[NETFILTER] nf_conntrack: clean up to reduce size of 'struct nf_conn'

This patch moves all helper related data fields of 'struct nf_conn'
into a separate structure 'struct nf_conn_help'.  This new structure
is only present in conntrack entries for which we actually have a
helper loaded.

Also, this patch cleans up the nf_conntrack 'features' mechanism to
resemble what the original idea was: Just glue the feature-specific
data structures at the end of 'struct nf_conn', and explicitly
re-calculate the pointer to it when needed rather than keeping
pointers around.

Saves 20 bytes per conntrack on my x86_64 box. A non-helped conntrack
is 276 bytes. We still need to save another 20 bytes in order to fit
into to target of 256bytes.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 148 insertions, 138 deletions

diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index 6d075ca16e6e..2743c156caa0 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -67,6 +67,18 @@ do {									\
 
 struct nf_conntrack_helper;
 
+/* nf_conn feature for connections that have a helper */
+struct nf_conn_help {
+        /* Helper. if any */
+        struct nf_conntrack_helper *helper;
+
+        union nf_conntrack_help help;
+
+        /* Current number of expected connections */
+        unsigned int expecting;
+};
+
+
 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
 struct nf_conn
 {
@@ -81,6 +93,9 @@ struct nf_conn
         /* Have we seen traffic both ways yet? (bitset) */
         unsigned long status;
 
+        /* If we were expected by an expectation, this will be it */
+        struct nf_conn *master;
+
         /* Timer function; drops refcnt when it goes off. */
         struct timer_list timeout;
 
@@ -88,38 +103,22 @@ struct nf_conn
         /* Accounting Information (same cache line as other written members) */
         struct ip_conntrack_counter counters[IP_CT_DIR_MAX];
 #endif
-        /* If we were expected by an expectation, this will be it */
-        struct nf_conn *master;
-        
-        /* Current number of expected connections */
-        unsigned int expecting;
 
         /* Unique ID that identifies this conntrack*/
         unsigned int id;
 
-        /* Helper. if any */
-        struct nf_conntrack_helper *helper;
-
         /* features - nat, helper, ... used by allocating system */
         u_int32_t features;
 
-        /* Storage reserved for other modules: */
-
-        union nf_conntrack_proto proto;
-
 #if defined(CONFIG_NF_CONNTRACK_MARK)
         u_int32_t mark;
 #endif
 
-        /* These members are dynamically allocated. */
-
-        union nf_conntrack_help *help;
+        /* Storage reserved for other modules: */
+        union nf_conntrack_proto proto;
 
-        /* Layer 3 dependent members. (ex: NAT) */
-        union {
-                struct nf_conntrack_ipv4 *ipv4;
-        } l3proto;
-        void *data[0];
+        /* features dynamically at the end: helper, nat (both optional) */
+        char data[0];
 };
 
 struct nf_conntrack_expect
@@ -373,10 +372,23 @@ nf_conntrack_expect_event(enum ip_conntrack_expect_events event,
 #define NF_CT_F_NUM     4
 
 extern int
-nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size,
-                            int (*init_conntrack)(struct nf_conn *, u_int32_t));
+nf_conntrack_register_cache(u_int32_t features, const char *name, size_t size);
 extern void
 nf_conntrack_unregister_cache(u_int32_t features);
 
+/* valid combinations:
+ * basic: nf_conn, nf_conn .. nf_conn_help
+ * nat: nf_conn .. nf_conn_nat, nf_conn .. nf_conn_nat, nf_conn help
+ */
+static inline struct nf_conn_help *nfct_help(const struct nf_conn *ct)
+{
+        unsigned int offset = sizeof(struct nf_conn);
+
+        if (!(ct->features & NF_CT_F_HELP))
+                return NULL;
+
+        return (struct nf_conn_help *) ((void *)ct + offset);
+}
+
 #endif /* __KERNEL__ */
 #endif /* _NF_CONNTRACK_H */
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index 6c8624a54933..cb9c661f3f33 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
@@ -141,19 +141,21 @@ static unsigned int ipv4_conntrack_help(unsigned int hooknum,
 {
         struct nf_conn *ct;
         enum ip_conntrack_info ctinfo;
+        struct nf_conn_help *help;
 
