SKB_CHECKSUM_COMPLET(9) Linux Networking SKB_CHECKSUM_COMPLET(9)NAMEskb_checksum_complete - Calculate checksum of an entire packet
SYNOPSIS
__sum16 skb_checksum_complete(struct sk_buff * skb);
ARGUMENTS
skb
packet to process
DESCRIPTION
This function calculates the checksum over the entire packet plus the
value of skb->csum. The latter can be used to supply the checksum of a
pseudo header as used by TCP/UDP. It returns the checksum.
For protocols that contain complete checksums such as ICMP/TCP/UDP,
this function can be used to verify that checksum on received packets.
In that case the function should return zero if the checksum is
correct. In particular, this function will return zero if
skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
hardware has already verified the correctness of the checksum.
COPYRIGHTKernel Hackers Manual 2.6. November 2013 SKB_CHECKSUM_COMPLET(9)