在Ubuntu 12.04上安装logwatch (安装postfix )之前,端口25被iptables / csf阻塞
PORT STATE SERVICE 25/tcp filtered smtp
安装logwatch(安装postfix)后,现在打开端口25
PORT STATE SERVICE 25/tcp open smtp
使用csf -r重新启动CSF,但端口保持打开状态。 除TCP_ON , TCP_OUT , UDP_IN , UDP_OUT定义的端口外,是不是所有端口都被默认阻塞? 为什么端口25仍然打开?
csf.conf
TCP_IN = "22,27017,27018,27019" TCP_OUT = "53,27017,27018,27019" UDP_IN = "" UDP_OUT = "53,123"
sudo netstat -tnlp | grep:25
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN 7641/master tcp6 0 0 :::25 :::* LISTEN 7641/master
iptables -L -n -v --line-numbers
Chain INPUT (policy DROP 0 packets, 0 bytes) num pkts bytes target prot opt in out source destination 1 0 0 ACCEPT tcp -- !lo * 209.244.0.3 0.0.0.0/0 tcp dpt:53 2 0 0 ACCEPT udp -- !lo * 209.244.0.3 0.0.0.0/0 udp dpt:53 3 0 0 ACCEPT tcp -- !lo * 209.244.0.3 0.0.0.0/0 tcp spt:53 4 0 0 ACCEPT udp -- !lo * 209.244.0.3 0.0.0.0/0 udp spt:53 5 0 0 ACCEPT tcp -- !lo * 8.8.8.8 0.0.0.0/0 tcp dpt:53 6 0 0 ACCEPT udp -- !lo * 8.8.8.8 0.0.0.0/0 udp dpt:53 7 0 0 ACCEPT tcp -- !lo * 8.8.8.8 0.0.0.0/0 tcp spt:53 8 0 0 ACCEPT udp -- !lo * 8.8.8.8 0.0.0.0/0 udp spt:53 9 0 0 ACCEPT tcp -- !lo * 8.8.4.4 0.0.0.0/0 tcp dpt:53 10 0 0 ACCEPT udp -- !lo * 8.8.4.4 0.0.0.0/0 udp dpt:53 11 0 0 ACCEPT tcp -- !lo * 8.8.4.4 0.0.0.0/0 tcp spt:53 12 52 6331 ACCEPT udp -- !lo * 8.8.4.4 0.0.0.0/0 udp spt:53 13 10491 986K LOCALINPUT all -- !lo * 0.0.0.0/0 0.0.0.0/0 14 51 3795 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0 15 10278 968K INVALID tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 16 10226 965K ACCEPT all -- !lo * 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED 17 0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:22 18 44 2640 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:27017 19 0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:27018 20 0 0 ACCEPT tcp -- !lo * 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:27019 21 0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmptype 8 limit: avg 1/sec burst 5 22 0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmptype 0 limit: avg 1/sec burst 5 23 0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmptype 11 24 0 0 ACCEPT icmp -- !lo * 0.0.0.0/0 0.0.0.0/0 icmptype 3 25 8 452 LOGDROPIN all -- !lo * 0.0.0.0/0 0.0.0.0/0 Chain FORWARD (policy DROP 0 packets, 0 bytes) num pkts bytes target prot opt in out source destination Chain OUTPUT (policy DROP 0 packets, 0 bytes) num pkts bytes target prot opt in out source destination 1 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 209.244.0.3 tcp dpt:53 2 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 209.244.0.3 udp dpt:53 3 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 209.244.0.3 tcp spt:53 4 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 209.244.0.3 udp spt:53 5 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 8.8.8.8 tcp dpt:53 6 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 8.8.8.8 udp dpt:53 7 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 8.8.8.8 tcp spt:53 8 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 8.8.8.8 udp spt:53 9 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 8.8.4.4 tcp dpt:53 10 52 3614 ACCEPT udp -- * !lo 0.0.0.0/0 8.8.4.4 udp dpt:53 11 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 8.8.4.4 tcp spt:53 12 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 8.8.4.4 udp spt:53 13 7286 1342K LOCALOUTPUT all -- * !lo 0.0.0.0/0 0.0.0.0/0 14 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 tcp dpt:53 15 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 udp dpt:53 16 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 tcp spt:53 17 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 udp spt:53 18 51 3795 ACCEPT all -- * lo 0.0.0.0/0 0.0.0.0/0 19 7127 1288K INVALID tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 20 7127 1288K ACCEPT all -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate RELATED,ESTABLISHED 21 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:53 22 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:80 23 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:27017 24 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:27018 25 0 0 ACCEPT tcp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW tcp dpt:27019 26 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW udp dpt:53 27 0 0 ACCEPT udp -- * !lo 0.0.0.0/0 0.0.0.0/0 ctstate NEW udp dpt:123 28 0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmptype 0 29 0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmptype 8 30 0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmptype 11 31 0 0 ACCEPT icmp -- * !lo 0.0.0.0/0 0.0.0.0/0 icmptype 3 32 0 0 LOGDROPOUT all -- * !lo 0.0.0.0/0 0.0.0.0/0 Chain ALLOWIN (1 references) num pkts bytes target prot opt in out source destination 1 0 0 ACCEPT all -- !lo * 162.158.0.0/15 0.0.0.0/0 2 0 0 ACCEPT all -- !lo * 198.41.128.0/17 0.0.0.0/0 3 0 0 ACCEPT all -- !lo * 197.234.240.0/22 0.0.0.0/0 4 0 0 ACCEPT all -- !lo * 188.114.96.0/20 0.0.0.0/0 