         /* This is where we call the helper: as the packet goes out. */
         ct = nf_ct_get(*pskb, &ctinfo);
-        if (ct && ct->helper) {
-                unsigned int ret;
-                ret = ct->helper->help(pskb,
-                                       (*pskb)->nh.raw - (*pskb)->data
-                                                       + (*pskb)->nh.iph->ihl*4,
-                                       ct, ctinfo);
-                if (ret != NF_ACCEPT)
-                        return ret;
-        }
-        return NF_ACCEPT;
+        if (!ct)
+                return NF_ACCEPT;
+
+        help = nfct_help(ct);
+        if (!help || !help->helper)
+                return NF_ACCEPT;
+
+        return help->helper->help(pskb,
+                               (*pskb)->nh.raw - (*pskb)->data
+                                               + (*pskb)->nh.iph->ihl*4,
+                               ct, ctinfo);
 }
 
 static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index ac702a29dd16..ac35f9526368 100644
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -179,31 +179,36 @@ static unsigned int ipv6_confirm(unsigned int hooknum,
                                  int (*okfn)(struct sk_buff *))
 {
         struct nf_conn *ct;
+        struct nf_conn_help *help;
         enum ip_conntrack_info ctinfo;
+        unsigned int ret, protoff;
+        unsigned int extoff = (u8*)((*pskb)->nh.ipv6h + 1)
+                              - (*pskb)->data;
+        unsigned char pnum = (*pskb)->nh.ipv6h->nexthdr;
+
 
         /* This is where we call the helper: as the packet goes out. */
         ct = nf_ct_get(*pskb, &ctinfo);
-        if (ct && ct->helper) {
-                unsigned int ret, protoff;
-                unsigned int extoff = (u8*)((*pskb)->nh.ipv6h + 1)
-                                      - (*pskb)->data;
-                unsigned char pnum = (*pskb)->nh.ipv6h->nexthdr;
-
-                protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
-                                                 (*pskb)->len - extoff);
-                if (protoff < 0 || protoff > (*pskb)->len ||
-                    pnum == NEXTHDR_FRAGMENT) {
-                        DEBUGP("proto header not found\n");
-                        return NF_ACCEPT;
-                }
+        if (!ct)
+                goto out;
 
-                ret = ct->helper->help(pskb, protoff, ct, ctinfo);
-                if (ret != NF_ACCEPT)
-                        return ret;
+        help = nfct_help(ct);
+        if (!help || !help->helper)
+                goto out;
+
+        protoff = nf_ct_ipv6_skip_exthdr(*pskb, extoff, &pnum,
+                                         (*pskb)->len - extoff);
+        if (protoff < 0 || protoff > (*pskb)->len ||
+            pnum == NEXTHDR_FRAGMENT) {
+                DEBUGP("proto header not found\n");
+                return NF_ACCEPT;
         }
 
+        ret = help->helper->help(pskb, protoff, ct, ctinfo);
+        if (ret != NF_ACCEPT)
+                return ret;
+out:
         /* We've seen it coming out the other side: confirm it */
-
         return nf_conntrack_confirm(pskb);
 }
 
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index d622ddf08bb0..dc68d0022218 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -3,7 +3,7 @@
    extension. */
 
 /* (C) 1999-2001 Paul `Rusty' Russell
- * (C) 2002-2005 Netfilter Core Team <coreteam@netfilter.org>
+ * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
  * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
  *
  * This program is free software; you can redistribute it and/or modify
@@ -20,6 +20,9 @@
  *      - generalize L3 protocol denendent part.
  * 23 Mar 2004: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
  *      - add support various size of conntrack structures.
+ * 26 Jan 2006: Harald Welte <laforge@netfilter.org>
+ *      - restructure nf_conn (introduce nf_conn_help)
+ *      - redesign 'features' how they were originally intended
  *
  * Derived from net/ipv4/netfilter/ip_conntrack_core.c
  */
@@ -55,7 +58,7 @@
 #include <net/netfilter/nf_conntrack_core.h>
 #include <linux/netfilter_ipv4/listhelp.h>
 
