README.md auf Englisch gekürtzt

cannot build the image automatically

This reverts commit fc7840efef.

.dockerignore

@@ -1,3 +1,5 @@
 *
+!LICENSE
+!README.md
 !ufw-docker
 !docker-entrypoint.sh

.drone.yml

@@ -0,0 +1,15 @@
+---
+kind: pipeline
+type: docker
+name: default
+
+steps:
+- name: Fetch Submodules
+  image: alpine/git
+  commands:
+  - git submodule update --init --recursive --depth=1 --remote
+
+- name: Testing
+  image: ubuntu:bionic
+  commands:
+  - ./test.sh

.github/workflows/testing.yml

@@ -0,0 +1,16 @@
+name: Unit Testing ufw-docker
+on: [push, pull_request]
+jobs:
+  test:
+    name: Unit Testing
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Checkout submodules
+      shell: bash
+      run: |
+        auth_header="$(git config --local --get http.https://github.com/.extraheader)"
+        git submodule sync --recursive
+        git -c "http.extraheader=$auth_header" -c protocol.version=2 submodule update --init --force --recursive --depth=1
+    - name: Test ufw-docker
+      run: ./test.sh

.gitignore

@@ -0,0 +1 @@
+.vagrant

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "test/bach"]
+	path = test/bach
+	url = https://github.com/bach-sh/bach.git

.travis.yml

@@ -0,0 +1,8 @@
+language: bash
+os: linux
+dist: trusty
+script:
+- bash test.sh
+notifications:
+  slack:
+    secure: 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

Dockerfile

@@ -1,13 +1,19 @@
-FROM ubuntu:18.04
+FROM ubuntu:24.04
 
+ARG docker_version="27.3.1"
+
+ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update \
-    && apt-get install -y --no-install-recommends apt-transport-https \
-               ca-certificates curl software-properties-common gnupg dirmngr \
-    && apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 9DC858229FC7DD38854AE2D88D81803C0EBFCD88 \
-    && add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
-                          $(lsb_release -cs) stable" \
+    && apt-get install -y ca-certificates curl gnupg lsb-release \
+    && mkdir -p /etc/apt/keyrings \
+    && curl -fsSL https://download.docker.com/linux/ubuntu/gpg | gpg --dearmor -o /etc/apt/keyrings/docker.gpg \
+    && echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg]" \
+            "https://download.docker.com/linux/ubuntu" "$(lsb_release -cs) stable" \
+            | tee /etc/apt/sources.list.d/docker.list > /dev/null \
     && apt-get update \
-    && apt-get install -y --no-install-recommends ufw "docker-ce=18.06.1~*" \
+    && apt-get install -y --no-install-recommends locales ufw \
+    && apt-get install -y --no-install-recommends "docker-ce=$(apt-cache madison docker-ce | grep -m1 -F "${docker_version}" | cut -d'|' -f2 | tr -d '[[:blank:]]')" \
+    && locale-gen en_US.UTF-8 \
     && apt-get clean autoclean \
     && apt-get autoremove --yes \
     && rm -rf /var/lib/{apt,dpkg,cache,log}/
@@ -17,3 +23,5 @@ ADD ufw-docker docker-entrypoint.sh /usr/bin/
 ENTRYPOINT ["/usr/bin/docker-entrypoint.sh"]
 
 CMD ["start"]
+
+ADD LICENSE README.md /

README.md

@@ -1,8 +1,10 @@
 To Fix The Docker and UFW Security Flaw Without Disabling Iptables
 ==================
 
+[![Build Status](https://travis-ci.org/chaifeng/ufw-docker.svg)](https://travis-ci.org/chaifeng/ufw-docker)
+[![chaifeng/ufw-docker-agent](https://img.shields.io/docker/pulls/chaifeng/ufw-docker-agent)](https://hub.docker.com/r/chaifeng/ufw-docker-agent)
+
 - [English](#tldr)
-- [中文](#太长不想读)
 
 ## TL;DR
 
@@ -67,25 +69,32 @@ Modify the UFW configuration file `/etc/ufw/after.rules` and add the following r
     # BEGIN UFW AND DOCKER
     *filter
     :ufw-user-forward - [0:0]
+    :ufw-docker-logging-deny - [0:0]
     :DOCKER-USER - [0:0]
+    -A DOCKER-USER -j ufw-user-forward
+
     -A DOCKER-USER -j RETURN -s 10.0.0.0/8
     -A DOCKER-USER -j RETURN -s 172.16.0.0/12
     -A DOCKER-USER -j RETURN -s 192.168.0.0/16
 
-    -A DOCKER-USER -j ufw-user-forward
+    -A DOCKER-USER -p udp -m udp --sport 53 --dport 1024:65535 -j RETURN
 
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 192.168.0.0/16
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 10.0.0.0/8
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 172.16.0.0/12
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 192.168.0.0/16
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 10.0.0.0/8
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 172.16.0.0/12
+    -A DOCKER-USER -j ufw-docker-logging-deny -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 192.168.0.0/16
+    -A DOCKER-USER -j ufw-docker-logging-deny -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 10.0.0.0/8
+    -A DOCKER-USER -j ufw-docker-logging-deny -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 172.16.0.0/12
+    -A DOCKER-USER -j ufw-docker-logging-deny -p udp -m udp --dport 0:32767 -d 192.168.0.0/16
+    -A DOCKER-USER -j ufw-docker-logging-deny -p udp -m udp --dport 0:32767 -d 10.0.0.0/8
+    -A DOCKER-USER -j ufw-docker-logging-deny -p udp -m udp --dport 0:32767 -d 172.16.0.0/12
 
     -A DOCKER-USER -j RETURN
+
+    -A ufw-docker-logging-deny -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW DOCKER BLOCK] "
+    -A ufw-docker-logging-deny -j DROP
+
     COMMIT
     # END UFW AND DOCKER
 
-Using command `sudo systemctl restart ufw** to restart UFW after changing the file. Now the public network can't access any published docker ports, the container and the private network can visit each other normally, and the containers can also access the external network from inside. **There may be some unknown reasons cause the UFW rules will not take effect after restart UFW, please reboot servers. **
+Using command `sudo systemctl restart ufw` or `sudo ufw reload` to restart UFW after changing the file. Now the public network can't access any published docker ports, the container and the private network can visit each other normally, and the containers can also access the external network from inside. **There may be some unknown reasons cause the UFW rules will not take effect after restart UFW, please reboot servers.**
 
 If you want to allow public networks to access the services provided by the Docker container, for example, the service port of a container is `80`. Run the following command to allow the public networks to access this service:
 
@@ -119,6 +128,10 @@ The following rules allow UFW to manage whether the public networks are allowed
 
     -A DOCKER-USER -j ufw-user-forward
 
+For example, we want to block all outgoing connections from inside a container whose IP address is 172.17.0.9 which means to block this container to access internet or external networks. Using the following command:
+
+    ufw route deny from 172.17.0.9 to any
+
 The following rules block connection requests initiated by all public networks, but allow internal networks to access external networks. For TCP protocol, it prevents from actively establishing a TCP connection from public networks. For UDP protocol, all accesses to ports which is less then 32767 are blocked. Why is this port? Since the UDP protocol is stateless, it is not possible to block the handshake signal that initiates the connection request as TCP does. For GNU/Linux we can find the local port range in the file `/proc/sys/net/ipv4/ip_local_port_range`. The default range is `32768 60999`. When accessing a UDP protocol service from a running container, the local port will be randomly selected one from the port range, and the server will return the data to this random port. Therefore, we can assume that the listening port of the UDP protocol inside all containers are less then `32768`. This is the reason that we don't want public networks to access the UDP ports that less then `32768`.
 
