netfilter: conntrack: remove helper hook again
authorFlorian Westphal <fw@strlen.de>
Wed, 9 Jan 2019 16:19:34 +0000 (17:19 +0100)
committerPablo Neira Ayuso <pablo@netfilter.org>
Fri, 18 Jan 2019 14:02:33 +0000 (15:02 +0100)
place them into the confirm one.

Old:
 hook (300): ipv4/6_help() first call helper, then seqadj.
 hook (INT_MAX): confirm

Now:
 hook (INT_MAX): confirm, first call helper, then seqadj, then confirm

Not having the extra call is noticeable in bechmarks.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
net/netfilter/nf_conntrack_proto.c

index 859f5d07a91594eb660559ccd080a2a4e522d31e..2bbc32d939e40600cb2d72e56cda6c4128dd4c05 100644 (file)
@@ -364,55 +364,55 @@ void nf_ct_l4proto_pernet_unregister(struct net *net,
 }
 EXPORT_SYMBOL_GPL(nf_ct_l4proto_pernet_unregister);
 
-static unsigned int ipv4_helper(void *priv,
-                               struct sk_buff *skb,
-                               const struct nf_hook_state *state)
+static unsigned int nf_confirm(struct sk_buff *skb,
+                              unsigned int protoff,
+                              struct nf_conn *ct,
+                              enum ip_conntrack_info ctinfo)
 {
-       struct nf_conn *ct;
-       enum ip_conntrack_info ctinfo;
        const struct nf_conn_help *help;
-       const struct nf_conntrack_helper *helper;
-
-       /* This is where we call the helper: as the packet goes out. */
-       ct = nf_ct_get(skb, &ctinfo);
-       if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-               return NF_ACCEPT;
 
        help = nfct_help(ct);
-       if (!help)
-               return NF_ACCEPT;
+       if (help) {
+               const struct nf_conntrack_helper *helper;
+               int ret;
+
+               /* rcu_read_lock()ed by nf_hook_thresh */
+               helper = rcu_dereference(help->helper);
+               if (helper) {
+                       ret = helper->help(skb,
+                                          protoff,
+                                          ct, ctinfo);
+                       if (ret != NF_ACCEPT)
+                               return ret;
+               }
+       }
 
-       /* rcu_read_lock()ed by nf_hook_thresh */
-       helper = rcu_dereference(help->helper);
-       if (!helper)
-               return NF_ACCEPT;
+       if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
+           !nf_is_loopback_packet(skb)) {
+               if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
+                       NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
+                       return NF_DROP;
+               }
+       }
 
-       return helper->help(skb, skb_network_offset(skb) + ip_hdrlen(skb),
-                           ct, ctinfo);
+       /* We've seen it coming out the other side: confirm it */
+       return nf_conntrack_confirm(skb);
 }
 
 static unsigned int ipv4_confirm(void *priv,
                                 struct sk_buff *skb,
                                 const struct nf_hook_state *state)
 {
-       struct nf_conn *ct;
        enum ip_conntrack_info ctinfo;
+       struct nf_conn *ct;
 
        ct = nf_ct_get(skb, &ctinfo);
        if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-               goto out;
+               return nf_conntrack_confirm(skb);
 
-       /* adjust seqs for loopback traffic only in outgoing direction */
-       if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
-           !nf_is_loopback_packet(skb)) {
-               if (!nf_ct_seq_adjust(skb, ct, ctinfo, ip_hdrlen(skb))) {
-                       NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
-                       return NF_DROP;
-               }
-       }
-out:
-       /* We've seen it coming out the other side: confirm it */
-       return nf_conntrack_confirm(skb);
+       return nf_confirm(skb,
+                         skb_network_offset(skb) + ip_hdrlen(skb),
+                         ct, ctinfo);
 }
 