-#define NF_CONNTRACK_VERSION    "0.4.1"
+#define NF_CONNTRACK_VERSION    "0.5.0"
 
 #if 0
 #define DEBUGP printk
@@ -259,21 +262,8 @@ static inline u_int32_t hash_conntrack(const struct nf_conntrack_tuple *tuple)
                                 nf_conntrack_hash_rnd);
 }
 
-/* Initialize "struct nf_conn" which has spaces for helper */
-static int
-init_conntrack_for_helper(struct nf_conn *conntrack, u_int32_t features)
-{
-
-        conntrack->help = (union nf_conntrack_help *)
-                (((unsigned long)conntrack->data
-                  + (__alignof__(union nf_conntrack_help) - 1))
-                 & (~((unsigned long)(__alignof__(union nf_conntrack_help) -1))));
-        return 0;
-}
-
 int nf_conntrack_register_cache(u_int32_t features, const char *name,
-                                size_t size,
-                                int (*init)(struct nf_conn *, u_int32_t))
+                                size_t size)
 {
         int ret = 0;
         char *cache_name;
@@ -296,8 +286,7 @@ int nf_conntrack_register_cache(u_int32_t features, const char *name,
                 DEBUGP("nf_conntrack_register_cache: already resisterd.\n");
                 if ((!strncmp(nf_ct_cache[features].name, name,
                               NF_CT_FEATURES_NAMELEN))
-                    && nf_ct_cache[features].size == size
-                    && nf_ct_cache[features].init_conntrack == init) {
+                    && nf_ct_cache[features].size == size) {
                         DEBUGP("nf_conntrack_register_cache: reusing.\n");
                         nf_ct_cache[features].use++;
                         ret = 0;
@@ -340,7 +329,6 @@ int nf_conntrack_register_cache(u_int32_t features, const char *name,
         write_lock_bh(&nf_ct_cache_lock);
         nf_ct_cache[features].use = 1;
         nf_ct_cache[features].size = size;
-        nf_ct_cache[features].init_conntrack = init;
         nf_ct_cache[features].cachep = cachep;
         nf_ct_cache[features].name = cache_name;
         write_unlock_bh(&nf_ct_cache_lock);
@@ -377,7 +365,6 @@ void nf_conntrack_unregister_cache(u_int32_t features)
         name = nf_ct_cache[features].name;
         nf_ct_cache[features].cachep = NULL;
         nf_ct_cache[features].name = NULL;
-        nf_ct_cache[features].init_conntrack = NULL;
         nf_ct_cache[features].size = 0;
         write_unlock_bh(&nf_ct_cache_lock);
 
@@ -432,11 +419,15 @@ nf_ct_invert_tuple(struct nf_conntrack_tuple *inverse,
 /* nf_conntrack_expect helper functions */
 void nf_ct_unlink_expect(struct nf_conntrack_expect *exp)
 {
+        struct nf_conn_help *master_help = nfct_help(exp->master);
+
+        NF_CT_ASSERT(master_help);
         ASSERT_WRITE_LOCK(&nf_conntrack_lock);
         NF_CT_ASSERT(!timer_pending(&exp->timeout));
+
         list_del(&exp->list);
         NF_CT_STAT_INC(expect_delete);
-        exp->master->expecting--;
+        master_help->expecting--;
         nf_conntrack_expect_put(exp);
 }
 
@@ -508,9 +499,10 @@ find_expectation(const struct nf_conntrack_tuple *tuple)
 void nf_ct_remove_expectations(struct nf_conn *ct)
 {
         struct nf_conntrack_expect *i, *tmp;
+        struct nf_conn_help *help = nfct_help(ct);
 
