A.iptables—A input—p tcp—s 192.168.0.2—source—port 23—j DENY
B.iptables—A input—p tcp—s 192.168.0.2—destination—port 23—j DENY
C.iptables—A input—p tcp—d 192.168.0.2—source—port 23—j DENY
D.iptables—A input—p tcp—d 192.168.0.2—destination—port 23—j DENY

A.unicode
B.IIS hacker
C.输入法漏洞
D.单用户登陆

A.22
B.21
C.79
D.80

A.22
B.21
C.79
D.80