diff --git a/TESTS/mbedtls/multi/main.cpp b/TESTS/mbedtls/multi/main.cpp
new file mode 100644
index 00000000000..ce823cadcd4
--- /dev/null
+++ b/TESTS/mbedtls/multi/main.cpp
@@ -0,0 +1,167 @@
+/*
+ * Copyright (c) 2013-2016, ARM Limited, All Rights Reserved
+ * 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.
+ */
+#include <stdio.h>
+#include <string.h>
+#include "mbed.h"
+#include "greentea-client/test_env.h"
+#include "unity/unity.h"
+#include "utest/utest.h"
+
+#include "mbedtls/sha256.h"
+
+
+using namespace utest::v1;
+
+#if defined(MBEDTLS_SHA256_C)
+/* Tests several call to mbedtls_sha256_update function that are not modulo 64 bytes */
+void test_case_sha256_split() {
+  const unsigned char test_buf[] = {"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopqabcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopqabcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"};
+  // sha256_output_values for 3*abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq
+  const unsigned char test_sum[] =
+  { 0x50, 0xEA, 0x82, 0x5D, 0x96, 0x84, 0xF4, 0x22,
+    0x9C, 0xA2, 0x9F, 0x1F, 0xEC, 0x51, 0x15, 0x93,
+    0xE2, 0x81, 0xE4, 0x6A, 0x14, 0x0D, 0x81, 0xE0,
+    0x00, 0x5F, 0x8F, 0x68, 0x86, 0x69, 0xA0, 0x6C};
+  unsigned char outsum[32];
+  int i;
+
+  mbedtls_sha256_context ctx;
+  printf("test sha256\n");
+  mbedtls_sha256_init( &ctx );
+  mbedtls_sha256_starts( &ctx, 0);
+  #if 0
+    printf("test not splitted\n");
+    mbedtls_sha256_update( &ctx, test_buf, 168 );
+  #else
+    printf("test splitted into 3 pieces\n");
+    mbedtls_sha256_update( &ctx, test_buf, 2 );
+    mbedtls_sha256_update( &ctx, test_buf+2, 66 );
+    mbedtls_sha256_update( &ctx, test_buf+68, 100 );
+  #endif
+  
+    mbedtls_sha256_finish( &ctx, outsum );
+    mbedtls_sha256_free( &ctx );
+  
+    printf("\nreceived result : ");
+    for (i=0;i<32;i++) { printf("%02X",outsum[i]);}
+    printf("\nawaited result  : 50EA825D9684F4229CA29F1FEC511593E281E46A140D81E0005F8F688669A06C\n"); // for  abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq
+  
+    printf("\nend of test sha256\n");
+  TEST_ASSERT_EQUAL_UINT8_ARRAY(outsum, test_sum,32);
+}
+
+/* Tests that treating 2 sha256 objects in // does not impact the result */
+void test_case_sha256_multi() {
+    const unsigned char test_buf[] = {"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopqabcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopqabcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"};
+    const unsigned char test_buf2[] = {"abcdefghijklmnopqrstuvwxyz012345678901234567890123456789"};
+
+    // sha256_output_values for abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq
+    const unsigned char test_sum1[] =
+    { 0x24, 0x8D, 0x6A, 0x61, 0xD2, 0x06, 0x38, 0xB8,
+      0xE5, 0xC0, 0x26, 0x93, 0x0C, 0x3E, 0x60, 0x39,
+      0xA3, 0x3C, 0xE4, 0x59, 0x64, 0xFF, 0x21, 0x67,
+      0xF6, 0xEC, 0xED, 0xD4, 0x19, 0xDB, 0x06, 0xC1 };
+    // sha256_output_values for 3*abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq
+    const unsigned char test_sum2[] =