         /* Optimization: most connection never expect any others. */
-        if (ct->expecting == 0)
+        if (!help || help->expecting == 0)
                 return;
 
         list_for_each_entry_safe(i, tmp, &nf_conntrack_expect_list, list) {
@@ -713,6 +705,7 @@ __nf_conntrack_confirm(struct sk_buff **pskb)
                           conntrack_tuple_cmp,
                           struct nf_conntrack_tuple_hash *,
                           &ct->tuplehash[IP_CT_DIR_REPLY].tuple, NULL)) {
+                struct nf_conn_help *help;
                 /* Remove from unconfirmed list */
                 list_del(&ct->tuplehash[IP_CT_DIR_ORIGINAL].list);
 
@@ -726,7 +719,8 @@ __nf_conntrack_confirm(struct sk_buff **pskb)
                 set_bit(IPS_CONFIRMED_BIT, &ct->status);
                 NF_CT_STAT_INC(insert);
                 write_unlock_bh(&nf_conntrack_lock);
-                if (ct->helper)
+                help = nfct_help(ct);
+                if (help && help->helper)
                         nf_conntrack_event_cache(IPCT_HELPER, *pskb);
 #ifdef CONFIG_NF_NAT_NEEDED
                 if (test_bit(IPS_SRC_NAT_DONE_BIT, &ct->status) ||
@@ -842,8 +836,9 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
 {
         struct nf_conn *conntrack = NULL;
         u_int32_t features = 0;
+        struct nf_conntrack_helper *helper;
 
-        if (!nf_conntrack_hash_rnd_initted) {
+        if (unlikely(!nf_conntrack_hash_rnd_initted)) {
                 get_random_bytes(&nf_conntrack_hash_rnd, 4);
                 nf_conntrack_hash_rnd_initted = 1;
         }
@@ -863,8 +858,11 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
 
         /*  find features needed by this conntrack. */
         features = l3proto->get_features(orig);
+
+        /* FIXME: protect helper list per RCU */
         read_lock_bh(&nf_conntrack_lock);
-        if (__nf_ct_helper_find(repl) != NULL)
+        helper = __nf_ct_helper_find(repl);
+        if (helper)
                 features |= NF_CT_F_HELP;
         read_unlock_bh(&nf_conntrack_lock);
 
@@ -872,7 +870,7 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
 
         read_lock_bh(&nf_ct_cache_lock);
 
-        if (!nf_ct_cache[features].use) {
+        if (unlikely(!nf_ct_cache[features].use)) {
                 DEBUGP("nf_conntrack_alloc: not supported features = 0x%x\n",
                         features);
                 goto out;
@@ -886,12 +884,10 @@ __nf_conntrack_alloc(const struct nf_conntrack_tuple *orig,
 
         memset(conntrack, 0, nf_ct_cache[features].size);
         conntrack->features = features;
-        if (nf_ct_cache[features].init_conntrack &&
-            nf_ct_cache[features].init_conntrack(conntrack, features) < 0) {
-                DEBUGP("nf_conntrack_alloc: failed to init\n");
-                kmem_cache_free(nf_ct_cache[features].cachep, conntrack);
-                conntrack = NULL;
-                goto out;
+        if (helper) {
+                struct nf_conn_help *help = nfct_help(conntrack);
+                NF_CT_ASSERT(help);
+                help->helper = helper;
         }
 
         atomic_set(&conntrack->ct_general.use, 1);
@@ -972,11 +968,8 @@ init_conntrack(const struct nf_conntrack_tuple *tuple,
 #endif
                 nf_conntrack_get(&conntrack->master->ct_general);
                 NF_CT_STAT_INC(expect_new);
-        } else {
-                conntrack->helper = __nf_ct_helper_find(&repl_tuple);
-
+        } else
                 NF_CT_STAT_INC(new);
-        }
 
         /* Overload tuple linked list to put us in unconfirmed list. */
         list_add(&conntrack->tuplehash[IP_CT_DIR_ORIGINAL].list, &unconfirmed);
@@ -1206,14 +1199,16 @@ void nf_conntrack_expect_put(struct nf_conntrack_expect *exp)
 
 static void nf_conntrack_expect_insert(struct nf_conntrack_expect *exp)
 {
+        struct nf_conn_help *master_help = nfct_help(exp->master);
+
         atomic_inc(&exp->use);
-        exp->master->expecting++;
+        master_help->expecting++;
         list_add(&exp->list, &nf_conntrack_expect_list);
 
