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Message-Id: <20180720130906.27687-12-pablo@netfilter.org>
Date: Fri, 20 Jul 2018 15:08:39 +0200
From: Pablo Neira Ayuso <pablo@...filter.org>
To: netfilter-devel@...r.kernel.org
Cc: davem@...emloft.net, netdev@...r.kernel.org
Subject: [PATCH 11/38] netfilter: conntrack: remove get_l4proto indirection from l3 protocol trackers
From: Florian Westphal <fw@...len.de>
Handle it in the core instead.
ipv6_skip_exthdr() is built-in even if ipv6 is a module, i.e. this
doesn't create an ipv6 dependency.
Signed-off-by: Florian Westphal <fw@...len.de>
Signed-off-by: Pablo Neira Ayuso <pablo@...filter.org>
---
include/net/netfilter/nf_conntrack_l3proto.h | 8 --
net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c | 30 -------
net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c | 29 -------
net/netfilter/Makefile | 2 +-
net/netfilter/nf_conntrack_core.c | 108 ++++++++++++++++++++-----
net/netfilter/nf_conntrack_l3proto_generic.c | 46 -----------
net/netfilter/nf_conntrack_proto.c | 5 ++
7 files changed, 94 insertions(+), 134 deletions(-)
delete mode 100644 net/netfilter/nf_conntrack_l3proto_generic.c
diff --git a/include/net/netfilter/nf_conntrack_l3proto.h b/include/net/netfilter/nf_conntrack_l3proto.h
index 164641c743a5..5f160375c93a 100644
--- a/include/net/netfilter/nf_conntrack_l3proto.h
+++ b/include/net/netfilter/nf_conntrack_l3proto.h
@@ -24,14 +24,6 @@ struct nf_conntrack_l3proto {
/* size of tuple nlattr, fills a hole */
u16 nla_size;
- /*
- * Called before tracking.
- * *dataoff: offset of protocol header (TCP, UDP,...) in skb
- * *protonum: protocol number
- */
- int (*get_l4proto)(const struct sk_buff *skb, unsigned int nhoff,
- unsigned int *dataoff, u_int8_t *protonum);
-
/* Called when netns wants to use connection tracking */
int (*net_ns_get)(struct net *);
void (*net_ns_put)(struct net *);
diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
index e10e38c443ab..9fbf6c7f8ece 100644
--- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c
@@ -38,35 +38,6 @@ struct conntrack4_net {
unsigned int users;
};
-static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
- unsigned int *dataoff, u_int8_t *protonum)
-{
- const struct iphdr *iph;
- struct iphdr _iph;
-
- iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
- if (iph == NULL)
- return -NF_ACCEPT;
-
- /* Conntrack defragments packets, we might still see fragments
- * inside ICMP packets though. */
- if (iph->frag_off & htons(IP_OFFSET))
- return -NF_ACCEPT;
-
- *dataoff = nhoff + (iph->ihl << 2);
- *protonum = iph->protocol;
-
- /* Check bogus IP headers */
- if (*dataoff > skb->len) {
- pr_debug("nf_conntrack_ipv4: bogus IPv4 packet: "
- "nhoff %u, ihl %u, skblen %u\n",
- nhoff, iph->ihl << 2, skb->len);
- return -NF_ACCEPT;
- }
-
- return NF_ACCEPT;
-}
-
static unsigned int ipv4_helper(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
@@ -297,7 +268,6 @@ static void ipv4_hooks_unregister(struct net *net)
const struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4 = {
.l3proto = PF_INET,
- .get_l4proto = ipv4_get_l4proto,
.net_ns_get = ipv4_hooks_register,
.net_ns_put = ipv4_hooks_unregister,
.me = THIS_MODULE,
diff --git a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
index f8051fe20489..37ab25645cf2 100644
--- a/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c
@@ -41,34 +41,6 @@ struct conntrack6_net {
unsigned int users;
};
-static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
- unsigned int *dataoff, u_int8_t *protonum)
-{
- unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
- __be16 frag_off;
- int protoff;
- u8 nexthdr;
-
- if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
- &nexthdr, sizeof(nexthdr)) != 0) {
- pr_debug("ip6_conntrack_core: can't get nexthdr\n");
- return -NF_ACCEPT;
- }
- protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
- /*
- * (protoff == skb->len) means the packet has not data, just
- * IPv6 and possibly extensions headers, but it is tracked anyway
- */
- if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
- pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
- return -NF_ACCEPT;
- }
-
- *dataoff = protoff;
- *protonum = nexthdr;
