From 666953df353194bef76086fa3f126241cbac3e3a Mon Sep 17 00:00:00 2001
From: Alexey Dobriyan <adobriyan@sw.ru>
Date: Mon, 14 Apr 2008 09:56:02 +0200
Subject: [PATCH] [NETFILTER]: ip_tables: per-netns FILTER/MANGLE/RAW tables
for real
Commit 9335f047fe61587ec82ff12fbb1220bcfdd32006 aka
"[NETFILTER]: ip_tables: per-netns FILTER, MANGLE, RAW"
added per-netns _view_ of iptables rules. They were shown to user, but
ignored by filtering code. Now that it's possible to at least ping loopback,
per-netns tables can affect filtering decisions.
netns is taken in case of
PRE_ROUTING, LOCAL_IN -- from in device,
POST_ROUTING, LOCAL_OUT -- from out device,
FORWARD -- from in device which should be equal to out device's netns.
This code is relatively new, so BUG_ON was plugged.
Wrappers were added to a) keep code the same from CONFIG_NET_NS=n users
(overwhelming majority), b) consolidate code in one place -- similar
changes will be done in ipv6 and arp netfilter code.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
---
include/linux/netfilter.h | 54 ++++++++++++++++++++++++++++-
net/ipv4/netfilter/iptable_filter.c | 19 ++++++++--
net/ipv4/netfilter/iptable_mangle.c | 49 ++++++++++++++++++++++----
net/ipv4/netfilter/iptable_raw.c | 6 ++--
4 files changed, 115 insertions(+), 13 deletions(-)
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index 89e6c72ad295..66bc52060fd6 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -6,11 +6,13 @@
#include <linux/types.h>
#include <linux/skbuff.h>
#include <linux/net.h>
+#include <linux/netdevice.h>
#include <linux/if.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/wait.h>
#include <linux/list.h>
+#include <net/net_namespace.h>
#endif
#include <linux/compiler.h>
@@ -76,7 +78,6 @@ extern void netfilter_init(void);
#define NF_MAX_HOOKS 8
struct sk_buff;
-struct net_device;
typedef unsigned int nf_hookfn(unsigned int hooknum,
struct sk_buff *skb,
@@ -320,5 +321,56 @@ extern void (*nf_ct_destroy)(struct nf_conntrack *);
static inline void nf_ct_attach(struct sk_buff *new, struct sk_buff *skb) {}
#endif
+static inline struct net *nf_pre_routing_net(const struct net_device *in,
+ const struct net_device *out)
+{
+#ifdef CONFIG_NET_NS
+ return in->nd_net;
+#else
+ return &init_net;
+#endif
+}
+
+static inline struct net *nf_local_in_net(const struct net_device *in,
+ const struct net_device *out)
+{
+#ifdef CONFIG_NET_NS
+ return in->nd_net;
+#else
+ return &init_net;
+#endif
+}
+
+static inline struct net *nf_forward_net(const struct net_device *in,
+ const struct net_device *out)
+{
+#ifdef CONFIG_NET_NS
+ BUG_ON(in->nd_net != out->nd_net);
+ return in->nd_net;
+#else
+ return &init_net;
+#endif
+}
+
+static inline struct net *nf_local_out_net(const struct net_device *in,
+ const struct net_device *out)
+{
+#ifdef CONFIG_NET_NS
+ return out->nd_net;
+#else
+ return &init_net;
+#endif
+}
+
+static inline struct net *nf_post_routing_net(const struct net_device *in,
+ const struct net_device *out)
+{
+#ifdef CONFIG_NET_NS
+ return out->nd_net;
+#else
+ return &init_net;
+#endif
+}
+
#endif /*__KERNEL__*/
#endif /*__LINUX_NETFILTER_H*/
diff --git a/net/ipv4/netfilter/iptable_filter.c b/net/ipv4/netfilter/iptable_filter.c
index 69f3d7e6e96f..7fcf60adbbed 100644
--- a/net/ipv4/netfilter/iptable_filter.c
+++ b/net/ipv4/netfilter/iptable_filter.c
@@ -62,6 +62,17 @@ static struct xt_table packet_filter = {
};
/* The work comes in here from netfilter.c. */
+static unsigned int
+ipt_local_in_hook(unsigned int hook,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ return ipt_do_table(skb, hook, in, out,
+ nf_local_in_net(in, out)->ipv4.iptable_filter);
+}
+
static unsigned int
ipt_hook(unsigned int hook,
struct sk_buff *skb,
@@ -69,7 +80,8 @@ ipt_hook(unsigned int hook,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