         init_timer(&exp->timeout);
         exp->timeout.data = (unsigned long)exp;
         exp->timeout.function = expectation_timed_out;
-        exp->timeout.expires = jiffies + exp->master->helper->timeout * HZ;
+        exp->timeout.expires = jiffies + master_help->helper->timeout * HZ;
         add_timer(&exp->timeout);
 
         exp->id = ++nf_conntrack_expect_next_id;
@@ -1239,10 +1234,12 @@ static void evict_oldest_expect(struct nf_conn *master)
 
 static inline int refresh_timer(struct nf_conntrack_expect *i)
 {
+        struct nf_conn_help *master_help = nfct_help(i->master);
+
         if (!del_timer(&i->timeout))
                 return 0;
 
-        i->timeout.expires = jiffies + i->master->helper->timeout*HZ;
+        i->timeout.expires = jiffies + master_help->helper->timeout*HZ;
         add_timer(&i->timeout);
         return 1;
 }
@@ -1251,8 +1248,11 @@ int nf_conntrack_expect_related(struct nf_conntrack_expect *expect)
 {
         struct nf_conntrack_expect *i;
         struct nf_conn *master = expect->master;
+        struct nf_conn_help *master_help = nfct_help(master);
         int ret;
 
+        NF_CT_ASSERT(master_help);
+
         DEBUGP("nf_conntrack_expect_related %p\n", related_to);
         DEBUGP("tuple: "); NF_CT_DUMP_TUPLE(&expect->tuple);
         DEBUGP("mask:  "); NF_CT_DUMP_TUPLE(&expect->mask);
@@ -1271,8 +1271,8 @@ int nf_conntrack_expect_related(struct nf_conntrack_expect *expect)
                 }
         }
         /* Will be over limit? */
-        if (master->helper->max_expected && 
-            master->expecting >= master->helper->max_expected)
+        if (master_help->helper->max_expected &&
+            master_help->expecting >= master_help->helper->max_expected)
                 evict_oldest_expect(master);
 
         nf_conntrack_expect_insert(expect);
@@ -1283,24 +1283,6 @@ out:
         return ret;
 }
 
-/* Alter reply tuple (maybe alter helper).  This is for NAT, and is
-   implicitly racy: see __nf_conntrack_confirm */
-void nf_conntrack_alter_reply(struct nf_conn *conntrack,
-                              const struct nf_conntrack_tuple *newreply)
-{
-        write_lock_bh(&nf_conntrack_lock);
-        /* Should be unconfirmed, so not in hash table yet */
-        NF_CT_ASSERT(!nf_ct_is_confirmed(conntrack));
-
-        DEBUGP("Altering reply tuple of %p to ", conntrack);
-        NF_CT_DUMP_TUPLE(newreply);
-
-        conntrack->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;
-        if (!conntrack->master && conntrack->expecting == 0)
-                conntrack->helper = __nf_ct_helper_find(newreply);
-        write_unlock_bh(&nf_conntrack_lock);
-}
-
 int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 {
         int ret;
@@ -1308,9 +1290,8 @@ int nf_conntrack_helper_register(struct nf_conntrack_helper *me)
 
         ret = nf_conntrack_register_cache(NF_CT_F_HELP, "nf_conntrack:help",
                                           sizeof(struct nf_conn)
-                                          + sizeof(union nf_conntrack_help)
-                                          + __alignof__(union nf_conntrack_help),
-                                          init_conntrack_for_helper);
+                                          + sizeof(struct nf_conn_help)
+                                          + __alignof__(struct nf_conn_help));
         if (ret < 0) {
                 printk(KERN_ERR "nf_conntrack_helper_reigster: Unable to create slab cache for conntracks\n");
                 return ret;
@@ -1338,9 +1319,12 @@ __nf_conntrack_helper_find_byname(const char *name)
 static inline int unhelp(struct nf_conntrack_tuple_hash *i,
                          const struct nf_conntrack_helper *me)
 {
-        if (nf_ct_tuplehash_to_ctrack(i)->helper == me) {
-                nf_conntrack_event(IPCT_HELPER, nf_ct_tuplehash_to_ctrack(i));
-                nf_ct_tuplehash_to_ctrack(i)->helper = NULL;
+        struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(i);
+        struct nf_conn_help *help = nfct_help(ct);
+
+        if (help && help->helper == me) {
+                nf_conntrack_event(IPCT_HELPER, ct);
+                help->helper = NULL;
         }
         return 0;
 }
@@ -1356,7 +1340,8 @@ void nf_conntrack_helper_unregister(struct nf_conntrack_helper *me)
 
