Enable Fortinet DPD even if server doesn't say that reconnect-after-drop is allowed

Even if we can't automatically reconnect, disabling DPD doesn't seem like a
good idea.  This will just recapitulate the poor behavior of official
Fortinet clients, which don't provide useful signals about dropped
connection.

Instead, let's just tell users explicitly that reconnect probably won't work
in the logging messages.

Signed-off-by: Daniel Lenski <dlenski@gmail.com>

diff --git a/fortinet.c b/fortinet.c
index 6fbbaa86828eec78f68397b03051ca61a12362d9..c9e1a420ed94a9cd034b9fb537eeb5cc938d299e 100644 (file)
--- a/fortinet.c
+++ b/fortinet.c
@@ -298,7 +298,7 @@ static int parse_fortinet_xml_config(struct openconnect_info *vpninfo, char *buf
        xmlDocPtr xml_doc;
        int ret = 0, n_dns = 0, default_route = 1;
        char *s = NULL, *s2 = NULL;
-       int heartbeat_interval = -1, reconnect_after_drop = -1;
+       int reconnect_after_drop = -1;
        struct oc_text_buf *domains = NULL;
 
        if (!buf || !len)
@@ -338,9 +338,11 @@ static int parse_fortinet_xml_config(struct openconnect_info *vpninfo, char *buf
                else if (xmlnode_is_named(xml_node, "idle-timeout") && !xmlnode_get_prop(xml_node, "val", &s)) {
                        int sec = vpninfo->idle_timeout = atoi(s);
                        vpn_progress(vpninfo, PRG_INFO, _("Idle timeout is %d minutes.\n"), sec/60);
-               } else if (xmlnode_is_named(xml_node, "dtls-config") && !xmlnode_get_prop(xml_node, "heartbeat-interval", &s))
-                       heartbeat_interval = atoi(s);
-               else if (xmlnode_is_named(xml_node, "auth-ses")) {
+               } else if (xmlnode_is_named(xml_node, "dtls-config") && !xmlnode_get_prop(xml_node, "heartbeat-interval", &s)) {
+                       int sec = atoi(s);
+                       if (sec && (!vpninfo->dtls_times.dpd || sec < vpninfo->dtls_times.dpd))
+                               vpninfo->dtls_times.dpd = vpninfo->ssl_times.dpd = sec;
+               } else if (xmlnode_is_named(xml_node, "auth-ses")) {
                        /* These settings were apparently added in v6.2.1 of the Fortigate server,
                         * (see https://docs.fortinet.com/document/fortigate/6.2.1/cli-reference/281620/vpn-ssl-settings)
                         * and seem to control the possibility of reconnecting after a dropped connection.
@@ -358,15 +360,12 @@ static int parse_fortinet_xml_config(struct openconnect_info *vpninfo, char *buf
                                                     _("Server reports that reconnect-after-drop is allowed within %d seconds, %s\n"),
                                                     dropped_session_cleanup,
                                                     check_ip_src ? _("but only from the same source IP address") : _("even if source IP address changes"));
-                               } else if (reconnect_after_drop == 0) {
+                               } else if (reconnect_after_drop == 0)
                                        vpn_progress(vpninfo, PRG_ERR,
-                                                    _("Server reports that reconnect-after-drop is not allowed.\n"));
-                               }
-                       } else
-                               vpn_progress(vpninfo, PRG_ERR,
-                                            _("Contents of <auth-ses> tag are unexpected.\n"));
-                       vpn_progress(vpninfo, PRG_ERR,
-                                    _("Please report whether Fortinet reconnect-after-drop works to <openconnect-devel@lists.infradead.org>\n"));
+                                                    _("Server reports that reconnect-after-drop is not allowed. OpenConnect will not\n"
+                                                      "be able to reconnect if dead peer is detected. If reconnection DOES work,\n"
+                                                      "please report to <openconnect-devel@lists.infradead.org>\n"));
+                       }
                } else if (xmlnode_is_named(xml_node, "fos")) {
                        char platform[80], *p = platform, *e = platform + 80;
                        if (!xmlnode_get_prop(xml_node, "platform", &s)) {
@@ -507,18 +506,11 @@ static int parse_fortinet_xml_config(struct openconnect_info *vpninfo, char *buf
                }
        }
 
-       if (heartbeat_interval > 0) {
-               /* Ignore server's heartbeat/DPD interval unless server actually allows
-                * reconnect-after-drop (without reauthentication).
-                */
-               if (reconnect_after_drop > 0) {
-                       if (!vpninfo->dtls_times.dpd || heartbeat_interval < vpninfo->dtls_times.dpd)
-                               vpninfo->dtls_times.dpd = vpninfo->ssl_times.dpd = heartbeat_interval;
-               } else
-                       vpn_progress(vpninfo, PRG_ERR,
-                                    _("Ignoring server's heartbeat/DPD interval of %d seconds, because reconnect-after-drop is not allowed.\n"),
-                                    heartbeat_interval);
-       }
+       if (reconnect_after_drop == -1)
+               vpn_progress(vpninfo, PRG_ERR,
+                            _("Server did not send <auth-ses tun-connect-without-reauth=\"0/1\"/>. OpenConnect will\n"
+                              "probably not be able to reconnect if dead peer is detected. If reconnection DOES,\n"
+                              "work please report to <openconnect-devel@lists.infradead.org>\n"));
 
        if (default_route && new_ip_info.addr)
                new_ip_info.netmask = add_option_dup(&new_opts, "full-netmask", "0.0.0.0", -1);
@@ -600,7 +592,7 @@ static int fortinet_configure(struct openconnect_info *vpninfo)
                        int ret2 = do_https_request(vpninfo, "GET", NULL, NULL, &res_buf, NULL, 0);
                        if (ret2 == 0)
                                vpn_progress(vpninfo, PRG_ERR,
-                                            _("Ancient Fortinet server (<v5?) only support ancient HTML config, which is not implemented by OpenConnect.\n"));
+                                            _("Ancient Fortinet server (<v5?) only supports ancient HTML config, which is not implemented by OpenConnect.\n"));
                        else
                                vpn_progress(vpninfo, PRG_ERR,
                                             _("Fortinet server is rejecting request for connection options. This\n"