dhcp6: fix to send up to 5 release retransmissions

man/wicked-config.5.in

@@ -575,6 +575,10 @@ lease time to one hour:
 .IP
 .B "  <lease-time>3600</lease-time>
 .PP
+.TP
+.B release-retransmits
+Specifies the number of lease release retransmissions in the range 1..5.
+Default is to send up to 5 (REL_MAX_RC) retransmissions.
 
 .TP
 .B ignore-server

src/appconfig.h

@@ -135,6 +135,7 @@ typedef struct ni_config_dhcp6 {
 
 	unsigned int		allow_update;
 	unsigned int		lease_time;
+	unsigned int		release_nretries;
 
 	ni_string_array_t 	user_class_data;
 	unsigned int		vendor_class_en;

src/config.c

@@ -80,6 +80,7 @@ ni_config_new()
 	conf->addrconf.auto4.allow_update   = ni_config_addrconf_update_auto4();
 	conf->addrconf.auto6.allow_update   = ni_config_addrconf_update_auto6();
 	conf->addrconf.dhcp4.routes_opts = -1U;
+	conf->addrconf.dhcp6.release_nretries = -1U;
 
 	ni_config_fslocation_init(&conf->piddir,   WICKED_PIDDIR,   0755);
 	ni_config_fslocation_init(&conf->statedir, WICKED_STATEDIR, 0755);
@@ -1071,6 +1072,9 @@ ni_config_parse_addrconf_dhcp6_nodes(ni_config_dhcp6_t *dhcp6, xml_node_t *node)
 		if (!strcmp(child->name, "lease-time") && child->cdata) {
 			dhcp6->lease_time = strtoul(child->cdata, NULL, 0);
 		} else
+		if (!strcmp(child->name, "release-retransmits") && child->cdata) {
+			dhcp6->release_nretries = strtoul(child->cdata, NULL, 0);
+		} else
 		if (!strcmp(child->name, "ignore-server")
 		 && (attrval = xml_node_get_attr(child, "ip")) != NULL) {
 			ni_string_array_append(&dhcp6->ignore_servers, attrval);

src/dhcp6/device.c

@@ -774,22 +774,25 @@ ni_dhcp6_device_retransmit_advance(ni_dhcp6_device_t *dev)
 
 		return TRUE;
 	}
-	ni_debug_dhcp("Retransmissions are disabled");
+	ni_debug_dhcp("%s: retransmission limit reached", dev->ifname);
 	return FALSE;
 }
 
 int
 ni_dhcp6_device_retransmit(ni_dhcp6_device_t *dev)
 {
+	int rv;
+
 	if (!ni_dhcp6_device_retransmit_advance(dev)) {
+		rv = ni_dhcp6_fsm_retransmit_end(dev);
 		ni_dhcp6_device_retransmit_disarm(dev);
-		return -1;
+		return rv;
 	}
 
-	if (ni_dhcp6_fsm_retransmit(dev) < 0)
-		return -1;
+	if ((rv = ni_dhcp6_fsm_retransmit(dev)) < 0)
+		return rv;
 
-	ni_debug_dhcp("Retransmitted, next deadline at %s",
+	ni_debug_dhcp("%s: retransmitted, next deadline at %s", dev->ifname,
 			ni_dhcp6_print_timeval(&dev->retrans.deadline));
 	return 0;
 }
@@ -1049,13 +1052,12 @@ ni_dhcp6_start_release(void *user_data, const ni_timer_t *timer)
 		return;
 	dev->fsm.timer = NULL;
 
-	/* We just send out a singe RELEASE without waiting for the
-	 * server's reply. We just keep our fingers crossed that it's
-	 * getting out. If it doesn't, it's rather likely the network
-	 * is hosed anyway, so there's little point in delaying. */
-	ni_dhcp6_fsm_release(dev);
-	ni_dhcp6_device_stop(dev);
 	ni_dhcp6_device_set_request(dev, NULL);
+	if (ni_dhcp6_fsm_release(dev) > 0)
+		return;
+
+	ni_dhcp6_device_drop_lease(dev);
+	ni_dhcp6_device_stop(dev);
 }
 
 int
@@ -1069,8 +1071,9 @@ ni_dhcp6_release(ni_dhcp6_device_t *dev, const ni_uuid_t *req_uuid)
 			rel_uuid ? " using UUID " : "", rel_uuid ? rel_uuid : "");
 		ni_string_free(&rel_uuid);
 
-		ni_dhcp6_device_stop(dev);
 		ni_dhcp6_device_set_request(dev, NULL);
+		ni_dhcp6_device_drop_lease(dev);
+		ni_dhcp6_device_stop(dev);
 		return -NI_ERROR_ADDRCONF_NO_LEASE;
 	}
 
