[PATCH V2 net-next 07/14] net/tls: Support TLS device offload with IPv6

[Saeed Mahameed]

From: Ilya Lesokhin <il...@mellanox.com>

Previously get_netdev_for_sock worked only with IPv4.

Signed-off-by: Ilya Lesokhin <il...@mellanox.com>
Signed-off-by: Boris Pismenny <bor...@mellanox.com>
Signed-off-by: Saeed Mahameed <sae...@mellanox.com>
---
 net/tls/tls_device.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 48 insertions(+), 1 deletion(-)

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index e623280ea019..c35fc107d9c5 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -34,6 +34,11 @@
 #include <net/inet_common.h>
 #include <linux/highmem.h>
 #include <linux/netdevice.h>
+#include <net/addrconf.h>
+#include <net/flow.h>
+#include <linux/ipv6.h>
+#include <net/dst.h>
+#include <linux/security.h>
 
 #include <net/tls.h>
 #include <crypto/aead.h>
@@ -99,13 +104,55 @@ static void tls_device_queue_ctx_destruction(struct 
tls_context *ctx)
        spin_unlock_irqrestore(&tls_device_lock, flags);
 }
 
+static inline struct net_device *ipv6_get_netdev(struct sock *sk)
+{
+       struct net_device *dev = NULL;
+#if IS_ENABLED(CONFIG_IPV6)
+       struct inet_sock *inet = inet_sk(sk);
+       struct ipv6_pinfo *np = inet6_sk(sk);
+       struct flowi6 _fl6, *fl6 = &_fl6;
+       struct dst_entry *dst;
+
+       memset(fl6, 0, sizeof(*fl6));
+       fl6->flowi6_proto = sk->sk_protocol;
+       fl6->daddr = sk->sk_v6_daddr;
+       fl6->saddr = np->saddr;
+       fl6->flowlabel = np->flow_label;
+       IP6_ECN_flow_xmit(sk, fl6->flowlabel);
+       fl6->flowi6_oif = sk->sk_bound_dev_if;
+       fl6->flowi6_mark = sk->sk_mark;
+       fl6->fl6_sport = inet->inet_sport;
+       fl6->fl6_dport = inet->inet_dport;
+       fl6->flowi6_uid = sk->sk_uid;
+       security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
+
+       if (ipv6_stub->ipv6_dst_lookup(sock_net(sk), sk, &dst, fl6) < 0)
+               return NULL;
+
+       dev = dst->dev;
+       dev_hold(dev);
+       dst_release(dst);
+
+#endif
+       return dev;
+}
+
 /* We assume that the socket is already connected */
 static struct net_device *get_netdev_for_sock(struct sock *sk)
 {
        struct inet_sock *inet = inet_sk(sk);
        struct net_device *netdev = NULL;
 
-       netdev = dev_get_by_index(sock_net(sk), inet->cork.fl.flowi_oif);
+       if (sk->sk_family == AF_INET)
+               netdev = dev_get_by_index(sock_net(sk),
+                                         inet->cork.fl.flowi_oif);
+       else if (sk->sk_family == AF_INET6) {
+               netdev = ipv6_get_netdev(sk);
+               if (!netdev && !sk->sk_ipv6only &&
+                   ipv6_addr_type(&sk->sk_v6_daddr) == IPV6_ADDR_MAPPED)
+                       netdev = dev_get_by_index(sock_net(sk),
+                                                 inet->cork.fl.flowi_oif);
+       }
 
        return netdev;
 }
-- 
2.14.3