firewall3: Improve ipset support

This patch is an attempt at improving the ipset support in firewall3.
The following changes have been made:

* The enabled option did not work properly for ipsets, as it was not
checked on create/destroy of a set. After this commit, sets are only
created/destroyed if enabled is set to true.

* Add support for reloading, or recreating, ipsets on firewall reload.
By setting "reload_set" to true, the set will be destroyed and then
re-created when the firewall is reloaded. My use-case for "reload_set"
was to reset sets populated by dnsmasq, without having to restart the
firewall or resort to scripts.

* Add support for the counters and comment extensions. By setting
"counters" or "comment" to true, then counters or comments are added to
the set.

Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com>
re-ordered additional variables
dropped enum OPT_COMMENT & OPT_COUNTERS as unused
implemented exponential delay whilst waiting for ipset deletion/creation
fixed delays made firewall unresponsive for too long on reloads
Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

ipsets.c

@@ -21,6 +21,9 @@
 
 const struct fw3_option fw3_ipset_opts[] = {
 	FW3_OPT("enabled",       bool,           ipset,     enabled),
+	FW3_OPT("reload_set",	 bool,           ipset,     reload_set),
+	FW3_OPT("counters",	 bool,           ipset,     counters),
+	FW3_OPT("comment",	 bool,           ipset,     comment),
 
 	FW3_OPT("name",          string,         ipset,     name),
 	FW3_OPT("family",        family,         ipset,     family),
@@ -204,6 +207,10 @@ check_types(struct uci_element *e, struct fw3_ipset *ipset)
 static bool
 check_ipset(struct fw3_state *state, struct fw3_ipset *ipset, struct uci_element *e)
 {
+	if (!ipset->enabled) {
+		return false;
+	}
+
 	if (ipset->external)
 	{
 		if (!*ipset->external)
@@ -252,8 +259,11 @@ fw3_alloc_ipset(struct fw3_state *state)
 	INIT_LIST_HEAD(&ipset->datatypes);
 	INIT_LIST_HEAD(&ipset->entries);
 
-	ipset->enabled = true;
-	ipset->family  = FW3_FAMILY_V4;
+	ipset->comment    = false;
+	ipset->counters   = false;
+	ipset->enabled    = true;
+	ipset->family     = FW3_FAMILY_V4;
+	ipset->reload_set = false;
 
 	list_add_tail(&ipset->list, &state->ipsets);
 
@@ -389,6 +399,12 @@ create_ipset(struct fw3_ipset *ipset, struct fw3_state *state)
 	if (ipset->hashsize > 0)
 		fw3_pr(" hashsize %u", ipset->hashsize);
 
+	if (ipset->counters)
+		fw3_pr(" counters");
+
+	if (ipset->comment)
+		fw3_pr(" comment");
+
 	fw3_pr("\n");
 
 	list_for_each_entry(entry, &ipset->entries, list)
@@ -398,9 +414,10 @@ create_ipset(struct fw3_ipset *ipset, struct fw3_state *state)
 }
 
 void
-fw3_create_ipsets(struct fw3_state *state)
+fw3_create_ipsets(struct fw3_state *state, enum fw3_family family,
+		  bool reload_set)
 {
-	int tries;
+	unsigned int delay, tries;
 	bool exec = false;
 	struct fw3_ipset *ipset;
 
@@ -410,6 +427,10 @@ fw3_create_ipsets(struct fw3_state *state)
 	/* spawn ipsets */
 	list_for_each_entry(ipset, &state->ipsets, list)
 	{
+		if (ipset->family != family ||
+		    (reload_set && !ipset->reload_set))
+			continue;
+
 		if (ipset->external)
 			continue;
 
@@ -430,27 +451,36 @@ fw3_create_ipsets(struct fw3_state *state)
 		fw3_command_close();
 	}
 
-	/* wait for ipsets to appear */
+	/* wait a little expontially for ipsets to appear */
 	list_for_each_entry(ipset, &state->ipsets, list)
 	{
 		if (ipset->external)
 			continue;
 
