packet: deliver VLAN TCI to userspace

Store the VLAN tag in the auxillary data/tpacket2_hdr so userspace can
properly deal with hardware VLAN tagging/stripping.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h
index d4d3c82448f5..a630295b255f 100644
--- a/include/linux/if_packet.h
+++ b/include/linux/if_packet.h
@@ -59,6 +59,7 @@ struct tpacket_auxdata
         __u32           tp_snaplen;
         __u16           tp_mac;
         __u16           tp_net;
+        __u16           tp_vlan_tci;
 };
 
 struct tpacket_hdr
@@ -90,6 +91,7 @@ struct tpacket2_hdr
         __u16           tp_net;
         __u32           tp_sec;
         __u32           tp_nsec;
+        __u16           tp_vlan_tci;
 };
 
 #define TPACKET2_HDRLEN         (TPACKET_ALIGN(sizeof(struct tpacket2_hdr)) + sizeof(struct sockaddr_ll))
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 4f059775d48f..db792e02a37f 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -702,6 +702,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, struct packe
                         getnstimeofday(&ts);
                 h.h2->tp_sec = ts.tv_sec;
                 h.h2->tp_nsec = ts.tv_nsec;
+                h.h2->tp_vlan_tci = skb->vlan_tci;
                 hdrlen = sizeof(*h.h2);
                 break;
         default:
@@ -1172,6 +1173,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock,
                 aux.tp_snaplen = skb->len;
                 aux.tp_mac = 0;
                 aux.tp_net = skb_network_offset(skb);
+                aux.tp_vlan_tci = skb->vlan_tci;
 
                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
         }