+/*
+ * firewall3 - 3rd OpenWrt UCI firewall implementation
+ *
+ * Copyright (C) 2014 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 "snats.h"
+
+
+const struct fw3_option fw3_snat_opts[] = {
+ FW3_OPT("enabled", bool, snat, enabled),
+
+ FW3_OPT("name", string, snat, name),
+ FW3_OPT("family", family, snat, family),
+
+ FW3_OPT("src", device, snat, src),
+
+ FW3_OPT("ipset", setmatch, snat, ipset),
+
+ FW3_LIST("proto", protocol, snat, proto),
+
+ FW3_OPT("src_ip", network, snat, ip_src),
+ FW3_OPT("src_port", port, snat, port_src),
+
+ FW3_OPT("snat_ip", network, snat, ip_snat),
+ FW3_OPT("snat_port", port, snat, port_snat),
+
+ FW3_OPT("dest_ip", network, snat, ip_dest),
+ FW3_OPT("dest_port", port, snat, port_dest),
+
+ FW3_OPT("extra", string, snat, extra),
+
+ FW3_OPT("limit", limit, snat, limit),
+ FW3_OPT("limit_burst", int, snat, limit.burst),
+
+ FW3_OPT("utc_time", bool, snat, time.utc),
+ FW3_OPT("start_date", date, snat, time.datestart),
+ FW3_OPT("stop_date", date, snat, time.datestop),
+ FW3_OPT("start_time", time, snat, time.timestart),
+ FW3_OPT("stop_time", time, snat, time.timestop),
+ FW3_OPT("weekdays", weekdays, snat, time.weekdays),
+ FW3_OPT("monthdays", monthdays, snat, time.monthdays),
+
+ FW3_OPT("mark", mark, snat, mark),
+
+ FW3_OPT("target", target, snat, target),
+
+ { }
+};
+
+
+static bool
+check_families(struct uci_element *e, struct fw3_snat *r)
+{
+ if (r->family == FW3_FAMILY_ANY)
+ return true;
+
+ if (r->_src && r->_src->family && r->_src->family != r->family)
+ {
+ warn_elem(e, "refers to source zone with different family");
+ return false;
+ }
+
+ if (r->ipset.ptr && r->ipset.ptr->family &&
+ r->ipset.ptr->family != r->family)
+ {
+ warn_elem(e, "refers to ipset with different family");
+ return false;
+ }
+
+ if (r->ip_src.family && r->ip_src.family != r->family)
+ {
+ warn_elem(e, "uses source ip with different family");
+ return false;
+ }
+
+ if (r->ip_dest.family && r->ip_dest.family != r->family)
+ {
+ warn_elem(e, "uses destination ip with different family");
+ return false;
+ }
+
+ if (r->ip_snat.family && r->ip_snat.family != r->family)
+ {
+ warn_elem(e, "uses snat ip with different family");
+ return false;
+ }
+
+ return true;
+}
+
+void
+fw3_load_snats(struct fw3_state *state, struct uci_package *p)
+{
+ struct uci_section *s;
+ struct uci_element *e;
+ struct fw3_snat *snat;
+
+ INIT_LIST_HEAD(&state->snats);
+
+ uci_foreach_element(&p->sections, e)
+ {
+ s = uci_to_section(e);
+
+ if (strcmp(s->type, "nat"))
+ continue;
+
+ snat = malloc(sizeof(*snat));
+
+ if (!snat)
+ continue;
+
+ memset(snat, 0, sizeof(*snat));
+
+ INIT_LIST_HEAD(&snat->proto);
+
+ snat->enabled = true;
+
+ if (!fw3_parse_options(snat, fw3_snat_opts, s))
+ {
+ warn_elem(e, "skipped due to invalid options");
+ fw3_free_snat(snat);
+ continue;