     -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 192.168.0.0/16
@@ -130,6 +143,12 @@ The following rules block connection requests initiated by all public networks,
 
     -A DOCKER-USER -j RETURN
 
+If a docker container doesn't follow the OS's settings when receiving data, that is to say, the minimal port number less than `32768`. For example, we have a Dnsmasq container. The minimal port number that Dnsmasq uses for receiving data is `1024`. We can use the following command to allow a bigger port range used for receiving DNS packages.
+
+    ufw route allow proto udp from any port 53 to any port 1024:65535
+
+Because DNS is a very common service, so there is already a firewall rule to allow a bigger port range to receive DNS packages.
+
 ## The reason for choosing `ufw-user-forward`, not `ufw-user-input`
 
 ### using `ufw-user-input`
@@ -190,7 +209,7 @@ Download `ufw-docker` script
 
     sudo wget -O /usr/local/bin/ufw-docker \
       https://github.com/chaifeng/ufw-docker/raw/master/ufw-docker
-    chmod +x /usr/local/bin/ufw-docker
+    sudo chmod +x /usr/local/bin/ufw-docker
 
 Then using the following command to modify the `after.rules` file of `ufw`
 
@@ -204,8 +223,8 @@ This command does the following things:
 
 We can only use this script on manager nodes to manage firewall rules when using in Swarm mode.
 
-- Modify all `after.rules` files on all nodes, including managers and workers
-- Deploy this script on mananger nodes
+- Modifying all `after.rules` files on all nodes, including managers and workers
+- Deploying this script on manager nodes
 
 Running in Docker Swarm mode, this script will add a global service `ufw-docker-agent`. The image [chaifeng/ufw-docker-agent](https://hub.docker.com/r/chaifeng/ufw-docker-agent/) is also automatically built from this project.
 
@@ -215,6 +234,14 @@ Show help
 
     ufw-docker help
 
+Check the installation of firewall rules in UFW configurations
+
+    ufw-docker check
+
+Update UFW configurations, add the necessary firewall rules
+
+    ufw-docker install
+
 Show the current firewall allowed forward rules
 
     ufw-docker status
@@ -231,6 +258,10 @@ Expose the `443` port of the container `httpd` and the protocol is `tcp`
 
     ufw-docker allow httpd 443/tcp
 
+Expose the `443` port of the container `httpd` and the protocol is `tcp` and the network is `foobar-external-network` when the container `httpd` is attached to multiple networks
+
+    ufw-docker allow httpd 443/tcp foobar-external-network
+
 Expose all published ports of the container `httpd`
 
     ufw-docker allow httpd
@@ -255,258 +286,35 @@ Remove rules from all nodes related to the service `web`
 
     ufw-docker service delete allow web
 
-## Discussions
+### Try it out
 
-- [What is the best practice of docker + ufw under Ubuntu - Stack Overflow](https://stackoverflow.com/questions/30383845/what-is-the-best-practice-of-docker-ufw-under-ubuntu/51741599#comment91451547_51741599)
-- [docker and ufw serious problems · Issue #4737 · moby/moby](https://github.com/moby/moby/issues/4737#issuecomment-420112149)
+We use [Vagrant](https://www.vagrantup.com/) to set up a local testing environment. 
 
