Method Serve

ingress/icmp_darwin.go:198–232

Serve listens for responses to the requests until context is done

(ctx context.Context)

// Serve listens for responses to the requests until context is done
func (ip *icmpProxy) Serve(ctx context.Context) error {
	go func() {
		<-ctx.Done()
		ip.conn.Close()
	}()
	go func() {
		ip.srcFunnelTracker.ScheduleCleanup(ctx, ip.idleTimeout)
	}()
	buf := make([]byte, mtu)
	icmpDecoder := packet.NewICMPDecoder()
	for {
		n, from, err := ip.conn.ReadFrom(buf)
		if err != nil {
			return err
		}
		reply, err := parseReply(from, buf[:n])
		if err != nil {
			ip.logger.Debug().Err(err).Str("dst", from.String()).Msg("Failed to parse ICMP reply, continue to parse as full packet")
			// In unit test, we found out when the listener listens on 0.0.0.0, the socket reads the full packet after
			// the second reply
			if err := ip.handleFullPacket(ctx, icmpDecoder, buf[:n]); err != nil {
				ip.logger.Debug().Err(err).Str("dst", from.String()).Msg("Failed to parse ICMP reply as full packet")
			}
			continue
		}
		if !isEchoReply(reply.msg) {
			ip.logger.Debug().Str("dst", from.String()).Msgf("Drop ICMP %s from reply", reply.msg.Type)
			continue
		}
		if err := ip.sendReply(ctx, reply); err != nil {
			ip.logger.Debug().Err(err).Str("dst", from.String()).Msg("Failed to send ICMP reply")
			continue
		}
	}
}

func (ip *icmpProxy) handleFullPacket(ctx context.Context, decoder *packet.ICMPDecoder, rawPacket []byte) error {
	icmpPacket, err := decoder.Decode(packet.RawPacket{Data: rawPacket})