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diff --git a/include/mbedtls/md.h b/include/mbedtls/md.h
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+/**
+ * \file md.h
+ *
+ * \brief   This file contains the generic functions for message-digest
+ *          (hashing) and HMAC.
+ *
+ * \author Adriaan de Jong <dejong@fox-it.com>
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#ifndef MBEDTLS_MD_H
+#define MBEDTLS_MD_H
+#include "mbedtls/private_access.h"
+
+#include <stddef.h>
+
+#include "mbedtls/build_info.h"
+#include "mbedtls/platform_util.h"
+
+#if defined(MBEDTLS_MD_LIGHT)
+
+/*
+ * - MBEDTLS_MD_CAN_xxx is defined if the md module can perform xxx.
+ * - MBEDTLS_MD_xxx_VIA_PSA is defined if the md module may perform xxx via PSA
+ *   (see below).
+ * - MBEDTLS_MD_SOME_PSA is defined if at least one algorithm may be performed
+ *   via PSA (see below).
+ * - MBEDTLS_MD_SOME_LEGACY is defined if at least one algorithm may be performed
+ *   via a direct legacy call (see below).
+ *
+ * The md module performs an algorithm via PSA if there is a PSA hash
+ * accelerator and the PSA driver subsytem is initialized at the time the
+ * operation is started, and makes a direct legacy call otherwise.
+ */
+
+/* PSA accelerated implementations */
+#if defined(MBEDTLS_PSA_CRYPTO_C)
+#if defined(MBEDTLS_PSA_ACCEL_ALG_MD5)
+#define MBEDTLS_MD_CAN_MD5
+#define MBEDTLS_MD_MD5_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA_1)
+#define MBEDTLS_MD_CAN_SHA1
+#define MBEDTLS_MD_SHA1_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA_224)
+#define MBEDTLS_MD_CAN_SHA224
+#define MBEDTLS_MD_SHA224_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA_256)
+#define MBEDTLS_MD_CAN_SHA256
+#define MBEDTLS_MD_SHA256_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA_384)
+#define MBEDTLS_MD_CAN_SHA384
+#define MBEDTLS_MD_SHA384_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA_512)
+#define MBEDTLS_MD_CAN_SHA512
+#define MBEDTLS_MD_SHA512_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_RIPEMD160)
+#define MBEDTLS_MD_CAN_RIPEMD160
+#define MBEDTLS_MD_RIPEMD160_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA3_224)
+#define MBEDTLS_MD_CAN_SHA3_224
+#define MBEDTLS_MD_SHA3_224_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA3_256)
+#define MBEDTLS_MD_CAN_SHA3_256
+#define MBEDTLS_MD_SHA3_256_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA3_384)
+#define MBEDTLS_MD_CAN_SHA3_384
+#define MBEDTLS_MD_SHA3_384_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#if defined(MBEDTLS_PSA_ACCEL_ALG_SHA3_512)
+#define MBEDTLS_MD_CAN_SHA3_512
+#define MBEDTLS_MD_SHA3_512_VIA_PSA
+#define MBEDTLS_MD_SOME_PSA
+#endif
+#endif /* MBEDTLS_PSA_CRYPTO_C */
+
+/* Built-in implementations */
+#if defined(MBEDTLS_MD5_C)
+#define MBEDTLS_MD_CAN_MD5
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_SHA1_C)
+#define MBEDTLS_MD_CAN_SHA1
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_SHA224_C)
+#define MBEDTLS_MD_CAN_SHA224
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_SHA256_C)
+#define MBEDTLS_MD_CAN_SHA256
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_SHA384_C)
+#define MBEDTLS_MD_CAN_SHA384
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_SHA512_C)
+#define MBEDTLS_MD_CAN_SHA512
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_SHA3_C)
+#define MBEDTLS_MD_CAN_SHA3_224
+#define MBEDTLS_MD_CAN_SHA3_256
+#define MBEDTLS_MD_CAN_SHA3_384
+#define MBEDTLS_MD_CAN_SHA3_512
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+#if defined(MBEDTLS_RIPEMD160_C)
+#define MBEDTLS_MD_CAN_RIPEMD160
+#define MBEDTLS_MD_SOME_LEGACY
+#endif
+
+#endif /* MBEDTLS_MD_LIGHT */
+
+/** The selected feature is not available. */
+#define MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE                -0x5080
+/** Bad input parameters to function. */
+#define MBEDTLS_ERR_MD_BAD_INPUT_DATA                     -0x5100
+/** Failed to allocate memory. */
+#define MBEDTLS_ERR_MD_ALLOC_FAILED                       -0x5180
+/** Opening or reading of file failed. */
+#define MBEDTLS_ERR_MD_FILE_IO_ERROR                      -0x5200
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief     Supported message digests.
