#include <linux/config.h>
#include <linux/types.h>
+#include <linux/inetdevice.h>
#include <linux/ip.h>
#include <linux/timer.h>
#include <linux/module.h>
#include <net/protocol.h>
#include <net/ip.h>
#include <net/checksum.h>
+#include <net/route.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv4/ip_nat_rule.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#endif
/* Lock protects masq region inside conntrack */
-static DECLARE_RWLOCK(masq_lock);
+static DEFINE_RWLOCK(masq_lock);
/* FIXME: Multiple targets. --RR */
static int
masquerade_check(const char *tablename,
- const struct ipt_entry *e,
+ const void *e,
+ const struct xt_target *target,
void *targinfo,
unsigned int targinfosize,
unsigned int hook_mask)
{
- const struct ip_nat_multi_range *mr = targinfo;
+ const struct ip_nat_multi_range_compat *mr = targinfo;
- if (strcmp(tablename, "nat") != 0) {
- DEBUGP("masquerade_check: bad table `%s'.\n", tablename);
- return 0;
- }
- if (targinfosize != IPT_ALIGN(sizeof(*mr))) {
- DEBUGP("masquerade_check: size %u != %u.\n",
- targinfosize, sizeof(*mr));
- return 0;
- }
- if (hook_mask & ~(1 << NF_IP_POST_ROUTING)) {
- DEBUGP("masquerade_check: bad hooks %x.\n", hook_mask);
- return 0;
- }
if (mr->range[0].flags & IP_NAT_RANGE_MAP_IPS) {
DEBUGP("masquerade_check: bad MAP_IPS.\n");
return 0;
const struct net_device *in,
const struct net_device *out,
unsigned int hooknum,
+ const struct xt_target *target,
const void *targinfo,
void *userinfo)
{
struct ip_conntrack *ct;
enum ip_conntrack_info ctinfo;
- const struct ip_nat_multi_range *mr;
- struct ip_nat_multi_range newrange;
- u_int32_t newsrc;
+ const struct ip_nat_multi_range_compat *mr;
+ struct ip_nat_range newrange;
struct rtable *rt;
+ u_int32_t newsrc;
IP_NF_ASSERT(hooknum == NF_IP_POST_ROUTING);
- /* FIXME: For the moment, don't do local packets, breaks
- testsuite for 2.3.49 --RR */
- if ((*pskb)->sk)
- return NF_ACCEPT;
-
ct = ip_conntrack_get(*pskb, &ctinfo);
- IP_NF_ASSERT(ct && (ctinfo == IP_CT_NEW
- || ctinfo == IP_CT_RELATED));
+ IP_NF_ASSERT(ct && (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED
+ || ctinfo == IP_CT_RELATED + IP_CT_IS_REPLY));
- mr = targinfo;
+ /* Source address is 0.0.0.0 - locally generated packet that is
+ * probably not supposed to be masqueraded.
+ */
+ if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.ip == 0)
+ return NF_ACCEPT;
- {
- struct flowi fl = { .nl_u = { .ip4_u =
- { .daddr = (*pskb)->nh.iph->daddr,
- .tos = (RT_TOS((*pskb)->nh.iph->tos) |
- RTO_CONN),
-#ifdef CONFIG_IP_ROUTE_FWMARK
- .fwmark = (*pskb)->nfmark
-#endif
- } } };
- if (ip_route_output_key(&rt, &fl) != 0) {
- /* Funky routing can do this. */
- if (net_ratelimit())
- printk("MASQUERADE:"
- " No route: Rusty's brain broke!\n");
- return NF_DROP;
- }
- if (rt->u.dst.dev != out) {
- if (net_ratelimit())
- printk("MASQUERADE:"
- " Route sent us somewhere else.\n");
- ip_rt_put(rt);
- return NF_DROP;
- }
+ mr = targinfo;
+ rt = (struct rtable *)(*pskb)->dst;
+ newsrc = inet_select_addr(out, rt->rt_gateway, RT_SCOPE_UNIVERSE);
+ if (!newsrc) {
+ printk("MASQUERADE: %s ate my IP address\n", out->name);
+ return NF_DROP;
}
- newsrc = rt->rt_src;
- DEBUGP("newsrc = %u.%u.%u.%u\n", NIPQUAD(newsrc));
- ip_rt_put(rt);
-
- WRITE_LOCK(&masq_lock);
+ write_lock_bh(&masq_lock);
ct->nat.masq_index = out->ifindex;
