diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index d183078..976c38f 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -3677,7 +3677,11 @@
 #endif
     hash_len = 12;
 
-    ssl->handshake->calc_finished(ssl, buf, ssl->conf->endpoint ^ 1);
+    ret = ssl->handshake->calc_finished(ssl, buf, ssl->conf->endpoint ^ 1);
+    if (ret != 0) {
+        MBEDTLS_SSL_DEBUG_RET(1, "calc_finished", ret);
+        goto exit;
+    }
 
     if ((ret = mbedtls_ssl_read_record(ssl, 1)) != 0) {
         MBEDTLS_SSL_DEBUG_RET(1, "mbedtls_ssl_read_record", ret);