diff --git a/library/ssl_tls13_keys.c b/library/ssl_tls13_keys.c
index 504d897..28090eb 100644
--- a/library/ssl_tls13_keys.c
+++ b/library/ssl_tls13_keys.c
@@ -1506,17 +1506,16 @@
 
 int mbedtls_ssl_tls13_compute_resumption_master_secret( mbedtls_ssl_context *ssl )
 {
-    int ret = 0;
-
+    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     mbedtls_md_type_t md_type;
-
-    unsigned char transcript[MBEDTLS_MD_MAX_SIZE];
+    mbedtls_ssl_handshake_params *handshake = ssl->handshake;
+    unsigned char transcript[MBEDTLS_TLS1_3_MD_MAX_SIZE];
     size_t transcript_len;
 
     MBEDTLS_SSL_DEBUG_MSG( 2,
         ( "=> mbedtls_ssl_tls13_compute_resumption_master_secret" ) );
 
-    md_type = ssl->handshake->ciphersuite_info->mac;
+    md_type = handshake->ciphersuite_info->mac;
 
     ret = mbedtls_ssl_get_handshake_transcript( ssl, md_type,
                                                 transcript, sizeof( transcript ),
@@ -1526,20 +1525,21 @@
 
     ret = mbedtls_ssl_tls13_derive_resumption_master_secret(
                               mbedtls_psa_translate_md( md_type ),
-                              ssl->handshake->tls13_master_secrets.app,
+                              handshake->tls13_master_secrets.app,
                               transcript, transcript_len,
                               &ssl->session_negotiate->app_secrets );
     if( ret != 0 )
         return( ret );
 
     /* Erase master secrets */
-    mbedtls_platform_zeroize( &ssl->handshake->tls13_master_secrets,
-                              sizeof( ssl->handshake->tls13_master_secrets ) );
+    mbedtls_platform_zeroize( &handshake->tls13_master_secrets,
+                              sizeof( handshake->tls13_master_secrets ) );
 
     MBEDTLS_SSL_DEBUG_BUF( 4, "Resumption master secret",
              ssl->session_negotiate->app_secrets.resumption_master_secret,
              mbedtls_md_get_size( mbedtls_md_info_from_type( md_type ) ) );
 
+
     MBEDTLS_SSL_DEBUG_MSG( 2,
         ( "<= mbedtls_ssl_tls13_compute_resumption_master_secret" ) );
     return( 0 );