diff options
Diffstat (limited to 'pkg/tcpip/network/ipv4')
| -rw-r--r-- | pkg/tcpip/network/ipv4/icmp.go | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/pkg/tcpip/network/ipv4/icmp.go b/pkg/tcpip/network/ipv4/icmp.go index 9cb81245a..770f56c3d 100644 --- a/pkg/tcpip/network/ipv4/icmp.go +++ b/pkg/tcpip/network/ipv4/icmp.go @@ -72,7 +72,24 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V received.Invalid.Increment() return } + + // Only send a reply if the checksum is valid. + wantChecksum := h.Checksum() + // Reset the checksum field to 0 to can calculate the proper + // checksum. We'll have to reset this before we hand the packet + // off. + h.SetChecksum(0) + gotChecksum := ^header.ChecksumVV(vv, 0 /* initial */) + if gotChecksum != wantChecksum { + // It's possible that a raw socket expects to receive this. + h.SetChecksum(wantChecksum) + e.dispatcher.DeliverTransportPacket(r, header.ICMPv4ProtocolNumber, netHeader, vv) + received.Invalid.Increment() + return + } + // It's possible that a raw socket expects to receive this. + h.SetChecksum(wantChecksum) e.dispatcher.DeliverTransportPacket(r, header.ICMPv4ProtocolNumber, netHeader, vv) vv := vv.Clone(nil) |