From 1f55236bd8dde69d1860a30c50793fb28d8405ae Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 14 May 2018 23:46:53 +0200 Subject: netfilter: nf_nat: move common nat code to nat core Copy-pasted, both l3 helpers almost use same code here. Split out the common part into an 'inet' helper. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_nat_core.h | 7 ++++ net/ipv4/netfilter/nf_nat_l3proto_ipv4.c | 55 +------------------------ net/ipv6/netfilter/nf_nat_l3proto_ipv6.c | 48 +--------------------- net/netfilter/nf_nat_core.c | 70 ++++++++++++++++++++++++++++++++ 4 files changed, 81 insertions(+), 99 deletions(-) diff --git a/include/net/netfilter/nf_nat_core.h b/include/net/netfilter/nf_nat_core.h index 235bd0e9a5aa..0d84dd29108d 100644 --- a/include/net/netfilter/nf_nat_core.h +++ b/include/net/netfilter/nf_nat_core.h @@ -11,6 +11,13 @@ unsigned int nf_nat_packet(struct nf_conn *ct, enum ip_conntrack_info ctinfo, unsigned int hooknum, struct sk_buff *skb); +unsigned int +nf_nat_inet_fn(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state, + unsigned int (*do_chain)(void *priv, + struct sk_buff *skb, + const struct nf_hook_state *state)); + int nf_xfrm_me_harder(struct net *net, struct sk_buff *skb, unsigned int family); static inline int nf_nat_initialized(struct nf_conn *ct, diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c index 325e02956bf5..29b5aceac66d 100644 --- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c +++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c @@ -250,24 +250,12 @@ nf_nat_ipv4_fn(void *priv, struct sk_buff *skb, { struct nf_conn *ct; enum ip_conntrack_info ctinfo; - struct nf_conn_nat *nat; - /* maniptype == SRC for postrouting. */ - enum nf_nat_manip_type maniptype = HOOK2MANIP(state->hook); ct = nf_ct_get(skb, &ctinfo); - /* Can't track? It's not due to stress, or conntrack would - * have dropped it. Hence it's the user's responsibilty to - * packet filter it out, or implement conntrack/NAT for that - * protocol. 8) --RR - */ if (!ct) return NF_ACCEPT; - nat = nfct_nat(ct); - - switch (ctinfo) { - case IP_CT_RELATED: - case IP_CT_RELATED_REPLY: + if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_REPLY) { if (ip_hdr(skb)->protocol == IPPROTO_ICMP) { if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, state->hook)) @@ -275,48 +263,9 @@ nf_nat_ipv4_fn(void *priv, struct sk_buff *skb, else return NF_ACCEPT; } - /* Only ICMPs can be IP_CT_IS_REPLY: */ - /* fall through */ - case IP_CT_NEW: - /* Seen it before? This can happen for loopback, retrans, - * or local packets. - */ - if (!nf_nat_initialized(ct, maniptype)) { - unsigned int ret; - - ret = do_chain(priv, skb, state); - if (ret != NF_ACCEPT) - return ret; - - if (nf_nat_initialized(ct, HOOK2MANIP(state->hook))) - break; - - ret = nf_nat_alloc_null_binding(ct, state->hook); - if (ret != NF_ACCEPT) - return ret; - } else { - pr_debug("Already setup manip %s for ct %p\n", - maniptype == NF_NAT_MANIP_SRC ? "SRC" : "DST", - ct); - if (nf_nat_oif_changed(state->hook, ctinfo, nat, - state->out)) - goto oif_changed; - } - break; - - default: - /* ESTABLISHED */ - WARN_ON(ctinfo != IP_CT_ESTABLISHED && - ctinfo != IP_CT_ESTABLISHED_REPLY); - if (nf_nat_oif_changed(state->hook, ctinfo, nat, state->out)) - goto oif_changed; } - return nf_nat_packet(ct, ctinfo, state->hook, skb); - -oif_changed: - nf_ct_kill_acct(ct, ctinfo, skb); - return NF_DROP; + return nf_nat_inet_fn(priv, skb, state, do_chain); } EXPORT_SYMBOL_GPL(nf_nat_ipv4_fn); diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c index f1582b6f9588..3ec228984f82 100644 --- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c +++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c @@ -261,8 +261,6 @@ nf_nat_ipv6_fn(void *priv, struct sk_buff *skb, { struct nf_conn *ct; enum ip_conntrack_info