         /* Get rid of expectations */
         list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list, list) {
-                if (exp->master->helper == me && del_timer(&exp->timeout)) {
+                struct nf_conn_help *help = nfct_help(exp->master);
+                if (help->helper == me && del_timer(&exp->timeout)) {
                         nf_ct_unlink_expect(exp);
                         nf_conntrack_expect_put(exp);
                 }
@@ -1697,7 +1682,7 @@ int __init nf_conntrack_init(void)
         }
 
         ret = nf_conntrack_register_cache(NF_CT_F_BASIC, "nf_conntrack:basic",
-                                          sizeof(struct nf_conn), NULL);
+                                          sizeof(struct nf_conn));
         if (ret < 0) {
                 printk(KERN_ERR "Unable to create nf_conn slab cache\n");
                 goto err_free_hash;
diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c
index 6f210f399762..cd191b0d4ac7 100644
--- a/net/netfilter/nf_conntrack_ftp.c
+++ b/net/netfilter/nf_conntrack_ftp.c
@@ -440,7 +440,7 @@ static int help(struct sk_buff **pskb,
         u32 seq;
         int dir = CTINFO2DIR(ctinfo);
         unsigned int matchlen, matchoff;
-        struct ip_ct_ftp_master *ct_ftp_info = &ct->help->ct_ftp_info;
+        struct ip_ct_ftp_master *ct_ftp_info = &nfct_help(ct)->help.ct_ftp_info;
         struct nf_conntrack_expect *exp;
         struct nf_conntrack_man cmd = {};
 
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 9ff3463037e1..aef3cb41131f 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -2,7 +2,7 @@
  * protocol helpers and general trouble making from userspace.
  *
  * (C) 2001 by Jay Schulist <jschlst@samba.org>
- * (C) 2002-2005 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
  * (C) 2005 by Pablo Neira Ayuso <pablo@eurodev.net>
  *
@@ -44,7 +44,7 @@
 
 MODULE_LICENSE("GPL");
 
-static char __initdata version[] = "0.92";
+static char __initdata version[] = "0.93";
 
 #if 0
 #define DEBUGP printk
@@ -165,15 +165,16 @@ static inline int
 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
 {
         struct nfattr *nest_helper;
+        const struct nf_conn_help *help = nfct_help(ct);
 
-        if (!ct->helper)
+        if (!help || !help->helper)
                 return 0;
                 
         nest_helper = NFA_NEST(skb, CTA_HELP);
-        NFA_PUT(skb, CTA_HELP_NAME, strlen(ct->helper->name), ct->helper->name);
+        NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
 
-        if (ct->helper->to_nfattr)
-                ct->helper->to_nfattr(skb, ct);
+        if (help->helper->to_nfattr)
+                help->helper->to_nfattr(skb, ct);
 
         NFA_NEST_END(skb, nest_helper);
 
@@ -903,11 +904,17 @@ static inline int
 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
 {
         struct nf_conntrack_helper *helper;
+        struct nf_conn_help *help = nfct_help(ct);
         char *helpname;
         int err;
 
         DEBUGP("entered %s\n", __FUNCTION__);
 
+        if (!help) {
+                /* FIXME: we need to reallocate and rehash */
+                return -EBUSY;
+        }
+
         /* don't change helper of sibling connections */
         if (ct->master)
                 return -EINVAL;
@@ -924,18 +931,18 @@ ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
                         return -EINVAL;
         }
 