+    { 0x50, 0xEA, 0x82, 0x5D, 0x96, 0x84, 0xF4, 0x22,
+      0x9C, 0xA2, 0x9F, 0x1F, 0xEC, 0x51, 0x15, 0x93,
+      0xE2, 0x81, 0xE4, 0x6A, 0x14, 0x0D, 0x81, 0xE0,
+      0x00, 0x5F, 0x8F, 0x68, 0x86, 0x69, 0xA0, 0x6C};
+    // sha256_output_values for abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopqabcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopqabcdefghijklmnopqrstuvwxyz012345678901234567890123456789
+    const unsigned char test_sum3[] =
+    { 0x6D, 0x5D, 0xDB, 0x5F, 0x4A, 0x94, 0xAB, 0x7E,
+      0x5C, 0xF7, 0x9A, 0xD8, 0x3F, 0x58, 0xD3, 0x97,
+      0xFE, 0x79, 0xFB, 0x0D, 0x79, 0xB2, 0x0D, 0x22,
+      0xFF, 0x95, 0x9F, 0x04, 0xA2, 0xE4, 0x6C, 0x68};
+    unsigned char outsum1[32], outsum2[32], outsum3[32];
+    int i;
+
+    mbedtls_sha256_context ctx1;
+    mbedtls_sha256_context ctx2;
+    mbedtls_sha256_context ctx3;
+    printf("test sha256_multi\n");
+    //Init both contexts
+    mbedtls_sha256_init( &ctx1);
+    mbedtls_sha256_init( &ctx2);
+    mbedtls_sha256_init( &ctx3);
+    //Start both contexts
+    mbedtls_sha256_starts( &ctx1, 0);
+    mbedtls_sha256_starts( &ctx2, 0);
+
+    printf("upd ctx1\n");
+    mbedtls_sha256_update( &ctx1, test_buf, 56 );
+    printf("upd ctx2\n");
+    mbedtls_sha256_update( &ctx2, test_buf, 66 );
+    printf("finish ctx1\n");
+    mbedtls_sha256_finish( &ctx1, outsum1 );
+    printf("upd ctx2\n");
+    mbedtls_sha256_update( &ctx2, test_buf+66, 46 );
+    printf("clone ctx2 in ctx3\n");
+    mbedtls_sha256_clone(&ctx3, (const mbedtls_sha256_context *)&ctx2);
+    printf("free ctx1\n");
+    mbedtls_sha256_free( &ctx1 );
+    printf("upd ctx2\n");
+    mbedtls_sha256_update( &ctx2, test_buf+112, 56 );
+    printf("upd ctx3 with different values than ctx2\n");
+    mbedtls_sha256_update( &ctx3, test_buf2, 56 );
+    printf("finish ctx2\n");
+    mbedtls_sha256_finish( &ctx2, outsum2 );
+    printf("finish ctx3\n");
+    mbedtls_sha256_finish( &ctx3, outsum3 );
+    printf("free ctx2\n");
+    mbedtls_sha256_free( &ctx2 );
+    printf("free ctx3\n");
+    mbedtls_sha256_free( &ctx3 );
+
+    printf("\nreceived result ctx1 : ");
+    for (i=0;i<32;i++) { printf("%02X",outsum1[i]);}
+    printf("\nawaited result       : 248D6A61D20638B8E5C026930C3E6039A33CE45964FF216F6ECEDD19DB06C1\n"); // for  abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq
+    printf("\nreceived result ctx2 : ");
+    for (i=0;i<32;i++) { printf("%02X",outsum2[i]);}
+    printf("\nawaited result       : 50EA825D9684F4229CA29F1FEC511593E281E46A140D81E0005F8F688669A06C\n"); // for  3*abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq
+    printf("\nreceived result ctx3 : ");
+    for (i=0;i<32;i++) { printf("%02X",outsum3[i]);}
+    printf("\nawaited result       : 6D5DDB5F4A94AB7E5CF79AD83F58D397FE79FB0D79B20D22FF959F04A2E46C68\n"); // for 2*abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq+3*0123456789
+    printf("\nend of test sha256\n");
+    TEST_ASSERT_EQUAL_UINT8_ARRAY(outsum1, test_sum1,32);
+    TEST_ASSERT_EQUAL_UINT8_ARRAY(outsum2, test_sum2,32);