ctinfo; - struct nf_conn_nat *nat; - enum nf_nat_manip_type maniptype = HOOK2MANIP(state->hook); __be16 frag_off; int hdrlen; u8 nexthdr; @@ -276,11 +274,7 @@ nf_nat_ipv6_fn(void *priv, struct sk_buff *skb, if (!ct) return NF_ACCEPT; - nat = nfct_nat(ct); - - switch (ctinfo) { - case IP_CT_RELATED: - case IP_CT_RELATED_REPLY: + if (ctinfo == IP_CT_RELATED || ctinfo == IP_CT_RELATED_REPLY) { nexthdr = ipv6_hdr(skb)->nexthdr; hdrlen = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, &frag_off); @@ -293,47 +287,9 @@ nf_nat_ipv6_fn(void *priv, struct sk_buff *skb, else return NF_ACCEPT; } - /* Only ICMPs can be IP_CT_IS_REPLY: */ - /* fall through */ - case IP_CT_NEW: - /* Seen it before? This can happen for loopback, retrans, - * or local packets. - */ - if (!nf_nat_initialized(ct, maniptype)) { - unsigned int ret; - - ret = do_chain(priv, skb, state); - if (ret != NF_ACCEPT) - return ret; - - if (nf_nat_initialized(ct, HOOK2MANIP(state->hook))) - break; - - ret = nf_nat_alloc_null_binding(ct, state->hook); - if (ret != NF_ACCEPT) - return ret; - } else { - pr_debug("Already setup manip %s for ct %p\n", - maniptype == NF_NAT_MANIP_SRC ? "SRC" : "DST", - ct); - if (nf_nat_oif_changed(state->hook, ctinfo, nat, state->out)) - goto oif_changed; - } - break; - - default: - /* ESTABLISHED */ - WARN_ON(ctinfo != IP_CT_ESTABLISHED && - ctinfo != IP_CT_ESTABLISHED_REPLY); - if (nf_nat_oif_changed(state->hook, ctinfo, nat, state->out)) - goto oif_changed; } - return nf_nat_packet(ct, ctinfo, state->hook, skb); - -oif_changed: - nf_ct_kill_acct(ct, ctinfo, skb); - return NF_DROP; + return nf_nat_inet_fn(priv, skb, state, do_chain); } EXPORT_SYMBOL_GPL(nf_nat_ipv6_fn); diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index 37b3c9913b08..0cd503aacbf0 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -513,6 +513,76 @@ unsigned int nf_nat_packet(struct nf_conn *ct, } EXPORT_SYMBOL_GPL(nf_nat_packet); +unsigned int +nf_nat_inet_fn(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state, + unsigned int (*do_chain)(void *priv, + struct sk_buff *skb, + const struct nf_hook_state *state)) +{ + struct nf_conn *ct; + enum ip_conntrack_info ctinfo; + struct nf_conn_nat *nat; + /* maniptype == SRC for postrouting. */ + enum nf_nat_manip_type maniptype = HOOK2MANIP(state->hook); + + ct = nf_ct_get(skb, &ctinfo); + /* Can't track? It's not due to stress, or conntrack would + * have dropped it. Hence it's the user's responsibilty to + * packet filter it out, or implement conntrack/NAT for that + * protocol. 8) --RR + */ + if (!ct) + return NF_ACCEPT; + + nat = nfct_nat(ct); + + switch (ctinfo) { + case IP_CT_RELATED: + case IP_CT_RELATED_REPLY: + /* Only ICMPs can be IP_CT_IS_REPLY. Fallthrough */ + case IP_CT_NEW: + /* Seen it before? This can happen for loopback, retrans, + * or local packets. + */ + if (!nf_nat_initialized(ct, maniptype)) { + unsigned int ret; + + ret = do_chain(priv, skb, state); + if (ret != NF_ACCEPT) + return ret; + + if (nf_nat_initialized(ct, HOOK2MANIP(state->hook))) + break; + + ret = nf_nat_alloc_null_binding(ct, state->hook); + if (ret != NF_ACCEPT) + return ret; + } else { + pr_debug("Already setup manip %s for ct %p (status bits 0x%lx)\n", + maniptype == NF_NAT_MANIP_SRC ? "SRC" : "DST", + ct, ct->status); + if (nf_nat_oif_changed(state->hook, ctinfo, nat, + state->out)) + goto oif_changed; + } + break; + default: + /* ESTABLISHED */ + WARN_ON(ctinfo != IP_CT_ESTABLISHED && + ctinfo != IP_CT_ESTABLISHED_REPLY); + if (nf_nat_oif_changed(state->hook, ctinfo, nat, state->out)) + goto oif_changed; + } + + return nf_nat_packet(ct, ctinfo, state->hook, skb); + +oif_changed: + nf_ct_kill_acct(ct, ctinfo, skb); + return NF_DROP; +} +EXPORT_SYMBOL_GPL(nf_nat_inet_fn); + struct nf_nat_proto_clean { u8 l3proto; u8 l4proto; -- cgit v1.2.3-59-g8ed1b