diff options
Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r-- | net/core/skbuff.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index d11bbe0da355..c906c5f4bf69 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -4163,6 +4163,101 @@ int skb_ensure_writable(struct sk_buff *skb, int write_len) } EXPORT_SYMBOL(skb_ensure_writable); +/* remove VLAN header from packet and update csum accordingly. */ +static int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci) +{ + struct vlan_hdr *vhdr; + unsigned int offset = skb->data - skb_mac_header(skb); + int err; + + __skb_push(skb, offset); + err = skb_ensure_writable(skb, VLAN_ETH_HLEN); + if (unlikely(err)) + goto pull; + + skb_postpull_rcsum(skb, skb->data + (2 * ETH_ALEN), VLAN_HLEN); + + vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN); + *vlan_tci = ntohs(vhdr->h_vlan_TCI); + + memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN); + __skb_pull(skb, VLAN_HLEN); + + vlan_set_encap_proto(skb, vhdr); + skb->mac_header += VLAN_HLEN; + + if (skb_network_offset(skb) < ETH_HLEN) + skb_set_network_header(skb, ETH_HLEN); + + skb_reset_mac_len(skb); +pull: + __skb_pull(skb, offset); + + return err; +} + +int skb_vlan_pop(struct sk_buff *skb) +{ + u16 vlan_tci; + __be16 vlan_proto; + int err; + + if (likely(vlan_tx_tag_present(skb))) { + skb->vlan_tci = 0; + } else { + if (unlikely((skb->protocol != htons(ETH_P_8021Q) && + skb->protocol != htons(ETH_P_8021AD)) || + skb->len < VLAN_ETH_HLEN)) + return 0; + + err = __skb_vlan_pop(skb, &vlan_tci); + if (err) + return err; + } + /* move next vlan tag to hw accel tag */ + if (likely((skb->protocol != htons(ETH_P_8021Q) && + skb->protocol != htons(ETH_P_8021AD)) || + skb->len < VLAN_ETH_HLEN)) + return 0; + + vlan_proto = skb->protocol; + err = __skb_vlan_pop(skb, &vlan_tci); + if (unlikely(err)) + return err; + + __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci); + return 0; +} +EXPORT_SYMBOL(skb_vlan_pop); + +int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci) +{ + if (vlan_tx_tag_present(skb)) { + unsigned int offset = skb->data - skb_mac_header(skb); + int err; + + /* __vlan_insert_tag expect skb->data pointing to mac header. + * So change skb->data before calling it and change back to + * original position later + */ + __skb_push(skb, offset); + err = __vlan_insert_tag(skb, skb->vlan_proto, + vlan_tx_tag_get(skb)); + if (err) + return err; + skb->protocol = skb->vlan_proto; + skb->mac_len += VLAN_HLEN; + __skb_pull(skb, offset); + + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->csum = csum_add(skb->csum, csum_partial(skb->data + + (2 * ETH_ALEN), VLAN_HLEN, 0)); + } + __vlan_hwaccel_put_tag(skb, vlan_proto, vlan_tci); + return 0; +} +EXPORT_SYMBOL(skb_vlan_push); + /** * alloc_skb_with_frags - allocate skb with page frags * |