Externals: Update mbedtls to 2.28.0

Externals/mbedtls/library/entropy.c

@@ -1,7 +1,7 @@
 /*
  *  Entropy accumulator implementation
  *
- *  Copyright (C) 2006-2016, ARM Limited, All Rights Reserved
+ *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
  *
  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -15,15 +15,9 @@
  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
- *
- *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 
-#if !defined(MBEDTLS_CONFIG_FILE)
-#include "mbedtls/config.h"
-#else
-#include MBEDTLS_CONFIG_FILE
-#endif
+#include "common.h"
 
 #if defined(MBEDTLS_ENTROPY_C)
 
@@ -36,6 +30,7 @@
 #include "mbedtls/entropy.h"
 #include "mbedtls/entropy_poll.h"
 #include "mbedtls/platform_util.h"
+#include "mbedtls/error.h"
 
 #include <string.h>
 
@@ -121,6 +116,11 @@ void mbedtls_entropy_init( mbedtls_entropy_context *ctx )
 
 void mbedtls_entropy_free( mbedtls_entropy_context *ctx )
 {
+    /* If the context was already free, don't call free() again.
+     * This is important for mutexes which don't allow double-free. */
+    if( ctx->accumulator_started == -1 )
+        return;
+
 #if defined(MBEDTLS_HAVEGE_C)
     mbedtls_havege_free( &ctx->havege_data );
 #endif
@@ -137,7 +137,7 @@ void mbedtls_entropy_free( mbedtls_entropy_context *ctx )
 #endif
     ctx->source_count = 0;
     mbedtls_platform_zeroize( ctx->source, sizeof( ctx->source ) );
-    ctx->accumulator_started = 0;
+    ctx->accumulator_started = -1;
 }
 
 int mbedtls_entropy_add_source( mbedtls_entropy_context *ctx,
@@ -236,7 +236,7 @@ cleanup:
 int mbedtls_entropy_update_manual( mbedtls_entropy_context *ctx,
                            const unsigned char *data, size_t len )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
 #if defined(MBEDTLS_THREADING_C)
     if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
@@ -258,7 +258,9 @@ int mbedtls_entropy_update_manual( mbedtls_entropy_context *ctx,
  */
 static int entropy_gather_internal( mbedtls_entropy_context *ctx )
 {
-    int ret, i, have_one_strong = 0;
+    int ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
+    int i;
+    int have_one_strong = 0;
     unsigned char buf[MBEDTLS_ENTROPY_MAX_GATHER];
     size_t olen;
 
@@ -306,7 +308,7 @@ cleanup:
  */
 int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
 {
-    int ret;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
 #if defined(MBEDTLS_THREADING_C)
     if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
@@ -325,7 +327,8 @@ int mbedtls_entropy_gather( mbedtls_entropy_context *ctx )
 
 int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
 {
-    int ret, count = 0, i, done;
+    int ret, count = 0, i, thresholds_reached;
+    size_t strong_size;
     mbedtls_entropy_context *ctx = (mbedtls_entropy_context *) data;
     unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
 
@@ -363,12 +366,17 @@ int mbedtls_entropy_func( void *data, unsigned char *output, size_t len )
         if( ( ret = entropy_gather_internal( ctx ) ) != 0 )
             goto exit;
 
-        done = 1;
+        thresholds_reached = 1;
+        strong_size = 0;
         for( i = 0; i < ctx->source_count; i++ )
+        {
             if( ctx->source[i].size < ctx->source[i].threshold )
-                done = 0;
+                thresholds_reached = 0;
+            if( ctx->source[i].strong == MBEDTLS_ENTROPY_SOURCE_STRONG )
+                strong_size += ctx->source[i].size;
+        }
     }
-    while( ! done );
+    while( ! thresholds_reached || strong_size < MBEDTLS_ENTROPY_BLOCK_SIZE );
 
     memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE );
 
@@ -463,15 +471,21 @@ int mbedtls_entropy_update_nv_seed( mbedtls_entropy_context *ctx )
 #if defined(MBEDTLS_FS_IO)
 int mbedtls_entropy_write_seed_file( mbedtls_entropy_context *ctx, const char *path )
 {
-    int ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
-    FILE *f;
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+    FILE *f = NULL;
     unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
 
-    if( ( f = fopen( path, "wb" ) ) == NULL )
-        return( MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR );
-
     if( ( ret = mbedtls_entropy_func( ctx, buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) ) != 0 )
+    {
+        ret = MBEDTLS_ERR_ENTROPY_SOURCE_FAILED;
         goto exit;
+    }
+
+    if( ( f = fopen( path, "wb" ) ) == NULL )
+    {
+        ret = MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR;
+        goto exit;
+    }
 
     if( fwrite( buf, 1, MBEDTLS_ENTROPY_BLOCK_SIZE, f ) != MBEDTLS_ENTROPY_BLOCK_SIZE )
     {
@@ -484,7 +498,9 @@ int mbedtls_entropy_write_seed_file( mbedtls_entropy_context *ctx, const char *p
 exit:
     mbedtls_platform_zeroize( buf, sizeof( buf ) );
 
-    fclose( f );
+    if( f != NULL )
+        fclose( f );
+
     return( ret );
 }