Merge pull request #8173 from gilles-peskine-arm/config-boolean-optio…

…ns-wrong-section-202309-2.28 Backport 2.28: Fix boolean options in the wrong section
Mbed-TLS · Sep 11, 2023 · 198fbc2 · 198fbc2
2 parents 06c466d + 3a11771
commit 198fbc2
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diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
@@ -265,6 +265,45 @@
 //#define MBEDTLS_PLATFORM_NV_SEED_ALT
 //#define MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT
 
+/**
+ * Uncomment the macro to let Mbed TLS use your alternate implementation of
+ * mbedtls_platform_gmtime_r(). This replaces the default implementation in
+ * platform_util.c.
+ *
+ * gmtime() is not a thread-safe function as defined in the C standard. The
+ * library will try to use safer implementations of this function, such as
+ * gmtime_r() when available. However, if Mbed TLS cannot identify the target
+ * system, the implementation of mbedtls_platform_gmtime_r() will default to
+ * using the standard gmtime(). In this case, calls from the library to
+ * gmtime() will be guarded by the global mutex mbedtls_threading_gmtime_mutex
+ * if MBEDTLS_THREADING_C is enabled. We recommend that calls from outside the
+ * library are also guarded with this mutex to avoid race conditions. However,
+ * if the macro MBEDTLS_PLATFORM_GMTIME_R_ALT is defined, Mbed TLS will
+ * unconditionally use the implementation for mbedtls_platform_gmtime_r()
+ * supplied at compile time.
+ */
+//#define MBEDTLS_PLATFORM_GMTIME_R_ALT
+
+/**
+ * Uncomment the macro to let mbed TLS use your alternate implementation of
+ * mbedtls_platform_zeroize(). This replaces the default implementation in
+ * platform_util.c.
+ *
+ * mbedtls_platform_zeroize() is a widely used function across the library to
+ * zero a block of memory. The implementation is expected to be secure in the
+ * sense that it has been written to prevent the compiler from removing calls
+ * to mbedtls_platform_zeroize() as part of redundant code elimination
+ * optimizations. However, it is difficult to guarantee that calls to
+ * mbedtls_platform_zeroize() will not be optimized by the compiler as older
+ * versions of the C language standards do not provide a secure implementation
+ * of memset(). Therefore, MBEDTLS_PLATFORM_ZEROIZE_ALT enables users to
+ * configure their own implementation of mbedtls_platform_zeroize(), for
+ * example by using directives specific to their compiler, features from newer
+ * C standards (e.g using memset_s() in C11) or calling a secure memset() from
+ * their system (e.g explicit_bzero() in BSD).
+ */
+//#define MBEDTLS_PLATFORM_ZEROIZE_ALT
+
 /**
  * \def MBEDTLS_DEPRECATED_WARNING
  *
@@ -818,6 +857,15 @@
  */
 #define MBEDTLS_REMOVE_3DES_CIPHERSUITES
 
+/**
+ * Enable the verified implementations of ECDH primitives from Project Everest
+ * (currently only Curve25519). This feature changes the layout of ECDH
+ * contexts and therefore is a compatibility break for applications that access
+ * fields of a mbedtls_ecdh_context structure directly. See also
+ * MBEDTLS_ECDH_LEGACY_CONTEXT in include/mbedtls/ecdh.h.
+ */
+//#define MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
+
 /**
  * \def MBEDTLS_ECP_DP_SECP192R1_ENABLED
  *
@@ -2117,6 +2165,23 @@
  */
 //#define MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH
 
+/**
+ * Allow SHA-1 in the default TLS configuration for TLS 1.2 handshake
+ * signature and ciphersuite selection. Without this build-time option, SHA-1
+ * support must be activated explicitly through mbedtls_ssl_conf_sig_hashes.
+ * The use of SHA-1 in TLS <= 1.1 and in HMAC-SHA-1 is always allowed by
+ * default. At the time of writing, there is no practical attack on the use
+ * of SHA-1 in handshake signatures, hence this option is turned on by default
+ * to preserve compatibility with existing peers, but the general
+ * warning applies nonetheless:
+ *
+ * \warning   SHA-1 is considered a weak message digest and its use constitutes
+ *            a security risk. If possible, we recommend avoiding dependencies
+ *            on it, and considering stronger message digests instead.
+ *
+ */
+//#define MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE
+
 /**
  * \def MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN
  *
@@ -4141,71 +4206,6 @@
 //#define MBEDTLS_X509_MAX_INTERMEDIATE_CA   8   /**< Maximum number of intermediate CAs in a verification chain. */
 //#define MBEDTLS_X509_MAX_FILE_PATH_LEN     512 /**< Maximum length of a path/filename string in bytes including the null terminator character ('\0'). */
 
