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| author | Ben Greear <greearb@candelatech.com> | 2011-06-01 06:49:10 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-06-01 21:18:03 -0700 |
| commit | a3bcc23e890a6d49d6763d9eb073d711de2e0469 (patch) | |
| tree | c4156e932f081dc14a514d5ab23cd43e590029cd | |
| parent | 41be5a4a3668810bf3687a76c2b017bd437039e0 (diff) | |
| download | linux-a3bcc23e890a6d49d6763d9eb073d711de2e0469.tar.gz linux-a3bcc23e890a6d49d6763d9eb073d711de2e0469.tar.bz2 linux-a3bcc23e890a6d49d6763d9eb073d711de2e0469.zip | |
af-packet: Add flag to distinguish VID 0 from no-vlan.
Currently, user-space cannot determine if a 0 tcp_vlan_tci
means there is no VLAN tag or the VLAN ID was zero.
Add flag to make this explicit. User-space can check for
TP_STATUS_VLAN_VALID || tp_vlan_tci > 0, which will be backwards
compatible. Older could would have just checked for tp_vlan_tci,
so it will work no worse than before.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/if_packet.h | 1 | ||||
| -rw-r--r-- | net/packet/af_packet.c | 15 |
2 files changed, 13 insertions, 3 deletions
diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h index 72bfa5a034dd..6d66ce1791a9 100644 --- a/include/linux/if_packet.h +++ b/include/linux/if_packet.h @@ -70,6 +70,7 @@ struct tpacket_auxdata { #define TP_STATUS_COPY 0x2 #define TP_STATUS_LOSING 0x4 #define TP_STATUS_CSUMNOTREADY 0x8 +#define TP_STATUS_VLAN_VALID 0x10 /* auxdata has valid tp_vlan_tci */ /* Tx ring - header status */ #define TP_STATUS_AVAILABLE 0x0 diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 925f715686a5..ba248d93399a 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -798,7 +798,12 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, getnstimeofday(&ts); h.h2->tp_sec = ts.tv_sec; h.h2->tp_nsec = ts.tv_nsec; - h.h2->tp_vlan_tci = vlan_tx_tag_get(skb); + if (vlan_tx_tag_present(skb)) { + h.h2->tp_vlan_tci = vlan_tx_tag_get(skb); + status |= TP_STATUS_VLAN_VALID; + } else { + h.h2->tp_vlan_tci = 0; + } hdrlen = sizeof(*h.h2); break; default: @@ -1725,8 +1730,12 @@ 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 = vlan_tx_tag_get(skb); - + if (vlan_tx_tag_present(skb)) { + aux.tp_vlan_tci = vlan_tx_tag_get(skb); + aux.tp_status |= TP_STATUS_VLAN_VALID; + } else { + aux.tp_vlan_tci = 0; + } put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); } |