+ *
+ * \warning   MD5 and SHA-1 are considered weak message digests and
+ *            their use constitutes a security risk. We recommend considering
+ *            stronger message digests instead.
+ *
+ */
+/* Note: these are aligned with the definitions of PSA_ALG_ macros for hashes,
+ * in order to enable an efficient implementation of conversion functions.
+ * This is tested by md_to_from_psa() in test_suite_md. */
+typedef enum {
+    MBEDTLS_MD_NONE=0,    /**< None. */
+    MBEDTLS_MD_MD5=0x03,       /**< The MD5 message digest. */
+    MBEDTLS_MD_RIPEMD160=0x04, /**< The RIPEMD-160 message digest. */
+    MBEDTLS_MD_SHA1=0x05,      /**< The SHA-1 message digest. */
+    MBEDTLS_MD_SHA224=0x08,    /**< The SHA-224 message digest. */
+    MBEDTLS_MD_SHA256=0x09,    /**< The SHA-256 message digest. */
+    MBEDTLS_MD_SHA384=0x0a,    /**< The SHA-384 message digest. */
+    MBEDTLS_MD_SHA512=0x0b,    /**< The SHA-512 message digest. */
+    MBEDTLS_MD_SHA3_224=0x10,  /**< The SHA3-224 message digest. */
+    MBEDTLS_MD_SHA3_256=0x11,  /**< The SHA3-256 message digest. */
+    MBEDTLS_MD_SHA3_384=0x12,  /**< The SHA3-384 message digest. */
+    MBEDTLS_MD_SHA3_512=0x13,  /**< The SHA3-512 message digest. */
+} mbedtls_md_type_t;
+
+/* Note: this should always be >= PSA_HASH_MAX_SIZE
+ * in all builds with both CRYPTO_C and MD_LIGHT.
+ *
+ * This is to make things easier for modules such as TLS that may define a
+ * buffer size using MD_MAX_SIZE in a part of the code that's common to PSA
+ * and legacy, then assume the buffer's size is PSA_HASH_MAX_SIZE in another
+ * part of the code based on PSA.
+ */
+#if defined(MBEDTLS_MD_CAN_SHA512) || defined(MBEDTLS_MD_CAN_SHA3_512)
+#define MBEDTLS_MD_MAX_SIZE         64  /* longest known is SHA512 */
+#elif defined(MBEDTLS_MD_CAN_SHA384) || defined(MBEDTLS_MD_CAN_SHA3_384)
+#define MBEDTLS_MD_MAX_SIZE         48  /* longest known is SHA384 */
+#elif defined(MBEDTLS_MD_CAN_SHA256) || defined(MBEDTLS_MD_CAN_SHA3_256)
+#define MBEDTLS_MD_MAX_SIZE         32  /* longest known is SHA256 */
+#elif defined(MBEDTLS_MD_CAN_SHA224) || defined(MBEDTLS_MD_CAN_SHA3_224)
+#define MBEDTLS_MD_MAX_SIZE         28  /* longest known is SHA224 */
+#else
+#define MBEDTLS_MD_MAX_SIZE         20  /* longest known is SHA1 or RIPE MD-160
+                                           or smaller (MD5 and earlier) */
+#endif
+
+#if defined(MBEDTLS_MD_CAN_SHA3_224)
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         144 /* the longest known is SHA3-224 */
+#elif defined(MBEDTLS_MD_CAN_SHA3_256)
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         136
+#elif defined(MBEDTLS_MD_CAN_SHA512) || defined(MBEDTLS_MD_CAN_SHA384)
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         128
+#elif defined(MBEDTLS_MD_CAN_SHA3_384)
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         104
+#elif defined(MBEDTLS_MD_CAN_SHA3_512)
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         72
+#else
+#define MBEDTLS_MD_MAX_BLOCK_SIZE         64
+#endif
+
+/**
+ * Opaque struct.
+ *
+ * Constructed using either #mbedtls_md_info_from_string or
+ * #mbedtls_md_info_from_type.
+ *
+ * Fields can be accessed with #mbedtls_md_get_size,
+ * #mbedtls_md_get_type and #mbedtls_md_get_name.
+ */
+/* Defined internally in library/md_wrap.h. */
+typedef struct mbedtls_md_info_t mbedtls_md_info_t;
+
+/**
+ * Used internally to indicate whether a context uses legacy or PSA.
