tls13: client: Improve CCS handling
Call unconditionally the CCS writing function
when sending a CCS may be necessary in the
course of an handshake. Enforce in the writing
function and only in the writing function that
only one CCS is sent.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index 386a754..c6bb770 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -1379,6 +1379,12 @@
MBEDTLS_SSL_DEBUG_MSG(2, ("=> write change cipher spec"));
+ /* Only one CCS to send. */
+ if (ssl->handshake->ccs_count > 0) {
+ ret = 0;
+ goto cleanup;
+ }
+
/* Write CCS message */
MBEDTLS_SSL_PROC_CHK(ssl_tls13_write_change_cipher_spec_body(
ssl, ssl->out_msg,