+		delay = 5;
 		for (tries = 0; !fw3_check_ipset(ipset) && tries < 10; tries++)
-			usleep(50000);
+			usleep(delay<<1);
 	}
 }
 
 void
-fw3_destroy_ipsets(struct fw3_state *state)
+fw3_destroy_ipsets(struct fw3_state *state, enum fw3_family family,
+		   bool reload_set)
 {
-	int tries;
+	unsigned int delay, tries;
 	bool exec = false;
 	struct fw3_ipset *ipset;
 
+	if (state->disable_ipsets)
+		return;
+
 	/* destroy ipsets */
 	list_for_each_entry(ipset, &state->ipsets, list)
 	{
+		if (ipset->family != family ||
+		    (reload_set && !ipset->reload_set))
+			continue;
+
 		if (!exec)
 		{
 			exec = fw3_command_pipe(false, "ipset", "-exist", "-");
@@ -477,8 +507,9 @@ fw3_destroy_ipsets(struct fw3_state *state)
 		if (ipset->external)
 			continue;
 
+		delay = 5;
 		for (tries = 0; fw3_check_ipset(ipset) && tries < 10; tries++)
-			usleep(50000);
+			usleep(delay<<1);
 	}
 }
 

ipsets.h

@@ -28,8 +28,10 @@
 extern const struct fw3_option fw3_ipset_opts[];
 
 void fw3_load_ipsets(struct fw3_state *state, struct uci_package *p, struct blob_attr *a);
-void fw3_create_ipsets(struct fw3_state *state);
-void fw3_destroy_ipsets(struct fw3_state *state);
+void fw3_create_ipsets(struct fw3_state *state, enum fw3_family family,
+		       bool reload_set);
+void fw3_destroy_ipsets(struct fw3_state *state, enum fw3_family family,
+			bool reload_set);
 
 struct fw3_ipset * fw3_lookup_ipset(struct fw3_state *state, const char *name);
 

main.c

@@ -224,8 +224,10 @@ stop(bool complete)
 		rv = 0;
 	}
 
-	if (run_state)
-		fw3_destroy_ipsets(run_state);
+	if (run_state) {
+		for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
+			fw3_destroy_ipsets(run_state, family, false);
+	}
 
 	if (complete)
 		fw3_flush_conntrack(NULL);
@@ -244,11 +246,11 @@ start(void)
 	enum fw3_table table;
 	struct fw3_ipt_handle *handle;
 
-	if (!print_family)
-		fw3_create_ipsets(cfg_state);
-
 	for (family = FW3_FAMILY_V4; family <= FW3_FAMILY_V6; family++)
 	{
+		if (!print_family)
+			fw3_create_ipsets(cfg_state, family, false);
+
 		if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 			continue;
 
@@ -352,6 +354,8 @@ reload(void)
 			fw3_ipt_close(handle);
 		}
 
+		fw3_destroy_ipsets(run_state, family, true);
+
 		family_set(run_state, family, false);
 		family_set(cfg_state, family, false);
 
@@ -359,6 +363,8 @@ start:
 		if (family == FW3_FAMILY_V6 && cfg_state->defaults.disable_ipv6)
 			continue;
 
+		fw3_create_ipsets(cfg_state, family, true);
+
 		for (table = FW3_TABLE_FILTER; table <= FW3_TABLE_RAW; table++)
 		{
 			if (!fw3_has_table(family == FW3_FAMILY_V6, fw3_flag_names[table]))

options.h

@@ -501,6 +501,10 @@ struct fw3_ipset
 	struct list_head list;
 
 	bool enabled;
+	bool reload_set;
+	bool counters;
+	bool comment;
+
 	const char *name;
 	enum fw3_family family;
 

utils.c

@@ -585,6 +585,11 @@ write_ipset_uci(struct uci_context *ctx, struct fw3_ipset *s,
 	ptr.value  = s->name;
 	uci_set(ctx, &ptr);
 
+	ptr.o      = NULL;
+	ptr.option = "reload_set";
+	ptr.value  = s->reload_set ? "true" : "false";
+	uci_set(ctx, &ptr);
+
 	ptr.o      = NULL;
 	ptr.option = "storage";
 	ptr.value  = fw3_ipset_method_names[s->method];