The use of Firewalk

Firewalk用于判断路由器或防火墙在第四层配置策略和规则
通过分析ttl值和响应情况，可以判断目标主机后的防火墙是否允许特定端口的通信。
1.判断主机到主机间的ttl值
2.扫描端口开放情况
用法：
firewalk -d 22 23 192.168.11.1

参数：
firewalk [options] target_gateway metric
[-d 0 - 65535] destination port to use (ramping phase)
[-h] program help
[-i device] interface
[-n] do not resolve IP addresses into hostnames
[-p TCP | UDP] firewalk protocol
[-r] strict RFC adherence
[-S x - y, z] port range to scan
[-s 0 - 65535] source port
[-T 1 - 1000] packet read timeout in ms
[-t 1 - 25] IP time to live
[-v] program version
[-x 1 - 8] expire vector