Docker - 可从外部访问的暴露端口 - iptables 规则被忽略

Question

我有一个 docker 容器运行如下：

 docker run --name some_container_1 -p 8080:80 -d some_image

哪个工作正常。容器将它的端口 80 公开到 8080，并且可以从本地主机访问。

然而，出于某种原因，它完全忽略了 INPUT iptables 规则，并且也可以从外部访问。

如何限制对我的 Docker 容器的访问，只允许 ie IP 123.456.789.0 从外部访问它？

谢谢。

---

须藤 iptables -L -n -v --line-numbers

Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
num   pkts bytes target     prot opt in     out     source               destination         
1        0     0 ACCEPT     all  --  lo     *       0.0.0.0/0            0.0.0.0/0           
2      365 23380 ACCEPT     all  --  *      *       0.0.0.0/0            0.0.0.0/0            state RELATED,ESTABLISHED
3        0     0 ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0            tcp dpt:22
4        7   788 LOG        all  --  *      *       0.0.0.0/0            0.0.0.0/0            limit: avg 5/min burst 5 LOG flags 0 level 7 prefix "iptables denied: "
5        7   788 DROP       all  --  *      *       0.0.0.0/0            0.0.0.0/0           

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
num   pkts bytes target     prot opt in     out     source               destination         
1       24  1524 DOCKER     all  --  *      docker0  0.0.0.0/0            0.0.0.0/0           
2        0     0 ACCEPT     all  --  *      docker0  0.0.0.0/0            0.0.0.0/0            ctstate RELATED,ESTABLISHED
3       15 13320 ACCEPT     all  --  docker0 !docker0  0.0.0.0/0            0.0.0.0/0           
4        0     0 ACCEPT     all  --  docker0 docker0  0.0.0.0/0            0.0.0.0/0           

Chain OUTPUT (policy ACCEPT 204 packets, 21792 bytes)
num   pkts bytes target     prot opt in     out     source               destination         

Chain DOCKER (1 references)
num   pkts bytes target     prot opt in     out     source               destination         
1       24  1524 ACCEPT     tcp  --  !docker0 docker0  0.0.0.0/0            172.17.0.2           tcp dpt:80

---

须藤 iptables-save

# Generated by iptables-save v1.4.21 on Wed Apr  8 23:37:43 2015
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [100:16642]
:DOCKER - [0:0]
-A INPUT -i lo -j ACCEPT
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
-A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7
-A INPUT -j DROP
-A FORWARD -o docker0 -j DOCKER
-A FORWARD -o docker0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
-A DOCKER -d 172.17.0.2/32 ! -i docker0 -o docker0 -p tcp -m tcp --dport 80 -j ACCEPT
COMMIT
# Completed on Wed Apr  8 23:37:43 2015
# Generated by iptables-save v1.4.21 on Wed Apr  8 23:37:43 2015
*nat
:PREROUTING ACCEPT [13:2206]
:INPUT ACCEPT [1:64]
:OUTPUT ACCEPT [4:268]
:POSTROUTING ACCEPT [4:268]
:DOCKER - [0:0]
-A PREROUTING -m addrtype --dst-type LOCAL -j DOCKER
-A OUTPUT ! -d 127.0.0.0/8 -m addrtype --dst-type LOCAL -j DOCKER
-A POSTROUTING -s 172.17.0.0/16 ! -o docker0 -j MASQUERADE
-A POSTROUTING -s 172.17.0.2/32 -d 172.17.0.2/32 -p tcp -m tcp --dport 80 -j MASQUERADE
-A DOCKER ! -i docker0 -p tcp -m tcp --dport 8080 -j DNAT --to-destination 172.17.0.2:80
COMMIT
# Completed on Wed Apr  8 23:37:43 2015

---

码头工人信息

Containers: 1
Images: 25
Storage Driver: aufs
 Root Dir: /var/lib/docker/aufs
 Backing Filesystem: extfs
 Dirs: 27
Execution Driver: native-0.2
Kernel Version: 3.16.0-4-amd64
Operating System: Debian GNU/Linux 8 (jessie)
CPUs: 4
Total Memory: 7.746 GiB
Name: nuc-001
ID: WCMU:MN3T:VFKR:IU42:6423:OEI6:IB5Q:WBNV:K75H:JZDS:UWU5:57WD
WARNING: No memory limit support
WARNING: No swap limit support

Answer 1

Docker 在内部使用 iptables 将连接到 docker 主机的 8080 端口转发到容器上侦听端口 80 的服务。您配置中的关键是这一行 -

-A DOCKER ! -i docker0 -p tcp -m tcp --dport 8080 -j DNAT --to-destination 172.17.0.2:80

通过插入 ( -I) 新的转发行，您可以阻止将连接转发到容器 IP，在本例中为 172.17.0.2。试试这个规则——

/sbin/iptables -I FORWARD '!' -s 123.456.789.0 -d 172.17.0.2 -p tcp --dport 80 -j DROP

Answer 2

您可以将端口绑定到本地计算机。然后docker不会将端口暴露给外部。(iptables)

docker run -p 127.0.0.1:8080:8080 some_image