initial commit

1 files changed, 332 insertions, 0 deletions

diff --git a/rules.c b/rules.c
new file mode 100644
index 0000000..3ad2a6a
--- /dev/null
+++ b/rules.c
@@ -0,0 +1,332 @@
+/*
+ * firewall3 - 3rd OpenWrt UCI firewall implementation
+ *
+ *   Copyright (C) 2013 Jo-Philipp Wich <jow@openwrt.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "rules.h"
+
+
+static struct fw3_option rule_opts[] = {
+	FW3_OPT("name",                string,   rule,     name),
+	FW3_OPT("family",              family,   rule,     family),
+
+	FW3_OPT("src",                 device,   rule,     src),
+	FW3_OPT("dest",                device,   rule,     dest),
+
+	FW3_OPT("ipset",               device,   rule,     ipset),
+
+	FW3_LIST("proto",              protocol, rule,     proto),
+
+	FW3_LIST("src_ip",             address,  rule,     ip_src),
+	FW3_LIST("src_mac",            mac,      rule,     mac_src),
+	FW3_LIST("src_port",           port,     rule,     port_src),
+
+	FW3_LIST("dest_ip",            address,  rule,     ip_dest),
+	FW3_LIST("dest_port",          port,     rule,     port_dest),
+
+	FW3_LIST("icmp_type",          icmptype, rule,     icmp_type),
+	FW3_OPT("extra",               string,   rule,     extra),
+
+	FW3_OPT("limit",               limit,    rule,     limit),
+	FW3_OPT("limit_burst",         int,      rule,     limit.burst),
+
+	FW3_OPT("target",              target,   rule,     target),
+};
+
+
+void
+fw3_load_rules(struct fw3_state *state, struct uci_package *p)
+{
+	struct uci_section *s;
+	struct uci_element *e;
+	struct fw3_rule *rule;
+
+	INIT_LIST_HEAD(&state->rules);
+
+	uci_foreach_element(&p->sections, e)
+	{
+		s = uci_to_section(e);
+
+		if (strcmp(s->type, "rule"))
+			continue;
+
+		rule = malloc(sizeof(*rule));
+
+		if (!rule)
+			continue;
+
+		memset(rule, 0, sizeof(*rule));
+
+		INIT_LIST_HEAD(&rule->proto);
+
+		INIT_LIST_HEAD(&rule->ip_src);
+		INIT_LIST_HEAD(&rule->mac_src);
+		INIT_LIST_HEAD(&rule->port_src);
+
+		INIT_LIST_HEAD(&rule->ip_dest);
+		INIT_LIST_HEAD(&rule->port_dest);
+
+		INIT_LIST_HEAD(&rule->icmp_type);
+
+		fw3_parse_options(rule, rule_opts, ARRAY_SIZE(rule_opts), s);
+
+		if (rule->src.invert || rule->dest.invert)
+		{
+			warn_elem(e, "must not have inverted 'src' or 'dest' options");
+			fw3_free_rule(rule);
+			continue;
+		}
+		else if (rule->src.set && !rule->src.any &&
+		         !(rule->_src = fw3_lookup_zone(state, rule->src.name)))
+		{
+			warn_elem(e, "refers to not existing zone '%s'", rule->src.name);
+			fw3_free_rule(rule);
+			continue;
+		}
+		else if (rule->dest.set && !rule->dest.any &&
+		         !(rule->_dest = fw3_lookup_zone(state, rule->dest.name)))
+		{
+			warn_elem(e, "refers to not existing zone '%s'", rule->dest.name);
+			fw3_free_rule(rule);
+			continue;
+		}
+		else if (rule->ipset.set && state->disable_ipsets)
+		{
+			warn_elem(e, "skipped due to disabled ipset support");
+			fw3_free_rule(rule);
+			continue;
+		}
+		else if (rule->ipset.set && !rule->ipset.any &&
+		         !(rule->_ipset = fw3_lookup_ipset(state, rule->ipset.name)))
+		{
+			warn_elem(e, "refers to not declared ipset '%s'", rule->ipset.name);
+			fw3_free_rule(rule);
+			continue;
+		}
+
+		if (!rule->_src && rule->target == FW3_TARGET_NOTRACK)
+		{
+			warn_elem(e, "is set to target NOTRACK but has no source assigned");
+			fw3_free_rule(rule);
+			continue;
+		}
+
+		if (!rule->_src && !rule->_dest && !rule->src.any && !rule->dest.any)
+		{
+			warn_elem(e, "has neither a source nor a destination zone assigned "
+			             "- assuming an output rule");
+		}
+
+		if (rule->target == FW3_TARGET_UNSPEC)
+		{
+			warn_elem(e, "has no target specified, defaulting to REJECT");
+			rule->target = FW3_TARGET_REJECT;
+		}
+		else if (rule->target > FW3_TARGET_NOTRACK)
+		{
+			warn_elem(e, "has invalid target specified, defaulting to REJECT");
+			rule->target = FW3_TARGET_REJECT;
+		}
+
+		if (rule->_dest)
+			rule->_dest->has_dest_target[rule->target] = true;
+
+		list_add_tail(&rule->list, &state->rules);
+		continue;
+	}
+}
+
+