+Run the following command to create 1 master node and 2 worker nodes
 
-## 太长不想读
+    vagrant up
 
-请直接看[解决 UFW 和 Docker 的问题](#解决-ufw-和-docker-的问题)。
+Log into the master node
 
-## 问题
+    vagrant ssh master
 
-UFW 是 Ubuntu 上很流行的一个 iptables 前端，可以非常方便的管理防火墙的规则。但是当安装了 Docker，UFW 无法管理 Docker 发布出来的端口了。
-
-具体现象是：
-
-1. 在一个对外提供服务的服务器上启用了 UFW，并且默认阻止所有未被允许的传入连接。
-2. 运行了一个 Docker 容器，并且使用 `-p` 选项来把该容器的某个端口发布到服务器的所有 IP 地址上。比如：`docker run -d --name httpd -p 0.0.0.0:8080:80 httpd:alpine` 将会运行一个 httpd 服务，并且将容器的 `80` 端口发布到服务器的 `8080` 端口上。
-3. UFW 将不会阻止所有对 `8080` 端口访问的请求，用命令 `ufw deny 8080` 也无法阻止外部访问这个端口。
-
-这个问题其实挺严重的，这意味着本来只是为了在内部提供服务的一个端口被暴露在公共网络上。
-
-在网络上搜索 "ufw docker" 可以发现很多的讨论：
-
-- https://github.com/moby/moby/issues/4737
-- https://forums.docker.com/t/running-multiple-docker-containers-with-ufw-and-iptables-false/8953
-- https://www.techrepublic.com/article/how-to-fix-the-docker-and-ufw-security-flaw/
-- https://blog.viktorpetersson.com/2014/11/03/the-dangers-of-ufw-docker.html
-- https://askubuntu.com/questions/652556/uncomplicated-firewall-ufw-is-not-blocking-anything-when-using-docker
-- https://chjdev.com/2016/06/08/docker-ufw/
-- https://askubuntu.com/questions/652556/uncomplicated-firewall-ufw-is-not-blocking-anything-when-using-docker
-- https://my.oschina.net/abcfy2/blog/539485
-- https://www.v2ex.com/amp/t/466666
-- https://blog.36web.rocks/2016/07/08/docker-behind-ufw.html
-- ...
-
-基本上可以找到的解决办法就是首先禁用 docker 的 iptables 功能，但这也意味着放弃了 docker 的网络管理功能，很典型的现象就是容器将无法访问外部网络。在有的文章中也提到了可以在 UFW 的配置文件中手工添加一条规则，比如 `-A POSTROUTING ! -o docker0 -s 172.17.0.0/16 -j MASQUERADE`。但这也只是允许了 `172.17.0.0/16` 这个网络。如果有了新增的网络，我们也必须手工再为新增的网络添加这样类似的 iptables 规则。
-
-## 期望的目标
-
-目前网络上的解决方案都非常类似，而且也不优雅，我希望一个新的解决方案可以：
-
-1. 不要禁用 Docker 的 iptables，像往常一样由 Docker 来管理自己的网络。这样有任何新增的 Docker 网络时都无需手工维护 iptables 规则，也避免了在 Docker 中禁用 iptables 之后可能带来的副作用。
-2. 公共网络不可以访问 Docker 发布出来的端口，即使是使用类似 `-p 0.0.0.0:8080:80` 的选项把端口发布在所有的 IP 地址上。容器之间、内部网络之间都可以正常互相访问，只有公共网络不可以访问。
-   虽然可以让 Docker 把容器的某一个端口映射到服务器的私有 IP 地址上，这样公共网络上将不会访问到这个端口。但是这个服务器可能有多个私有 IP 地址，这些私有 IP 地址可能也会发生变化。
-3. 可以很方便的允许公共网络直接访问某个容器的端口，而无需额外的软件和配置。就像是用 `ufw allow 8080` 这样允许外部访问 8080 端口，然后用 `ufw delete allow 8080` 就不再允许外部访问。
-
-## 如何做？
-
-### 撤销原先的修改
-
-如果已经按照目前网络上搜索到解决方案修改过了，请先修改回来，包括：
-
-1. 启用 Docker 的 iptables 功能，删除所有类似 `--iptables=false` 的修改，包括 `/etc/docker/daemon.json` 配置文件。
-2. UFW 的默认 `FORWARD` 规则改回默认的 `DROP`，而非 `ACCEPT`。
-3. 删除 UFW 配置文件 `/etc/ufw/after.rules` 中与 Docker 网络相关的规则。
-4. 如果修改了 Docker 相关的配置文件，重启 Docker。稍后还要修改 UFW 的配置，可以一并重启。
-
-### 解决 UFW 和 Docker 的问题
-
-目前新的解决方案只需要修改一个 UFW 配置文件即可，Docker 的所有配置和选项都保持默认。
-
-修改 UFW 的配置文件 `/etc/ufw/after.rules`，在最后添加上如下规则：
-
-    # BEGIN UFW AND DOCKER
-    *filter
-    :ufw-user-forward - [0:0]
-    :DOCKER-USER - [0:0]
-    -A DOCKER-USER -j RETURN -s 10.0.0.0/8
-    -A DOCKER-USER -j RETURN -s 172.16.0.0/12
-    -A DOCKER-USER -j RETURN -s 192.168.0.0/16
-
-    -A DOCKER-USER -j ufw-user-forward
-
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 192.168.0.0/16
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 10.0.0.0/8
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 172.16.0.0/12
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 192.168.0.0/16
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 10.0.0.0/8
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 172.16.0.0/12
-
-    -A DOCKER-USER -j RETURN
-    COMMIT
-    # END UFW AND DOCKER
- 
-然后重启 UFW，`sudo systemctl restart ufw`。现在外部就已经无法访问 Docker 发布出来的任何端口了，但是容器内部以及私有网络地址上可以正常互相访问，而且容器也可以正常访问外部的网络。**可能由于某些未知原因，重启 UFW 之后规则也无法生效，请重启服务器。**
-
-如果希望允许外部网络访问 Docker 容器提供的服务，比如有一个容器的服务端口是 `80`。那就可以用以下命令来允许外部网络访问这个服务：
-
-    ufw route allow proto tcp from any to any port 80
-
-这个命令会允许外部网络访问所有用 Docker 发布出来的并且内部服务端口为 `80` 的所有服务。
-
-请注意，这个端口 `80` 是容器的端口，而非使用 `-p 0.0.0.0:8080:80` 选项发布在服务器上的 `8080` 端口。