-        if (ct->helper) {
+        if (help->helper) {
                 if (!helper) {
                         /* we had a helper before ... */
                         nf_ct_remove_expectations(ct);
-                        ct->helper = NULL;
+                        help->helper = NULL;
                 } else {
                         /* need to zero data of old helper */
-                        memset(&ct->help, 0, sizeof(ct->help));
+                        memset(&help->help, 0, sizeof(help->help));
                 }
         }
         
-        ct->helper = helper;
+        help->helper = helper;
 
         return 0;
 }
@@ -1050,14 +1057,9 @@ ctnetlink_create_conntrack(struct nfattr *cda[],
                 ct->mark = ntohl(*(u_int32_t *)NFA_DATA(cda[CTA_MARK-1]));
 #endif
 
-        ct->helper = nf_ct_helper_find_get(rtuple);
-
         add_timer(&ct->timeout);
         nf_conntrack_hash_insert(ct);
 
-        if (ct->helper)
-                nf_ct_helper_put(ct->helper);
-
         DEBUGP("conntrack with id %u inserted\n", ct->id);
         return 0;
 
@@ -1417,7 +1419,8 @@ ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
                 }
                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
                                          list) {
-                        if (exp->master->helper == h 
+                        struct nf_conn_help *m_help = nfct_help(exp->master);
+                        if (m_help->helper == h
                             && del_timer(&exp->timeout)) {
                                 nf_ct_unlink_expect(exp);
                                 nf_conntrack_expect_put(exp);
@@ -1452,6 +1455,7 @@ ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
         struct nf_conntrack_tuple_hash *h = NULL;
         struct nf_conntrack_expect *exp;
         struct nf_conn *ct;
+        struct nf_conn_help *help;
         int err = 0;
 
         DEBUGP("entered %s\n", __FUNCTION__);
@@ -1472,8 +1476,9 @@ ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
         if (!h)
                 return -ENOENT;
         ct = nf_ct_tuplehash_to_ctrack(h);
+        help = nfct_help(ct);
 
-        if (!ct->helper) {
+        if (!help || !help->helper) {
                 /* such conntrack hasn't got any helper, abort */
                 err = -EINVAL;
                 goto out;
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 617599aeeead..290d5a0c559b 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -839,7 +839,6 @@ EXPORT_SYMBOL(nf_conntrack_l3proto_unregister);
 EXPORT_SYMBOL(nf_conntrack_protocol_register);
 EXPORT_SYMBOL(nf_conntrack_protocol_unregister);
 EXPORT_SYMBOL(nf_ct_invert_tuplepr);
-EXPORT_SYMBOL(nf_conntrack_alter_reply);
 EXPORT_SYMBOL(nf_conntrack_destroyed);
 EXPORT_SYMBOL(need_conntrack);
 EXPORT_SYMBOL(nf_conntrack_helper_register);
diff --git a/net/netfilter/xt_helper.c b/net/netfilter/xt_helper.c
index 38b6715e1db4..0ddb32363d06 100644
--- a/net/netfilter/xt_helper.c
+++ b/net/netfilter/xt_helper.c
@@ -96,6 +96,7 @@ match(const struct sk_buff *skb,
 {
         const struct xt_helper_info *info = matchinfo;
         struct nf_conn *ct;
+        struct nf_conn_help *master_help;
         enum ip_conntrack_info ctinfo;
         int ret = info->invert;
         
@@ -111,7 +112,8 @@ match(const struct sk_buff *skb,
         }
 
         read_lock_bh(&nf_conntrack_lock);
-        if (!ct->master->helper) {
+        master_help = nfct_help(ct->master);
+        if (!master_help || !master_help->helper) {
                 DEBUGP("xt_helper: master ct %p has no helper\n", 
                         exp->expectant);
                 goto out_unlock;
@@ -123,8 +125,8 @@ match(const struct sk_buff *skb,
         if (info->name[0] == '\0')
                 ret ^= 1;
         else
-                ret ^= !strncmp(ct->master->helper->name, info->name, 
-                                strlen(ct->master->helper->name));
+                ret ^= !strncmp(master_help->helper->name, info->name,
+                                strlen(master_help->helper->name));
 out_unlock:
         read_unlock_bh(&nf_conntrack_lock);
         return ret;