netfilter: nf_tables: add nft_payload_rebuild_vlan_hdr()

Wrap the code to rebuild the ethernet + vlan header into a function.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Florian Westphal <fw@strlen.de>
This commit is contained in:
Pablo Neira Ayuso 2019-10-31 15:51:22 +01:00
parent f41f72d09e
commit 8dfd8b09aa

View File

@ -23,6 +23,19 @@
#include <linux/ip.h>
#include <linux/ipv6.h>
static bool nft_payload_rebuild_vlan_hdr(const struct sk_buff *skb, int mac_off,
struct vlan_ethhdr *veth)
{
if (skb_copy_bits(skb, mac_off, veth, ETH_HLEN))
return false;
veth->h_vlan_proto = skb->vlan_proto;
veth->h_vlan_TCI = htons(skb_vlan_tag_get(skb));
veth->h_vlan_encapsulated_proto = skb->protocol;
return true;
}
/* add vlan header into the user buffer for if tag was removed by offloads */
static bool
nft_payload_copy_vlan(u32 *d, const struct sk_buff *skb, u8 offset, u8 len)
@ -35,13 +48,9 @@ nft_payload_copy_vlan(u32 *d, const struct sk_buff *skb, u8 offset, u8 len)
if (offset < VLAN_ETH_HLEN) {
u8 ethlen = len;
if (skb_copy_bits(skb, mac_off, &veth, ETH_HLEN))
if (!nft_payload_rebuild_vlan_hdr(skb, mac_off, &veth))
return false;
veth.h_vlan_proto = skb->vlan_proto;
veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb));
veth.h_vlan_encapsulated_proto = skb->protocol;
if (offset + len > VLAN_ETH_HLEN)
ethlen -= offset + len - VLAN_ETH_HLEN;