안녕하세요 여러분,
여기서 처음 글을 올립니다. 제 배경은 다음과 같습니다. 저는 10년 이상 리눅스 서버를 관리해 왔습니다. 약 일주일 전, 서버(Debian Bullseye)에 Discourse를 설치했습니다. 지금까지 매우 마음에 듭니다!
이제 호스트 시스템(예: 웹 서버)에 일반적인 강화 조치들을 적용하고 싶었습니다. 여기에는 nftables 규칙 세트 등이 포함됩니다. 저는 일반적으로 다음 규칙들을 사용합니다:
#!/usr/sbin/nft -f
####################
# Purge/Flush #
####################
flush ruleset
####################
# Incoming Traffic #
####################
table inet filter {
chain input {
type filter hook input priority 0; policy drop;
# Allow loopback interface
iifname lo accept
# Rate limit ICMPv4|ICMPv6 traffic
ip protocol icmp icmp type { echo-request, echo-reply, destination-unreachable, time-exceeded, parameter-problem, router-solicitation, router-advertisement } limit rate over 5/second drop
ip6 nexthdr icmpv6 icmpv6 type { destination-unreachable, packet-too-big, time-exceeded, echo-request, parameter-problem, echo-reply, nd-router-solicit, nd-router-advert, nd-neighbor-solicit, nd-neighbor-advert, ind-neighbor-solicit, ind-neighbor-advert } limit rate over 5/second drop
# Allow packets to established/related connections
ct state established,related accept
# Drop invalid connections
ct state invalid drop
# Allow ICMPv4: Ping requests | Error messages | Router selection messages
ip protocol icmp icmp type { echo-request, echo-reply, destination-unreachable, time-exceeded, parameter-problem, router-solicitation, router-advertisement } accept
# Allow ICMPv6 traffic (https://tools.ietf.org/html/rfc4890#page-18)
ip6 nexthdr icmpv6 icmpv6 type { destination-unreachable, packet-too-big, time-exceeded, echo-request, parameter-problem, echo-reply, nd-router-solicit, nd-router-advert, nd-neighbor-solicit, nd-neighbor-advert, ind-neighbor-solicit, ind-neighbor-advert } accept
# Allow SSH access on port 2222 [rate limit]
tcp dport 2222 ct state new limit rate 3/minute accept
# Allow HTTP / HTTPS traffic
tcp dport { http, https } accept
# Reject other packets
ip protocol tcp reject with tcp reset
ip6 nexthdr tcp reject with tcp reset
}
####################
# Forward Traffic #
####################
chain forward {
type filter hook forward priority 0; policy drop;
}
####################
# Outgoing Traffic #
####################
chain output {
type filter hook output priority 0; policy accept;
# Allow loopback interface
oifname lo accept
}
}
그러나 활성화한 후 Discourse가 작동하지 않게 되었습니다. 패키지가 Discourse의 Docker 설치로 전달되지 않는 것 같습니다. 특히 다음 규칙이 문제일 가능성이 높습니다:
####################
# Forward Traffic #
####################
chain forward {
type filter hook forward priority 0; policy drop;
}
하지만 이제 막 조정을 시작하기 전에, 이미 이 문제를 다뤄본 적이 있고 베이스 시스템에 대해 작동하는 방화벽 규칙이 있는 분이 있는지 여쭤보고 싶었습니다. 이러한 규칙들은 Docker 기반 Discourse 설치에 의미가 있을까요? 지금까지 저는 Docker에 대해 거의 다루어 본 적이 없습니다.
추가 정보입니다. 다음 방화벽 규칙들은 Docker(docker-ce)에 의해 자동으로 추가됩니다:
table ip nat {
chain DOCKER {
iifname "docker0" counter packets 0 bytes 0 return
iifname != "docker0" meta l4proto tcp tcp dport 443 counter packets 155 bytes 7070 dnat to 172.17.0.2:443
iifname != "docker0" meta l4proto tcp tcp dport 80 counter packets 128 bytes 6263 dnat to 172.17.0.2:80
}
chain POSTROUTING {
type nat hook postrouting priority srcnat; policy accept;
oifname != "docker0" ip saddr 172.17.0.0/16 counter packets 34 bytes 2188 masquerade
meta l4proto tcp ip saddr 172.17.0.2 ip daddr 172.17.0.2 tcp dport 443 counter packets 0 bytes 0 masquerade
meta l4proto tcp ip saddr 172.17.0.2 ip daddr 172.17.0.2 tcp dport 80 counter packets 0 bytes 0 masquerade
}
chain PREROUTING {
type nat hook prerouting priority dstnat; policy accept;
fib daddr type local counter packets 11439 bytes 550595 jump DOCKER
}
chain OUTPUT {
type nat hook output priority -100; policy accept;
ip daddr != 127.0.0.0/8 fib daddr type local counter packets 0 bytes 0 jump DOCKER
}
}
table ip filter {
chain DOCKER {
iifname != "docker0" oifname "docker0" meta l4proto tcp ip daddr 172.17.0.2 tcp dport 443 counter packets 155 bytes 7070 accept
iifname != "docker0" oifname "docker0" meta l4proto tcp ip daddr 172.17.0.2 tcp dport 80 counter packets 128 bytes 6263 accept
}
chain DOCKER-ISOLATION-STAGE-1 {
iifname "docker0" oifname != "docker0" counter packets 588 bytes 44199 jump DOCKER-ISOLATION-STAGE-2
counter packets 1187 bytes 428425 return
}
chain DOCKER-ISOLATION-STAGE-2 {
oifname "docker0" counter packets 0 bytes 0 drop
counter packets 588 bytes 44199 return
}
chain FORWARD {
type filter hook forward priority filter; policy drop;
counter packets 1187 bytes 428425 jump DOCKER-USER
counter packets 1187 bytes 428425 jump DOCKER-ISOLATION-STAGE-1
oifname "docker0" ct state related,established counter packets 316 bytes 370893 accept
oifname "docker0" counter packets 283 bytes 13333 jump DOCKER
iifname "docker0" oifname != "docker0" counter packets 588 bytes 44199 accept
iifname "docker0" oifname "docker0" counter packets 0 bytes 0 accept
}
chain DOCKER-USER {
counter packets 1187 bytes 428425 return
}
chain INPUT {
type filter hook input priority filter; policy accept;
}
}
감사합니다
