Ubuntu的默认防火墙管理工具是ufw,它是一个通过Python实现的工具,最终也是转换为iptables命令实现防火墙规则过滤的。 但有一点比较令人讨厌的是,ufw默认启用了非常多的规则,且配置文件非常不便于配置。 而对于习惯于直接通过iptables指令来设置防火墙规则的管理员,RHEL的iptables脚本管理方式就非常的干净利落。
但是直接将RHEL上的iptables脚本拿到Ubuntu下,是无法正常运行的,需要做很多的修改。
以下是相关步骤:
1.创建配置文件iptables-conf $ sudo mkdir /etc/sysconfig $ sudo vim /etc/sysconfig/iptables-config
# Load additional iptables modules (nat helpers) # Default: -none- # Space separated list of nat helpers (e.g. 'ip_nat_ftp ip_nat_irc'), which # are loaded after the firewall rules are applied. Options for the helpers are # stored in /etc/modprobe.conf. IPTABLES_MODULES="" # Unload modules on restart and stop # Value: yes|no, default: yes # This option has to be 'yes' to get to a sane state for a firewall # restart or stop. Only set to 'no' if there are problems unloading netfilter # modules. IPTABLES_MODULES_UNLOAD="yes" # Save current firewall rules on stop. # Value: yes|no, default: no # Saves all firewall rules to /etc/sysconfig/iptables if firewall gets stopped # (e.g. on system shutdown). IPTABLES_SAVE_ON_STOP="no" # Save current firewall rules on restart. # Value: yes|no, default: no # Saves all firewall rules to /etc/sysconfig/iptables if firewall gets # restarted. IPTABLES_SAVE_ON_RESTART="no" # Save (and restore) rule and chain counter. # Value: yes|no, default: no # Save counters for rules and chains to /etc/sysconfig/iptables if # 'service iptables save' is called or on stop or restart if SAVE_ON_STOP or # SAVE_ON_RESTART is enabled. IPTABLES_SAVE_COUNTER="no" # Numeric status output # Value: yes|no, default: yes # Print IP addresses and port numbers in numeric format in the status output. IPTABLES_STATUS_NUMERIC="yes" # Verbose status output # Value: yes|no, default: yes # Print info about the number of packets and bytes plus the "input-" and # "outputdevice" in the status output. IPTABLES_STATUS_VERBOSE="no" # Status output with numbered lines # Value: yes|no, default: yes # Print a counter/number for every rule in the status output. IPTABLES_STATUS_LINENUMBERS="yes"
2.创建规则命令文件iptables(以我的Blog为例) $ sudo vim /etc/sysconfig/iptables
*filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [4336605:3237430358] :OUTPUT ACCEPT [19418758:35598823868] -A INPUT -i lo -j ACCEPT -A INPUT -s 10.10.10.0/255.255.255.0 -j ACCEPT -A INPUT -p gre -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 47 -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 1723 -j ACCEPT -A INPUT -p udp -m state --state NEW -m udp --dport 1194 -j ACCEPT -A INPUT -p icmp -m icmp --icmp-type any -j ACCEPT -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p udp -m udp --dport 53 -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 443 -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 80 -j ACCEPT -A INPUT -j REJECT --reject-with icmp-host-prohibited COMMIT
3.创建经过修改过后得以成功执行的管理服务脚本: $ sudo touch /etc/init.d/iptables $ sudo chmod +x /etc/init.d/iptables $ sudo vim /etc/init.d/iptables
