GnuTLS: Do not override priority string on shutdown for reauth

Use the previously configured priority string instead of the default
value whenever shutting down a TLS connection in preparation for
reauthentication. This fixes an issue with GnuTLS ending up using TLS
1.3 for reauthentication even when 1.3 was explicitly disabled in the
configuration. That attempt to use TLS 1.3 failed in such case due to
different key derivation between TLS 1.3 and older versions.

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/src/crypto/tls_gnutls.c b/src/crypto/tls_gnutls.c
index 7d73b4f06863038faec763aa8aad04ca97c32f35..8ce939032e4a8149887540f89f7d1a935a4e2145 100644 (file)
--- a/src/crypto/tls_gnutls.c
+++ b/src/crypto/tls_gnutls.c
@@ -62,6 +62,8 @@ struct tls_connection {
        char *suffix_match;
        char *domain_match;
        unsigned int flags;
+
+       char *prio_str;
 };
 
 
@@ -213,7 +215,9 @@ static int tls_gnutls_init_session(struct tls_global *global,
        if (ret < 0)
                goto fail;
 
-       ret = gnutls_priority_set_direct(conn->session, "NORMAL:-VERS-SSL3.0",
+       ret = gnutls_priority_set_direct(conn->session,
+                                        conn->prio_str ? conn->prio_str :
+                                        "NORMAL:-VERS-SSL3.0",
                                         &err);
        if (ret < 0) {
                wpa_printf(MSG_ERROR, "GnuTLS: Priority string failure at "
@@ -285,6 +289,7 @@ void tls_connection_deinit(void *ssl_ctx, struct tls_connection *conn)
        wpabuf_free(conn->pull_buf);
        os_free(conn->suffix_match);
        os_free(conn->domain_match);
+       os_free(conn->prio_str);
        os_free(conn);
 }
 
@@ -462,6 +467,8 @@ int tls_connection_set_params(void *tls_ctx, struct tls_connection *conn,
                                   err);
                        return -1;
                }
+               os_free(conn->prio_str);
+               conn->prio_str = os_strdup(prio);
        }
 
        if (params->openssl_ecdh_curves) {