Change place of ssl_tls13_check_ephemeral_key_exchange

Change-Id: Id49172f7375e2a0771ad1216fb7eead808f0db3e
Signed-off-by: XiaokangQian <xiaokang.qian@arm.com>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 6c2ba72..8332461 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -8248,7 +8248,7 @@
 
     MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, server_name_list_len );
     server_name_list_end = p + server_name_list_len;
-    while ( p < server_name_list_end )
+    while( p < server_name_list_end )
     {
         MBEDTLS_SSL_CHK_BUF_READ_PTR( p, server_name_list_end, 3 );
         hostname_len = MBEDTLS_GET_UINT16_BE( p, 1 );
@@ -8257,6 +8257,11 @@
 
         if( p[0] == MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME )
         {
+            /* sni_name is intended to be used only during the parsing of the
+             * ClientHello message (it is reset to NULL before the end of
+             * the message parsing). Thus it is ok to just point to the
+             * reception buffer and not make a copy of it.
+             */
             ssl->handshake->sni_name = p + 3;
             ssl->handshake->sni_name_len = hostname_len;
             if( ssl->conf->f_sni == NULL )
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index e4ca6aa..6527e21 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -392,7 +392,7 @@
             {
                 ssl->handshake->key_cert = key_cert;
                 MBEDTLS_SSL_DEBUG_CRT(
-                        3, "selected certificate chain, certificate",
+                        3, "selected certificate (chain)",
                         ssl->handshake->key_cert->cert );
                 return( 0 );
             }
@@ -769,10 +769,18 @@
     ssl_tls13_debug_print_client_hello_exts( ssl );
 #endif /* MBEDTLS_DEBUG_C */
 
+    return( hrr_required ? SSL_CLIENT_HELLO_HRR_REQUIRED : SSL_CLIENT_HELLO_OK );
+}
+
+/* Update the handshake state machine */
+
+static int ssl_tls13_postprocess_client_hello( mbedtls_ssl_context* ssl )
+{
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+
     /*
      * Here we only support the ephemeral or (EC)DHE key echange mode
      */
-
     if( !ssl_tls13_check_ephemeral_key_exchange( ssl ) )
     {
         MBEDTLS_SSL_DEBUG_MSG(
@@ -783,15 +791,6 @@
         return( MBEDTLS_ERR_SSL_ILLEGAL_PARAMETER );
     }
 
-    return( hrr_required ? SSL_CLIENT_HELLO_HRR_REQUIRED : SSL_CLIENT_HELLO_OK );
-}
-
-/* Update the handshake state machine */
-
-static int ssl_tls13_postprocess_client_hello( mbedtls_ssl_context* ssl )
-{
-    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
-
     /*
      * Server certificate selection
      */