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path: root/net/ipv4/netfilter/ip_conntrack_core.c
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Diffstat (limited to 'net/ipv4/netfilter/ip_conntrack_core.c')
-rw-r--r--net/ipv4/netfilter/ip_conntrack_core.c132
1 files changed, 95 insertions, 37 deletions
diff --git a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c
index 07a80b56e8dc..422ab68ee7fb 100644
--- a/net/ipv4/netfilter/ip_conntrack_core.c
+++ b/net/ipv4/netfilter/ip_conntrack_core.c
@@ -50,7 +50,7 @@
#include <linux/netfilter_ipv4/ip_conntrack_core.h>
#include <linux/netfilter_ipv4/listhelp.h>
-#define IP_CONNTRACK_VERSION "2.3"
+#define IP_CONNTRACK_VERSION "2.4"
#if 0
#define DEBUGP printk
@@ -148,16 +148,20 @@ DEFINE_PER_CPU(struct ip_conntrack_stat, ip_conntrack_stat);
static int ip_conntrack_hash_rnd_initted;
static unsigned int ip_conntrack_hash_rnd;
-static u_int32_t
-hash_conntrack(const struct ip_conntrack_tuple *tuple)
+static u_int32_t __hash_conntrack(const struct ip_conntrack_tuple *tuple,
+ unsigned int size, unsigned int rnd)
{
-#if 0
- dump_tuple(tuple);
-#endif
return (jhash_3words(tuple->src.ip,
(tuple->dst.ip ^ tuple->dst.protonum),
(tuple->src.u.all | (tuple->dst.u.all << 16)),
- ip_conntrack_hash_rnd) % ip_conntrack_htable_size);
+ rnd) % size);
+}
+
+static u_int32_t
+hash_conntrack(const struct ip_conntrack_tuple *tuple)
+{
+ return __hash_conntrack(tuple, ip_conntrack_htable_size,
+ ip_conntrack_hash_rnd);
}
int
@@ -1341,14 +1345,13 @@ static int kill_all(struct ip_conntrack *i, void *data)
return 1;
}
-static void free_conntrack_hash(void)
+static void free_conntrack_hash(struct list_head *hash, int vmalloced,int size)
{
- if (ip_conntrack_vmalloc)
- vfree(ip_conntrack_hash);
+ if (vmalloced)
+ vfree(hash);
else
- free_pages((unsigned long)ip_conntrack_hash,
- get_order(sizeof(struct list_head)
- * ip_conntrack_htable_size));
+ free_pages((unsigned long)hash,
+ get_order(sizeof(struct list_head) * size));
}
void ip_conntrack_flush()
@@ -1378,12 +1381,83 @@ void ip_conntrack_cleanup(void)
ip_conntrack_flush();
kmem_cache_destroy(ip_conntrack_cachep);
kmem_cache_destroy(ip_conntrack_expect_cachep);
- free_conntrack_hash();
+ free_conntrack_hash(ip_conntrack_hash, ip_conntrack_vmalloc,
+ ip_conntrack_htable_size);
nf_unregister_sockopt(&so_getorigdst);
}
-static int hashsize;
-module_param(hashsize, int, 0400);
+static struct list_head *alloc_hashtable(int size, int *vmalloced)
+{
+ struct list_head *hash;
+ unsigned int i;
+
+ *vmalloced = 0;
+ hash = (void*)__get_free_pages(GFP_KERNEL,
+ get_order(sizeof(struct list_head)
+ * size));
+ if (!hash) {
+ *vmalloced = 1;
+ printk(KERN_WARNING"ip_conntrack: falling back to vmalloc.\n");
+ hash = vmalloc(sizeof(struct list_head) * size);
+ }
+
+ if (hash)
+ for (i = 0; i < size; i++)
+ INIT_LIST_HEAD(&hash[i]);
+
+ return hash;
+}
+
+int set_hashsize(const char *val, struct kernel_param *kp)
+{
+ int i, bucket, hashsize, vmalloced;
+ int old_vmalloced, old_size;
+ int rnd;
+ struct list_head *hash, *old_hash;
