diff --git a/library/psa_crypto_hash.h b/library/psa_crypto_hash.h
new file mode 100644
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--- /dev/null
+++ b/library/psa_crypto_hash.h
@@ -0,0 +1,236 @@
+/*
+ *  PSA hashing layer on top of Mbed TLS software crypto
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  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.
+ */
+
+#ifndef PSA_CRYPTO_HASH_H
+#define PSA_CRYPTO_HASH_H
+
+#include <psa/crypto.h>
+#include "mbedtls/md2.h"
+#include "mbedtls/md4.h"
+#include "mbedtls/md5.h"
+#include "mbedtls/ripemd160.h"
+#include "mbedtls/sha1.h"
+#include "mbedtls/sha256.h"
+#include "mbedtls/sha512.h"
+
+typedef struct
+{
+    psa_algorithm_t alg;
+    union
+    {
+        unsigned dummy; /* Make the union non-empty even with no supported algorithms. */
+#if defined(MBEDTLS_MD2_C)
+        mbedtls_md2_context md2;
+#endif
+#if defined(MBEDTLS_MD4_C)
+        mbedtls_md4_context md4;
+#endif
+#if defined(MBEDTLS_MD5_C)
+        mbedtls_md5_context md5;
+#endif
+#if defined(MBEDTLS_RIPEMD160_C)
+        mbedtls_ripemd160_context ripemd160;
+#endif
+#if defined(MBEDTLS_SHA1_C)
+        mbedtls_sha1_context sha1;
+#endif
+#if defined(MBEDTLS_SHA256_C)
+        mbedtls_sha256_context sha256;
+#endif
+#if defined(MBEDTLS_SHA512_C)
+        mbedtls_sha512_context sha512;
+#endif
+    } ctx;
+} mbedtls_psa_hash_operation_t;
+
+#define MBEDTLS_PSA_HASH_OPERATION_INIT {0, {0}}
+
+/** Calculate the hash (digest) of a message using Mbed TLS routines.
+ *
+ * \param alg               The hash algorithm to compute (\c PSA_ALG_XXX value
+ *                          such that #PSA_ALG_IS_HASH(\p alg) is true).
+ * \param[in] input         Buffer containing the message to hash.
+ * \param input_length      Size of the \p input buffer in bytes.
+ * \param[out] hash         Buffer where the hash is to be written.
+ * \param hash_size         Size of the \p hash buffer in bytes.
+ * \param[out] hash_length  On success, the number of bytes
+ *                          that make up the hash value. This is always
+ *                          #PSA_HASH_LENGTH(\p alg).
+ *
+ * \retval #PSA_SUCCESS
+ *         Success.
+ * \retval #PSA_ERROR_NOT_SUPPORTED
+ *         \p alg is not supported or is not a hash algorithm.
+ * \retval #PSA_ERROR_INVALID_ARGUMENT
+ * \retval #PSA_ERROR_BUFFER_TOO_SMALL
+ *         \p hash_size is too small
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ * \retval #PSA_ERROR_COMMUNICATION_FAILURE
+ * \retval #PSA_ERROR_HARDWARE_FAILURE
+ * \retval #PSA_ERROR_CORRUPTION_DETECTED
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ */
+psa_status_t mbedtls_psa_hash_compute(
+    psa_algorithm_t alg,
+    const uint8_t *input,
+    size_t input_length,
+    uint8_t *hash,
+    size_t hash_size,
+    size_t *hash_length);
+
+/** Set up a multipart hash operation using Mbed TLS routines.
+ *
+ * If an error occurs at any step after a call to mbedtls_psa_hash_setup(), the
+ * operation will need to be reset by a call to mbedtls_psa_hash_abort(). The
+ * core may call mbedtls_psa_hash_abort() at any time after the operation
+ * has been initialized.
+ *
+ * After a successful call to mbedtls_psa_hash_setup(), the core must
+ * eventually terminate the operation. The following events terminate an
+ * operation:
+ * - A successful call to mbedtls_psa_hash_finish() or mbedtls_psa_hash_verify().
+ * - A call to mbedtls_psa_hash_abort().
+ *
+ * \param[in,out] operation The operation object to set up. It must have
+ *                          been initialized to all-zero and not yet be in use.
+ * \param alg               The hash algorithm to compute (\c PSA_ALG_XXX value
+ *                          such that #PSA_ALG_IS_HASH(\p alg) is true).
+ *
+ * \retval #PSA_SUCCESS
+ *         Success.
+ * \retval #PSA_ERROR_NOT_SUPPORTED
+ *         \p alg is not a supported hash algorithm.
+ * \retval #PSA_ERROR_BAD_STATE
+ *         The operation state is not valid (it must be inactive).
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ * \retval #PSA_ERROR_CORRUPTION_DETECTED
+ */
+psa_status_t mbedtls_psa_hash_setup(
+    mbedtls_psa_hash_operation_t *operation,
+    psa_algorithm_t alg );
+
+/** Clone an Mbed TLS hash operation.