+    TEST_ASSERT_EQUAL_UINT8_ARRAY(outsum3, test_sum3,32);
+}
+#endif //MBEDTLS_SHA256_C
+
+utest::v1::status_t greentea_failure_handler(const Case *const source, const failure_t reason) {
+    greentea_case_failure_abort_handler(source, reason);
+    return STATUS_CONTINUE;
+}
+
+Case cases[] = {
+#if defined(MBEDTLS_SHA256_C)
+    Case("Crypto: sha256_split", test_case_sha256_split, greentea_failure_handler),
+    Case("Crypto: sha256_multi", test_case_sha256_multi, greentea_failure_handler),
+#endif
+};
+
+utest::v1::status_t greentea_test_setup(const size_t number_of_cases) {
+    GREENTEA_SETUP(10, "default_auto");
+    return greentea_test_setup_handler(number_of_cases);
+}
+
+Specification specification(greentea_test_setup, cases, greentea_test_teardown_handler);
+
+int main() {
+    Harness::run(specification);
+}
diff --git a/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F439ZI/mbedtls_device.h b/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F439ZI/mbedtls_device.h
index 99fc5846339..c78d135083f 100644
--- a/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F439ZI/mbedtls_device.h
+++ b/features/mbedtls/targets/TARGET_STM/TARGET_STM32F4/TARGET_NUCLEO_F439ZI/mbedtls_device.h
@@ -21,6 +21,9 @@
 #define MBEDTLS_DEVICE_H
 
 #define MBEDTLS_AES_ALT
+
+#define MBEDTLS_SHA256_ALT
+
 #define MBEDTLS_SHA1_ALT
 
 #endif /* MBEDTLS_DEVICE_H */
diff --git a/features/mbedtls/targets/TARGET_STM/sha256_alt.c b/features/mbedtls/targets/TARGET_STM/sha256_alt.c
new file mode 100644
index 00000000000..a3354e9968a
--- /dev/null
+++ b/features/mbedtls/targets/TARGET_STM/sha256_alt.c
@@ -0,0 +1,217 @@
+/*
+ *  sha256_alt.c for SHA256 HASH
+ *******************************************************************************
+ * Copyright (c) 2017, STMicroelectronics
+ *  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.
+ *
+ */
+#include "mbedtls/sha256.h"
+
+#if defined(MBEDTLS_SHA256_ALT)
+#include "mbedtls/platform.h"
+
+/* Implementation that should never be optimized out by the compiler */
+static void mbedtls_zeroize( void *v, size_t n ) {
+    volatile unsigned char *p = v; while( n-- ) *p++ = 0;
+}
+
+static int st_sha256_restore_hw_context(mbedtls_sha256_context *ctx)
+{
+    uint32_t i;
+    uint32_t tickstart;
+    /* allow multi-instance of HASH use: save context for HASH HW module CR */
+    /* Check that there is no HASH activity on going */
+    tickstart = HAL_GetTick();
+    while ((HASH->SR & (HASH_FLAG_BUSY | HASH_FLAG_DMAS)) != 0) {
+        if ((HAL_GetTick() - tickstart) > ST_SHA256_TIMEOUT) {
+            return 0; // timeout: HASH processor is busy
+        }
+    }
+    HASH->STR = ctx->ctx_save_str;
+    HASH->CR = (ctx->ctx_save_cr | HASH_CR_INIT);
+    for (i=0;i<38;i++) {
+        HASH->CSR[i] = ctx->ctx_save_csr[i];
+    }
+    return 1;
+}
+
+static int st_sha256_save_hw_context(mbedtls_sha256_context *ctx)
+{
+    uint32_t i;
+    uint32_t tickstart;
+    /* Check that there is no HASH activity on going */
+    tickstart = HAL_GetTick();
+    while ((HASH->SR & (HASH_FLAG_BUSY | HASH_FLAG_DMAS)) != 0) {