+ struct ip_conntrack_tuple_hash *h;
+
+ /* On boot, we can set this without any fancy locking. */
+ if (!ip_conntrack_htable_size)
+ return param_set_int(val, kp);
+
+ hashsize = simple_strtol(val, NULL, 0);
+ if (!hashsize)
+ return -EINVAL;
+
+ hash = alloc_hashtable(hashsize, &vmalloced);
+ if (!hash)
+ return -ENOMEM;
+
+ /* We have to rehash for the new table anyway, so we also can
+ * use a new random seed */
+ get_random_bytes(&rnd, 4);
+
+ write_lock_bh(&ip_conntrack_lock);
+ for (i = 0; i < ip_conntrack_htable_size; i++) {
+ while (!list_empty(&ip_conntrack_hash[i])) {
+ h = list_entry(ip_conntrack_hash[i].next,
+ struct ip_conntrack_tuple_hash, list);
+ list_del(&h->list);
+ bucket = __hash_conntrack(&h->tuple, hashsize, rnd);
+ list_add_tail(&h->list, &hash[bucket]);
+ }
+ }
+ old_size = ip_conntrack_htable_size;
+ old_vmalloced = ip_conntrack_vmalloc;
+ old_hash = ip_conntrack_hash;
+
+ ip_conntrack_htable_size = hashsize;
+ ip_conntrack_vmalloc = vmalloced;
+ ip_conntrack_hash = hash;
+ ip_conntrack_hash_rnd = rnd;
+ write_unlock_bh(&ip_conntrack_lock);
+
+ free_conntrack_hash(old_hash, old_vmalloced, old_size);
+ return 0;
+}
+
+module_param_call(hashsize, set_hashsize, param_get_uint,
+ &ip_conntrack_htable_size, 0600);
int __init ip_conntrack_init(void)
{
@@ -1392,9 +1466,7 @@ int __init ip_conntrack_init(void)
/* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB
* machine has 256 buckets. >= 1GB machines have 8192 buckets. */
- if (hashsize) {
- ip_conntrack_htable_size = hashsize;
- } else {
+ if (!ip_conntrack_htable_size) {
ip_conntrack_htable_size
= (((num_physpages << PAGE_SHIFT) / 16384)
/ sizeof(struct list_head));
@@ -1416,20 +1488,8 @@ int __init ip_conntrack_init(void)
return ret;
}
- /* AK: the hash table is twice as big than needed because it
- uses list_head. it would be much nicer to caches to use a
- single pointer list head here. */
- ip_conntrack_vmalloc = 0;
- ip_conntrack_hash
- =(void*)__get_free_pages(GFP_KERNEL,
- get_order(sizeof(struct list_head)
- *ip_conntrack_htable_size));
- if (!ip_conntrack_hash) {
- ip_conntrack_vmalloc = 1;
- printk(KERN_WARNING "ip_conntrack: falling back to vmalloc.\n");
- ip_conntrack_hash = vmalloc(sizeof(struct list_head)
- * ip_conntrack_htable_size);
- }
+ ip_conntrack_hash = alloc_hashtable(ip_conntrack_htable_size,
+ &ip_conntrack_vmalloc);
if (!ip_conntrack_hash) {
printk(KERN_ERR "Unable to create ip_conntrack_hash\n");
goto err_unreg_sockopt;
@@ -1461,9 +1521,6 @@ int __init ip_conntrack_init(void)
ip_ct_protos[IPPROTO_ICMP] = &ip_conntrack_protocol_icmp;
write_unlock_bh(&ip_conntrack_lock);
- for (i = 0; i < ip_conntrack_htable_size; i++)
- INIT_LIST_HEAD(&ip_conntrack_hash[i]);
-
/* For use by ipt_REJECT */
ip_ct_attach = ip_conntrack_attach;
@@ -1478,7 +1535,8 @@ int __init ip_conntrack_init(void)
err_free_conntrack_slab:
kmem_cache_destroy(ip_conntrack_cachep);
err_free_hash:
- free_conntrack_hash();
+ free_conntrack_hash(ip_conntrack_hash, ip_conntrack_vmalloc,
+ ip_conntrack_htable_size);
err_unreg_sockopt:
nf_unregister_sockopt(&so_getorigdst);