@@ -1354,6 +1357,14 @@ ni_dhcp6_config_max_lease_time(void)
 	return ni_global.config->addrconf.dhcp6.lease_time;
 }
 
+unsigned int
+ni_dhcp6_config_release_nretries(const char *ifname)
+{
+	const ni_config_dhcp6_t *conf = ni_config_dhcp6_find_device(ifname);
+	/* >0: RFC 3315 Section 18.1.6, SHOULD retransmit one or more times */
+	return conf && conf->release_nretries ? conf->release_nretries : -1U;
+}
+
 static void
 ni_dhcp6_config_set_request_options(const char *ifname, ni_uint_array_t *cfg, const ni_string_array_t *req)
 {

src/dhcp6/device.h

@@ -55,5 +55,6 @@ extern int		ni_dhcp6_config_ignore_server(struct in6_addr);
 extern ni_bool_t	ni_dhcp6_config_have_server_preference(void);
 extern ni_bool_t	ni_dhcp6_config_server_preference(const struct in6_addr *, const ni_opaque_t *, int *);
 extern unsigned int	ni_dhcp6_config_max_lease_time(void);
+extern unsigned int	ni_dhcp6_config_release_nretries(const char *);
 
 #endif /* __WICKED_DHCP6_DEVICE_H__ */

src/dhcp6/fsm.c

@@ -203,6 +203,19 @@ ni_dhcp6_fsm_retransmit(ni_dhcp6_device_t *dev)
 	}
 }
 
+int
+ni_dhcp6_fsm_retransmit_end(ni_dhcp6_device_t *dev)
+{
+	switch (dev->fsm.state) {
+	case NI_DHCP6_STATE_RELEASING:
+		ni_dhcp6_fsm_commit_lease(dev, NULL);
+		ni_dhcp6_device_stop(dev);
+		return 0;
+	default:
+		return -1;
+	}
+}
+
 void
 ni_dhcp6_fsm_set_timeout_msec(ni_dhcp6_device_t *dev, unsigned long msec)
 {
@@ -442,6 +455,7 @@ ni_dhcp6_fsm_timeout(ni_dhcp6_device_t *dev)
 		break;
 
 	case NI_DHCP6_STATE_RELEASING:
+		ni_dhcp6_fsm_commit_lease(dev, NULL);
 		ni_dhcp6_device_drop_lease(dev);
 		ni_dhcp6_device_stop(dev);
 		break;
@@ -1586,7 +1600,7 @@ __ni_dhcp6_fsm_release(ni_dhcp6_device_t *dev, unsigned int nretries)
 			return -1;
 
 		dev->fsm.state = NI_DHCP6_STATE_RELEASING;
-		if (nretries != -1U)
+		if (nretries < (unsigned int)dev->retrans.params.nretries)
 			dev->retrans.params.nretries = nretries;
 		rv = ni_dhcp6_device_transmit_init(dev);
 	} else {
@@ -1603,20 +1617,19 @@ __ni_dhcp6_fsm_release(ni_dhcp6_device_t *dev, unsigned int nretries)
 int
 ni_dhcp6_fsm_release(ni_dhcp6_device_t *dev)
 {
-	if (dev->config == NULL) {
-		ni_debug_dhcp("%s: not configured, dropping lease", dev->ifname);
-		return ni_dhcp6_fsm_commit_lease(dev, NULL);
-	}
+	unsigned int nretries;
 
 	/* When all IA's are expired, just commit a release */
 	if (ni_dhcp6_lease_with_active_address(dev->lease)) {
-		if (dev->config->release_lease)
-			__ni_dhcp6_fsm_release(dev, 0);
-		return ni_dhcp6_fsm_commit_lease(dev, NULL);
+		if (dev->config && dev->config->release_lease) {
+			nretries = ni_dhcp6_config_release_nretries(dev->ifname);
+			if (__ni_dhcp6_fsm_release(dev, nretries) == 0)
+				return 1;
+		}
 	}
 
 	if (dev->lease)
-		ni_dhcp6_fsm_commit_lease(dev, NULL);
+		ni_dhcp6_send_event(NI_DHCP6_EVENT_RELEASED, dev, dev->lease);
 	return 0;
 }
 

src/dhcp6/fsm.h

@@ -59,6 +59,7 @@ extern void			ni_dhcp6_fsm_reset(ni_dhcp6_device_t *dev);
 extern int			ni_dhcp6_fsm_release(ni_dhcp6_device_t *dev);
 
 extern int			ni_dhcp6_fsm_retransmit(ni_dhcp6_device_t *dev);
+extern int			ni_dhcp6_fsm_retransmit_end(ni_dhcp6_device_t *dev);
 
 extern void			ni_dhcp6_fsm_address_event(ni_dhcp6_device_t *, ni_netdev_t *,
 								ni_event_t, const ni_address_t *);