+        if ((HAL_GetTick() - tickstart) > ST_SHA256_TIMEOUT) {
+            return 0; // timeout: HASH processor is busy
+        }
+    }
+    /* allow multi-instance of HASH use: restore context for HASH HW module CR */
+    ctx->ctx_save_cr = HASH->CR;
+    ctx->ctx_save_str = HASH->STR;
+    for (i=0;i<38;i++) {
+        ctx->ctx_save_csr[i] = HASH->CSR[i];
+    }
+    return 1;
+}
+
+void mbedtls_sha256_init( mbedtls_sha256_context *ctx )
+{
+    mbedtls_zeroize( ctx, sizeof( mbedtls_sha256_context ) );
+
+    /* Enable HASH clock */
+    __HAL_RCC_HASH_CLK_ENABLE();
+}
+
+void mbedtls_sha256_free( mbedtls_sha256_context *ctx )
+{
+    if( ctx == NULL )
+        return;
+    mbedtls_zeroize( ctx, sizeof( mbedtls_sha256_context ) );
+}
+
+void mbedtls_sha256_clone( mbedtls_sha256_context *dst,
+                         const mbedtls_sha256_context *src )
+{
+    *dst = *src;
+}
+
+void mbedtls_sha256_starts( mbedtls_sha256_context *ctx, int is224 )
+{
+    /* HASH IP initialization */
+    if (HAL_HASH_DeInit(&ctx->hhash_sha256) == HAL_ERROR) {
+        // error found to be returned
+        return;
+    }
+
+    ctx->is224 = is224;
+    /* HASH Configuration */
+    ctx->hhash_sha256.Init.DataType = HASH_DATATYPE_8B;
+    if (HAL_HASH_Init(&ctx->hhash_sha256) == HAL_ERROR) {
+        // error found to be returned
+        return;
+    }
+    if (st_sha256_save_hw_context(ctx) != 1) {
+        return; // return HASH_BUSY timeout Error here
+    }
+}
+
+void mbedtls_sha256_process( mbedtls_sha256_context *ctx, const unsigned char data[ST_SHA256_BLOCK_SIZE] )
+{
+    if (st_sha256_restore_hw_context(ctx) != 1) {
+        return; // Return HASH_BUSY timout error here
+    }
+    if (ctx->is224 == 0) {
+        if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, (uint8_t *) data, ST_SHA256_BLOCK_SIZE) != 0) {
+            return; // Return error code
+        }
+    } else {
+        if (HAL_HASHEx_SHA224_Accumulate(&ctx->hhash_sha256, (uint8_t *) data, ST_SHA256_BLOCK_SIZE) != 0) {
+            return; // Return error code
+        }
+    }
+
+    if (st_sha256_save_hw_context(ctx) != 1) {
+        return; // return HASH_BUSY timeout Error here
+    }
+}
+
+void mbedtls_sha256_update( mbedtls_sha256_context *ctx, const unsigned char *input, size_t ilen )
+{
+    size_t currentlen = ilen;
+    if (st_sha256_restore_hw_context(ctx) != 1) {
+        return; // Return HASH_BUSY timout error here
+    }
+
+    // store mechanism to accumulate ST_SHA256_BLOCK_SIZE bytes (512 bits) in the HW
+    if (currentlen == 0) { // only change HW status is size if 0
+        if(ctx->hhash_sha256.Phase == HAL_HASH_PHASE_READY) {
+            /* Select the SHA256 or SHA224 mode and reset the HASH processor core, so that the HASH will be ready to compute
+             the message digest of a new message */
+            if (ctx->is224 == 0) {
+                HASH->CR |= HASH_ALGOSELECTION_SHA256 | HASH_CR_INIT;
+            } else {
+                HASH->CR |= HASH_ALGOSELECTION_SHA224 | HASH_CR_INIT;
+            }
