@@ -999,6 +999,46 @@ static struct dst_entry *vrf_get_rt6_dst(const struct net_device *dev,
return dst;
}
+
+/* called under rcu_read_lock */
+static int vrf_get_saddr6(struct net_device *dev, const struct sock *sk,
+ struct flowi6 *fl6)
+{
+ struct net *net = dev_net(dev);
+ struct dst_entry *dst;
+ struct rt6_info *rt;
+ int err;
+
+ if (rt6_need_strict(&fl6->daddr)) {
+ rt = vrf_ip6_route_lookup(net, dev, fl6, fl6->flowi6_oif,
+ RT6_LOOKUP_F_IFACE);
+ if (unlikely(!rt))
+ return 0;
+
+ dst = &rt->dst;
+ } else {
+ __u8 flags = fl6->flowi6_flags;
+
+ fl6->flowi6_flags |= FLOWI_FLAG_L3MDEV_SRC;
+ fl6->flowi6_flags |= FLOWI_FLAG_SKIP_NH_OIF;
+
+ dst = ip6_route_output(net, sk, fl6);
+ rt = (struct rt6_info *)dst;
+
+ fl6->flowi6_flags = flags;
+ }
+
+ err = dst->error;
+ if (!err) {
+ err = ip6_route_get_saddr(net, rt, &fl6->daddr,
+ sk ? inet6_sk(sk)->srcprefs : 0,
+ &fl6->saddr);
+ }
+
+ dst_release(dst);
+
+ return err;
+}
#endif
static const struct l3mdev_ops vrf_l3mdev_ops = {
@@ -1008,6 +1048,7 @@ static const struct l3mdev_ops vrf_l3mdev_ops = {
.l3mdev_l3_rcv = vrf_l3_rcv,
#if IS_ENABLED(CONFIG_IPV6)
.l3mdev_get_rt6_dst = vrf_get_rt6_dst,
+ .l3mdev_get_saddr6 = vrf_get_saddr6,
#endif
};
@@ -39,6 +39,9 @@ struct l3mdev_ops {
/* IPv6 ops */
struct dst_entry * (*l3mdev_get_rt6_dst)(const struct net_device *dev,
struct flowi6 *fl6);
+ int (*l3mdev_get_saddr6)(struct net_device *dev,
+ const struct sock *sk,
+ struct flowi6 *fl6);
};
#ifdef CONFIG_NET_L3_MASTER_DEV
@@ -140,6 +143,8 @@ static inline bool netif_index_is_l3_master(struct net *net, int ifindex)
int l3mdev_get_saddr(struct net *net, int ifindex, struct flowi4 *fl4);
struct dst_entry *l3mdev_get_rt6_dst(struct net *net, struct flowi6 *fl6);
+int l3mdev_get_saddr6(struct net *net, const struct sock *sk,
+ struct flowi6 *fl6);
static inline
struct sk_buff *l3mdev_l3_rcv(struct sk_buff *skb, u16 proto)
@@ -230,6 +235,12 @@ struct dst_entry *l3mdev_get_rt6_dst(struct net *net, struct flowi6 *fl6)
return NULL;
}
+static inline int l3mdev_get_saddr6(struct net *net, const struct sock *sk,
+ struct flowi6 *fl6)
+{
+ return 0;
+}
+
static inline
struct sk_buff *l3mdev_ip_rcv(struct sk_buff *skb)
{
@@ -910,6 +910,13 @@ static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
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 @@ static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
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;
}
@@ -162,6 +162,30 @@ int l3mdev_get_saddr(struct net *net, int ifindex, struct flowi4 *fl4)
}
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
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> --- drivers/net/vrf.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/net/l3mdev.h | 11 +++++++++++ net/ipv6/ip6_output.c | 12 ++++++++++-- net/l3mdev/l3mdev.c | 24 ++++++++++++++++++++++++ 4 files changed, 86 insertions(+), 2 deletions(-)