-
-如果有多个容器的服务端口为 80，但只希望外部网络访问某个特定的容器。比如该容器的私有地址为 `172.17.0.2`，就用类似下面的命令：
-
-    ufw route allow proto tcp from any to 172.17.0.2 port 80
-
-如果一个容器的服务是 UDP 协议，假如是 DNS 服务，可以用下面的命令来允许外部网络访问所有发布出来的 DNS 服务：
-
-    ufw route allow proto udp from any to any port 53
-
-同样的，如果只针对一个特定的容器，比如 IP 地址为 `172.17.0.2`：
-
-    ufw route allow proto udp from any to 172.17.0.2 port 53
-
-### 解释
-
-在新增的这段规则中，下面这段规则是为了让私有网络地址可以互相访问。通常情况下，私有网络是比公共网络更信任的。
-
-    -A DOCKER-USER -j RETURN -s 10.0.0.0/8
-    -A DOCKER-USER -j RETURN -s 172.16.0.0/12
-    -A DOCKER-USER -j RETURN -s 192.168.0.0/16
-
-下面的规则是为了可以用 UFW 来管理外部网络是否允许访问 Docker 容器提供的服务，这样我们就可以在一个地方来管理防火墙的规则了。
-
-    -A DOCKER-USER -j ufw-user-forward
-
-下面的规则阻止了所有外部网络发起的连接请求，但是允许内部网络访问外部网络。对于 TCP 协议，是阻止了从外部网络主动建立 TCP 连接。对于 UDP，是阻止了所有小余端口 `32767` 的访问。为什么是这个端口的？由于 UDP 协议是无状态的，无法像 TCP 那样阻止发起建立连接请求的握手信号。在 GNU/Linux 上查看文件 `/proc/sys/net/ipv4/ip_local_port_range` 可以看到发出 TCP/UDP 数据后，本地源端口的范围，默认为 `32768 60999`。当从一个运行的容器对外访问一个 UDP 协议的服务时，本地端口将会从这个端口范围里面随机选择一个，服务器将会把数据返回到这个随机端口上。所以，我们可以假定所有容器内部的 UDP 协议的监听端口都小余 `32768`，不允许外部网络主动连接小余 `32768` 的 UDP 端口。
-
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 192.168.0.0/16
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 10.0.0.0/8
-    -A DOCKER-USER -j DROP -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 172.16.0.0/12
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 192.168.0.0/16
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 10.0.0.0/8
-    -A DOCKER-USER -j DROP -p udp -m udp --dport 0:32767 -d 172.16.0.0/12
-
-    -A DOCKER-USER -j RETURN
-
-### 选择 `ufw-user-forward` 而不是 `ufw-user-input` 的原因
-
-#### 使用 `ufw-user-input`
-
-优点：
-
-使用的 UFW 命令比较简单，也比较容易理解，而且也支持老版本的 Ubuntu
-
-比如，允许公众网络访问一个已经发布出来的容器端口 `8080`，使用命令：
-
-    ufw allow 8080
-
-缺点：
-
-不仅仅是暴露了已经发布的容器端口，也暴露了主机上的端口。
-
-比如，如果在主机上运行了一个端口为 `8080` 的服务。命令 `ufw allow 8080` 允许了公共网络访问这个服务，也允许了访问所有已经发布的容器端口为 `8080` 的服务。但是我们可能只是希望保留主机上的这个服务，或者是运行在容器里面的服务，而不是两个同时暴露。
-
-为了避免这个问题，我们可能需要使用类似下面的命令来管理已经发布的容器端口：
-
-    ufw allow proto tcp from any to 172.16.0.3 port 8080
-
-#### 使用 `ufw-user-forward`
-
-优点：
-
-不会因为同一条命令而同时暴露主机和容器里面的服务。
-
-比如，如果我们希望暴露所有容器端口为 `8080` 的服务，使用下面的命令：
-
-    ufw route allow 8080
-
-现在公共网络可以访问所有容器端口为 `8080` 的已经发布的服务，但是运行在主机上的 `8080` 服务仍然不会被公开。如果我们希望公开主机上的 `8080` 端口，可以执行下面的命令：
-
-    ufw allow 8080
-
-缺点：
-
-不支持老版本的 Ubuntu，而且命令的使用上可能也会比较复杂。
-
-#### 结论
-
-如果我们正在使用老版本的 Ubuntu，我们可以使用 `ufw-user-input`。但是要小心避免把不该暴露的服务暴露出去。
-
-如果正在使用支持 `ufw route` 命令的新版本的 Ubuntu，我们最好使用 `ufw-user-forward`，并且使用 `ufw route` 来管理与容器相关的防火墙规则。
-
-## `ufw-docker` 工具
-
-现在这个脚本也支持 Docker Swarm。
-
-### 安装
-
-下载 `ufw-docker` 脚本
-
-    sudo wget -O /usr/local/bin/ufw-docker \
-      https://github.com/chaifeng/ufw-docker/raw/master/ufw-docker
-    chmod +x /usr/local/bin/ufw-docker
-
-使用下列命令来修改 ufw 的 `after.rules` 文件
-
-    ufw-docker install
-
-这个命令做了以下事情：
-- 备份文件 `/etc/ufw/after.rules`
-- 把 UFW 和 Docker 的相关规则添加到文件 `after.rules` 的末尾
-
-#### 为 Docker Swarm 环境安装
-
-仅仅可以在管理节点上使用 `ufw-docker` 这个脚本来管理防火墙规则。
-
-- 在所有的节点上修改 `after.rules` 这个文件，包括管理节点和工作节点
-- 在管理节点上部署这个脚本
-
-运行在 Docker Swarm 模式下，这个脚本将会创建一个全局服务 `ufw-docker-agent`。这个镜像 [chaifeng/ufw-docker-agent](https://hub.docker.com/r/chaifeng/ufw-docker-agent/) 是由本项目自动构建的。
-
-### 使用方法
-
-显示帮助
-
-    ufw-docker help
-
-显示当前防火墙允许的转发规则
-
-    ufw-docker status
-
-列出所有和容器 `httpd` 相关的防火墙规则
-
-    ufw-docker list httpd
-
-暴露容器 `httpd` 的 `80` 端口
-
-    ufw-docker allow httpd 80
-
-暴露容器 `httpd` 的 `443` 端口，且协议为 `tcp`
-
-    ufw-docker allow httpd 443/tcp
-
-把容器 `httpd` 的所有映射端口都暴露出来
-
-    ufw-docker allow httpd
-
-删除所有和容器 `httpd` 相关的防火墙规则
-
-    ufw-docker delete allow httpd
-
-删除容器 `httpd` 的 `tcp` 端口 `443` 的规则
-
-    ufw-docker delete allow httpd 443/tcp
-
-暴露服务 `web` 的 `80` 端口
+After logging in, create a `web` service
 
