diff options
Diffstat (limited to 'pkg/tcpip/header/udp.go')
-rw-r--r-- | pkg/tcpip/header/udp.go | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/pkg/tcpip/header/udp.go b/pkg/tcpip/header/udp.go index ae9d167ff..f69d53314 100644 --- a/pkg/tcpip/header/udp.go +++ b/pkg/tcpip/header/udp.go @@ -130,3 +130,32 @@ func (b UDP) Encode(u *UDPFields) { binary.BigEndian.PutUint16(b[udpLength:], u.Length) binary.BigEndian.PutUint16(b[udpChecksum:], u.Checksum) } + +// SetSourcePortWithChecksumUpdate implements ChecksummableTransport. +func (b UDP) SetSourcePortWithChecksumUpdate(new uint16) { + old := b.SourcePort() + b.SetSourcePort(new) + b.SetChecksum(^checksumUpdate2ByteAlignedUint16(^b.Checksum(), old, new)) +} + +// SetDestinationPortWithChecksumUpdate implements ChecksummableTransport. +func (b UDP) SetDestinationPortWithChecksumUpdate(new uint16) { + old := b.DestinationPort() + b.SetDestinationPort(new) + b.SetChecksum(^checksumUpdate2ByteAlignedUint16(^b.Checksum(), old, new)) +} + +// UpdateChecksumPseudoHeaderAddress implements ChecksummableTransport. +func (b UDP) UpdateChecksumPseudoHeaderAddress(old, new tcpip.Address, fullChecksum bool) { + xsum := b.Checksum() + if fullChecksum { + xsum = ^xsum + } + + xsum = checksumUpdate2ByteAlignedAddress(xsum, old, new) + if fullChecksum { + xsum = ^xsum + } + + b.SetChecksum(xsum) +} |