- return ipt_do_table(skb, hook, in, out, init_net.ipv4.iptable_filter);
+ return ipt_do_table(skb, hook, in, out,
+ nf_forward_net(in, out)->ipv4.iptable_filter);
}
static unsigned int
@@ -88,12 +100,13 @@ ipt_local_out_hook(unsigned int hook,
return NF_ACCEPT;
}
- return ipt_do_table(skb, hook, in, out, init_net.ipv4.iptable_filter);
+ return ipt_do_table(skb, hook, in, out,
+ nf_local_out_net(in, out)->ipv4.iptable_filter);
}
static struct nf_hook_ops ipt_ops[] __read_mostly = {
{
- .hook = ipt_hook,
+ .hook = ipt_local_in_hook,
.owner = THIS_MODULE,
.pf = PF_INET,
.hooknum = NF_INET_LOCAL_IN,
diff --git a/net/ipv4/netfilter/iptable_mangle.c b/net/ipv4/netfilter/iptable_mangle.c
index c55a210853a7..ba827035b691 100644
--- a/net/ipv4/netfilter/iptable_mangle.c
+++ b/net/ipv4/netfilter/iptable_mangle.c
@@ -74,13 +74,47 @@ static struct xt_table packet_mangler = {
/* The work comes in here from netfilter.c. */
static unsigned int
-ipt_route_hook(unsigned int hook,
+ipt_pre_routing_hook(unsigned int hook,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ return ipt_do_table(skb, hook, in, out,
+ nf_pre_routing_net(in, out)->ipv4.iptable_mangle);
+}
+
+static unsigned int
+ipt_post_routing_hook(unsigned int hook,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ return ipt_do_table(skb, hook, in, out,
+ nf_post_routing_net(in, out)->ipv4.iptable_mangle);
+}
+
+static unsigned int
+ipt_local_in_hook(unsigned int hook,
+ struct sk_buff *skb,
+ const struct net_device *in,
+ const struct net_device *out,
+ int (*okfn)(struct sk_buff *))
+{
+ return ipt_do_table(skb, hook, in, out,
+ nf_local_in_net(in, out)->ipv4.iptable_mangle);
+}
+
+static unsigned int
+ipt_forward_hook(unsigned int hook,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
- return ipt_do_table(skb, hook, in, out, init_net.ipv4.iptable_mangle);
+ return ipt_do_table(skb, hook, in, out,
+ nf_forward_net(in, out)->ipv4.iptable_mangle);
}
static unsigned int
@@ -112,7 +146,8 @@ ipt_local_hook(unsigned int hook,
daddr = iph->daddr;
tos = iph->tos;
- ret = ipt_do_table(skb, hook, in, out, init_net.ipv4.iptable_mangle);
+ ret = ipt_do_table(skb, hook, in, out,
+ nf_local_out_net(in, out)->ipv4.iptable_mangle);
/* Reroute for ANY change. */
if (ret != NF_DROP && ret != NF_STOLEN && ret != NF_QUEUE) {
iph = ip_hdr(skb);
@@ -130,21 +165,21 @@ ipt_local_hook(unsigned int hook,
static struct nf_hook_ops ipt_ops[] __read_mostly = {
{
- .hook = ipt_route_hook,
+ .hook = ipt_pre_routing_hook,
.owner = THIS_MODULE,
.pf = PF_INET,
.hooknum = NF_INET_PRE_ROUTING,
.priority = NF_IP_PRI_MANGLE,
},
{
- .hook = ipt_route_hook,
+ .hook = ipt_local_in_hook,
.owner = THIS_MODULE,
.pf = PF_INET,
.hooknum = NF_INET_LOCAL_IN,
.priority = NF_IP_PRI_MANGLE,
},
{
- .hook = ipt_route_hook,
+ .hook = ipt_forward_hook,
.owner = THIS_MODULE,
.pf = PF_INET,
.hooknum = NF_INET_FORWARD,
@@ -158,7 +193,7 @@ static struct nf_hook_ops ipt_ops[] __read_mostly = {
.priority = NF_IP_PRI_MANGLE,
},
{
- .hook = ipt_route_hook,
+ .hook = ipt_post_routing_hook,
.owner = THIS_MODULE,
.pf = PF_INET,
.hooknum = NF_INET_POST_ROUTING,
diff --git a/net/ipv4/netfilter/iptable_raw.c b/net/ipv4/netfilter/iptable_raw.c
index e41fe8ca4e1c..4b689742d58b 100644
--- a/net/ipv4/netfilter/iptable_raw.c
+++ b/net/ipv4/netfilter/iptable_raw.c
@@ -52,7 +52,8 @@ ipt_hook(unsigned int hook,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
- return ipt_do_table(skb, hook, in, out, init_net.ipv4.iptable_raw);
+ return ipt_do_table(skb, hook, in, out,
+ nf_pre_routing_net(in, out)->ipv4.iptable_raw);
}
static unsigned int
@@ -70,7 +71,8 @@ ipt_local_hook(unsigned int hook,
"packet.\n");
return NF_ACCEPT;
}
- return ipt_do_table(skb, hook, in, out, init_net.ipv4.iptable_raw);
+ return ipt_do_table(skb, hook, in, out,
+ nf_local_out_net(in, out)->ipv4.iptable_raw);
}
/* 'raw' is the very first table. */