+        }
+        ctx->hhash_sha256.Phase = HAL_HASH_PHASE_PROCESS;
+    } else if (currentlen < (ST_SHA256_BLOCK_SIZE - ctx->sbuf_len)) {
+        // only buffurize
+        memcpy(ctx->sbuf + ctx->sbuf_len, input, currentlen);
+        ctx->sbuf_len += currentlen;
+    } else {
+        // fill buffer and process it
+        memcpy(ctx->sbuf + ctx->sbuf_len, input, (ST_SHA256_BLOCK_SIZE - ctx->sbuf_len));
+        currentlen -= (ST_SHA256_BLOCK_SIZE - ctx->sbuf_len);
+        mbedtls_sha256_process(ctx, ctx->sbuf);
+        // Process every input as long as it is %64 bytes, ie 512 bits
+        size_t iter = currentlen / ST_SHA256_BLOCK_SIZE;
+        if (iter !=0) {
+            if (ctx->is224 == 0) {
+                if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, (uint8_t *)(input + ST_SHA256_BLOCK_SIZE - ctx->sbuf_len),  (iter * ST_SHA256_BLOCK_SIZE)) != 0) {
+                    return; // Return error code here
+                }
+            } else {
+                if (HAL_HASHEx_SHA224_Accumulate(&ctx->hhash_sha256, (uint8_t *)(input + ST_SHA256_BLOCK_SIZE - ctx->sbuf_len),  (iter * ST_SHA256_BLOCK_SIZE)) != 0) {
+                    return; // Return error code here
+                }
+            }
+        }
+        // sbuf is completely accumulated, now copy up to 63 remaining bytes
+        ctx->sbuf_len = currentlen % ST_SHA256_BLOCK_SIZE;
+        if (ctx->sbuf_len !=0) {
+            memcpy(ctx->sbuf, input + ilen - ctx->sbuf_len, ctx->sbuf_len);
+        }
+    }
+    if (st_sha256_save_hw_context(ctx) != 1) {
+        return; // return HASH_BUSY timeout Error here
+    }
+}
+
+void mbedtls_sha256_finish( mbedtls_sha256_context *ctx, unsigned char output[32] )
+{
+    if (st_sha256_restore_hw_context(ctx) != 1) {
+        return; // Return HASH_BUSY timout error here
+    }
+    if (ctx->sbuf_len > 0) {
+        if (ctx->is224 == 0) {
+            if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, ctx->sbuf, ctx->sbuf_len) != 0) {
+                return; // Return error code here
+            }
+        } else {
+            if (HAL_HASHEx_SHA224_Accumulate(&ctx->hhash_sha256, ctx->sbuf, ctx->sbuf_len) != 0) {
+                return; // Return error code here
+            }
+        }
+    }
+    mbedtls_zeroize(ctx->sbuf, ST_SHA256_BLOCK_SIZE);
+    ctx->sbuf_len = 0;
+    __HAL_HASH_START_DIGEST();
+
+    if (ctx->is224 == 0) {
+        if (HAL_HASHEx_SHA256_Finish(&ctx->hhash_sha256, output, 10) != 0) {
+            return; // Return error code here
+        }
+    } else {
+        if (HAL_HASHEx_SHA224_Finish(&ctx->hhash_sha256, output, 10) != 0) {
+            return; // Return error code here
+        }
+    }
+    if (st_sha256_save_hw_context(ctx) != 1) {
+        return; // return HASH_BUSY timeout Error here
+    }
+}
+
+#endif /*MBEDTLS_SHA256_ALT*/
diff --git a/features/mbedtls/targets/TARGET_STM/sha256_alt.h b/features/mbedtls/targets/TARGET_STM/sha256_alt.h
new file mode 100644
index 00000000000..b2ae7a3c293
--- /dev/null
+++ b/features/mbedtls/targets/TARGET_STM/sha256_alt.h