- return NF_ACCEPT;
-}
-
static unsigned int ipv6_helper(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
@@ -281,7 +253,6 @@ static void ipv6_hooks_unregister(struct net *net)
const struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 = {
.l3proto = PF_INET6,
- .get_l4proto = ipv6_get_l4proto,
.net_ns_get = ipv6_hooks_register,
.net_ns_put = ipv6_hooks_unregister,
.me = THIS_MODULE,
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 44449389e527..f132ea850778 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -1,7 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
netfilter-objs := core.o nf_log.o nf_queue.o nf_sockopt.o utils.o
-nf_conntrack-y := nf_conntrack_core.o nf_conntrack_standalone.o nf_conntrack_expect.o nf_conntrack_helper.o nf_conntrack_proto.o nf_conntrack_l3proto_generic.o nf_conntrack_proto_generic.o nf_conntrack_proto_tcp.o nf_conntrack_proto_udp.o nf_conntrack_extend.o nf_conntrack_acct.o nf_conntrack_seqadj.o
+nf_conntrack-y := nf_conntrack_core.o nf_conntrack_standalone.o nf_conntrack_expect.o nf_conntrack_helper.o nf_conntrack_proto.o nf_conntrack_proto_generic.o nf_conntrack_proto_tcp.o nf_conntrack_proto_udp.o nf_conntrack_extend.o nf_conntrack_acct.o nf_conntrack_seqadj.o
nf_conntrack-$(CONFIG_NF_CONNTRACK_TIMEOUT) += nf_conntrack_timeout.o
nf_conntrack-$(CONFIG_NF_CONNTRACK_TIMESTAMP) += nf_conntrack_timestamp.o
nf_conntrack-$(CONFIG_NF_CONNTRACK_EVENTS) += nf_conntrack_ecache.o
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 14c040805b32..0674c6e5bfed 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -37,7 +37,6 @@
#include <linux/rculist_nulls.h>
#include <net/netfilter/nf_conntrack.h>
-#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_expect.h>
#include <net/netfilter/nf_conntrack_helper.h>
@@ -55,6 +54,7 @@
#include <net/netfilter/nf_nat_core.h>
#include <net/netfilter/nf_nat_helper.h>
#include <net/netns/hash.h>
+#include <net/ip.h>
#include "nf_internals.h"
@@ -273,21 +273,94 @@ nf_ct_get_tuple(const struct sk_buff *skb,
return l4proto->pkt_to_tuple(skb, dataoff, net, tuple);
}
+static int ipv4_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
+ u_int8_t *protonum)
+{
+ int dataoff = -1;
+#if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV4)
+ const struct iphdr *iph;
+ struct iphdr _iph;
+
+ iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
+ if (!iph)
+ return -1;
+
+ /* Conntrack defragments packets, we might still see fragments
+ * inside ICMP packets though.
+ */
+ if (iph->frag_off & htons(IP_OFFSET))
+ return -1;
+
+ dataoff = nhoff + (iph->ihl << 2);
+ *protonum = iph->protocol;
+
+ /* Check bogus IP headers */
+ if (dataoff > skb->len) {
+ pr_debug("bogus IPv4 packet: nhoff %u, ihl %u, skblen %u\n",
+ nhoff, iph->ihl << 2, skb->len);
+ return -1;
+ }
+#endif
+ return dataoff;
+}
+
+static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
+ u8 *protonum)
+{
+ int protoff = -1;
+#if IS_ENABLED(CONFIG_NF_CONNTRACK_IPV6)
+ unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
+ __be16 frag_off;
+ u8 nexthdr;
+
+ if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
+ &nexthdr, sizeof(nexthdr)) != 0) {
+ pr_debug("can't get nexthdr\n");
+ return -1;
+ }
+ protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
+ /*
+ * (protoff == skb->len) means the packet has not data, just
+ * IPv6 and possibly extensions headers, but it is tracked anyway
+ */
+ if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
+ pr_debug("can't find proto in pkt\n");
+ return -1;
+ }
+
+ *protonum = nexthdr;
+#endif
+ return protoff;
+}
+
+static int get_l4proto(const struct sk_buff *skb,
+ unsigned int nhoff, u8 pf, u8 *l4num)
+{
+ switch (pf) {
+ case NFPROTO_IPV4:
+ return ipv4_get_l4proto(skb, nhoff, l4num);
+ case NFPROTO_IPV6:
+ return ipv6_get_l4proto(skb, nhoff, l4num);
+ default:
+ *l4num = 0;
+ break;
+ }
+ return -1;
+}
+
bool nf_ct_get_tuplepr(const struct sk_buff *skb, unsigned int nhoff,
u_int16_t l3num,
struct net *net, struct nf_conntrack_tuple *tuple)
{
- const struct nf_conntrack_l3proto *l3proto;
const struct nf_conntrack_l4proto *l4proto;
- unsigned int protoff;
- u_int8_t protonum;
+ u8 protonum;
+ int protoff;
int ret;
rcu_read_lock();
