net: vrf: Implement get_saddr for IPv6
IPv6 source address selection needs to consider the real egress route.
Similar to IPv4 implement a get_saddr6 method which is called if
source address has not been set. The get_saddr6 method does a full
lookup which means pulling a route from the VRF FIB table and properly
considering linklocal/multicast destination addresses. Lookup failures
(eg., unreachable) then cause the source address selection to fail
which gets propagated back to the caller.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index fd32175..1dfc402 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -910,6 +910,13 @@
int err;
int flags = 0;
+ if (ipv6_addr_any(&fl6->saddr) && fl6->flowi6_oif &&
+ (!*dst || !(*dst)->error)) {
+ err = l3mdev_get_saddr6(net, sk, fl6);
+ if (err)
+ goto out_err;
+ }
+
/* The correct way to handle this would be to do
* ip6_route_get_saddr, and then ip6_route_output; however,
* the route-specific preferred source forces the
@@ -999,10 +1006,11 @@
return 0;
out_err_release:
- if (err == -ENETUNREACH)
- IP6_INC_STATS(net, NULL, IPSTATS_MIB_OUTNOROUTES);
dst_release(*dst);
*dst = NULL;
+out_err:
+ if (err == -ENETUNREACH)
+ IP6_INC_STATS(net, NULL, IPSTATS_MIB_OUTNOROUTES);
return err;
}
diff --git a/net/l3mdev/l3mdev.c b/net/l3mdev/l3mdev.c
index d90e4ef..c4a1c3e 100644
--- a/net/l3mdev/l3mdev.c
+++ b/net/l3mdev/l3mdev.c
@@ -162,6 +162,30 @@
}
EXPORT_SYMBOL_GPL(l3mdev_get_saddr);
+int l3mdev_get_saddr6(struct net *net, const struct sock *sk,
+ struct flowi6 *fl6)
+{
+ struct net_device *dev;
+ int rc = 0;
+
+ 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_saddr6)
+ rc = dev->l3mdev_ops->l3mdev_get_saddr6(dev, sk, fl6);
+
+ rcu_read_unlock();
+ }
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(l3mdev_get_saddr6);
+
/**
* l3mdev_fib_rule_match - Determine if flowi references an
* L3 master device