-/**
- * Allow SHA-1 in the default TLS configuration for TLS 1.2 handshake
- * signature and ciphersuite selection. Without this build-time option, SHA-1
- * support must be activated explicitly through mbedtls_ssl_conf_sig_hashes.
- * The use of SHA-1 in TLS <= 1.1 and in HMAC-SHA-1 is always allowed by
- * default. At the time of writing, there is no practical attack on the use
- * of SHA-1 in handshake signatures, hence this option is turned on by default
- * to preserve compatibility with existing peers, but the general
- * warning applies nonetheless:
- *
- * \warning   SHA-1 is considered a weak message digest and its use constitutes
- *            a security risk. If possible, we recommend avoiding dependencies
- *            on it, and considering stronger message digests instead.
- *
- */
-//#define MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE
-
-/**
- * Uncomment the macro to let mbed TLS use your alternate implementation of
- * mbedtls_platform_zeroize(). This replaces the default implementation in
- * platform_util.c.
- *
- * mbedtls_platform_zeroize() is a widely used function across the library to
- * zero a block of memory. The implementation is expected to be secure in the
- * sense that it has been written to prevent the compiler from removing calls
- * to mbedtls_platform_zeroize() as part of redundant code elimination
- * optimizations. However, it is difficult to guarantee that calls to
- * mbedtls_platform_zeroize() will not be optimized by the compiler as older
- * versions of the C language standards do not provide a secure implementation
- * of memset(). Therefore, MBEDTLS_PLATFORM_ZEROIZE_ALT enables users to
- * configure their own implementation of mbedtls_platform_zeroize(), for
- * example by using directives specific to their compiler, features from newer
- * C standards (e.g using memset_s() in C11) or calling a secure memset() from
- * their system (e.g explicit_bzero() in BSD).
- */
-//#define MBEDTLS_PLATFORM_ZEROIZE_ALT
-
-/**
- * Uncomment the macro to let Mbed TLS use your alternate implementation of
- * mbedtls_platform_gmtime_r(). This replaces the default implementation in
- * platform_util.c.
- *
- * gmtime() is not a thread-safe function as defined in the C standard. The
- * library will try to use safer implementations of this function, such as
- * gmtime_r() when available. However, if Mbed TLS cannot identify the target
- * system, the implementation of mbedtls_platform_gmtime_r() will default to
- * using the standard gmtime(). In this case, calls from the library to
- * gmtime() will be guarded by the global mutex mbedtls_threading_gmtime_mutex
- * if MBEDTLS_THREADING_C is enabled. We recommend that calls from outside the
- * library are also guarded with this mutex to avoid race conditions. However,
- * if the macro MBEDTLS_PLATFORM_GMTIME_R_ALT is defined, Mbed TLS will
- * unconditionally use the implementation for mbedtls_platform_gmtime_r()
- * supplied at compile time.
- */
-//#define MBEDTLS_PLATFORM_GMTIME_R_ALT
-
-/**
- * Enable the verified implementations of ECDH primitives from Project Everest
- * (currently only Curve25519). This feature changes the layout of ECDH
- * contexts and therefore is a compatibility break for applications that access
- * fields of a mbedtls_ecdh_context structure directly. See also
- * MBEDTLS_ECDH_LEGACY_CONTEXT in include/mbedtls/ecdh.h.
- */
-//#define MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
-
 /** \} name SECTION: Module configuration options */
 