     docker service create --name web --publish 8080:80 httpd:alpine
 
-    ufw-docker service allow web 80
-    # 或者
-    ufw-docker service allow web 80/tcp
+We shouldn't visit this `web` service from our host
 
-删除与服务 `web` 相关的规则
+    curl -v http://192.168.56.131:8080
 
-    ufw-docker service delete allow web
+On the master node, run the command to allow the public access port `80` of the `web` service.
 
-## 讨论
+    sudo ufw-docker service allow web 80
+
+We can access the `web` service from our host now
+
+    curl "http://192.168.56.13{0,1,2}:8080"
+
+## Discussions
 
 - [What is the best practice of docker + ufw under Ubuntu - Stack Overflow](https://stackoverflow.com/questions/30383845/what-is-the-best-practice-of-docker-ufw-under-ubuntu/51741599#comment91451547_51741599)
-- [docker and ufw serious problems · Issue #4737 · moby/moby](https://github.com/moby/moby/issues/4737#issuecomment-420112149)
+- [docker and ufw serious problems · Issue #4737 · moby/moby](https://github.com/moby/moby/issues/4737#issuecomment-420112149)

Vagrantfile

@@ -0,0 +1,242 @@
+# frozen_string_literal: true
+
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+ENV['VAGRANT_NO_PARALLEL']="true"
+
+Vagrant.configure('2') do |config|
+  ubuntu_version = File.readlines("Dockerfile").filter { |line|
+    line.start_with?("FROM ")
+  }.first.match(/\d\d\.\d\d/)[0]
+
+  docker_version = File.readlines("Dockerfile").filter { |line|
+    line.start_with?("ARG docker_version=")
+  }.first.match(/"([\d\.]+)"/)[1]
+
+  config.vm.box = "chaifeng/ubuntu-#{ubuntu_version}-docker-#{docker_version}"
+
+  config.vm.provider 'virtualbox' do |vb|
+    vb.memory = '1024'
+    vb.default_nic_type = "virtio"
+  end
+
+  config.vm.provider 'parallels' do |prl|
+    prl.memory = '1024'
+    prl.check_guest_tools = false
+  end
+
+  ip_prefix="192.168.56"
+
+  config.vm.provision 'docker-daemon-config', type: 'shell', inline: <<-SHELL
+    set -eu
+    if [[ ! -f /etc/docker/daemon.json ]]; then
+      echo '{' >> /etc/docker/daemon.json
+      echo '  "insecure-registries": ["localhost:5000", "#{ip_prefix}.130:5000"]' >> /etc/docker/daemon.json
+      [[ -n "#{ENV['DOCKER_REGISTRY_MIRROR']}" ]] &&
+        echo '  , "registry-mirrors": ["#{ENV['DOCKER_REGISTRY_MIRROR']}"]' >> /etc/docker/daemon.json
+      echo '}' >> /etc/docker/daemon.json
+      if type systemctl &>/dev/null; then
+        systemctl restart docker
+      else
+        service docker restart
+      fi
+    fi
+  SHELL
+
+  config.vm.provision 'ufw-docker', type: 'shell', inline: <<-SHELL
+    set -euo pipefail
+    export DEBUG=true
+    lsb_release -is | grep -Fi ubuntu
+    /vagrant/ufw-docker check || {
+      ufw allow OpenSSH
+      ufw allow from #{ip_prefix}.128/28 to any
+
+      yes | ufw enable || true
+      ufw status | grep '^Status: active'
+
+      /vagrant/ufw-docker install
+
+      sed -i -e 's,192\.168\.0\.0/16,#{ip_prefix}.128/28,' /etc/ufw/after.rules
+
+      systemctl restart ufw
+
+      [[ -L /usr/local/bin/ufw-docker ]] || ln -s /vagrant/ufw-docker /usr/local/bin/
+
+      iptables -I DOCKER-USER 4 -p udp -j LOG --log-prefix '[UFW DOCKER] '
+    }
+  SHELL
+
+  private_registry="#{ip_prefix}.130:5000"
+
+  config.vm.define "master" do |master|
+    master_ip_address = "#{ip_prefix}.130"
+    master.vm.hostname = "master"
+    master.vm.network "private_network", ip: "#{master_ip_address}"
+
+    master.vm.provision "unit-testing", preserve_order: true, type: 'shell', inline: <<-SHELL
+        set -euo pipefail
+        /vagrant/test.sh
+    SHELL
+
+    master.vm.provision "docker-registry", preserve_order: true, type: 'docker' do |d|
+      d.run "registry",
+            image: "registry:2",
+            args: "-p 5000:5000",
+            restart: "always",
+            daemonize: true
+    end
+
+    ufw_docker_agent_image = "#{private_registry}/chaifeng/ufw-docker-agent:test-legacy"
+
+    master.vm.provision "docker-build-ufw-docker-agent", preserve_order: true, type: 'shell', inline: <<-SHELL
+      set -euo pipefail
+      suffix="$(iptables --version | grep -o '\\(nf_tables\\|legacy\\)')"
+      docker build -t "#{ufw_docker_agent_image}-${suffix}" /vagrant
+      docker push "#{ufw_docker_agent_image}-${suffix}"
+
+      echo "export UFW_DOCKER_AGENT_IMAGE=#{ufw_docker_agent_image}-${suffix}" > /etc/profile.d/ufw-docker.sh
+      echo "export DEBUG=true" >> /etc/profile.d/ufw-docker.sh
+
+      echo "Defaults env_keep += UFW_DOCKER_AGENT_IMAGE" > /etc/sudoers.d/98_ufw-docker
+      echo "Defaults env_keep += DEBUG" >> /etc/sudoers.d/98_ufw-docker
+    SHELL
+
+    master.vm.provision "swarm-init", preserve_order: true, type: 'shell', inline: <<-SHELL
+      set -euo pipefail
+      docker info | fgrep 'Swarm: active' && exit 0
+
+      docker swarm init --advertise-addr "#{master_ip_address}"
+      docker swarm join-token worker --quiet > /vagrant/.vagrant/docker-join-token
+    SHELL
+
+    master.vm.provision "build-webapp", preserve_order: true, type: 'shell', inline: <<-SHELL
+        set -euo pipefail
+        docker build -t #{private_registry}/chaifeng/hostname-webapp - <<\\DOCKERFILE
+FROM httpd:alpine
+
+RUN { echo '#!/bin/sh'; \\
+    echo 'set -e; (echo -n "${name:-Hi} "; hostname;) > /usr/local/apache2/htdocs/index.html'; \\
+    echo 'grep "^Listen 7000" || echo Listen 7000 >> /usr/local/apache2/conf/httpd.conf'; \\
+    echo 'grep "^Listen 8080" || echo Listen 8080 >> /usr/local/apache2/conf/httpd.conf'; \\
+    echo 'exec "$@"'; \\
+    } > /entrypoint.sh; chmod +x /entrypoint.sh
+
+ENTRYPOINT ["/entrypoint.sh"]
+CMD ["httpd-foreground"]
+DOCKERFILE
+        docker push #{private_registry}/chaifeng/hostname-webapp
+    SHELL
+
+    master.vm.provision "local-webapp", preserve_order: true, type: 'shell', inline: <<-SHELL
+        set -euo pipefail
+        for name in public:18080 local:8000; do
+            webapp="${name%:*}_webapp"
+            port="${name#*:}"
+            if docker inspect "$webapp" &>/dev/null; then docker rm -f "$webapp"; fi
+            docker run -d --restart unless-stopped --name "$webapp" \
+                -p "$port:80" --env name="$webapp" #{private_registry}/chaifeng/hostname-webapp
+            sleep 1
+        done
+
+        ufw-docker allow public_webapp
+    SHELL
+
+    master.vm.provision "multiple-network", preserve_order: true, type: 'shell', inline: <<-SHELL
+      set -euo pipefail
+      if ! docker network ls | grep -F foo-internal; then
+          docker network create --internal foo-internal
+      fi
+      if ! docker network ls | grep -F bar-external; then
+          docker network create bar-external
+      fi
+
+      for app in internal-multinet-app:7000 public-multinet-app:17070; do
+          if ! docker inspect "${app%:*}" &>/dev/null; then
+              docker run -d --restart unless-stopped --name "${app%:*}" \
+                         -p "${app#*:}":80 --env name="${app}" \
+                         --network foo-internal \
+                         192.168.56.130:5000/chaifeng/hostname-webapp
+              docker network connect bar-external "${app%:*}"
+          fi
+      done
+
+      ufw-docker allow public-multinet-app 80 bar-external
+      ufw-docker allow internal-multinet-app 80 foo-internal
+    SHELL
+
+    master.vm.provision "swarm-webapp", preserve_order: true, type: 'shell', inline: <<-SHELL
+      set -euo pipefail
+        for name in public:29090 local:9000; do
+            webapp="${name%:*}_service"
+            port="${name#*:}"
+            if docker service inspect "$webapp" &>/dev/null; then docker service rm "$webapp"; fi
+            docker service create --name "$webapp" \
+                --publish "${port}:80" --env name="$webapp" --replicas 3 #{private_registry}/chaifeng/hostname-webapp
+        done
+
+        ufw-docker service allow public_service 80/tcp
+
+        docker service inspect "public_multiport" ||
+            docker service create --name "public_multiport" \
+                --publish "40080:80" --publish "47000:7000" --publish "48080:8080" \
+                --env name="public_multiport" --replicas 3 #{private_registry}/chaifeng/hostname-webapp
+
+        ufw-docker service allow public_multiport 80/tcp
+        ufw-docker service allow public_multiport 8080/tcp
+    SHELL
+  end
+
+  1.upto 2 do |ip|
+    config.vm.define "node#{ip}" do | node |
+      node.vm.hostname = "node#{ip}"
+      node.vm.network "private_network", ip: "#{ip_prefix}.#{ 130 + ip }"
+
+      node.vm.provision "swarm-join", preserve_order: true, type: 'shell', inline: <<-SHELL
+        set -euo pipefail
+        docker info | fgrep 'Swarm: active' && exit 0
+
+        [[ -f /vagrant/.vagrant/docker-join-token ]] &&
+        docker swarm join --token "$(</vagrant/.vagrant/docker-join-token)" #{ip_prefix}.130:2377
+      SHELL
+    end
+  end
+
+  config.vm.define "node-internal" do |node|
+    node.vm.hostname = "node-internal"
+    node.vm.network "private_network", ip: "#{ip_prefix}.142"
+  end
+
+  config.vm.define "external" do |external|
+    external.vm.hostname = "external"
+    external.vm.network "private_network", ip: "#{ip_prefix}.127"
+
+    external.vm.provision "testing", preserve_order: true, type: 'shell', inline: <<-SHELL
+        set -euo pipefail
+        set -x
+        server="http://#{ip_prefix}.130"
+        function test-webapp() {
+          if timeout 3 curl --silent "$@"
+          then echo "Success: $*"
+          else echo "Cannot visit: $*"; return 1
+          fi
+        }
+        test-webapp "$server:18080"
+        ! test-webapp "$server:8000"
+
+        test-webapp "$server:17070" # multiple networks app
+        ! test-webapp "$server:7000" # internal multiple networks app
+
+        test-webapp "$server:29090"
+        ! test-webapp "$server:9000"
+
+        test-webapp "$server:40080"
+        test-webapp "$server:48080"
+        ! test-webapp "$server:47000"
+
+        echo "====================="
+        echo "      TEST DONE      "
+        echo "====================="
+    SHELL
+  end
+end

