bash - 在 iptables 的文件中插入行

Question

我使用 bash 文件，我想在 iptables 的文件中插入和获取行

# Firewall configuration written by system-config-firewall
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
{My Line Here}
-A INPUT -m state --state NEW -m udp -p udp --dport 5353 -d 224.0.0.251 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT

将 {My line here} 替换为

-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT

1. 然后我想找到并获取防火墙开放端口并显示它们

Answer 1

sed 's/-A INPUT -i lo -j ACCEPT/-A INPUT -i lo -j ACCEPT\n-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT/g' <filename> > temp ; mv temp <filename>

<filename>用实际文件替换。这仅在前一行是-A INPUT -i lo -j ACCEPT