diff options
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/skbuff.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 8c00be4d8919..93443a01ab39 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -5532,6 +5532,39 @@ int skb_mpls_pop(struct sk_buff *skb, __be16 next_proto) EXPORT_SYMBOL_GPL(skb_mpls_pop); /** + * skb_mpls_update_lse() - modify outermost MPLS header and update csum + * + * @skb: buffer + * @mpls_lse: new MPLS label stack entry to update to + * + * Expects skb->data at mac header. + * + * Returns 0 on success, -errno otherwise. + */ +int skb_mpls_update_lse(struct sk_buff *skb, __be32 mpls_lse) +{ + int err; + + if (unlikely(!eth_p_mpls(skb->protocol))) + return -EINVAL; + + err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN); + if (unlikely(err)) + return err; + + if (skb->ip_summed == CHECKSUM_COMPLETE) { + __be32 diff[] = { ~mpls_hdr(skb)->label_stack_entry, mpls_lse }; + + skb->csum = csum_partial((char *)diff, sizeof(diff), skb->csum); + } + + mpls_hdr(skb)->label_stack_entry = mpls_lse; + + return 0; +} +EXPORT_SYMBOL_GPL(skb_mpls_update_lse); + +/** * alloc_skb_with_frags - allocate skb with page frags * * @header_len: size of linear part |