+ *
+ * Internal use only.
+ */
+typedef enum {
+    MBEDTLS_MD_ENGINE_LEGACY = 0,
+    MBEDTLS_MD_ENGINE_PSA,
+} mbedtls_md_engine_t;
+
+/**
+ * The generic message-digest context.
+ */
+typedef struct mbedtls_md_context_t {
+    /** Information about the associated message digest. */
+    const mbedtls_md_info_t *MBEDTLS_PRIVATE(md_info);
+
+#if defined(MBEDTLS_MD_SOME_PSA)
+    /** Are hash operations dispatched to PSA or legacy? */
+    mbedtls_md_engine_t MBEDTLS_PRIVATE(engine);
+#endif
+
+    /** The digest-specific context (legacy) or the PSA operation. */
+    void *MBEDTLS_PRIVATE(md_ctx);
+
+#if defined(MBEDTLS_MD_C)
+    /** The HMAC part of the context. */
+    void *MBEDTLS_PRIVATE(hmac_ctx);
+#endif
+} mbedtls_md_context_t;
+
+/**
+ * \brief           This function returns the message-digest information
+ *                  associated with the given digest type.
+ *
+ * \param md_type   The type of digest to search for.
+ *
+ * \return          The message-digest information associated with \p md_type.
+ * \return          NULL if the associated message-digest information is not found.
+ */
+const mbedtls_md_info_t *mbedtls_md_info_from_type(mbedtls_md_type_t md_type);
+
+/**
+ * \brief           This function initializes a message-digest context without
+ *                  binding it to a particular message-digest algorithm.
+ *
+ *                  This function should always be called first. It prepares the
+ *                  context for mbedtls_md_setup() for binding it to a
+ *                  message-digest algorithm.
+ */
+void mbedtls_md_init(mbedtls_md_context_t *ctx);
+
+/**
+ * \brief           This function clears the internal structure of \p ctx and
+ *                  frees any embedded internal structure, but does not free
+ *                  \p ctx itself.
+ *
+ *                  If you have called mbedtls_md_setup() on \p ctx, you must
+ *                  call mbedtls_md_free() when you are no longer using the
+ *                  context.
+ *                  Calling this function if you have previously
+ *                  called mbedtls_md_init() and nothing else is optional.
+ *                  You must not call this function if you have not called
+ *                  mbedtls_md_init().
+ */
+void mbedtls_md_free(mbedtls_md_context_t *ctx);
+
+
+/**
+ * \brief           This function selects the message digest algorithm to use,
+ *                  and allocates internal structures.
+ *
+ *                  It should be called after mbedtls_md_init() or
+ *                  mbedtls_md_free(). Makes it necessary to call
+ *                  mbedtls_md_free() later.
+ *
+ * \param ctx       The context to set up.
+ * \param md_info   The information structure of the message-digest algorithm
+ *                  to use.
+ * \param hmac      Defines if HMAC is used. 0: HMAC is not used (saves some memory),
+ *                  or non-zero: HMAC is used with this context.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ * \return          #MBEDTLS_ERR_MD_ALLOC_FAILED on memory-allocation failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_setup(mbedtls_md_context_t *ctx, const mbedtls_md_info_t *md_info, int hmac);
+
+/**
+ * \brief           This function clones the state of a message-digest
+ *                  context.
+ *
+ * \note            You must call mbedtls_md_setup() on \c dst before calling
+ *                  this function.
+ *
+ * \note            The two contexts must have the same type,
+ *                  for example, both are SHA-256.
+ *
+ * \warning         This function clones the message-digest state, not the
+ *                  HMAC state.
+ *
+ * \param dst       The destination context.
+ * \param src       The context to be cloned.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification failure.
+ * \return          #MBEDTLS_ERR_MD_FEATURE_UNAVAILABLE if both contexts are
+ *                  not using the same engine. This can be avoided by moving
+ *                  the call to psa_crypto_init() before the first call to
+ *                  mbedtls_md_setup().
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_clone(mbedtls_md_context_t *dst,
+                     const mbedtls_md_context_t *src);
+
+/**
+ * \brief           This function extracts the message-digest size from the
+ *                  message-digest information structure.
+ *
+ * \param md_info   The information structure of the message-digest algorithm
+ *                  to use.
+ *
+ * \return          The size of the message-digest output in Bytes.
+ */
+unsigned char mbedtls_md_get_size(const mbedtls_md_info_t *md_info);
+
+/**
+ * \brief           This function gives the message-digest size associated to
+ *                  message-digest type.
