* (c) 2000 Gerd Knorr <kraxel@bytesex.org>
* Nov 2002: Martin Bene <martin.bene@icomedias.com>:
* only ignore TIME_WAIT or gone connections
- * Copyright © Jan Engelhardt <jengelh@gmx.de>, 2007
+ * (C) CC Computer Consultants GmbH, 2007
+ * Contact: <jengelh@computergmbh.de>
*
* based on ...
*
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_tuple.h>
+#include <net/netfilter/nf_conntrack_zones.h>
/* we will save the tuples of all connections we care about */
struct xt_connlimit_conn {
spinlock_t lock;
};
-static u_int32_t connlimit_rnd;
-static bool connlimit_rnd_inited;
+static u_int32_t connlimit_rnd __read_mostly;
+static bool connlimit_rnd_inited __read_mostly;
static inline unsigned int connlimit_iphash(__be32 addr)
{
- if (unlikely(!connlimit_rnd_inited)) {
- get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
- connlimit_rnd_inited = true;
- }
return jhash_1word((__force __u32)addr, connlimit_rnd) & 0xFF;
}
static inline unsigned int
-connlimit_iphash6(const union nf_conntrack_address *addr,
- const union nf_conntrack_address *mask)
+connlimit_iphash6(const union nf_inet_addr *addr,
+ const union nf_inet_addr *mask)
{
- union nf_conntrack_address res;
+ union nf_inet_addr res;
unsigned int i;
- if (unlikely(!connlimit_rnd_inited)) {
- get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
- connlimit_rnd_inited = true;
- }
-
for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i)
res.ip6[i] = addr->ip6[i] & mask->ip6[i];
static inline bool already_closed(const struct nf_conn *conn)
{
- u_int16_t proto = conn->tuplehash[0].tuple.dst.protonum;
-
- if (proto == IPPROTO_TCP)
- return conn->proto.tcp.state == TCP_CONNTRACK_TIME_WAIT;
+ if (nf_ct_protonum(conn) == IPPROTO_TCP)
+ return conn->proto.tcp.state == TCP_CONNTRACK_TIME_WAIT ||
+ conn->proto.tcp.state == TCP_CONNTRACK_CLOSE;
else
return 0;
}
static inline unsigned int
-same_source_net(const union nf_conntrack_address *addr,
- const union nf_conntrack_address *mask,
- const union nf_conntrack_address *u3, unsigned int family)
+same_source_net(const union nf_inet_addr *addr,
+ const union nf_inet_addr *mask,
+ const union nf_inet_addr *u3, u_int8_t family)
{
- if (family == AF_INET) {
+ if (family == NFPROTO_IPV4) {
return (addr->ip & mask->ip) == (u3->ip & mask->ip);
} else {
- union nf_conntrack_address lh, rh;
+ union nf_inet_addr lh, rh;
unsigned int i;
for (i = 0; i < ARRAY_SIZE(addr->ip6); ++i) {
}
}
-static int count_them(struct xt_connlimit_data *data,
+static int count_them(struct net *net,
+ struct xt_connlimit_data *data,
const struct nf_conntrack_tuple *tuple,
- const union nf_conntrack_address *addr,
- const union nf_conntrack_address *mask,
- const struct xt_match *match)
+ const union nf_inet_addr *addr,
+ const union nf_inet_addr *mask,
+ u_int8_t family)
{
- struct nf_conntrack_tuple_hash *found;
+ const struct nf_conntrack_tuple_hash *found;
struct xt_connlimit_conn *conn;
struct xt_connlimit_conn *tmp;
struct nf_conn *found_ct;
bool addit = true;
int matches = 0;
-
- if (match->family == AF_INET6)
+ if (family == NFPROTO_IPV6)
hash = &data->iphash[connlimit_iphash6(addr, mask)];
else
hash = &data->iphash[connlimit_iphash(addr->ip & mask->ip)];
- read_lock_bh(&nf_conntrack_lock);
+ rcu_read_lock();
/* check the saved connections */
list_for_each_entry_safe(conn, tmp, hash, list) {
- found = __nf_conntrack_find(&conn->tuple, NULL);
+ found = nf_conntrack_find_get(net, NF_CT_DEFAULT_ZONE,
+ &conn->tuple);
found_ct = NULL;
if (found != NULL)
* we do not care about connections which are
* closed already -> ditch it
*/
+ nf_ct_put(found_ct);
list_del(&conn->list);
kfree(conn);
continue;
}
- if (same_source_net(addr, mask, &conn->tuple.src.u3,
- match->family))
+ if (same_source_net(addr, mask, &conn->tuple.src.u3, family))
/* same source network -> be counted! */
++matches;
+ nf_ct_put(found_ct);
}
- read_unlock_bh(&nf_conntrack_lock);
+ rcu_read_unlock();
if (addit) {
/* save the new connection in our list */
return matches;
}
-static bool connlimit_match(const struct sk_buff *skb,
- const struct net_device *in,
- const struct net_device *out,
- const struct xt_match *match,
- const void *matchinfo, int offset,
- unsigned int protoff, bool *hotdrop)
+static bool
+connlimit_mt(const struct sk_buff *skb, const struct xt_match_param *par)
{
- const struct xt_connlimit_info *info = matchinfo;
- union nf_conntrack_address addr, mask;
