1 files changed, 63 insertions, 1 deletions

diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c
index 93b128827b6d..22fa92b9aeeb 100644
--- a/drivers/net/ovpn/io.c
+++ b/drivers/net/ovpn/io.c
@@ -9,15 +9,77 @@
 
 #include <linux/netdevice.h>
 #include <linux/skbuff.h>
+#include <net/gro_cells.h>
 #include <net/gso.h>
 
-#include "io.h"
 #include "ovpnpriv.h"
 #include "peer.h"
+#include "io.h"
+#include "netlink.h"
+#include "proto.h"
 #include "udp.h"
 #include "skb.h"
 #include "socket.h"
 
+/* Called after decrypt to write the IP packet to the device.
+ * This method is expected to manage/free the skb.
+ */
+static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+	unsigned int pkt_len;
+	int ret;
+
+	/* we can't guarantee the packet wasn't corrupted before entering the
+	 * VPN, therefore we give other layers a chance to check that
+	 */
+	skb->ip_summed = CHECKSUM_NONE;
+
+	/* skb hash for transport packet no longer valid after decapsulation */
+	skb_clear_hash(skb);
+
+	/* post-decrypt scrub -- prepare to inject encapsulated packet onto the
+	 * interface, based on __skb_tunnel_rx() in dst.h
+	 */
+	skb->dev = peer->ovpn->dev;
+	skb_set_queue_mapping(skb, 0);
+	skb_scrub_packet(skb, true);
+
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
+	skb_reset_inner_headers(skb);
+
+	/* cause packet to be "received" by the interface */
+	pkt_len = skb->len;
+	ret = gro_cells_receive(&peer->ovpn->gro_cells, skb);
+	if (likely(ret == NET_RX_SUCCESS))
+		/* update RX stats with the size of decrypted packet */
+		dev_dstats_rx_add(peer->ovpn->dev, pkt_len);
+}
+
+static void ovpn_decrypt_post(struct sk_buff *skb, int ret)
+{
+	struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;
+
+	if (unlikely(ret < 0))
+		goto drop;
+
+	ovpn_netdev_write(peer, skb);
+	/* skb is passed to upper layer - don't free it */
+	skb = NULL;
+drop:
+	if (unlikely(skb))
+		dev_dstats_rx_dropped(peer->ovpn->dev);
+	ovpn_peer_put(peer);
+	kfree_skb(skb);
+}
+
+/* RX path entry point: decrypt packet and forward it to the device */
+void ovpn_recv(struct ovpn_peer *peer, struct sk_buff *skb)
+{
+	ovpn_skb_cb(skb)->peer = peer;
+	ovpn_decrypt_post(skb, 0);
+}
+
 static void ovpn_encrypt_post(struct sk_buff *skb, int ret)
 {
 	struct ovpn_peer *peer = ovpn_skb_cb(skb)->peer;