#!/bin/bash # # iptables Start iptables firewall # # chkconfig: 2345 08 92 # description: Starts, stops and saves iptables firewall # # config: /etc/sysconfig/iptables # config: /etc/sysconfig/iptables-config # Source function library. . /lib/lsb/init-functions IPTABLES=iptables IPTABLES_DATA=/etc/sysconfig/$IPTABLES IPTABLES_CONFIG=/etc/sysconfig/${IPTABLES}-config IPV=${IPTABLES%tables} # ip for ipv4 | ip6 for ipv6 PROC_IPTABLES_NAMES=/proc/net/${IPV}_tables_names VAR_SUBSYS_IPTABLES=/var/lock/subsys/$IPTABLES if [ ! -x /sbin/$IPTABLES ]; then log_failure_msg $"/sbin/$IPTABLES does not exist." exit 0 fi if lsmod 2>/dev/null | grep -q ipchains ; then log_failure_msg $"ipchains and $IPTABLES can not be used together." exit 0 fi # Old or new modutils /sbin/modprobe --version 2>&1 | grep -q module-init-tools \ && NEW_MODUTILS=1 \ || NEW_MODUTILS=0 # Default firewall configuration: IPTABLES_MODULES="" IPTABLES_MODULES_UNLOAD="yes" IPTABLES_SAVE_ON_STOP="no" IPTABLES_SAVE_ON_RESTART="no" IPTABLES_SAVE_COUNTER="no" IPTABLES_STATUS_NUMERIC="yes" # Load firewall configuration. [ -f "$IPTABLES_CONFIG" ] && . "$IPTABLES_CONFIG" rmmod_r() { # Unload module with all referring modules. # At first all referring modules will be unloaded, then the module itself. local mod=$1 local ret=0 local ref= # Get referring modules. # New modutils have another output format. [ $NEW_MODUTILS = 1 ] \ && ref=`lsmod | awk "/^${mod}/ { print \\\$4; }" | tr ',' ' '` \ || ref=`lsmod | grep ^${mod} | cut -d "[" -s -f 2 | cut -d "]" -s -f 1` # recursive call for all referring modules for i in $ref; do rmmod_r $i let ret+=$?; done # Unload module. # The extra test is for 2.6: The module might have autocleaned, # after all referring modules are unloaded. if grep -q "^${mod}" /proc/modules ; then modprobe -r $mod > /dev/null 2>&1 let ret+=$?; fi return $ret } flush_n_delete() { # Flush firewall rules and delete chains. [ -e "$PROC_IPTABLES_NAMES" ] || return 1 # Check if firewall is configured (has tables) tables=`cat $PROC_IPTABLES_NAMES 2>/dev/null` [ -z "$tables" ] && return 1 log_daemon_msg $"Flushing firewall rules: " ret=0 # For all tables for i in $tables; do # Flush firewall rules. $IPTABLES -t $i -F; let ret+=$?; # Delete firewall chains. $IPTABLES -t $i -X; let ret+=$?; # Set counter to zero. $IPTABLES -t $i -Z; let ret+=$?; done [ $ret -eq 0 ] && log_end_msg 0 || log_end_msg 1 echo return $ret } set_policy() { # Set policy for configured tables. policy=$1 # Check if iptable module is loaded [ ! -e "$PROC_IPTABLES_NAMES" ] && return 1 # Check if firewall is configured (has tables) tables=`cat $PROC_IPTABLES_NAMES 2>/dev/null` [ -z "$tables" ] && return 1 log_daemon_msg $"Setting chains to policy $policy: " ret=0 for i in $tables; do log_daemon_msg "$i " case "$i" in raw) $IPTABLES -t raw -P PREROUTING $policy \ && $IPTABLES -t raw -P OUTPUT $policy \ || let ret+=1 ;; filter) $IPTABLES -t filter -P INPUT $policy \ && $IPTABLES -t filter -P OUTPUT $policy \ && $IPTABLES -t filter -P FORWARD $policy \ || let ret+=1 ;; nat) $IPTABLES -t nat -P PREROUTING $policy \ && $IPTABLES -t nat -P POSTROUTING $policy \ && $IPTABLES -t nat -P OUTPUT $policy \ || let ret+=1 ;; mangle) $IPTABLES -t mangle -P PREROUTING $policy \ && $IPTABLES -t mangle -P POSTROUTING $policy \ && $IPTABLES -t mangle -P INPUT $policy \ && $IPTABLES -t mangle -P OUTPUT $policy \ && $IPTABLES -t mangle -P FORWARD $policy \ || let ret+=1 ;; *) let ret+=1 ;; esac done [ $ret -eq 0 ] && log_end_msg 0 || log_end_msg 1 echo return $ret } start() { # Do not