 /* Target and application specific configurations

diff --git a/library/version_features.c b/library/version_features.c
@@ -75,6 +75,12 @@ static const char * const features[] = {
 #if defined(MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT)
     "MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT",
 #endif /* MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT */
+#if defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
+    "MBEDTLS_PLATFORM_GMTIME_R_ALT",
+#endif /* MBEDTLS_PLATFORM_GMTIME_R_ALT */
+#if defined(MBEDTLS_PLATFORM_ZEROIZE_ALT)
+    "MBEDTLS_PLATFORM_ZEROIZE_ALT",
+#endif /* MBEDTLS_PLATFORM_ZEROIZE_ALT */
 #if defined(MBEDTLS_DEPRECATED_WARNING)
     "MBEDTLS_DEPRECATED_WARNING",
 #endif /* MBEDTLS_DEPRECATED_WARNING */
@@ -312,6 +318,9 @@ static const char * const features[] = {
 #if defined(MBEDTLS_REMOVE_3DES_CIPHERSUITES)
     "MBEDTLS_REMOVE_3DES_CIPHERSUITES",
 #endif /* MBEDTLS_REMOVE_3DES_CIPHERSUITES */
+#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED)
+    "MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED",
+#endif /* MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED */
 #if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
     "MBEDTLS_ECP_DP_SECP192R1_ENABLED",
 #endif /* MBEDTLS_ECP_DP_SECP192R1_ENABLED */
@@ -576,6 +585,9 @@ static const char * const features[] = {
 #if defined(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH)
     "MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH",
 #endif /* MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH */
+#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE)
+    "MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE",
+#endif /* MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE */
 #if defined(MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN)
     "MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN",
 #endif /* MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN */

diff --git a/programs/test/query_config.c b/programs/test/query_config.c
@@ -260,6 +260,22 @@ int query_config(const char *config)
     }
 #endif /* MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT */
 
+#if defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
+    if( strcmp( "MBEDTLS_PLATFORM_GMTIME_R_ALT", config ) == 0 )
+    {
+        MACRO_EXPANSION_TO_STR( MBEDTLS_PLATFORM_GMTIME_R_ALT );
+        return( 0 );
+    }
+#endif /* MBEDTLS_PLATFORM_GMTIME_R_ALT */
+
+#if defined(MBEDTLS_PLATFORM_ZEROIZE_ALT)
+    if( strcmp( "MBEDTLS_PLATFORM_ZEROIZE_ALT", config ) == 0 )
+    {
+        MACRO_EXPANSION_TO_STR( MBEDTLS_PLATFORM_ZEROIZE_ALT );
+        return( 0 );
+    }
+#endif /* MBEDTLS_PLATFORM_ZEROIZE_ALT */
+
 #if defined(MBEDTLS_DEPRECATED_WARNING)
     if( strcmp( "MBEDTLS_DEPRECATED_WARNING", config ) == 0 )
     {
@@ -892,6 +908,14 @@ int query_config(const char *config)
     }
 #endif /* MBEDTLS_REMOVE_3DES_CIPHERSUITES */
 
+#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED)
+    if( strcmp( "MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED", config ) == 0 )
+    {
+        MACRO_EXPANSION_TO_STR( MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED );
+        return( 0 );
+    }
+#endif /* MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED */
+
 #if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
     if( strcmp( "MBEDTLS_ECP_DP_SECP192R1_ENABLED", config ) == 0 )
     {
@@ -1596,6 +1620,14 @@ int query_config(const char *config)
     }
 #endif /* MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH */
 
+#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE)
+    if( strcmp( "MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE", config ) == 0 )
+    {
+        MACRO_EXPANSION_TO_STR( MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE );
+        return( 0 );
+    }
+#endif /* MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE */
+
 #if defined(MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN)
     if( strcmp( "MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN", config ) == 0 )
     {
@@ -2844,38 +2876,6 @@ int query_config(const char *config)
     }
 #endif /* MBEDTLS_X509_MAX_FILE_PATH_LEN */
 
