lib-ssl-iostream: Do not attempt to load empty DH parameters

OpenSSL3 complains about empty DH parameters.

diff --git a/src/lib-ssl-iostream/iostream-openssl-context.c b/src/lib-ssl-iostream/iostream-openssl-context.c
index c0bd5bfb27f040aedfb77c1b6ab7095a85a4fd46..f0a5ad6625f0e4182436b03e8a94eef1ce89d811 100644 (file)
--- a/src/lib-ssl-iostream/iostream-openssl-context.c
+++ b/src/lib-ssl-iostream/iostream-openssl-context.c
@@ -463,7 +463,7 @@ ssl_iostream_context_set(struct ssl_iostream_context *ctx,
                        return -1;
        }
 
-       if (set->dh != NULL) {
+       if (set->dh != NULL && *set->dh != '\0') {
                if (ssl_iostream_ctx_use_dh(ctx, set, error_r) < 0)
                        return -1;
        }