start if there is no config file. [ -f "$IPTABLES_DATA" ] || return 1 log_daemon_msg $"Applying $IPTABLES firewall rules: " OPT= [ "x$IPTABLES_SAVE_COUNTER" = "xyes" ] && OPT="-c" $IPTABLES-restore $OPT $IPTABLES_DATA if [ $? -eq 0 ]; then log_end_msg 0; echo else log_end_msg 1; echo; return 1 fi # Load additional modules (helpers) if [ -n "$IPTABLES_MODULES" ]; then log_daemon_msg $"Loading additional $IPTABLES modules: " ret=0 for mod in $IPTABLES_MODULES; do log_daemon_msg "$mod " modprobe $mod > /dev/null 2>&1 let ret+=$?; done [ $ret -eq 0 ] && log_end_msg 0 || log_end_msg 1 echo fi touch $VAR_SUBSYS_IPTABLES return $ret } stop() { # Do not stop if iptables module is not loaded. [ -e "$PROC_IPTABLES_NAMES" ] || return 1 flush_n_delete set_policy ACCEPT if [ "x$IPTABLES_MODULES_UNLOAD" = "xyes" ]; then log_daemon_msg $"Unloading $IPTABLES modules: " ret=0 rmmod_r ${IPV}_tables let ret+=$?; rmmod_r ${IPV}_conntrack let ret+=$?; [ $ret -eq 0 ] && log_end_msg 0 || log_end_msg 1 echo fi rm -f $VAR_SUBSYS_IPTABLES return $ret } save() { # Check if iptable module is loaded [ ! -e "$PROC_IPTABLES_NAMES" ] && return 1 # Check if firewall is configured (has tables) tables=`cat $PROC_IPTABLES_NAMES 2>/dev/null` [ -z "$tables" ] && return 1 log_daemon_msg $"Saving firewall rules to $IPTABLES_DATA: " OPT= [ "x$IPTABLES_SAVE_COUNTER" = "xyes" ] && OPT="-c" ret=0 TMP_FILE=`/bin/mktemp -q /tmp/$IPTABLES.XXXXXX` \ && chmod 600 "$TMP_FILE" \ && $IPTABLES-save $OPT > $TMP_FILE 2>/dev/null \ && size=`stat -c '%s' $TMP_FILE` && [ $size -gt 0 ] \ || ret=1 if [ $ret -eq 0 ]; then if [ -e $IPTABLES_DATA ]; then cp -f $IPTABLES_DATA $IPTABLES_DATA.save \ && chmod 600 $IPTABLES_DATA.save \ || ret=1 fi if [ $ret -eq 0 ]; then cp -f $TMP_FILE $IPTABLES_DATA \ && chmod 600 $IPTABLES_DATA \ || ret=1 fi fi [ $ret -eq 0 ] && log_end_msg 0 || log_end_msg 1 echo rm -f $TMP_FILE return $ret } status() { tables=`cat $PROC_IPTABLES_NAMES 2>/dev/null` # Do not print status if lockfile is missing and iptables modules are not # loaded. # Check if iptable module is loaded if [ ! -f "$VAR_SUBSYS_IPTABLES" -a -z "$tables" ]; then log_daemon_msg $"Firewall is stopped." return 1 fi # Check if firewall is configured (has tables) if [ ! -e "$PROC_IPTABLES_NAMES" ]; then log_daemon_msg $"Firewall is not configured. " return 1 fi if [ -z "$tables" ]; then log_daemon_msg $"Firewall is not configured. " return 1 fi NUM= [ "x$IPTABLES_STATUS_NUMERIC" = "xyes" ] && NUM="-n" VERBOSE= [ "x$IPTABLES_STATUS_VERBOSE" = "xyes" ] && VERBOSE="--verbose" COUNT= [ "x$IPTABLES_STATUS_LINENUMBERS" = "xyes" ] && COUNT="--line-numbers" for table in $tables; do log_daemon_msg $"Table: $table" $IPTABLES -t $table --list $NUM $VERBOSE $COUNT && echo done return 0 } restart() { [ "x$IPTABLES_SAVE_ON_RESTART" = "xyes" ] && save stop start } case "$1" in start) stop start RETVAL=$? ;; stop) [ "x$IPTABLES_SAVE_ON_STOP" = "xyes" ] && save stop RETVAL=$? ;; restart) restart RETVAL=$? ;; condrestart) [ -e "$VAR_SUBSYS_IPTABLES" ] && restart RETVAL=$? ;; status) status RETVAL=$? ;; panic) flush_n_delete set_policy DROP RETVAL=$? ;; save) save RETVAL=$? ;; *) log_action_msg $"Usage: $0 {start|stop|restart|condrestart|status|panic|save}" exit 1 ;; esac exit $RETVAL