diff options
| author | Kevin Krakauer <krakauer@google.com> | 2020-06-07 13:37:25 -0700 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2020-06-07 13:38:43 -0700 |
| commit | 32b823fcdb00a7d6eb5ddcd378f19a659edc3da3 (patch) | |
| tree | bed24f8b692caa0e24cd1351d22bb35522cbfe3e /pkg/tcpip/network/ipv4/icmp.go | |
| parent | 62603041792021f654cfb3418e9a728220feaf60 (diff) | |
netstack: parse incoming packet headers up-front
Netstack has traditionally parsed headers on-demand as a packet moves up the
stack. This is conceptually simple and convenient, but incompatible with
iptables, where headers can be inspected and mangled before even a routing
decision is made.
This changes header parsing to happen early in the incoming packet path, as soon
as the NIC gets the packet from a link endpoint. Even if an invalid packet is
found (e.g. a TCP header of insufficient length), the packet is passed up the
stack for proper stats bookkeeping.
PiperOrigin-RevId: 315179302
Diffstat (limited to 'pkg/tcpip/network/ipv4/icmp.go')
| -rw-r--r-- | pkg/tcpip/network/ipv4/icmp.go | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/pkg/tcpip/network/ipv4/icmp.go b/pkg/tcpip/network/ipv4/icmp.go index d1c3ae835..1b67aa066 100644 --- a/pkg/tcpip/network/ipv4/icmp.go +++ b/pkg/tcpip/network/ipv4/icmp.go @@ -59,6 +59,9 @@ func (e *endpoint) handleControl(typ stack.ControlType, extra uint32, pkt *stack func (e *endpoint) handleICMP(r *stack.Route, pkt *stack.PacketBuffer) { stats := r.Stats() received := stats.ICMP.V4PacketsReceived + // TODO(gvisor.dev/issue/170): ICMP packets don't have their + // TransportHeader fields set. See icmp/protocol.go:protocol.Parse for a + // full explanation. v, ok := pkt.Data.PullUp(header.ICMPv4MinimumSize) if !ok { received.Invalid.Increment() |