This patchset sequentially adds namespace parameter to fib_lookup and
inetdev_by_index. After that it is possible to pass network namespace
from input packet to routing engine.

Output path is much more intrusive and will be sent separately.

Signed-off-by: Denis V. Lunev <den@openvz.org>

Correct network namespace is available inside fib_validate_source. It can be
obtained from the device passed in. The device is not NULL as in_device is
obtained from it just above.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 net/ipv4/fib_frontend.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index dcd3a28..39b8b35 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -243,6 +243,7 @@ int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 	struct fib_result res;
 	int no_addr, rpf;
 	int ret;
+	struct net *net;
 
 	no_addr = rpf = 0;
 	rcu_read_lock();
@@ -256,7 +257,8 @@ int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 	if (in_dev == NULL)
 		goto e_inval;
 
-	if (fib_lookup(&init_net, &fl, &res))
+	net = dev->nd_net;
+	if (fib_lookup(net, &fl, &res))
 		goto last_resort;
 	if (res.type != RTN_UNICAST)
 		goto e_inval_res;
@@ -280,7 +282,7 @@ int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 	fl.oif = dev->ifindex;
 
 	ret = 0;
-	if (fib_lookup(&init_net, &fl, &res) == 0) {
+	if (fib_lookup(net, &fl, &res) == 0) {
 		if (res.type == RTN_UNICAST) {
 			*spec_dst = FIB_RES_PREFSRC(res);
 			ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
-- 
1.5.3.rc5

The packet on the input path always has a referrence to an input network
device it is passed from. Extract network namespace from it.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 net/ipv4/route.c |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index c107bc3..b3c6122 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1881,6 +1881,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	__be32		spec_dst;
 	int		err = -EINVAL;
 	int		free_res = 0;
+	struct net    * net = dev->nd_net;
 
 	/* IP on this device is disabled. */
 
@@ -1911,7 +1912,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	/*
 	 *	Now we are ready to route packet.
 	 */
-	if ((err = fib_lookup(&init_net, &fl, &res)) != 0) {
+	if ((err = fib_lookup(net, &fl, &res)) != 0) {
 		if (!IN_DEV_FORWARD(in_dev))
 			goto e_hostunreach;
 		goto no_route;
@@ -1926,7 +1927,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	if (res.type == RTN_LOCAL) {
 		int result;
 		result = fib_validate_source(saddr, daddr, tos,
-					     init_net.loopback_dev->ifindex,
+					     net->loopback_dev->ifindex,
 					     dev, &spec_dst, &itag);
 		if (result < 0)
 			goto martian_source;
@@ -1988,7 +1989,7 @@ local_input:
 #endif
 	rth->rt_iif	=
 	rth->fl.iif	= dev->ifindex;
-	rth->u.dst.dev	= init_net.loopback_dev;
+	rth->u.dst.dev	= net->loopback_dev;
 	dev_hold(rth->u.dst.dev);
 	rth->idev	= in_dev_get(rth->u.dst.dev);
 	rth->rt_gateway	= daddr;
-- 
1.5.3.rc5

Correct network namespace is already used in fib_check_nh. Re-work its usage
for better readability and pass into fib_lookup & inetdev_by_index.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 net/ipv4/fib_semantics.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 8b47e11..c791286 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -519,7 +519,9 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
 			struct fib_nh *nh)
 {
 	int err;
+	struct net *net;
 
+	net = cfg->fc_nlinfo.nl_net;
 	if (nh->nh_gw) {
 		struct fib_result res;
 
@@ -532,11 +534,9 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
 
 			if (cfg->fc_scope >= RT_SCOPE_LINK)
 				return -EINVAL;
-			if (inet_addr_type(cfg->fc_nlinfo.nl_net,
-					   nh->nh_gw) != RTN_UNICAST)
+			if (inet_addr_type(net, nh->nh_gw) != RTN_UNICAST)
 				return -EINVAL;
-			if ((dev = __dev_get_by_index(cfg->fc_nlinfo.nl_net,
-						      nh->nh_oif)) == NULL)
+			if ((dev = __dev_get_by_index(net, nh->nh_oif)) == NULL)
 				return -ENODEV;
 			if (!(dev->flags&IFF_UP))
 				return -ENETDOWN;
@@ -559,7 +559,7 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
 			/* It is not necessary, but requires a bit of thinking */
 			if (fl.fl4_scope < RT_SCOPE_LINK)
 				fl.fl4_scope = RT_SCOPE_LINK;
-			if ((err = fib_lookup(&init_net, &fl, &res)) != 0)
+			if ((err = fib_lookup(net, &fl, &res)) != 0)
 				return err;
 		}
 		err = -EINVAL;
@@ -583,7 +583,7 @@ out:
 		if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
 			return -EINVAL;
 