test.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+set -uo pipefail
+
+function out() {
+    printf "\n\e[1;37;497;m%s\e[0;m\n" "$@"
+} >&2
+
+function err() {
+    printf "\n\e[1;37;41;m%s\e[0;m\n\n" "$@"
+} >&2
+
+retval=0
+cd "$(dirname "${BASH_SOURCE}")"
+for file in test/*.test.sh; do
+    out "Running $file"
+    if grep -E "^[[:blank:]]*BACH_TESTS=.+" "$file"; then
+        err "Found defination of BACH_TESTS in $file"
+        retval=1
+    fi
+    bash "$file" || retval=1
+done
+
+if [[ "$retval" -ne 0 ]]; then
+    err "Test failed!"
+fi
+
+exit "$retval"

test/ufw-docker-service.test.sh

@@ -0,0 +1,289 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+working_dir="$(cd "$(dirname "$BASH_SOURCE")"; pwd -P)"
+source "$working_dir"/bach/bach.sh
+
+@setup {
+    set -euo pipefail
+
+    ufw_docker_agent=ufw-docker-agent
+    ufw_docker_agent_image=chaifeng/ufw-docker-agent:181005
+}
+
+@setup-test {
+    @mocktrue ufw status
+    @mocktrue grep -Fq "Status: active"
+
+    @ignore remove_blank_lines
+    @ignore echo
+    @ignore err
+
+    DEFAULT_PROTO=tcp
+    GREP_REGEXP_INSTANCE_NAME="[-_.[:alnum:]]\\+"
+    DEBUG=false
+}
+
+function die() {
+    return 1
+}
+
+function load-ufw-docker-function() {
+    set -euo pipefail
+
+    @load_function "$working_dir/../ufw-docker" "$1"
+}
+
+
+test-ufw-docker--service-not-parameters() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service
+}
+test-ufw-docker--service-not-parameters-assert() {
+    ufw-docker--help
+}
+
+
+test-ufw-docker--service-allow() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service allow
+}
+test-ufw-docker--service-allow-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-allow-webapp() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service allow webapp
+}
+test-ufw-docker--service-allow-webapp-assert() {
+    #ufw-docker--service-allow webapp "" ""
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-allow-webapp-80tcp() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service allow webapp 80/tcp
+}
+test-ufw-docker--service-allow-webapp-80tcp-assert() {
+    ufw-docker--service-allow webapp 80/tcp
+}
+
+
+test-ufw-docker--service-delete-deny() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service delete deny
+}
+test-ufw-docker--service-delete-deny-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-delete-allow-no-service() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service delete allow
+}
+test-ufw-docker--service-delete-allow-no-service-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-delete-allow-webapp() {
+    load-ufw-docker-function ufw-docker--service
+
+    ufw-docker--service delete allow webapp
+}
+test-ufw-docker--service-delete-allow-webapp-assert() {
+    ufw-docker--service-delete webapp
+}
+
+
+test-ufw-docker--get-service-id() {
+    load-ufw-docker-function ufw-docker--get-service-id
+    ufw-docker--get-service-id database
+}
+test-ufw-docker--get-service-id-assert() {
+    docker service inspect database --format "{{.ID}}"
+}
+
+
+test-ufw-docker--get-service-name() {
+    load-ufw-docker-function ufw-docker--get-service-name
+    ufw-docker--get-service-name database
+}
+test-ufw-docker--get-service-name-assert() {
+    docker service inspect database --format "{{.Spec.Name}}"
+}
+
+
+test-ufw-docker--service-allow-invalid-port-syntax() {
+    @mockfalse grep -E '^[0-9]+(/(tcp|udp))?$'
+
+    load-ufw-docker-function ufw-docker--service-allow
+    ufw-docker--service-allow webapp invalid-port
+}
+test-ufw-docker--service-allow-invalid-port-syntax-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-allow-an-non-existed-service() {
+    @mocktrue grep -E '^[0-9]+(/(tcp|udp))?$'
+    @mock ufw-docker--get-service-id web404 === @stdout ""
+
+    load-ufw-docker-function ufw-docker--service-allow
+    ufw-docker--service-allow web404 80/tcp
+}
+test-ufw-docker--service-allow-an-non-existed-service-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-allow-a-service-without-ports-published() {
+    @mocktrue grep -E '^[0-9]+(/(tcp|udp))?$'
+    @mock ufw-docker--get-service-id private-web === @stdout abcd1234
+    @mock ufw-docker--get-service-name private-web === @stdout private-web
+    @mock docker service inspect private-web \
+          --format '{{range .Endpoint.Spec.Ports}}{{.PublishedPort}} {{.TargetPort}}/{{.Protocol}}{{"\n"}}{{end}}' === @stdout ""
+
+    load-ufw-docker-function ufw-docker--service-allow
+    ufw-docker--service-allow private-web 80/tcp
+}
+test-ufw-docker--service-allow-a-service-without-ports-published-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-allow-a-service-while-agent-not-running() {
+    @mocktrue grep -E '^[0-9]+(/(tcp|udp))?$'
+    @mock ufw-docker--get-service-id webapp === @stdout abcd1234
+    @mock ufw-docker--get-service-name webapp === @stdout webapp
+    @mock docker service inspect webapp \
+          --format '{{range .Endpoint.Spec.Ports}}{{.PublishedPort}} {{.TargetPort}}/{{.Protocol}}{{"\n"}}{{end}}' \
+          === @stdout "53 53/udp" "80 80/tcp" "8080 8080/tcp"
+    @mockfalse docker service inspect ufw-docker-agent
+
+    load-ufw-docker-function ufw-docker--service-allow
+    ufw-docker--service-allow webapp 80/tcp
+}
+test-ufw-docker--service-allow-a-service-while-agent-not-running-assert() {
+    docker service create --name ufw-docker-agent --mode global \
+           --mount type=bind,source=/var/run/docker.sock,target=/var/run/docker.sock \
+           --mount type=bind,source=/etc/ufw,target=/etc/ufw,readonly=true \
+           --env ufw_docker_agent_image="chaifeng/ufw-docker-agent:181005" \
+           --env DEBUG="false" \
+           --env "ufw_public_abcd1234=webapp/80/tcp" \
+           "chaifeng/ufw-docker-agent:181005"
+}
+
+
+test-ufw-docker--service-allow-a-service-add-new-env() {
+    @mocktrue grep -E '^[0-9]+(/(tcp|udp))?$'
+    @mock ufw-docker--get-service-id webapp === @stdout abcd1234
+    @mock ufw-docker--get-service-name webapp === @stdout webapp
+    @mock docker service inspect webapp \
+          --format '{{range .Endpoint.Spec.Ports}}{{.PublishedPort}} {{.TargetPort}}/{{.Protocol}}{{"\n"}}{{end}}' \
+          === @stdout "53 53/udp" "80 80/tcp" "8080 8080/tcp"
+    @mocktrue docker service inspect ufw-docker-agent
+    @mock ufw-docker--get-env-list === @stdout "abcd1234 webapp/80/tcp"
+
+    load-ufw-docker-function ufw-docker--service-allow
+    ufw-docker--service-allow webapp 80/tcp
+}
+test-ufw-docker--service-allow-a-service-add-new-env-assert() {
+    docker service update --update-parallelism=0 \
+           --env-add ufw_docker_agent_image="chaifeng/ufw-docker-agent:181005" \
+           --env-add DEBUG="false" \
+           --env-add "ufw_public_abcd1234=webapp/80/tcp" \
+           --image "chaifeng/ufw-docker-agent:181005" \
+           ufw-docker-agent
+}
+
+
+test-ufw-docker--service-allow-a-service-update-a-env() {
+    @mocktrue grep -E '^[0-9]+(/(tcp|udp))?$'
+    @mock ufw-docker--get-service-id webapp === @stdout abcd1234
+    @mock ufw-docker--get-service-name webapp === @stdout webapp
+    @mock docker service inspect webapp \
+          --format '{{range .Endpoint.Spec.Ports}}{{.PublishedPort}} {{.TargetPort}}/{{.Protocol}}{{"\n"}}{{end}}' \
+          === @stdout "53 53/udp" "80 80/tcp" "8080 8080/tcp"
+    @mocktrue docker service inspect ufw-docker-agent
+    @mock ufw-docker--get-env-list === @stdout "a_different_id webapp/80/tcp"
+
+    load-ufw-docker-function ufw-docker--service-allow
+    ufw-docker--service-allow webapp 80/tcp
+}
+test-ufw-docker--service-allow-a-service-update-a-env-assert() {
+    docker service update --update-parallelism=0 \
+           --env-add ufw_docker_agent_image="chaifeng/ufw-docker-agent:181005" \
+           --env-add DEBUG="false" \
+           --env-add "ufw_public_abcd1234=webapp/80/tcp" \
+           --env-rm "ufw_public_a_different_id" \
+           --image "chaifeng/ufw-docker-agent:181005" \
+           ufw-docker-agent
+}
+
+
+test-ufw-docker--get-env-list() {
+    @mock docker service inspect ufw-docker-agent \
+          --format '{{range $k,$v := .Spec.TaskTemplate.ContainerSpec.Env}}{{ $v }}{{"\n"}}{{end}}' \
+          === @stdout \
+              "ufw_docker_agent_image=192.168.56.130:5000/chaifeng/ufw-docker-agent:test" \
+              "DEBUG=true" \
+              "ufw_public_zv6esvmwnmmgnlauqn7m77jo4=webapp/9090/tcp" \
+              "OTHER_ENV=blabla"
+
+    @mock sed -e '/^ufw_public_/!d' \
+              -e 's/^ufw_public_//' \
+              -e 's/=/ /' === @real sed -e '/^ufw_public_/!d' \
+                                        -e 's/^ufw_public_//' \
+                                        -e 's/=/ /'
+
+    load-ufw-docker-function ufw-docker--get-env-list
+    ufw-docker--get-env-list
+}
+test-ufw-docker--get-env-list-assert() {
+    @stdout "zv6esvmwnmmgnlauqn7m77jo4 webapp/9090/tcp"
+}
+
+
+test-ufw-docker--service-delete-no-matches() {
+    @mock ufw-docker--get-env-list === @stdout "ffff111 foo/80/tcp" "eeee2222 bar/53/udp"
+
+    load-ufw-docker-function ufw-docker--service-delete
+    ufw-docker--service-delete webapp
+}
+test-ufw-docker--service-delete-no-matches-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--service-delete-matches() {
+    @mock ufw-docker--get-env-list === @stdout "ffff111 foo/80/tcp" "eeee2222 bar/53/udp" "abcd1234 webapp/5000/tcp"
+
+    load-ufw-docker-function ufw-docker--service-delete
+    ufw-docker--service-delete webapp
+}
+test-ufw-docker--service-delete-matches-assert() {
+    docker service update --update-parallelism=0 \
+           --env-add ufw_docker_agent_image="${ufw_docker_agent_image}" \
+           --env-add "ufw_public_abcd1234=webapp/deny" \
+           --image "${ufw_docker_agent_image}" \
+           "${ufw_docker_agent}"
+}

