iptables 规则整理

[root@xiaorui ~]# iptables -V
iptables v1.4.7
[root@xiaorui ~]# iptables -h
iptables v1.4.7

Usage: iptables -[ACD] chain rule-specification [options]
       iptables -I chain [rulenum] rule-specification [options]
       iptables -R chain rulenum rule-specification [options]
       iptables -D chain rulenum [options]
       iptables -[LS] [chain [rulenum]] [options]
       iptables -[FZ] [chain] [options]
       iptables -[NX] chain
       iptables -E old-chain-name new-chain-name
       iptables -P chain target [options]
       iptables -h (print this help information)

Commands:
Either long or short options are allowed.
  --append  -A chain            Append to chain
  --check   -C chain            Check for the existence of a rule
  --delete  -D chain            Delete matching rule from chain
  --delete  -D chain rulenum
                                Delete rule rulenum (1 = first) from chain
  --insert  -I chain [rulenum]
                                Insert in chain as rulenum (default 1=first)
  --replace -R chain rulenum
                                Replace rule rulenum (1 = first) in chain
  --list    -L [chain [rulenum]]
                                List the rules in a chain or all chains
  --list-rules -S [chain [rulenum]]
                                Print the rules in a chain or all chains
  --flush   -F [chain]          Delete all rules in  chain or all chains
  --zero    -Z [chain [rulenum]]
                                Zero counters in chain or all chains
  --new     -N chain            Create a new user-defined chain
  --delete-chain
            -X [chain]          Delete a user-defined chain
  --policy  -P chain target
                                Change policy on chain to target
  --rename-chain
            -E old-chain new-chain
                                Change chain name, (moving any references)
Options:
[!] --proto     -p proto        protocol: by number or name, eg. `tcp‘
[!] --source    -s address[/mask][...]
                                source specification
[!] --destination -d address[/mask][...]
                                destination specification
[!] --in-interface -i input name[+]
                                network interface name ([+] for wildcard)
 --jump -j target
                                target for rule (may load target extension)
  --goto      -g chain
                              jump to chain with no return
  --match       -m match
                                extended match (may load extension)
  --numeric     -n              numeric output of addresses and ports
[!] --out-interface -o output name[+]
                                network interface name ([+] for wildcard)
  --table       -t table        table to manipulate (default: `filter‘)
  --verbose     -v              verbose mode
  --line-numbers                print line numbers when listing
  --exact       -x              expand numbers (display exact values)
[!] --fragment  -f              match second or further fragments only
  --modprobe=<command>          try to insert modules using this command
  --set-counters PKTS BYTES     set the counter during insert/append
[!] --version   -V              print package version.

[root@xiaorui ~]# iptables -F
[root@xiaorui ~]# iptables --flush
提示：以上两条命令等价
[root@xiaorui ~]# iptables -X
[root@xiaorui ~]# iptables --delete-chain
提示：以上两条命令等价
[root@xiaorui ~]# iptables -Z
[root@xiaorui ~]# iptables --zero
提示：以上两条命令等价
[root@xiaorui ~]# iptables -L -n
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

[root@xiaorui ~]# netstat -lntup|grep ssh
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      2073/sshd           
tcp        0      0 :::22                       :::*                        LISTEN      2073/sshd 

语法：
Usage: iptables -t [table] -[AD] chain rule-specification [options]
具体命令：
[root@xiaorui ~]# iptables -A INPUT -p tcp --dport 22 -j DROP
[root@xiaorui ~]# iptables -t filter -A INPUT -p tcp --dport 22 -j DROP
注：
1、iptables默认用的就是filter表，因此，以上两条命令等价
2、其中的INPUT DROP要大写
3、--jump  -j target
   target for rule(may load target extension)
   基本的处理行为：ACCEPT（接受）、DROP（丢弃）、REJECT（拒绝）
   比较：DROP好于REJECT
4、命令行执行的规则，仅仅在内存里临时生效

[root@ipt ~]# iptables -F
[root@ipt ~]# iptables -X
[root@ipt ~]# iptables -Z
[root@ipt ~]# iptables -A INPUT -p tcp  --dport 22 -s 10.0.0.0/24  -j ACCEPT
[root@ipt ~]# iptables -A INPUT -i lo -j ACCEPT
[root@ipt ~]# iptables -A INPUT -o lo -j ACCEPT  
[root@ipt ~]# iptables -A OUTPUT -o lo -j ACCEPT  

iptables -A INPUT -s 124.43.62.96/27 -p all -j ACCEPT
iptables -A INPUT -s 192.168.1.0/24 -p all -j ACCEPT
iptables -A INPUT -s 10.0.0.0/24 -p all -j ACCEPT    
iptables -A INPUT -s 203.83.24.0/24 -p all -j ACCEPT
iptables -A INPUT -s 201.82.34.0/24 -p all -j ACCEPT

iptables -A INPUT -p icmp --icmp-type 8  -j ACCEPT

#others RELATED ftp协议
#允许关联的状态包
iptables -A INPUT  -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

client(config)#int eth0
client(config-if)#ip add 10.1.34.81 255.255.255.0
client(config-if)#int eth1
client(config-if)#ip add 110.233.24.96 255.255.255.224
client(config)#ip route 0.0.0.0 0.0.0.0 10.1.32.1
client(config)#ip route 110.233.24.96/27 eth1

lsmod |egrep "nat|filter"
modprobe ip_tables
modprobe iptable_filter
modprobe iptable_nat
modprobe ip_conntrack
modprobe ip_conntrack_ftp
modprobe ip_nat_ftp
modprobe ipt_state