enforce single source for SSL buffer size

nodemcu · Feb 2, 2018 · fb96406 · fb96406
1 parent 2cbce29
commit fb96406
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Showing 2 changed files with 19 additions and 1 deletion.
diff --git a/app/include/user_mbedtls.h b/app/include/user_mbedtls.h
@@ -1,5 +1,7 @@
 #include "c_types.h"
 
+#include "user_config.h"
+
 #undef MBEDTLS_HAVE_ASM
 #undef MBEDTLS_HAVE_SSE2
 
@@ -288,7 +290,19 @@
 //#define MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO  mbedtls_platform_std_nv_seed_write /**< Default nv_seed_write function to use, can be undefined */
 //#define MBEDTLS_SSL_CACHE_DEFAULT_TIMEOUT       86400 /**< 1 day  */
 //#define MBEDTLS_SSL_CACHE_DEFAULT_MAX_ENTRIES      50 /**< Maximum entries in cache */
-#define MBEDTLS_SSL_MAX_CONTENT_LEN             4096 /**< Maxium fragment length in bytes, determines the size of each of the two internal I/O buffers */
+
+#if 0
+// dynamic buffer sizing with espconn_secure_set_size()
+extern unsigned int max_content_len;
+#define MBEDTLS_SSL_MAX_CONTENT_LEN             max_content_len;
+#else
+// the current mbedtls integration doesn't allow to set the buffer size dynamically:
+//   MBEDTLS_SSL_MAX_FRAGMENT_LENGTH feature and dynamic sizing are mutually exclusive
+//   due to non-constant initializer element in app/mbedtls/library/ssl_tls.c:150 
+// the buffer size is hardcoded here and value is taken from SSL_BUFFER_SIZE (user_config.h)
+#define MBEDTLS_SSL_MAX_CONTENT_LEN             SSL_BUFFER_SIZE /**< Maxium fragment length in bytes, determines the size of each of the two internal I/O buffers */
+#endif
+
 //#define MBEDTLS_SSL_DEFAULT_TICKET_LIFETIME     86400 /**< Lifetime of session tickets (if enabled) */
 //#define MBEDTLS_PSK_MAX_LEN               32 /**< Max size of TLS pre-shared keys, in bytes (default 256 bits) */
 //#define MBEDTLS_SSL_COOKIE_TIMEOUT        60 /**< Default expiration delay of DTLS cookies, in seconds if HAVE_TIME, or in number of cookies issued */

diff --git a/app/user/user_main.c b/app/user/user_main.c
@@ -150,9 +150,13 @@ void nodemcu_init(void)
         return;
     }
 
+#if 0
+// espconn_secure_set_size() is not effective
+// see comments for MBEDTLS_SSL_MAX_CONTENT_LEN in user_mbedtls.h
 #if defined ( CLIENT_SSL_ENABLE ) && defined ( SSL_BUFFER_SIZE )
     espconn_secure_set_size(ESPCONN_CLIENT, SSL_BUFFER_SIZE);
 #endif
+#endif
 
 #ifdef BUILD_SPIFFS
     if (!vfs_mount("/FLASH", 0)) {