Merge branch 'l3mdev-send-enslaved'

David Ahern says:

====================
net: l3mdev: Allow send on enslaved interface

First patch preps for the second. The second is required for several use
cases such as ping on an interface and BFD that need to send packets on
a specific interface, including ones enslaved to a VRF device.

v2
- fixed brackets on both patches per comment from DaveM
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 68 insertions, 1 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 8c8c655..a1f2830 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2146,6 +2146,7 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 	unsigned int flags = 0;
 	struct fib_result res;
 	struct rtable *rth;
+	int master_idx;
 	int orig_oif;
 	int err = -ENETUNREACH;
 
@@ -2155,6 +2156,9 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 
 	orig_oif = fl4->flowi4_oif;
 
+	master_idx = l3mdev_master_ifindex_by_index(net, fl4->flowi4_oif);
+	if (master_idx)
+		fl4->flowi4_oif = master_idx;
 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
 	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
 	fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index af46e19..c42fa1d 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1190,7 +1190,7 @@ struct dst_entry *ip6_route_output_flags(struct net *net, const struct sock *sk,
 	struct dst_entry *dst;
 	bool any_src;
 
-	dst = l3mdev_rt6_dst_by_oif(net, fl6);
+	dst = l3mdev_get_rt6_dst(net, fl6);
 	if (dst)
 		return dst;
 
diff --git a/net/l3mdev/l3mdev.c b/net/l3mdev/l3mdev.c
index e925037..6651a78 100644
--- a/net/l3mdev/l3mdev.c
+++ b/net/l3mdev/l3mdev.c
@@ -97,3 +97,66 @@ u32 l3mdev_fib_table_by_index(struct net *net, int ifindex)
 	return tb_id;
 }
 EXPORT_SYMBOL_GPL(l3mdev_fib_table_by_index);
+
+/**
+ *	l3mdev_get_rt6_dst - IPv6 route lookup based on flow. Returns
+ *			     cached route for L3 master device if relevant
+ *			     to flow
+ *	@net: network namespace for device index lookup
+ *	@fl6: IPv6 flow struct for lookup
+ */
+
+struct dst_entry *l3mdev_get_rt6_dst(struct net *net,
+				     const struct flowi6 *fl6)
+{
+	struct dst_entry *dst = NULL;
+	struct net_device *dev;
+
+	if (fl6->flowi6_oif) {
+		rcu_read_lock();
+
+		dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
+		if (dev && netif_is_l3_slave(dev))
+			dev = netdev_master_upper_dev_get_rcu(dev);
+
+		if (dev && netif_is_l3_master(dev) &&
+		    dev->l3mdev_ops->l3mdev_get_rt6_dst)
+			dst = dev->l3mdev_ops->l3mdev_get_rt6_dst(dev, fl6);
+
+		rcu_read_unlock();
+	}
+
+	return dst;
+}
+EXPORT_SYMBOL_GPL(l3mdev_get_rt6_dst);
+
+/**
+ *	l3mdev_get_saddr - get source address for a flow based on an interface
+ *			   enslaved to an L3 master device
+ *	@net: network namespace for device index lookup
+ *	@ifindex: Interface index
+ *	@fl4: IPv4 flow struct
+ */
+
+int l3mdev_get_saddr(struct net *net, int ifindex, struct flowi4 *fl4)
+{
+	struct net_device *dev;
+	int rc = 0;
+
+	if (ifindex) {
+		rcu_read_lock();
+
+		dev = dev_get_by_index_rcu(net, ifindex);
+		if (dev && netif_is_l3_slave(dev))
+			dev = netdev_master_upper_dev_get_rcu(dev);
+
+		if (dev && netif_is_l3_master(dev) &&
+		    dev->l3mdev_ops->l3mdev_get_saddr)
+			rc = dev->l3mdev_ops->l3mdev_get_saddr(dev, fl4);
+
+		rcu_read_unlock();
+	}
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(l3mdev_get_saddr);