+ }
+
+ if (!snat->enabled)
+ {
+ fw3_free_snat(snat);
+ continue;
+ }
+
+ if (snat->src.invert)
+ {
+ warn_elem(e, "must not have an inverted source");
+ fw3_free_snat(snat);
+ continue;
+ }
+ else if (snat->src.set && !snat->src.any &&
+ !(snat->_src = fw3_lookup_zone(state, snat->src.name)))
+ {
+ warn_elem(e, "refers to not existing zone '%s'", snat->src.name);
+ fw3_free_snat(snat);
+ continue;
+ }
+ else if (snat->ipset.set && state->disable_ipsets)
+ {
+ warn_elem(e, "skipped due to disabled ipset support");
+ fw3_free_snat(snat);
+ continue;
+ }
+ else if (snat->ipset.set &&
+ !(snat->ipset.ptr = fw3_lookup_ipset(state, snat->ipset.name)))
+ {
+ warn_elem(e, "refers to unknown ipset '%s'", snat->ipset.name);
+ fw3_free_snat(snat);
+ continue;
+ }
+
+ if (!check_families(e, snat))
+ {
+ fw3_free_snat(snat);
+ continue;
+ }
+
+ if (snat->target == FW3_FLAG_UNSPEC)
+ {
+ warn_elem(e, "has no target specified, defaulting to MASQUERADE");
+ snat->target = FW3_FLAG_MASQUERADE;
+ }
+ else if (snat->target < FW3_FLAG_SNAT || snat->target > FW3_FLAG_MASQUERADE)
+ {
+ warn_elem(e, "has invalid target specified, defaulting to MASQUERADE");
+ snat->target = FW3_FLAG_MASQUERADE;
+ }
+
+ if (snat->target == FW3_FLAG_SNAT &&
+ !snat->ip_snat.set && !snat->port_snat.set)
+ {
+ warn_elem(e, "needs either 'snat_ip' or 'snat_port' for SNAT");
+ fw3_free_snat(snat);
+ continue;
+ }
+ else if (snat->target == FW3_FLAG_MASQUERADE && snat->ip_snat.set)
+ {
+ warn_elem(e, "must not use 'snat_ip' for MASQUERADE");
+ fw3_free_snat(snat);
+ continue;
+ }
+ else if (snat->target == FW3_FLAG_MASQUERADE && snat->port_snat.set)
+ {
+ warn_elem(e, "must not use 'snat_port' for MASQUERADE");
+ fw3_free_snat(snat);
+ continue;
+ }
+
+ if (list_empty(&snat->proto))
+ {
+ warn_elem(e, "does not specify a protocol, assuming all");
+ fw3_parse_protocol(&snat->proto, "all", true);
+ }
+
+ if (snat->_src)
+ {
+ set(snat->_src->flags, FW3_FAMILY_V4, FW3_FLAG_SNAT);
+ snat->_src->conntrack = true;
+ }
+
+ list_add_tail(&snat->list, &state->snats);
+ }
+}
+
+static void
+append_chain(struct fw3_ipt_rule *r, struct fw3_snat *snat)
+{
+ if (snat->_src)
+ fw3_ipt_rule_append(r, "zone_%s_postrouting", snat->src.name);
+ else
+ fw3_ipt_rule_append(r, "delegate_postrouting");
+}
+
+static void
+set_target(struct fw3_ipt_rule *r, struct fw3_snat *snat,
+ struct fw3_protocol *proto)
+{
+ char buf[sizeof("255.255.255.255:65535-65535\0")];
+
+ if (snat->target == FW3_FLAG_SNAT)
+ {
+ buf[0] = '\0';
+
+ if (snat->ip_snat.set)
+ {
+ inet_ntop(AF_INET, &snat->ip_snat.address.v4, buf, sizeof(buf));
+ }
+
+ if (snat->port_snat.set && proto && !proto->any &&
+ (proto->protocol == 6 || proto->protocol == 17))
+ {
+ if (snat->port_snat.port_min == snat->port_snat.port_max)
+ sprintf(buf + strlen(buf), ":%u", snat->port_snat.port_min);