+ *
+ * \param md_type   The message-digest type.
+ *
+ * \return          The size of the message-digest output in Bytes,
+ *                  or 0 if the message-digest type is not known.
+ */
+static inline unsigned char mbedtls_md_get_size_from_type(mbedtls_md_type_t md_type)
+{
+    return mbedtls_md_get_size(mbedtls_md_info_from_type(md_type));
+}
+
+/**
+ * \brief           This function extracts the message-digest type from the
+ *                  message-digest information structure.
+ *
+ * \param md_info   The information structure of the message-digest algorithm
+ *                  to use.
+ *
+ * \return          The type of the message digest.
+ */
+mbedtls_md_type_t mbedtls_md_get_type(const mbedtls_md_info_t *md_info);
+
+/**
+ * \brief           This function starts a message-digest computation.
+ *
+ *                  You must call this function after setting up the context
+ *                  with mbedtls_md_setup(), and before passing data with
+ *                  mbedtls_md_update().
+ *
+ * \param ctx       The generic message-digest context.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_starts(mbedtls_md_context_t *ctx);
+
+/**
+ * \brief           This function feeds an input buffer into an ongoing
+ *                  message-digest computation.
+ *
+ *                  You must call mbedtls_md_starts() before calling this
+ *                  function. You may call this function multiple times.
+ *                  Afterwards, call mbedtls_md_finish().
+ *
+ * \param ctx       The generic message-digest context.
+ * \param input     The buffer holding the input data.
+ * \param ilen      The length of the input data.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_update(mbedtls_md_context_t *ctx, const unsigned char *input, size_t ilen);
+
+/**
+ * \brief           This function finishes the digest operation,
+ *                  and writes the result to the output buffer.
+ *
+ *                  Call this function after a call to mbedtls_md_starts(),
+ *                  followed by any number of calls to mbedtls_md_update().
+ *                  Afterwards, you may either clear the context with
+ *                  mbedtls_md_free(), or call mbedtls_md_starts() to reuse
+ *                  the context for another digest operation with the same
+ *                  algorithm.
+ *
+ * \param ctx       The generic message-digest context.
+ * \param output    The buffer for the generic message-digest checksum result.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_finish(mbedtls_md_context_t *ctx, unsigned char *output);
+
+/**
+ * \brief          This function calculates the message-digest of a buffer,
+ *                 with respect to a configurable message-digest algorithm
+ *                 in a single call.
+ *
+ *                 The result is calculated as
+ *                 Output = message_digest(input buffer).
+ *
+ * \param md_info  The information structure of the message-digest algorithm
+ *                 to use.
+ * \param input    The buffer holding the data.
+ * \param ilen     The length of the input data.
+ * \param output   The generic message-digest checksum result.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                 failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md(const mbedtls_md_info_t *md_info, const unsigned char *input, size_t ilen,
+               unsigned char *output);
+
+/**
+ * \brief           This function returns the list of digests supported by the
+ *                  generic digest module.
+ *
+ * \note            The list starts with the strongest available hashes.
+ *
+ * \return          A statically allocated array of digests. Each element
+ *                  in the returned list is an integer belonging to the
+ *                  message-digest enumeration #mbedtls_md_type_t.
+ *                  The last entry is 0.
+ */
+const int *mbedtls_md_list(void);
+
+/**
+ * \brief           This function returns the message-digest information
+ *                  associated with the given digest name.
+ *
+ * \param md_name   The name of the digest to search for.
+ *
+ * \return          The message-digest information associated with \p md_name.
+ * \return          NULL if the associated message-digest information is not found.
+ */
+const mbedtls_md_info_t *mbedtls_md_info_from_string(const char *md_name);
+
+/**
+ * \brief           This function returns the name of the message digest for
+ *                  the message-digest information structure given.
+ *
+ * \param md_info   The information structure of the message-digest algorithm
+ *                  to use.
+ *
+ * \return          The name of the message digest.
+ */
+const char *mbedtls_md_get_name(const mbedtls_md_info_t *md_info);
+
+/**
+ * \brief           This function returns the message-digest information
+ *                  from the given context.
+ *
+ * \param ctx       The context from which to extract the information.
+ *                  This must be initialized (or \c NULL).
+ *
+ * \return          The message-digest information associated with \p ctx.
+ * \return          \c NULL if \p ctx is \c NULL.