test/ufw-docker.test.sh

@@ -0,0 +1,581 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+working_dir="$(cd "$(dirname "$BASH_SOURCE")"; pwd -P)"
+source "$working_dir"/bach/bach.sh
+
+@setup {
+    set -euo pipefail
+}
+
+@setup-test {
+    @mocktrue ufw status
+    @mocktrue grep -Fq "Status: active"
+
+    @mock iptables --version
+    @mocktrue grep -F '(legacy)'
+
+    @mocktrue docker -v
+    @mock docker -v === @stdout Docker version 0.0.0, build dummy
+
+    @mockpipe remove_blank_lines
+    @ignore echo
+    @ignore err
+
+    DEFAULT_PROTO=tcp
+    GREP_REGEXP_INSTANCE_NAME="[-_.[:alnum:]]\\+"
+
+    UFW_DOCKER_AGENT_IMAGE=chaifeng/ufw-docker-agent:090502-legacy
+}
+
+function ufw-docker() {
+    @source <(@sed -n '/^# __main__$/,$p' "$working_dir/../ufw-docker") "$@"
+}
+
+function load-ufw-docker-function() {
+    set -euo pipefail
+
+    @load_function "$working_dir/../ufw-docker" "$1"
+}
+
+test-ufw-docker-init-legacy() {
+    @mocktrue grep -F '(legacy)'
+    @source <(@sed '/PATH=/d' "$working_dir/../ufw-docker") help
+}
+test-ufw-docker-init-legacy-assert() {
+    iptables --version
+    test -n chaifeng/ufw-docker-agent:090502-legacy
+    trap on-exit EXIT INT TERM QUIT ABRT ERR
+    @dryrun cat
+}
+
+
+test-ufw-docker-init-nf_tables() {
+    @mockfalse grep -F '(legacy)'
+    @source <(@sed '/PATH=/d' "$working_dir/../ufw-docker") help
+}
+test-ufw-docker-init-nf_tables-assert() {
+    iptables --version
+    test -n chaifeng/ufw-docker-agent:090502-nf_tables
+    trap on-exit EXIT INT TERM QUIT ABRT ERR
+    @dryrun cat
+}
+
+
+test-ufw-docker-init() {
+    UFW_DOCKER_AGENT_IMAGE=chaifeng/ufw-docker-agent:100917
+    @source <(@sed '/PATH=/d' "$working_dir/../ufw-docker") help
+}
+test-ufw-docker-init-assert() {
+    test -n chaifeng/ufw-docker-agent:100917
+    trap on-exit EXIT INT TERM QUIT ABRT ERR
+    @dryrun cat
+}
+
+
+test-ufw-docker-help() {
+    ufw-docker help
+}
+test-ufw-docker-help-assert() {
+    ufw-docker--help
+}
+
+
+test-ufw-docker-without-parameters() {
+    ufw-docker
+}
+test-ufw-docker-without-parameters-assert() {
+    test-ufw-docker-help-assert
+}
+
+
+test-ufw-is-disabled() {
+    @mockfalse grep -Fq "Status: active"
+    @mock iptables --version === @stdout 'iptables v1.8.4 (legacy)'
+
+    ufw-docker
+}
+test-ufw-is-disabled-assert() {
+    die "UFW is disabled or you are not root user, or mismatched iptables legacy/nf_tables, current iptables v1.8.4 (legacy)"
+    ufw-docker--help
+}
+
+
+test-docker-is-installed() {
+    @mockfalse docker -v
+
+    ufw-docker
+}
+test-docker-is-installed-assert() {
+    die "Docker executable not found."
+    ufw-docker--help
+}
+
+
+test-ufw-docker-status() {
+    ufw-docker status
+}
+test-ufw-docker-status-assert() {
+    ufw-docker--status
+}
+
+
+test-ufw-docker-install() {
+    ufw-docker install
+}
+test-ufw-docker-install-assert() {
+    ufw-docker--install
+}
+
+
+test-ufw-docker-check() {
+    ufw-docker check
+}
+test-ufw-docker-check-assert() {
+    ufw-docker--check
+}
+
+
+test-ufw-docker-service() {
+    ufw-docker service allow httpd
+}
+test-ufw-docker-service-assert() {
+    ufw-docker--service allow httpd
+}
+
+
+test-ufw-docker-raw-command() {
+    ufw-docker raw-command status
+}
+test-ufw-docker-raw-command-assert() {
+    ufw-docker--raw-command status
+}
+
+
+test-ufw-docker-add-service-rule() {
+    ufw-docker add-service-rule httpd 80/tcp
+}
+test-ufw-docker-add-service-rule-assert() {
+    ufw-docker--add-service-rule httpd 80/tcp
+}
+
+
+test-ASSERT-FAIL-ufw-docker-delete-must-have-parameters() {
+    ufw-docker delete
+}
+
+
+test-ASSERT-FAIL-ufw-docker-list-must-have-parameters() {
+    ufw-docker list
+}
+
+
+test-ASSERT-FAIL-ufw-docker-allow-must-have-parameters() {
+    ufw-docker allow
+}
+
+
+test-ASSERT-FAIL-ufw-docker-delete-httpd-but-it-doesnt-exist() {
+    @mockfalse ufw-docker--instance-name httpd
+    ufw-docker delete httpd
+}
+
+
+test-ASSERT-FAIL-ufw-docker-list-httpd-but-it-doesnt-exist() {
+    @mockfalse ufw-docker--instance-name httpd
+    ufw-docker list httpd
+}
+
+
+test-ASSERT-FAIL-ufw-docker-allow-httpd-but-it-doesnt-exist() {
+    @mockfalse ufw-docker--instance-name httpd
+    ufw-docker allow httpd
+}
+
+
+test-ufw-docker-list-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker list httpd
+}
+test-ufw-docker-list-httpd-assert() {
+    ufw-docker--list httpd-container-name "" tcp ""
+}
+
+
+test-ufw-docker-allow-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd
+}
+test-ufw-docker-allow-httpd-assert() {
+    ufw-docker--allow httpd-container-name "" tcp ""
+}
+
+
+test-ufw-docker-allow-httpd-80() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd 80
+}
+test-ufw-docker-allow-httpd-80-assert() {
+    ufw-docker--allow httpd-container-name 80 tcp ""
+}
+
+
+test-ufw-docker-allow-httpd-80tcp() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd 80/tcp
+}
+test-ufw-docker-allow-httpd-80tcp-assert() {
+    ufw-docker--allow httpd-container-name 80 tcp ""
+}
+
+
+test-ufw-docker-allow-httpd-80udp() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd 80/udp
+}
+test-ufw-docker-allow-httpd-80udp-assert() {
+    ufw-docker--allow httpd-container-name 80 udp ""
+}
+
+
+test-ASSERT-FAIL-ufw-docker-allow-httpd-INVALID-port() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    @mock die 'invalid port syntax: "invalid".' === exit 1
+
+    ufw-docker allow httpd invalid
+}
+
+
+test-ufw-docker-list-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker list httpd
+}
+test-ufw-docker-list-httpd-assert() {
+    ufw-docker--list httpd-container-name "" tcp ""
+}
+
+
+test-ufw-docker-delete-allow-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker delete allow httpd
+}
+test-ufw-docker-delete-allow-httpd-assert() {