- l3proto = __nf_ct_l3proto_find(l3num);
- ret = l3proto->get_l4proto(skb, nhoff, &protoff, &protonum);
- if (ret != NF_ACCEPT) {
+ protoff = get_l4proto(skb, nhoff, l3num, &protonum);
+ if (protoff <= 0) {
rcu_read_unlock();
return false;
}
@@ -1397,14 +1470,12 @@ unsigned int
nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
struct sk_buff *skb)
{
- const struct nf_conntrack_l3proto *l3proto;
const struct nf_conntrack_l4proto *l4proto;
struct nf_conn *ct, *tmpl;
enum ip_conntrack_info ctinfo;
unsigned int *timeouts;
- unsigned int dataoff;
u_int8_t protonum;
- int ret;
+ int dataoff, ret;
tmpl = nf_ct_get(skb, &ctinfo);
if (tmpl || ctinfo == IP_CT_UNTRACKED) {
@@ -1418,14 +1489,12 @@ nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
}
/* rcu_read_lock()ed by nf_hook_thresh */
- l3proto = __nf_ct_l3proto_find(pf);
- ret = l3proto->get_l4proto(skb, skb_network_offset(skb),
- &dataoff, &protonum);
- if (ret <= 0) {
+ dataoff = get_l4proto(skb, skb_network_offset(skb), pf, &protonum);
+ if (dataoff <= 0) {
pr_debug("not prepared to track yet or error occurred\n");
NF_CT_STAT_INC_ATOMIC(net, error);
NF_CT_STAT_INC_ATOMIC(net, invalid);
- ret = -ret;
+ ret = NF_ACCEPT;
goto out;
}
@@ -1641,14 +1710,14 @@ static void nf_conntrack_attach(struct sk_buff *nskb, const struct sk_buff *skb)
static int nf_conntrack_update(struct net *net, struct sk_buff *skb)
{
- const struct nf_conntrack_l3proto *l3proto;
const struct nf_conntrack_l4proto *l4proto;
struct nf_conntrack_tuple_hash *h;
struct nf_conntrack_tuple tuple;
enum ip_conntrack_info ctinfo;
struct nf_nat_hook *nat_hook;
- unsigned int dataoff, status;
+ unsigned int status;
struct nf_conn *ct;
+ int dataoff;
u16 l3num;
u8 l4num;
@@ -1657,10 +1726,9 @@ static int nf_conntrack_update(struct net *net, struct sk_buff *skb)
return 0;
l3num = nf_ct_l3num(ct);
- l3proto = nf_ct_l3proto_find_get(l3num);
- if (l3proto->get_l4proto(skb, skb_network_offset(skb), &dataoff,
- &l4num) <= 0)
+ dataoff = get_l4proto(skb, skb_network_offset(skb), l3num, &l4num);
+ if (dataoff <= 0)
return -1;
l4proto = nf_ct_l4proto_find_get(l3num, l4num);
diff --git a/net/netfilter/nf_conntrack_l3proto_generic.c b/net/netfilter/nf_conntrack_l3proto_generic.c
deleted file mode 100644
index d6a8fe591ccc..000000000000
--- a/net/netfilter/nf_conntrack_l3proto_generic.c
+++ /dev/null
@@ -1,46 +0,0 @@
-/*
- * (C) 2003,2004 USAGI/WIDE Project <http://www.linux-ipv6.org>
- *
- * Based largely upon the original ip_conntrack code which
- * had the following copyright information:
- *
- * (C) 1999-2001 Paul `Rusty' Russell
- * (C) 2002-2004 Netfilter Core Team <coreteam@...filter.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * Author:
- * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@...hiba.co.jp>
- */
-
-#include <linux/types.h>
-#include <linux/ip.h>
-#include <linux/netfilter.h>
-#include <linux/module.h>
-#include <linux/skbuff.h>
-#include <linux/icmp.h>
-#include <linux/sysctl.h>
-#include <net/ip.h>
-
-#include <linux/netfilter_ipv4.h>
-#include <net/netfilter/nf_conntrack.h>
-#include <net/netfilter/nf_conntrack_l4proto.h>
-#include <net/netfilter/nf_conntrack_l3proto.h>
-#include <net/netfilter/nf_conntrack_core.h>
-#include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
-
-static int generic_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
- unsigned int *dataoff, u_int8_t *protonum)
-{
- /* Never track !!! */
- return -NF_ACCEPT;
-}
-
-
-struct nf_conntrack_l3proto nf_conntrack_l3proto_generic __read_mostly = {
- .l3proto = PF_UNSPEC,
- .get_l4proto = generic_get_l4proto,
-};
-EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_generic);
diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c
index 859cb303bb91..39df72bb9d56 100644
--- a/net/netfilter/nf_conntrack_proto.c
+++ b/net/netfilter/nf_conntrack_proto.c
@@ -35,6 +35,11 @@ EXPORT_SYMBOL_GPL(nf_ct_l3protos);
static DEFINE_MUTEX(nf_ct_proto_mutex);
+struct nf_conntrack_l3proto nf_conntrack_l3proto_generic __read_mostly = {
+ .l3proto = PF_UNSPEC,
+};
+EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_generic);
+
#ifdef CONFIG_SYSCTL
static int
nf_ct_register_sysctl(struct net *net,
--
2.11.0
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