网络层隧道1.IPv6隧道2.ICMP隧道ICMP隧道工具有PingTunnel，icmptunnel，lcmpsh,powershellicmp等A.icmpshB.pingtunnelicmpshhttps://github.com/bdamele/icmpsh:::infosysctl-wnet.ipv4.icmp_echo_ignore_all=1./icmpshm.pyIP(公网)IP(内网)icmpsh.exe-t公网I