@@ -0,0 +1,113 @@
+/**
+ * \file sha256_alt.h
+ *
+ * \brief SHA256 hw acceleration (hash function)
+ *
+ * Copyright (c) 2017, STMicroelectronics
+ *  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 MBEDTLS_SHA256_ALT_H
+#define MBEDTLS_SHA256_ALT_H
+
+#if defined (MBEDTLS_SHA256_ALT)
+
+#include "cmsis.h"
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define ST_SHA256_BLOCK_SIZE ((size_t)  64) // HW handles 512 bits, ie 64 bytes
+#define ST_SHA256_TIMEOUT    ((uint32_t) 3)
+/**
+ * \brief          SHA-256 context structure
+ * \note     HAL_HASH_SHA256_Accumulate will accumulate 512 bits packets, unless it is the last call to the  function
+ *           A ST_SHA256_BLOCK_SIZE bytes buffer is used to save values and handle the processing
+ *           ST_SHA256_BLOCK_SIZE bytes per ST_SHA256_BLOCK_SIZE bytes
+ *           If sha256_finish is called and sbuf_len>0, the remaining bytes are accumulated prior to the call to HAL_HASH_SHA256_Finish
+ */
+typedef struct
+{
+    int is224;                  /*!< 0 => SHA-256, else SHA-224 */  
+    HASH_HandleTypeDef hhash_sha256;  
+    unsigned char sbuf[ST_SHA256_BLOCK_SIZE]; /*!< ST_SHA256_BLOCK_SIZE buffer to store values so that algorithm is called once the buffer is filled */
+    unsigned char sbuf_len; /*!< number of bytes to be processed in sbuf */
+    uint32_t ctx_save_cr;
+    uint32_t ctx_save_str;
+    uint32_t ctx_save_csr[38];
+}
+mbedtls_sha256_context;
+
+/**
+ * \brief          Initialize SHA-256 context
+ *
+ * \param ctx      SHA-256 context to be initialized
+ */
+void mbedtls_sha256_init( mbedtls_sha256_context *ctx );
+
+/**
+ * \brief          Clear SHA-256 context
+ *
+ * \param ctx      SHA-256 context to be cleared
+ */
+void mbedtls_sha256_free( mbedtls_sha256_context *ctx );
+
+/**
+ * \brief          Clone (the state of) a SHA-256 context
+ *
+ * \param dst      The destination context
+ * \param src      The context to be cloned
+ */
+void mbedtls_sha256_clone( mbedtls_sha256_context *dst,
+                           const mbedtls_sha256_context *src );
+
+/**
+ * \brief          SHA-256 context setup
+ *
+ * \param ctx      context to be initialized
+ * \param is224    0 = use SHA256, 1 = use SHA224
+ */
+void mbedtls_sha256_starts( mbedtls_sha256_context *ctx, int is224 );
+
+/**
+ * \brief          SHA-256 process buffer
+ *
+ * \param ctx      SHA-256 context
+ * \param input    buffer holding the  data
+ * \param ilen     length of the input data
+ */
+void mbedtls_sha256_update( mbedtls_sha256_context *ctx, const unsigned char *input,
+                    size_t ilen );
+
+/**
+ * \brief          SHA-256 final digest
+ *
+ * \param ctx      SHA-256 context
+ * \param output   SHA-224/256 checksum result
+ */
+void mbedtls_sha256_finish( mbedtls_sha256_context *ctx, unsigned char output[32] );
+
+/* Internal use */
+void mbedtls_sha256_process( mbedtls_sha256_context *ctx, const unsigned char data[ST_SHA256_BLOCK_SIZE] );
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MBEDTLS_SHA256_ALT */
+
+#endif /* sha256_alt.h */