스크립트 [중복]에서 시스템에 iptables가 설정되어 있는지 확인하세요.

Bash로 스크립트를 작성 중인데 iptables가 설정되어 있는지 확인해야 합니다. 다음이 있습니다.

if [ `iptables-save | grep '^\-' | wc -l` > 0 ]
then
    echo "Iptables already set, skipping..........!"
else
    Here the iptables get set

하지만 예상대로 작동하지 않습니다 ...

질문:

나는 이것을 했고 iptables-save이것을 만들었습니다:

$iptables-save
# Generated by iptables-save v1.6.0 on Tue Oct 16 02:48:41 2018
*filter
:INPUT ACCEPT [2:266]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [2:116]
COMMIT
# Completed on Tue Oct 16 02:48:41 2018

따라서 테스트를 실행하면 다음과 같이 설정되어 있음을 알 수 있습니다.

(root@notemDEB78)-(03:12:20)-(/home/something78/Bash_Programming_2018)
$s.sh
Iptables already set....skipping!!!!!
(root@notemDEB78)-(03:12:25)-(/home/something78/Bash_Programming_2018)
$iptables -L
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@notemDEB78)-(03:16:41)-(/home/something78/Bash_Programming_2018)
$iptables-save | grep '^\-' | wc -l
0

질문:

• iptables가 설정되어 있는데 분명히 설정되지 않은 이유는 무엇입니까?

• iptables설정되어 있는지 확인하는 더 좋고 효율적인 방법이 있습니까 ? 내 시스템은 다음과 같습니다.Debian 9

  bash -version GNU bash, 버전 4.4.12(1)-릴리스(x86_64-pc-linux-gnu) 저작권 (C) 2016 Free Software Foundation, Inc. 라이센스 GPLv3+: GNU GPL 버전 3 이상http://gnu.org/licenses/gpl.html

가능한 중복에 관해서는 다음과 같습니다.

이 질문은 또한 bash의 스크립트에 iptables가 설정되어 있는지 확인하는 더 좋은 방법이 있는지 묻습니다.

편집하다:

제가 말하는 설정은 다음과 같이 iptables의 설정을 참조합니다.

if [[ `iptables-save | grep '^\-' | wc -l` > 0 ]]
    then
        echo "Iptables already set....skipping!!!!!"
    else
        if [ "$PORT" = "" ]
        then
            echo "Port not set for iptables exiting"
            echo -n "Setting port now, insert portnumber: "
            read port
            PORT=$port
        fi
        if [ ! -f /etc/iptables.test.rules ]
        then
            touch /etc/iptables.test.rules
        else
            cat /dev/null > /etc/iptables.test.rules
        fi

        cat << EOT >> /etc/iptables.test.rules
        *filter

        # Allows all loopback (lo0) traffic and drop all traffic to 127/8 that doesn't use lo0
        -A INPUT -i lo -j ACCEPT
        -A INPUT ! -i lo -d 127.0.0.0/8 -j REJECT

        # Accepts all established inOAUTH_TOKEN=d6637f7ccf109a0171a2f55d21b6ca43ff053616bound connections
        -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

        # Allows all outbound traffic
        # You could modify this to only allow certain traffic
        -A OUTPUT -j ACCEPT

        # Allows HTTP and HTTPS connections from anywhere (the normal ports for websites)
        -A INPUT -p tcp --dport 80 -j ACCEPT
        -A INPUT -p tcp --dport 443 -j ACCEPT

        # Allows SSH connections
        # The --dport number is the same as in /etc/ssh/sshd_config
        -A INPUT -p tcp -m state --state NEW --dport $PORT -j ACCEPT

        # Now you should read up on iptables rules and consider whether ssh access
        # for everyone is really desired. Most likely you will only allow access from certain IPs.

        # Allow ping
        #  note that blocking other types of icmp packets is considered a bad idea by some
        #  remove -m icmp --icmp-type 8 from this line to allow all kinds of icmp:
        #  https://security.stackexchange.com/questions/22711
        -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT

        # log iptables denied calls (access via dmesg command)
        -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7

        # Reject all other inbound - default deny unless explicitly allowed policy:
        -A INPUT -j REJECT
        -A FORWARD -j REJECT

        COMMIT
EOT
        sed "s/^[ \t]*//" -i /etc/iptables.test.rules ## remove tabs and spaces
        /sbin/iptables-restore < /etc/iptables.test.rules || echo "iptables-restore failed"; exit 127
        /sbin/iptables-save > /etc/iptables.up.rules || echo "iptables-save failed"; exit 127
        printf "#!/bin/bash\n/sbin/iptables-restore < /etc/iptables.up.rules" > /etc/network/if-pre-up.d/iptables ## create a script to run iptables on startup
        chmod +x /etc/network/if-pre-up.d/iptables || echo "cmod +x failed"; exit 127
    fi