-#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE)
-    if( strcmp( "MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE", config ) == 0 )
-    {
-        MACRO_EXPANSION_TO_STR( MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE );
-        return( 0 );
-    }
-#endif /* MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE */
-
-#if defined(MBEDTLS_PLATFORM_ZEROIZE_ALT)
-    if( strcmp( "MBEDTLS_PLATFORM_ZEROIZE_ALT", config ) == 0 )
-    {
-        MACRO_EXPANSION_TO_STR( MBEDTLS_PLATFORM_ZEROIZE_ALT );
-        return( 0 );
-    }
-#endif /* MBEDTLS_PLATFORM_ZEROIZE_ALT */
-
-#if defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
-    if( strcmp( "MBEDTLS_PLATFORM_GMTIME_R_ALT", config ) == 0 )
-    {
-        MACRO_EXPANSION_TO_STR( MBEDTLS_PLATFORM_GMTIME_R_ALT );
-        return( 0 );
-    }
-#endif /* MBEDTLS_PLATFORM_GMTIME_R_ALT */
-
-#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED)
-    if( strcmp( "MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED", config ) == 0 )
-    {
-        MACRO_EXPANSION_TO_STR( MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED );
-        return( 0 );
-    }
-#endif /* MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED */
-
  /* If the symbol is not found, return an error */
     return 1;
 }
@@ -2946,6 +2946,14 @@ void list_config(void)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT);
 #endif /* MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT */
 
+#if defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
+    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_PLATFORM_GMTIME_R_ALT);
+#endif /* MBEDTLS_PLATFORM_GMTIME_R_ALT */
+
+#if defined(MBEDTLS_PLATFORM_ZEROIZE_ALT)
+    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_PLATFORM_ZEROIZE_ALT);
+#endif /* MBEDTLS_PLATFORM_ZEROIZE_ALT */
+
 #if defined(MBEDTLS_DEPRECATED_WARNING)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_DEPRECATED_WARNING);
 #endif /* MBEDTLS_DEPRECATED_WARNING */
@@ -3262,6 +3270,10 @@ void list_config(void)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_REMOVE_3DES_CIPHERSUITES);
 #endif /* MBEDTLS_REMOVE_3DES_CIPHERSUITES */
 
+#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED)
+    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED);
+#endif /* MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED */
+
 #if defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_ECP_DP_SECP192R1_ENABLED);
 #endif /* MBEDTLS_ECP_DP_SECP192R1_ENABLED */
@@ -3614,6 +3626,10 @@ void list_config(void)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH);
 #endif /* MBEDTLS_SSL_VARIABLE_BUFFER_LENGTH */
 
+#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE)
+    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE);
+#endif /* MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE */
+
 #if defined(MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN);
 #endif /* MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN */
@@ -4238,22 +4254,6 @@ void list_config(void)
     OUTPUT_MACRO_NAME_VALUE(MBEDTLS_X509_MAX_FILE_PATH_LEN);
 #endif /* MBEDTLS_X509_MAX_FILE_PATH_LEN */
 
-#if defined(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE)
-    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE);
-#endif /* MBEDTLS_TLS_DEFAULT_ALLOW_SHA1_IN_KEY_EXCHANGE */
-
-#if defined(MBEDTLS_PLATFORM_ZEROIZE_ALT)
-    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_PLATFORM_ZEROIZE_ALT);
-#endif /* MBEDTLS_PLATFORM_ZEROIZE_ALT */
-
-#if defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
-    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_PLATFORM_GMTIME_R_ALT);
-#endif /* MBEDTLS_PLATFORM_GMTIME_R_ALT */
-
-#if defined(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED)
-    OUTPUT_MACRO_NAME_VALUE(MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED);
-#endif /* MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED */
-
 
 }
 #if defined(_MSC_VER)

diff --git a/scripts/config.py b/scripts/config.py
@@ -225,7 +225,11 @@ def is_seamless_alt(name):
     Exclude alternative implementations of library functions since they require
     an implementation of the relevant functions and an xxx_alt.h header.
     """
-    if name == 'MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT':
+    if name in (
+            'MBEDTLS_PLATFORM_GMTIME_R_ALT',
+            'MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT',
+            'MBEDTLS_PLATFORM_ZEROIZE_ALT',
+    ):
         # Similar to non-platform xxx_ALT, requires platform_alt.h
         return False
     return name.startswith('MBEDTLS_PLATFORM_')