reset(mbedtls_md_context_t *ctx);
 439
 440 /**
 441  * \brief          This function calculates the full generic HMAC
 442  *                 on the input buffer with the provided key.
 443  *
 444  *                 The function allocates the context, performs the
 445  *                 calculation, and frees the context.
 446  *
 447  *                 The HMAC result is calculated as
 448  *                 output = generic HMAC(hmac key, input buffer).
 449  *
 450  * \param md_info  The information structure of the message-digest algorithm
 451  *                 to use.
 452  * \param key      The HMAC secret key.
 453  * \param keylen   The length of the HMAC secret key in Bytes.
 454  * \param input    The buffer holding the input data.
 455  * \param ilen     The length of the input data.
 456  * \param output   The generic HMAC result.
 457  *
 458  * \return         \c 0 on success.
 459  * \return         #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
 460  *                 failure.
 461  */
 462 int mbedtls_md_hmac(const mbedtls_md_info_t *md_info, const unsigned char *key, size_t keylen,
 463                     const unsigned char *input, size_t ilen,
 464                     unsigned char *output);
 465
 466 /* Internal use */
 467 int mbedtls_md_process(mbedtls_md_context_t *ctx, const unsigned char *data);
 468
 469 #ifdef __cplusplus
 470 }
 471 #endif
 472
 473 #endif /* MBEDTLS_MD_H */