-		in_dev = inetdev_by_index(&init_net, nh->nh_oif);
+		in_dev = inetdev_by_index(net, nh->nh_oif);
 		if (in_dev == NULL)
 			return -ENODEV;
 		if (!(in_dev->dev->flags&IFF_UP)) {
-- 
1.5.3.rc5

ip_rt_get_source is the infamous place for which dst_ifdown kludges have
been implemented. This means that rt->u.dst.dev can be safely dereferrenced
obtain nd_net.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 net/ipv4/route.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index b3c6122..ede0571 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1559,7 +1559,7 @@ void ip_rt_get_source(u8 *addr, struct rtable *rt)
 
 	if (rt->fl.iif == 0)
 		src = rt->rt_src;
-	else if (fib_lookup(&init_net, &rt->fl, &res) == 0) {
+	else if (fib_lookup(rt->u.dst.dev->nd_net, &rt->fl, &res) == 0) {
 		src = FIB_RES_PREFSRC(res);
 		fib_res_put(&res);
 	} else
-- 
1.5.3.rc5

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 include/net/ip_fib.h     |    9 +++++----
 net/ipv4/fib_frontend.c  |    4 ++--
 net/ipv4/fib_rules.c     |    4 ++--
 net/ipv4/fib_semantics.c |    2 +-
 net/ipv4/route.c         |    6 +++---
 5 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 08ebb1e..9daa60b 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -178,15 +178,16 @@ static inline struct fib_table *fib_new_table(struct net *net, u32 id)
 	return fib_get_table(net, id);
 }
 
-static inline int fib_lookup(const struct flowi *flp, struct fib_result *res)
+static inline int fib_lookup(struct net *net, const struct flowi *flp,
+			     struct fib_result *res)
 {
 	struct fib_table *table;
 
-	table = fib_get_table(&init_net, RT_TABLE_LOCAL);
+	table = fib_get_table(net, RT_TABLE_LOCAL);
 	if (!table->tb_lookup(table, flp, res))
 		return 0;
 
-	table = fib_get_table(&init_net, RT_TABLE_MAIN);
+	table = fib_get_table(net, RT_TABLE_MAIN);
 	if (!table->tb_lookup(table, flp, res))
 		return 0;
 	return -ENETUNREACH;
@@ -200,7 +201,7 @@ extern void __net_exit fib4_rules_exit(struct net *net);
 extern u32 fib_rules_tclass(struct fib_result *res);
 #endif
 
-extern int fib_lookup(struct flowi *flp, struct fib_result *res);
+extern int fib_lookup(struct net *n, struct flowi *flp, struct fib_result *res);
 
 extern struct fib_table *fib_new_table(struct net *net, u32 id);
 extern struct fib_table *fib_get_table(struct net *net, u32 id);
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 8c0081c..dcd3a28 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -256,7 +256,7 @@ int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 	if (in_dev == NULL)
 		goto e_inval;
 
-	if (fib_lookup(&fl, &res))
+	if (fib_lookup(&init_net, &fl, &res))
 		goto last_resort;
 	if (res.type != RTN_UNICAST)
 		goto e_inval_res;
@@ -280,7 +280,7 @@ int fib_validate_source(__be32 src, __be32 dst, u8 tos, int oif,
 	fl.oif = dev->ifindex;
 
 	ret = 0;
-	if (fib_lookup(&fl, &res) == 0) {
+	if (fib_lookup(&init_net, &fl, &res) == 0) {
 		if (res.type == RTN_UNICAST) {
 			*spec_dst = FIB_RES_PREFSRC(res);
 			ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index 2b43002..19274d0 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -54,14 +54,14 @@ u32 fib_rules_tclass(struct fib_result *res)
 }
 #endif
 
-int fib_lookup(struct flowi *flp, struct fib_result *res)
+int fib_lookup(struct net *net, struct flowi *flp, struct fib_result *res)
 {
 	struct fib_lookup_arg arg = {
 		.result = res,
 	};
 	int err;
 
-	err = fib_rules_lookup(init_net.ipv4.rules_ops, flp, 0, &arg);
+	err = fib_rules_lookup(net->ipv4.rules_ops, flp, 0, &arg);
 	res->r = arg.rule;
 
 	return err;
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 0e08df4..ecd91c6 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -559,7 +559,7 @@ static int fib_check_nh(struct fib_config *cfg, struct fib_info *fi,
 			/* It is not necessary, but requires a bit of thinking */
 			if (fl.fl4_scope < RT_SCOPE_LINK)
 				fl.fl4_scope = RT_SCOPE_LINK;
-			if ((err = fib_lookup(&fl, &res)) != 0)
+			if ((err = fib_lookup(&init_net, &fl, &res)) != 0)
 				return err;
 		}
 		err = -EINVAL;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 162e738..c107bc3 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1559,7 +1559,7 @@ void ip_rt_get_source(u8 *addr, struct rtable *rt)
 
 	if (rt->fl.iif == 0)
 		src = rt->rt_src;
-	else if (fib_lookup(&rt->fl, &res) == 0) {
+	else if (fib_lookup(&init_net, &rt->fl, &res) == 0) {
 		src = FIB_RES_PREFSRC(res);
 		fib_res_put(&res);
 	} else
@@ -1911,7 +1911,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	/*
 	 *	Now we are ready to route packet.
 	 */
-	if ((err = fib_lookup(&fl, &res)) != 0) {
+	if ((err = fib_lookup(&init_net, &fl, &res)) != 0) {
 		if (!IN_DEV_FORWARD(in_dev))
 			goto e_hostunreach;
 		goto no_route;
@@ -2363,7 +2363,7 @@ static int ip_route_output_slow(struct rtable **rp, const struct flowi *oldflp)
 		goto make_route;
 	}
 