 static unsigned int ipv4_conntrack_in(void *priv,
@@ -460,24 +460,12 @@ static const struct nf_hook_ops ipv4_conntrack_ops[] = {
                .hooknum        = NF_INET_LOCAL_OUT,
                .priority       = NF_IP_PRI_CONNTRACK,
        },
-       {
-               .hook           = ipv4_helper,
-               .pf             = NFPROTO_IPV4,
-               .hooknum        = NF_INET_POST_ROUTING,
-               .priority       = NF_IP_PRI_CONNTRACK_HELPER,
-       },
        {
                .hook           = ipv4_confirm,
                .pf             = NFPROTO_IPV4,
                .hooknum        = NF_INET_POST_ROUTING,
                .priority       = NF_IP_PRI_CONNTRACK_CONFIRM,
        },
-       {
-               .hook           = ipv4_helper,
-               .pf             = NFPROTO_IPV4,
-               .hooknum        = NF_INET_LOCAL_IN,
-               .priority       = NF_IP_PRI_CONNTRACK_HELPER,
-       },
        {
                .hook           = ipv4_confirm,
                .pf             = NFPROTO_IPV4,
@@ -623,31 +611,21 @@ static unsigned int ipv6_confirm(void *priv,
        struct nf_conn *ct;
        enum ip_conntrack_info ctinfo;
        unsigned char pnum = ipv6_hdr(skb)->nexthdr;
-       int protoff;
        __be16 frag_off;
+       int protoff;
 
        ct = nf_ct_get(skb, &ctinfo);
        if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-               goto out;
+               return nf_conntrack_confirm(skb);
 
        protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
                                   &frag_off);
        if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
                pr_debug("proto header not found\n");
-               goto out;
+               return nf_conntrack_confirm(skb);
        }
 
-       /* adjust seqs for loopback traffic only in outgoing direction */
-       if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
-           !nf_is_loopback_packet(skb)) {
-               if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
-                       NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
-                       return NF_DROP;
-               }
-       }
-out:
-       /* We've seen it coming out the other side: confirm it */
-       return nf_conntrack_confirm(skb);
+       return nf_confirm(skb, protoff, ct, ctinfo);
 }
 
 static unsigned int ipv6_conntrack_in(void *priv,
@@ -664,42 +642,6 @@ static unsigned int ipv6_conntrack_local(void *priv,
        return nf_conntrack_in(skb, state);
 }
 
-static unsigned int ipv6_helper(void *priv,
-                               struct sk_buff *skb,
-                               const struct nf_hook_state *state)
-{
-       struct nf_conn *ct;
-       const struct nf_conn_help *help;
-       const struct nf_conntrack_helper *helper;
-       enum ip_conntrack_info ctinfo;
-       __be16 frag_off;
-       int protoff;
-       u8 nexthdr;
-
-       /* This is where we call the helper: as the packet goes out. */
-       ct = nf_ct_get(skb, &ctinfo);
-       if (!ct || ctinfo == IP_CT_RELATED_REPLY)
-               return NF_ACCEPT;
-
-       help = nfct_help(ct);
-       if (!help)
-               return NF_ACCEPT;
-       /* rcu_read_lock()ed by nf_hook_thresh */
-       helper = rcu_dereference(help->helper);
-       if (!helper)
-               return NF_ACCEPT;
-
-       nexthdr = ipv6_hdr(skb)->nexthdr;
-       protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
-                                  &frag_off);
-       if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
-               pr_debug("proto header not found\n");
-               return NF_ACCEPT;
-       }
-
-       return helper->help(skb, protoff, ct, ctinfo);
-}
-
 static const struct nf_hook_ops ipv6_conntrack_ops[] = {
        {
                .hook           = ipv6_conntrack_in,
@@ -713,24 +655,12 @@ static const struct nf_hook_ops ipv6_conntrack_ops[] = {
                .hooknum        = NF_INET_LOCAL_OUT,
                .priority       = NF_IP6_PRI_CONNTRACK,
        },
-       {
-               .hook           = ipv6_helper,
-               .pf             = NFPROTO_IPV6,
-               .hooknum        = NF_INET_POST_ROUTING,
-               .priority       = NF_IP6_PRI_CONNTRACK_HELPER,
-       },
        {
                .hook           = ipv6_confirm,
                .pf             = NFPROTO_IPV6,
                .hooknum        = NF_INET_POST_ROUTING,
                .priority       = NF_IP6_PRI_LAST,
        },
-       {
-               .hook           = ipv6_helper,
-               .pf             = NFPROTO_IPV6,
-               .hooknum        = NF_INET_LOCAL_IN,
-               .priority       = NF_IP6_PRI_CONNTRACK_HELPER,
-       },
        {
                .hook           = ipv6_confirm,
                .pf             = NFPROTO_IPV6,