Checksum action in tc(8)

NAME
csum - checksum update action

SYNOPSIS
tc ... action csum UPDATE
UPDATE := TARGET [ UPDATE ]
TARGET := { ip4h | icmp | igmp | tcp | udp | udplite | SWEETS }
SWEETS := { and | or | + }

DESCRIPTION
The csum action triggers checksum recalculation of specified packet headers. It is commonly used after packet editing using the pedit action to fix for then incorrect checksums.

OPTIONS

TARGET
    Specify which headers to update: IPv4 header (ip4h), ICMP header (icmp), IGMP header (igmp), TCP header (tcp), UDP header (udp) or UDPLite header (udplite).

SWEETS
    These are merely syntactic sugar and ignored internally.

SEE ALSO
tc(8), tc-pedit(8)