+ struct net *net = dev_net(par->in ? par->in : par->out);
+ const struct xt_connlimit_info *info = par->matchinfo;
+ union nf_inet_addr addr;
struct nf_conntrack_tuple tuple;
const struct nf_conntrack_tuple *tuple_ptr = &tuple;
enum ip_conntrack_info ctinfo;
if (ct != NULL)
tuple_ptr = &ct->tuplehash[0].tuple;
else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
- match->family, &tuple))
+ par->family, &tuple))
goto hotdrop;
- if (match->family == AF_INET6) {
+ if (par->family == NFPROTO_IPV6) {
const struct ipv6hdr *iph = ipv6_hdr(skb);
memcpy(&addr.ip6, &iph->saddr, sizeof(iph->saddr));
- memcpy(&mask.ip6, info->v6_mask, sizeof(info->v6_mask));
} else {
const struct iphdr *iph = ip_hdr(skb);
addr.ip = iph->saddr;
- mask.ip = info->v4_mask;
}
spin_lock_bh(&info->data->lock);
- connections = count_them(info->data, tuple_ptr, &addr, &mask, match);
+ connections = count_them(net, info->data, tuple_ptr, &addr,
+ &info->mask, par->family);
spin_unlock_bh(&info->data->lock);
if (connections < 0) {
/* kmalloc failed, drop it entirely */
- *hotdrop = true;
+ *par->hotdrop = true;
return false;
}
return (connections > info->limit) ^ info->inverse;
hotdrop:
- *hotdrop = true;
+ *par->hotdrop = true;
return false;
}
-static bool connlimit_check(const char *tablename, const void *ip,
- const struct xt_match *match, void *matchinfo,
- unsigned int hook_mask)
+static bool connlimit_mt_check(const struct xt_mtchk_param *par)
{
- struct xt_connlimit_info *info = matchinfo;
+ struct xt_connlimit_info *info = par->matchinfo;
unsigned int i;
- if (nf_ct_l3proto_try_module_get(match->family) < 0) {
+ if (unlikely(!connlimit_rnd_inited)) {
+ get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
+ connlimit_rnd_inited = true;
+ }
+ if (nf_ct_l3proto_try_module_get(par->family) < 0) {
printk(KERN_WARNING "cannot load conntrack support for "
- "address family %u\n", match->family);
+ "address family %u\n", par->family);
return false;
}
/* init private data */
info->data = kmalloc(sizeof(struct xt_connlimit_data), GFP_KERNEL);
if (info->data == NULL) {
- nf_ct_l3proto_module_put(match->family);
+ nf_ct_l3proto_module_put(par->family);
return false;
}
return true;
}
-static void connlimit_destroy(const struct xt_match *match, void *matchinfo)
+static void connlimit_mt_destroy(const struct xt_mtdtor_param *par)
{
- struct xt_connlimit_info *info = matchinfo;
+ const struct xt_connlimit_info *info = par->matchinfo;
struct xt_connlimit_conn *conn;
struct xt_connlimit_conn *tmp;
struct list_head *hash = info->data->iphash;
unsigned int i;
- nf_ct_l3proto_module_put(match->family);
+ nf_ct_l3proto_module_put(par->family);
for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i) {
list_for_each_entry_safe(conn, tmp, &hash[i], list) {
kfree(info->data);
}
-static struct xt_match connlimit_reg[] __read_mostly = {
- {
- .name = "connlimit",
- .family = AF_INET,
- .checkentry = connlimit_check,
- .match = connlimit_match,
- .matchsize = sizeof(struct xt_connlimit_info),
- .destroy = connlimit_destroy,
- .me = THIS_MODULE,
- },
- {
- .name = "connlimit",
- .family = AF_INET6,
- .checkentry = connlimit_check,
- .match = connlimit_match,
- .matchsize = sizeof(struct xt_connlimit_info),
- .destroy = connlimit_destroy,
- .me = THIS_MODULE,
- },
+static struct xt_match connlimit_mt_reg __read_mostly = {
+ .name = "connlimit",
+ .revision = 0,
+ .family = NFPROTO_UNSPEC,
+ .checkentry = connlimit_mt_check,
+ .match = connlimit_mt,
+ .matchsize = sizeof(struct xt_connlimit_info),
+ .destroy = connlimit_mt_destroy,
+ .me = THIS_MODULE,
};
-static int __init xt_connlimit_init(void)
+static int __init connlimit_mt_init(void)
{
- return xt_register_matches(connlimit_reg, ARRAY_SIZE(connlimit_reg));
+ return xt_register_match(&connlimit_mt_reg);
}
-static void __exit xt_connlimit_exit(void)
+static void __exit connlimit_mt_exit(void)
{
- xt_unregister_matches(connlimit_reg, ARRAY_SIZE(connlimit_reg));
+ xt_unregister_match(&connlimit_mt_reg);
}
-module_init(xt_connlimit_init);
-module_exit(xt_connlimit_exit);
-MODULE_AUTHOR("Jan Engelhardt <jengelh@gmx.de>");
-MODULE_DESCRIPTION("netfilter xt_connlimit match module");
+module_init(connlimit_mt_init);
+module_exit(connlimit_mt_exit);
+MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>");
+MODULE_DESCRIPTION("Xtables: Number of connections matching");
MODULE_LICENSE("GPL");
MODULE_ALIAS("ipt_connlimit");
MODULE_ALIAS("ip6t_connlimit");