Improve fix calling Accumulate function every time in finish function

Author: adustm

features/mbedtls/targets/TARGET_STM/md5_alt.c

@@ -170,17 +170,12 @@ void mbedtls_md5_finish( mbedtls_md5_context *ctx, unsigned char output[16] )
     if (st_md5_restore_hw_context(ctx) != 1) {
         return; // Return HASH_BUSY timout error here
     }
-    if (ctx->sbuf_len > 0) {
-        if (HAL_HASH_MD5_Accumulate(&ctx->hhash_md5, ctx->sbuf, ctx->sbuf_len) != 0) {
-            return; // Return error code here
-        }
-    }
-    /* The following test can happen when the input is empty, and mbedtls_md5_update has never been called */
-    if(ctx->hhash_md5.Phase == HAL_HASH_PHASE_READY) {
-        /* Select the MD5 mode and reset the HASH processor core, so that the HASH will be ready to compute
-            the message digest of a new message */
-        HASH->CR |= HASH_ALGOSELECTION_MD5 | HASH_CR_INIT;
+    /* Last accumulation for extra bytes in sbuf_len */
+    /* This allows the HW flags to be in place in case mbedtls_sha256_update has not been called yet */
+    if (HAL_HASH_MD5_Accumulate(&ctx->hhash_md5, ctx->sbuf, ctx->sbuf_len) != 0) {
+        return; // Return error code here
     }
+
     mbedtls_zeroize( ctx->sbuf, ST_MD5_BLOCK_SIZE);
     ctx->sbuf_len = 0;
     __HAL_HASH_START_DIGEST();

features/mbedtls/targets/TARGET_STM/sha1_alt.c

@@ -169,16 +169,10 @@ void mbedtls_sha1_finish( mbedtls_sha1_context *ctx, unsigned char output[20] )
         return; // Return HASH_BUSY timout error here
     }
 
-    if (ctx->sbuf_len > 0) {
-        if (HAL_HASH_SHA1_Accumulate(&ctx->hhash_sha1, ctx->sbuf, ctx->sbuf_len) != 0) {
-            return; // Return error code here
-        }
-    }
-    /* The following test can happen when the input is empty, and mbedtls_sha1_update has never been called */
-    if(ctx->hhash_sha1.Phase == HAL_HASH_PHASE_READY) {
-        /* Select the SHA1 mode and reset the HASH processor core, so that the HASH will be ready to compute
-           the message digest of a new message */
-        HASH->CR |= HASH_ALGOSELECTION_SHA1 | HASH_CR_INIT;
+    /* Last accumulation for extra bytes in sbuf_len */
+    /* This allows the HW flags to be in place in case mbedtls_sha256_update has not been called yet */
+    if (HAL_HASH_SHA1_Accumulate(&ctx->hhash_sha1, ctx->sbuf, ctx->sbuf_len) != 0) {
+        return; // Return error code here
     }
     mbedtls_zeroize(ctx->sbuf, ST_SHA1_BLOCK_SIZE);
     ctx->sbuf_len = 0;

features/mbedtls/targets/TARGET_STM/sha256_alt.c

@@ -187,29 +187,18 @@ 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
-            }
+    /* Last accumulation for extra bytes in sbuf_len */
+    /* This allows the HW flags to be in place in case mbedtls_sha256_update has not been called yet */
+    if (ctx->is224 == 0) {
+        if (HAL_HASHEx_SHA256_Accumulate(&ctx->hhash_sha256, ctx->sbuf, ctx->sbuf_len) != 0) {
+            return; // Return error code here
         }
-    }
-    /* The following test can happen when the input is empty, and mbedtls_sha256_update has never been called */
-    if(ctx->hhash_sha256.Phase == HAL_HASH_PHASE_READY) {
-        if (ctx->is224 == 0) {
-            /* Select the SHA256 mode and reset the HASH processor core, so that the HASH will be ready to compute
-           the message digest of a new message */
-            HASH->CR |= HASH_ALGOSELECTION_SHA256 | HASH_CR_INIT;
-        } else {
-            /* Select the SHA224 mode and reset the HASH processor core, so that the HASH will be ready to compute
-           the message digest of a new message */
-            HASH->CR |= HASH_ALGOSELECTION_SHA224 | HASH_CR_INIT;
+    } 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();