5 0 0 ACCEPT all -- !lo * 190.93.240.0/20 0.0.0.0/0 6 0 0 ACCEPT all -- !lo * 108.162.192.0/18 0.0.0.0/0 7 0 0 ACCEPT all -- !lo * 141.101.64.0/18 0.0.0.0/0 8 0 0 ACCEPT all -- !lo * 103.31.4.0/22 0.0.0.0/0 9 0 0 ACCEPT all -- !lo * 103.22.200.0/22 0.0.0.0/0 10 0 0 ACCEPT all -- !lo * 103.21.244.0/22 0.0.0.0/0 11 0 0 ACCEPT all -- !lo * 173.245.48.0/20 0.0.0.0/0 12 0 0 ACCEPT all -- !lo * 199.27.128.0/21 0.0.0.0/0 13 213 17445 ACCEPT all -- !lo * 59.189.154.164 0.0.0.0/0 Chain ALLOWOUT (1 references) num pkts bytes target prot opt in out source destination 1 0 0 ACCEPT all -- * !lo 0.0.0.0/0 162.158.0.0/15 2 0 0 ACCEPT all -- * !lo 0.0.0.0/0 198.41.128.0/17 3 0 0 ACCEPT all -- * !lo 0.0.0.0/0 197.234.240.0/22 4 0 0 ACCEPT all -- * !lo 0.0.0.0/0 188.114.96.0/20 5 0 0 ACCEPT all -- * !lo 0.0.0.0/0 190.93.240.0/20 6 0 0 ACCEPT all -- * !lo 0.0.0.0/0 108.162.192.0/18 7 0 0 ACCEPT all -- * !lo 0.0.0.0/0 141.101.64.0/18 8 0 0 ACCEPT all -- * !lo 0.0.0.0/0 103.31.4.0/22 9 0 0 ACCEPT all -- * !lo 0.0.0.0/0 103.22.200.0/22 10 0 0 ACCEPT all -- * !lo 0.0.0.0/0 103.21.244.0/22 11 0 0 ACCEPT all -- * !lo 0.0.0.0/0 173.245.48.0/20 12 0 0 ACCEPT all -- * !lo 0.0.0.0/0 199.27.128.0/21 13 159 53077 ACCEPT all -- * !lo 0.0.0.0/0 59.189.154.164 Chain DENYIN (1 references) num pkts bytes target prot opt in out source destination Chain DENYOUT (1 references) num pkts bytes target prot opt in out source destination Chain INVALID (2 references) num pkts bytes target prot opt in out source destination 1 0 0 INVDROP all -- * * 0.0.0.0/0 0.0.0.0/0 ctstate INVALID 2 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x3F/0x00 3 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x3F/0x3F 4 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x03/0x03 5 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x06/0x06 6 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x05/0x05 7 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x11/0x01 8 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x18/0x08 9 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x30/0x20 10 0 0 INVDROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags:! 0x17/0x02 ctstate NEW Chain INVDROP (10 references) num pkts bytes target prot opt in out source destination 1 0 0 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain LOCALINPUT (1 references) num pkts bytes target prot opt in out source destination 1 10491 986K ALLOWIN all -- !lo * 0.0.0.0/0 0.0.0.0/0 2 10278 968K DENYIN all -- !lo * 0.0.0.0/0 0.0.0.0/0 Chain LOCALOUTPUT (1 references) num pkts bytes target prot opt in out source destination 1 7286 1342K ALLOWOUT all -- * !lo 0.0.0.0/0 0.0.0.0/0 2 7127 1288K DENYOUT all -- * !lo 0.0.0.0/0 0.0.0.0/0 Chain LOGDROPIN (1 references) num pkts bytes target prot opt in out source destination 1 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:67 2 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:67 3 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:68 4 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:68 5 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:111 6 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:111 7 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:113 8 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:113 9 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpts:135:139 10 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpts:135:139 11 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:445 12 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:445 13 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:500 14 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:500 15 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:513 16 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:513 17 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:520 18 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:520 19 8 452 LOG tcp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *TCP_IN Blocked* " 20 0 0 LOG udp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *UDP_IN Blocked* " 21 0 0 LOG icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *ICMP_IN Blocked* " 22 8 452 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain LOGDROPOUT (1 references) num pkts bytes target prot opt in out source destination 1 0 0 LOG tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x17/0x02 limit: avg 30/min burst 5 LOG flags 8 level 4 prefix "Firewall: *TCP_OUT Blocked* " 2 0 0 LOG udp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 8 level 4 prefix "Firewall: *UDP_OUT Blocked* " 3 0 0 LOG icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 8 level 4 prefix "Firewall: *ICMP_OUT Blocked* " 4 0 0 DROP all -- * * 0.0.0.0/0 0.0.0.0/0
恭喜,在缓慢而耐心的质疑的影响下,你已经解决了自己的问题。 ALLOWIN链中的规则13允许来自testing客户端( 59.189.154.164 )的IP地址的所有stream量,所以当你启动一个MTA时, nmap响应从过滤(即, 你可以到达端口,但没有监听器,所以你得到一个TCP重置 )打开( 你可以到达端口,有人准备和你说话 )。
这是一个相当复杂的规则集,许多规则都没有数据包计数,因此不会为你做任何事情。 您可能会发现,在您的业务需求方面对您的防火墙规则进行全面彻底的检查对您而言是一笔不错的投资,然后再次将您重新启动。