+ else
+ sprintf(buf + strlen(buf), ":%u-%u",
+ snat->port_snat.port_min, snat->port_snat.port_max);
+ }
+
+ fw3_ipt_rule_target(r, "SNAT");
+ fw3_ipt_rule_addarg(r, false, "--to-source", buf);
+ }
+ else
+ {
+ fw3_ipt_rule_target(r, "MASQUERADE");
+ }
+}
+
+static void
+set_comment(struct fw3_ipt_rule *r, const char *name, int num)
+{
+ if (name)
+ fw3_ipt_rule_comment(r, name);
+ else
+ fw3_ipt_rule_comment(r, "@nat[%u]", num);
+}
+
+static void
+print_snat(struct fw3_ipt_handle *h, struct fw3_state *state,
+ struct fw3_snat *snat, int num, struct fw3_protocol *proto)
+{
+ struct fw3_ipt_rule *r;
+ struct fw3_address *src, *dst;
+ struct fw3_port *spt, *dpt;
+
+ switch (h->table)
+ {
+ case FW3_TABLE_NAT:
+ src = &snat->ip_src;
+ dst = &snat->ip_dest;
+ spt = &snat->port_src;
+ dpt = &snat->port_dest;
+
+ r = fw3_ipt_rule_create(h, proto, NULL, NULL, src, dst);
+ fw3_ipt_rule_sport_dport(r, spt, dpt);
+ fw3_ipt_rule_ipset(r, &snat->ipset);
+ fw3_ipt_rule_limit(r, &snat->limit);
+ fw3_ipt_rule_time(r, &snat->time);
+ fw3_ipt_rule_mark(r, &snat->mark);
+ set_target(r, snat, proto);
+ fw3_ipt_rule_extra(r, snat->extra);
+ set_comment(r, snat->name, num);
+ append_chain(r, snat);
+ break;
+
+ default:
+ break;
+ }
+}
+
+static void
+expand_snat(struct fw3_ipt_handle *handle, struct fw3_state *state,
+ struct fw3_snat *snat, int num)
+{
+ struct fw3_protocol *proto;
+
+ if (snat->name)
+ info(" * NAT '%s'", snat->name);
+ else
+ info(" * NAT #%u", num);
+
+ if (!fw3_is_family(snat->_src, handle->family))
+ {
+ info(" ! Skipping due to different family of zone");
+ return;
+ }
+
+ if (!fw3_is_family(&snat->ip_src, handle->family) ||
+ !fw3_is_family(&snat->ip_dest, handle->family) ||
+ !fw3_is_family(&snat->ip_snat, handle->family))
+ {
+ if (!snat->ip_src.resolved ||
+ !snat->ip_dest.resolved ||
+ !snat->ip_snat.resolved)
+ info(" ! Skipping due to different family of ip address");
+
+ return;
+ }
+
+ if (snat->ipset.ptr)
+ {
+ if (!fw3_is_family(snat->ipset.ptr, handle->family))
+ {
+ info(" ! Skipping due to different family in ipset");
+ return;
+ }
+
+ if (!fw3_check_ipset(snat->ipset.ptr))
+ {
+ info(" ! Skipping due to missing ipset '%s'",
+ snat->ipset.ptr->external ?
+ snat->ipset.ptr->external : snat->ipset.ptr->name);
+ return;
+ }
+
+ set(snat->ipset.ptr->flags, handle->family, handle->family);
+ }
+
+ fw3_foreach(proto, &snat->proto)
+ print_snat(handle, state, snat, num, proto);
+}
+
+void
+fw3_print_snats(struct fw3_ipt_handle *handle, struct fw3_state *state)
+{
+ int num = 0;
+ struct fw3_snat *snat;
+
+ if (handle->family == FW3_FAMILY_V6)
+ return;
+
+ if (handle->table != FW3_TABLE_NAT)
+ return;
+
+ list_for_each_entry(snat, &state->snats, list)
+ expand_snat(handle, state, snat, num++);
+}
projects / project / firewall3.git / commitdiff