+static void
+print_chain(struct fw3_rule *rule)
+{
+	char chain[256];
+
+	sprintf(chain, "delegate_output");
+
+	if (rule->target == FW3_TARGET_NOTRACK)
+	{
+		sprintf(chain, "zone_%s_notrack", rule->src.name);
+	}
+	else
+	{
+		if (rule->src.set)
+		{
+			if (!rule->src.any)
+			{
+				if (rule->dest.set)
+					sprintf(chain, "zone_%s_forward", rule->src.name);
+				else
+					sprintf(chain, "zone_%s_input", rule->src.name);
+			}
+			else
+			{
+				if (rule->dest.set)
+					sprintf(chain, "delegate_forward");
+				else
+					sprintf(chain, "delegate_input");
+			}
+		}
+
+		if (rule->dest.set && !rule->src.set)
+			sprintf(chain, "zone_%s_output", rule->dest.name);
+	}
+
+	fw3_pr("-A %s", chain);
+}
+
+static void print_target(struct fw3_rule *rule)
+{
+	char target[256];
+
+	switch(rule->target)
+	{
+	case FW3_TARGET_ACCEPT:
+		sprintf(target, "ACCEPT");
+		break;
+
+	case FW3_TARGET_DROP:
+		sprintf(target, "DROP");
+		break;
+
+	case FW3_TARGET_NOTRACK:
+		sprintf(target, "NOTRACK");
+		break;
+
+	default:
+		sprintf(target, "REJECT");
+		break;
+	}
+
+	if (rule->dest.set && !rule->dest.any)
+		fw3_pr(" -j zone_%s_dest_%s\n", rule->dest.name, target);
+	else if (!strcmp(target, "REJECT"))
+		fw3_pr(" -j reject\n");
+	else
+		fw3_pr(" -j %s\n", target);
+}
+
+static void
+print_rule(enum fw3_table table, enum fw3_family family,
+           struct fw3_rule *rule, struct fw3_protocol *proto,
+           struct fw3_address *sip, struct fw3_address *dip,
+           struct fw3_port *sport, struct fw3_port *dport,
+           struct fw3_mac *mac, struct fw3_icmptype *icmptype)
+{
+	if (!fw3_is_family(sip, family) || !fw3_is_family(dip, family))
+		return;
+
+	if (proto->protocol == 58 && family == FW3_FAMILY_V4)
+		return;
+
+	print_chain(rule);
+	fw3_format_ipset(rule->_ipset, rule->ipset.invert);
+	fw3_format_protocol(proto, family);
+	fw3_format_src_dest(sip, dip);
+	fw3_format_sport_dport(sport, dport);
+	fw3_format_icmptype(icmptype, family);
+	fw3_format_mac(mac);
+	fw3_format_limit(&rule->limit);
+	fw3_format_extra(rule->extra);
+	fw3_format_comment(rule->name);
+	print_target(rule);
+}
+
+static void
+expand_rule(enum fw3_table table, enum fw3_family family,
+            struct fw3_rule *rule, int num)
+{
+	struct fw3_protocol *proto;
+	struct fw3_address *sip;
+	struct fw3_address *dip;
+	struct fw3_port *sport;
+	struct fw3_port *dport;
+	struct fw3_mac *mac;
+	struct fw3_icmptype *icmptype;
+
+	struct list_head *sports = NULL;
+	struct list_head *dports = NULL;
+	struct list_head *icmptypes = NULL;
+
+	struct list_head empty;
+	INIT_LIST_HEAD(&empty);
+
+	if (!fw3_is_family(rule, family))
+		return;
+
+	if ((table == FW3_TABLE_RAW && rule->target != FW3_TARGET_NOTRACK) ||
+	    (table != FW3_TABLE_FILTER))
+		return;
+
+	if (rule->name)
+		info("   * Rule '%s'", rule->name);
+	else
+		info("   * Rule #%u", num);
+
+	list_for_each_entry(proto, &rule->proto, list)
+	{
+		/* icmp / ipv6-icmp */
+		if (proto->protocol == 1 || proto->protocol == 58)
+		{
+			sports = &empty;
+			dports = &empty;
+			icmptypes = &rule->icmp_type;
+		}
+		else
+		{
+			sports = &rule->port_src;
+			dports = &rule->port_dest;
+			icmptypes = &empty;
+		}
+
+		fw3_foreach(sip, &rule->ip_src)
+		fw3_foreach(dip, &rule->ip_dest)
+		fw3_foreach(sport, sports)
+		fw3_foreach(dport, dports)
+		fw3_foreach(mac, &rule->mac_src)
+		fw3_foreach(icmptype, icmptypes)
+			print_rule(table, family, rule, proto, sip, dip, sport, dport,
+			           mac, icmptype);
+	}
+}
+
+void
+fw3_print_rules(enum fw3_table table, enum fw3_family family,
+                struct fw3_state *state)
+{
+	int num = 0;
+	struct fw3_rule *rule;
+
+	list_for_each_entry(rule, &state->rules, list)
+		expand_rule(table, family, rule, num++);
+}
+
+void
+fw3_free_rule(struct fw3_rule *rule)
+{
+	fw3_free_list(&rule->proto);
+
+	fw3_free_list(&rule->ip_src);
+	fw3_free_list(&rule->mac_src);
+	fw3_free_list(&rule->port_dest);
+
+	fw3_free_list(&rule->ip_dest);
+	fw3_free_list(&rule->port_dest);
+
+	fw3_free_list(&rule->icmp_type);
+
+	free(rule);
+}