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-rw-r--r--net/core/skbuff.c95
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
*
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