- WRITE_UNLOCK(&masq_lock);
+ write_unlock_bh(&masq_lock);
/* Transfer from original range. */
- newrange = ((struct ip_nat_multi_range)
- { 1, { { mr->range[0].flags | IP_NAT_RANGE_MAP_IPS,
- newsrc, newsrc,
- mr->range[0].min, mr->range[0].max } } });
+ newrange = ((struct ip_nat_range)
+ { mr->range[0].flags | IP_NAT_RANGE_MAP_IPS,
+ newsrc, newsrc,
+ mr->range[0].min, mr->range[0].max });
/* Hand modified range to generic setup. */
return ip_nat_setup_info(ct, &newrange, hooknum);
}
static inline int
-device_cmp(const struct ip_conntrack *i, void *_ina)
+device_cmp(struct ip_conntrack *i, void *ifindex)
{
- int ret = 0;
- struct in_ifaddr *ina = _ina;
+ int ret;
- READ_LOCK(&masq_lock);
- /* If it's masquerading out this interface with a different address,
- or we don't know the new address of this interface. */
- if (i->nat.masq_index == ina->ifa_dev->dev->ifindex
- && i->tuplehash[IP_CT_DIR_REPLY].tuple.dst.ip != ina->ifa_address)
- ret = 1;
- READ_UNLOCK(&masq_lock);
+ read_lock_bh(&masq_lock);
+ ret = (i->nat.masq_index == (int)(long)ifindex);
+ read_unlock_bh(&masq_lock);
return ret;
}
+static int masq_device_event(struct notifier_block *this,
+ unsigned long event,
+ void *ptr)
+{
+ struct net_device *dev = ptr;
+
+ if (event == NETDEV_DOWN) {
+ /* Device was downed. Search entire table for
+ conntracks which were associated with that device,
+ and forget them. */
+ IP_NF_ASSERT(dev->ifindex != 0);
+
+ ip_ct_iterate_cleanup(device_cmp, (void *)(long)dev->ifindex);
+ }
+
+ return NOTIFY_DONE;
+}
+
static int masq_inet_event(struct notifier_block *this,
unsigned long event,
void *ptr)
{
- /* For some configurations, interfaces often come back with
- * the same address. If not, clean up old conntrack
- * entries. */
- if (event == NETDEV_UP)
- ip_ct_selective_cleanup(device_cmp, ptr);
+ struct net_device *dev = ((struct in_ifaddr *)ptr)->ifa_dev->dev;
+
+ if (event == NETDEV_DOWN) {
+ /* IP address was deleted. Search entire table for
+ conntracks which were associated with that device,
+ and forget them. */
+ IP_NF_ASSERT(dev->ifindex != 0);
+
+ ip_ct_iterate_cleanup(device_cmp, (void *)(long)dev->ifindex);
+ }
return NOTIFY_DONE;
}
+static struct notifier_block masq_dev_notifier = {
+ .notifier_call = masq_device_event,
+};
+
static struct notifier_block masq_inet_notifier = {
.notifier_call = masq_inet_event,
};
static struct ipt_target masquerade = {
.name = "MASQUERADE",
.target = masquerade_target,
+ .targetsize = sizeof(struct ip_nat_multi_range_compat),
+ .table = "nat",
+ .hooks = 1 << NF_IP_POST_ROUTING,
.checkentry = masquerade_check,
.me = THIS_MODULE,
};
-static int __init init(void)
+static int __init ipt_masquerade_init(void)
{
int ret;
ret = ipt_register_target(&masquerade);
- if (ret == 0)
+ if (ret == 0) {
+ /* Register for device down reports */
+ register_netdevice_notifier(&masq_dev_notifier);
/* Register IP address change reports */
register_inetaddr_notifier(&masq_inet_notifier);
+ }
return ret;
}
-static void __exit fini(void)
+static void __exit ipt_masquerade_fini(void)
{
ipt_unregister_target(&masquerade);
+ unregister_netdevice_notifier(&masq_dev_notifier);
unregister_inetaddr_notifier(&masq_inet_notifier);
}
-module_init(init);
-module_exit(fini);
+module_init(ipt_masquerade_init);
+module_exit(ipt_masquerade_fini);