+ */
+const mbedtls_md_info_t *mbedtls_md_info_from_ctx(
+    const mbedtls_md_context_t *ctx);
+
+#if defined(MBEDTLS_FS_IO)
+/**
+ * \brief          This function calculates the message-digest checksum
+ *                 result of the contents of the provided file.
+ *
+ *                 The result is calculated as
+ *                 Output = message_digest(file contents).
+ *
+ * \param md_info  The information structure of the message-digest algorithm
+ *                 to use.
+ * \param path     The input file name.
+ * \param output   The generic message-digest checksum result.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_MD_FILE_IO_ERROR on an I/O error accessing
+ *                 the file pointed by \p path.
+ * \return         #MBEDTLS_ERR_MD_BAD_INPUT_DATA if \p md_info was NULL.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_file(const mbedtls_md_info_t *md_info, const char *path,
+                    unsigned char *output);
+#endif /* MBEDTLS_FS_IO */
+
+/**
+ * \brief           This function sets the HMAC key and prepares to
+ *                  authenticate a new message.
+ *
+ *                  Call this function after mbedtls_md_setup(), to use
+ *                  the MD context for an HMAC calculation, then call
+ *                  mbedtls_md_hmac_update() to provide the input data, and
+ *                  mbedtls_md_hmac_finish() to get the HMAC value.
+ *
+ * \param ctx       The message digest context containing an embedded HMAC
+ *                  context.
+ * \param key       The HMAC secret key.
+ * \param keylen    The length of the HMAC key in Bytes.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_hmac_starts(mbedtls_md_context_t *ctx, const unsigned char *key,
+                           size_t keylen);
+
+/**
+ * \brief           This function feeds an input buffer into an ongoing HMAC
+ *                  computation.
+ *
+ *                  Call mbedtls_md_hmac_starts() or mbedtls_md_hmac_reset()
+ *                  before calling this function.
+ *                  You may call this function multiple times to pass the
+ *                  input piecewise.
+ *                  Afterwards, call mbedtls_md_hmac_finish().
+ *
+ * \param ctx       The message digest context containing an embedded HMAC
+ *                  context.
+ * \param input     The buffer holding the input data.
+ * \param ilen      The length of the input data.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_hmac_update(mbedtls_md_context_t *ctx, const unsigned char *input,
+                           size_t ilen);
+
+/**
+ * \brief           This function finishes the HMAC operation, and writes
+ *                  the result to the output buffer.
+ *
+ *                  Call this function after mbedtls_md_hmac_starts() and
+ *                  mbedtls_md_hmac_update() to get the HMAC value. Afterwards
+ *                  you may either call mbedtls_md_free() to clear the context,
+ *                  or call mbedtls_md_hmac_reset() to reuse the context with
+ *                  the same HMAC key.
+ *
+ * \param ctx       The message digest context containing an embedded HMAC
+ *                  context.
+ * \param output    The generic HMAC checksum result.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_hmac_finish(mbedtls_md_context_t *ctx, unsigned char *output);
+
+/**
+ * \brief           This function prepares to authenticate a new message with
+ *                  the same key as the previous HMAC operation.
+ *
+ *                  You may call this function after mbedtls_md_hmac_finish().
+ *                  Afterwards call mbedtls_md_hmac_update() to pass the new
+ *                  input.
+ *
+ * \param ctx       The message digest context containing an embedded HMAC
+ *                  context.
+ *
+ * \return          \c 0 on success.
+ * \return          #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                  failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_hmac_reset(mbedtls_md_context_t *ctx);
+
+/**
+ * \brief          This function calculates the full generic HMAC
+ *                 on the input buffer with the provided key.
+ *
+ *                 The function allocates the context, performs the
+ *                 calculation, and frees the context.
+ *
+ *                 The HMAC result is calculated as
+ *                 output = generic HMAC(hmac key, input buffer).
+ *
+ * \param md_info  The information structure of the message-digest algorithm
+ *                 to use.
+ * \param key      The HMAC secret key.
+ * \param keylen   The length of the HMAC secret key in Bytes.
+ * \param input    The buffer holding the input data.
+ * \param ilen     The length of the input data.
+ * \param output   The generic HMAC result.
+ *
+ * \return         \c 0 on success.
+ * \return         #MBEDTLS_ERR_MD_BAD_INPUT_DATA on parameter-verification
+ *                 failure.
+ */
+MBEDTLS_CHECK_RETURN_TYPICAL
+int mbedtls_md_hmac(const mbedtls_md_info_t *md_info, const unsigned char *key, size_t keylen,
+                    const unsigned char *input, size_t ilen,
+                    unsigned char *output);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MBEDTLS_MD_H */