tls13_record_layer_allow_ccs
tls13_record_layer_allow_ccs(ctx->rl, 1);
tls13_record_layer_allow_ccs(ctx->rl, 0);
void tls13_record_layer_allow_ccs(struct tls13_record_layer *rl, int allow);
tls13_record_layer_allow_ccs(ctx->rl, 0);
tls13_record_layer_allow_ccs(ctx->rl, 1);