[AF_PACKET]: Add option to return orig_dev to userspace.
Add a packet socket option to allow the orig_dev index to be returned
to userspace when passing traffic through a decapsulated device, such
as the bonding driver.
This is very useful for layer 2 traffic being able to report which
physical device actually received the traffic, instead of having the
encapsulating device hide that information.
The new option is called PACKET_ORIGDEV.
Signed-off-by: Peter P. Waskiewicz Jr. <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 36388b2..02e401c 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -201,7 +201,8 @@
struct packet_type prot_hook;
spinlock_t bind_lock;
unsigned int running:1, /* prot_hook is attached*/
- auxdata:1;
+ auxdata:1,
+ origdev:1;
int ifindex; /* bound device */
__be16 num;
#ifdef CONFIG_PACKET_MULTICAST
@@ -528,7 +529,10 @@
sll->sll_hatype = dev->type;
sll->sll_protocol = skb->protocol;
sll->sll_pkttype = skb->pkt_type;
- sll->sll_ifindex = dev->ifindex;
+ if (unlikely(po->origdev) && skb->pkt_type == PACKET_HOST)
+ sll->sll_ifindex = orig_dev->ifindex;
+ else
+ sll->sll_ifindex = dev->ifindex;
sll->sll_halen = 0;
if (dev->hard_header_parse)
@@ -673,7 +677,10 @@
sll->sll_hatype = dev->type;
sll->sll_protocol = skb->protocol;
sll->sll_pkttype = skb->pkt_type;
- sll->sll_ifindex = dev->ifindex;
+ if (unlikely(po->origdev) && skb->pkt_type == PACKET_HOST)
+ sll->sll_ifindex = orig_dev->ifindex;
+ else
+ sll->sll_ifindex = dev->ifindex;
h->tp_status = status;
smp_mb();
@@ -1413,6 +1420,18 @@
po->auxdata = !!val;
return 0;
}
+ case PACKET_ORIGDEV:
+ {
+ int val;
+
+ if (optlen < sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->origdev = !!val;
+ return 0;
+ }
default:
return -ENOPROTOOPT;
}
@@ -1456,6 +1475,13 @@
data = &val;
break;
+ case PACKET_ORIGDEV:
+ if (len > sizeof(int))
+ len = sizeof(int);
+ val = po->origdev;
+
+ data = &val;
+ break;
default:
return -ENOPROTOOPT;
}