+ *
+ * This function copies the state of an ongoing hash operation to
+ * a new operation object. In other words, this function is equivalent
+ * to calling mbedtls_psa_hash_setup() on \p target_operation with the same
+ * algorithm that \p source_operation was set up for, then
+ * mbedtls_psa_hash_update() on \p target_operation with the same input that
+ * that was passed to \p source_operation. After this function returns, the
+ * two objects are independent, i.e. subsequent calls involving one of
+ * the objects do not affect the other object.
+ *
+ * \param[in] source_operation      The active hash operation to clone.
+ * \param[in,out] target_operation  The operation object to set up.
+ *                                  It must be initialized but not active.
+ *
+ * \retval #PSA_SUCCESS
+ * \retval #PSA_ERROR_BAD_STATE
+ *         The \p source_operation state is not valid (it must be active).
+ * \retval #PSA_ERROR_BAD_STATE
+ *         The \p target_operation state is not valid (it must be inactive).
+ * \retval #PSA_ERROR_CORRUPTION_DETECTED
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ */
+psa_status_t mbedtls_psa_hash_clone(
+    const mbedtls_psa_hash_operation_t *source_operation,
+    mbedtls_psa_hash_operation_t *target_operation );
+
+/** Add a message fragment to a multipart Mbed TLS hash operation.
+ *
+ * The application must call mbedtls_psa_hash_setup() before calling this function.
+ *
+ * If this function returns an error status, the operation enters an error
+ * state and must be aborted by calling mbedtls_psa_hash_abort().
+ *
+ * \param[in,out] operation Active hash operation.
+ * \param[in] input         Buffer containing the message fragment to hash.
+ * \param input_length      Size of the \p input buffer in bytes.
+ *
+ * \retval #PSA_SUCCESS
+ *         Success.
+ * \retval #PSA_ERROR_BAD_STATE
+ *         The operation state is not valid (it muct be active).
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ * \retval #PSA_ERROR_CORRUPTION_DETECTED
+ */
+psa_status_t mbedtls_psa_hash_update(
+    mbedtls_psa_hash_operation_t *operation,
+    const uint8_t *input,
+    size_t input_length );
+
+/** Finish the calculation of the Mbed TLS-calculated hash of a message.
+ *
+ * The application must call mbedtls_psa_hash_setup() before calling this function.
+ * This function calculates the hash of the message formed by concatenating
+ * the inputs passed to preceding calls to mbedtls_psa_hash_update().
+ *
+ * When this function returns successfuly, the operation becomes inactive.
+ * If this function returns an error status, the operation enters an error
+ * state and must be aborted by calling mbedtls_psa_hash_abort().
+ *
+ * \param[in,out] operation     Active hash operation.
+ * \param[out] hash             Buffer where the hash is to be written.
+ * \param hash_size             Size of the \p hash buffer in bytes.
+ * \param[out] hash_length      On success, the number of bytes
+ *                              that make up the hash value. This is always
+ *                              #PSA_HASH_LENGTH(\c alg) where \c alg is the
+ *                              hash algorithm that is calculated.
+ *
+ * \retval #PSA_SUCCESS
+ *         Success.
+ * \retval #PSA_ERROR_BAD_STATE
+ *         The operation state is not valid (it must be active).
+ * \retval #PSA_ERROR_BUFFER_TOO_SMALL
+ *         The size of the \p hash buffer is too small. You can determine a
+ *         sufficient buffer size by calling #PSA_HASH_LENGTH(\c alg)
+ *         where \c alg is the hash algorithm that is calculated.
+ * \retval #PSA_ERROR_INSUFFICIENT_MEMORY
+ * \retval #PSA_ERROR_CORRUPTION_DETECTED
+ */
+psa_status_t mbedtls_psa_hash_finish(
+    mbedtls_psa_hash_operation_t *operation,
+    uint8_t *hash,
+    size_t hash_size,
+    size_t *hash_length );
+
+/** Abort an Mbed TLS hash operation.
+ *
+ * Aborting an operation frees all associated resources except for the
+ * \p operation structure itself. Once aborted, the operation object
+ * can be reused for another operation by calling
+ * mbedtls_psa_hash_setup() again.
+ *
+ * You may call this function any time after the operation object has
+ * been initialized by one of the methods described in #psa_hash_operation_t.
+ *
+ * In particular, calling mbedtls_psa_hash_abort() after the operation has been
+ * terminated by a call to mbedtls_psa_hash_abort(), mbedtls_psa_hash_finish() or
+ * mbedtls_psa_hash_verify() is safe and has no effect.
+ *
+ * \param[in,out] operation     Initialized hash operation.
+ *
+ * \retval #PSA_SUCCESS
+ * \retval #PSA_ERROR_CORRUPTION_DETECTED
+ */
+psa_status_t mbedtls_psa_hash_abort(
+    mbedtls_psa_hash_operation_t *operation );
+
+#endif /* PSA_CRYPTO_HASH_H */