-	if (fib_lookup(&fl, &res)) {
+	if (fib_lookup(&init_net, &fl, &res)) {
 		res.fi = NULL;
 		if (oldflp->oif) {
 			/* Apparently, routing tables are wrong. Assume,
-- 
1.5.3.rc5

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 include/linux/inetdevice.h |    2 +-
 net/ipv4/devinet.c         |    6 +++---
 net/ipv4/fib_semantics.c   |    2 +-
 net/ipv4/igmp.c            |    4 ++--
 net/ipv4/ip_gre.c          |    3 ++-
 5 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index 45f3731..e74a2ee 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -133,7 +133,7 @@ extern struct net_device 	*ip_dev_find(__be32 addr);
 extern int		inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b);
 extern int		devinet_ioctl(unsigned int cmd, void __user *);
 extern void		devinet_init(void);
-extern struct in_device	*inetdev_by_index(int);
+extern struct in_device	*inetdev_by_index(struct net *, int);
 extern __be32		inet_select_addr(const struct net_device *dev, __be32 dst, int scope);
 extern __be32		inet_confirm_addr(struct in_device *in_dev, __be32 dst, __be32 local, int scope);
 extern struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix, __be32 mask);
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index e381edb..21f71bf 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -409,12 +409,12 @@ static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
 	return inet_insert_ifa(ifa);
 }
 
-struct in_device *inetdev_by_index(int ifindex)
+struct in_device *inetdev_by_index(struct net *net, int ifindex)
 {
 	struct net_device *dev;
 	struct in_device *in_dev = NULL;
 	read_lock(&dev_base_lock);
-	dev = __dev_get_by_index(&init_net, ifindex);
+	dev = __dev_get_by_index(net, ifindex);
 	if (dev)
 		in_dev = in_dev_get(dev);
 	read_unlock(&dev_base_lock);
@@ -454,7 +454,7 @@ static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg
 		goto errout;
 
 	ifm = nlmsg_data(nlh);
-	in_dev = inetdev_by_index(ifm->ifa_index);
+	in_dev = inetdev_by_index(net, ifm->ifa_index);
 	if (in_dev == NULL) {
 		err = -ENODEV;
 		goto errout;
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index ecd91c6..8b47e11 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -583,7 +583,7 @@ out:
 		if (nh->nh_flags&(RTNH_F_PERVASIVE|RTNH_F_ONLINK))
 			return -EINVAL;
 
-		in_dev = inetdev_by_index(nh->nh_oif);
+		in_dev = inetdev_by_index(&init_net, nh->nh_oif);
 		if (in_dev == NULL)
 			return -ENODEV;
 		if (!(in_dev->dev->flags&IFF_UP)) {
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 285d262..b4df39a 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1389,7 +1389,7 @@ static struct in_device * ip_mc_find_dev(struct ip_mreqn *imr)
 	struct in_device *idev = NULL;
 
 	if (imr->imr_ifindex) {
-		idev = inetdev_by_index(imr->imr_ifindex);
+		idev = inetdev_by_index(&init_net, imr->imr_ifindex);
 		if (idev)
 			__in_dev_put(idev);
 		return idev;
@@ -2222,7 +2222,7 @@ void ip_mc_drop_socket(struct sock *sk)
 		struct in_device *in_dev;
 		inet->mc_list = iml->next;
 
-		in_dev = inetdev_by_index(iml->multi.imr_ifindex);
+		in_dev = inetdev_by_index(&init_net, iml->multi.imr_ifindex);
 		(void) ip_mc_leave_src(sk, iml, in_dev);
 		if (in_dev != NULL) {
 			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 8b81deb..a74983d 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -1193,7 +1193,8 @@ static int ipgre_close(struct net_device *dev)
 {
 	struct ip_tunnel *t = netdev_priv(dev);
 	if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) {
-		struct in_device *in_dev = inetdev_by_index(t->mlink);
+		struct in_device *in_dev;
+		in_dev = inetdev_by_index(dev->nd_net, t->mlink);
 		if (in_dev) {
 			ip_mc_dec_group(in_dev, t->parms.iph.daddr);
 			in_dev_put(in_dev);
-- 
1.5.3.rc5

From: "Denis V. Lunev" <den@sw.ru>
Date: Mon, 21 Jan 2008 17:49:50 +0300

> This patchset sequentially adds namespace parameter to fib_lookup and
> inetdev_by_index. After that it is possible to pass network namespace
> from input packet to routing engine.
> 
> Output path is much more intrusive and will be sent separately.
> 
> Signed-off-by: Denis V. Lunev <den@openvz.org>

All 6 patches applied, thanks.