+    ufw-docker--delete httpd-container-name "" tcp ""
+}
+
+
+test-ASSERT-FAIL-ufw-docker-delete-only-supports-allowed-rules() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker delete non-allow
+}
+test-ASSERT-FAIL-ufw-docker-delete-only-supports-allowed-rules-assert() {
+    die "\"delete\" command only support removing allowed rules"
+}
+
+
+function setup-ufw-docker--allow() {
+    load-ufw-docker-function ufw-docker--allow
+
+    @mocktrue docker inspect instance-name
+    @mock docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{"\n"}}{{end}}' instance-name === @stdout 172.18.0.3
+    @mock docker inspect --format='{{range $k, $v := .NetworkSettings.Networks}}{{printf "%s\n" $k}}{{end}}' instance-name === @stdout default
+    @mock docker inspect --format='{{range $p, $conf := .NetworkSettings.Ports}}{{with $conf}}{{$p}}{{"\n"}}{{end}}{{end}}' instance-name === @stdout 5000/tcp 8080/tcp 5353/udp
+}
+
+function setup-ufw-docker--allow--multinetwork() {
+    load-ufw-docker-function ufw-docker--allow
+
+    @mocktrue docker inspect instance-name
+    @mock docker inspect --format='{{range .NetworkSettings.Networks}}{{.IPAddress}}{{"\n"}}{{end}}' instance-name === @stdout 172.18.0.3 172.19.0.7
+    @mock docker inspect --format='{{range $k, $v := .NetworkSettings.Networks}}{{printf "%s\n" $k}}{{end}}' instance-name === @stdout default awesomenet
+    @mock docker inspect --format='{{range $p, $conf := .NetworkSettings.Ports}}{{with $conf}}{{$p}}{{"\n"}}{{end}}{{end}}' instance-name === @stdout 5000/tcp 8080/tcp 5353/udp
+}
+
+
+test-ufw-docker--allow-instance-not-found() {
+    setup-ufw-docker--allow
+
+    @mockfalse docker inspect invalid-instance
+    @mockfalse die "Docker instance \"invalid-instance\" doesn't exist."
+
+    ufw-docker--allow invalid-instance 80 tcp
+}
+test-ufw-docker--allow-instance-not-found-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--allow-instance-but-the-port-not-match() {
+    setup-ufw-docker--allow
+
+    ufw-docker--allow instance-name 80 tcp
+}
+test-ufw-docker--allow-instance-but-the-port-not-match-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--allow-instance-but-the-proto-not-match() {
+    setup-ufw-docker--allow
+
+    ufw-docker--allow instance-name 5353 tcp
+}
+test-ufw-docker--allow-instance-but-the-proto-not-match-assert() {
+    @do-nothing
+    @fail
+}
+
+
+test-ufw-docker--allow-instance-and-match-the-port() {
+    setup-ufw-docker--allow
+
+    ufw-docker--allow instance-name 5000 tcp
+}
+test-ufw-docker--allow-instance-and-match-the-port-assert() {
+    ufw-docker--add-rule instance-name 172.18.0.3 5000 tcp default
+}
+
+
+test-ufw-docker--allow-instance-all-published-port() {
+    setup-ufw-docker--allow
+
+    ufw-docker--allow instance-name "" ""
+}
+test-ufw-docker--allow-instance-all-published-port-assert() {
+    ufw-docker--add-rule instance-name 172.18.0.3 5000 tcp default
+    ufw-docker--add-rule instance-name 172.18.0.3 8080 tcp default
+    ufw-docker--add-rule instance-name 172.18.0.3 5353 udp default
+}
+
+
+test-ufw-docker--allow-instance-all-published-tcp-port() {
+    setup-ufw-docker--allow
+
+    ufw-docker--allow instance-name "" tcp
+}
+test-ufw-docker--allow-instance-all-published-tcp-port-assert() {
+    ufw-docker--add-rule instance-name 172.18.0.3 5000 tcp default
+    ufw-docker--add-rule instance-name 172.18.0.3 8080 tcp default
+    ufw-docker--add-rule instance-name 172.18.0.3 5353 udp default # FIXME
+}
+
+
+test-ufw-docker--allow-instance-all-published-port-multinetwork() {
+    setup-ufw-docker--allow--multinetwork
+
+    ufw-docker--allow instance-name "" ""
+}
+test-ufw-docker--allow-instance-all-published-port-multinetwork-assert() {
+    ufw-docker--add-rule  instance-name  172.18.0.3  5000  tcp  default
+    ufw-docker--add-rule  instance-name  172.19.0.7  5000  tcp  awesomenet
+    ufw-docker--add-rule  instance-name  172.18.0.3  8080  tcp  default
+    ufw-docker--add-rule  instance-name  172.19.0.7  8080  tcp  awesomenet
+    ufw-docker--add-rule  instance-name  172.18.0.3  5353  udp  default
+    ufw-docker--add-rule  instance-name  172.19.0.7  5353  udp  awesomenet
+}
+
+test-ufw-docker--allow-instance-all-published-port-multinetwork-select-network() {
+    setup-ufw-docker--allow--multinetwork
+
+    ufw-docker--allow instance-name "" "" awesomenet
+}
+test-ufw-docker--allow-instance-all-published-port-multinetwork-select-network-assert() {
+    ufw-docker--add-rule  instance-name  172.19.0.7  5000  tcp  awesomenet
+    ufw-docker--add-rule  instance-name  172.19.0.7  8080  tcp  awesomenet
+    ufw-docker--add-rule  instance-name  172.19.0.7  5353  udp  awesomenet
+}
+
+test-ufw-docker--add-rule-a-non-existing-rule() {
+    @mockfalse ufw-docker--list webapp 5000 tcp ""
+
+    load-ufw-docker-function ufw-docker--add-rule
+    ufw-docker--add-rule webapp 172.18.0.4 5000 tcp
+}
+test-ufw-docker--add-rule-a-non-existing-rule-assert() {
+    ufw route allow proto tcp from any to 172.18.0.4 port 5000 comment "allow webapp 5000/tcp"
+}
+
+test-ufw-docker--add-rule-a-non-existing-rule-with-network() {
+    @mockfalse ufw-docker--list webapp 5000 tcp default
+
+    load-ufw-docker-function ufw-docker--add-rule
+    ufw-docker--add-rule webapp 172.18.0.4 5000 tcp default
+}
+test-ufw-docker--add-rule-a-non-existing-rule-with-network-assert() {
+    ufw route allow proto tcp from any to 172.18.0.4 port 5000 comment "allow webapp 5000/tcp default"
+}
+
+
+test-ufw-docker--add-rule-modify-an-existing-rule() {
+    @mocktrue ufw-docker--list webapp 5000 tcp default
+    @mocktrue ufw --dry-run route allow proto tcp from any to 172.18.0.4 port 5000 comment "allow webapp 5000/tcp default"
+    @mockfalse grep "^Skipping"
+
+    load-ufw-docker-function ufw-docker--add-rule
+    ufw-docker--add-rule webapp 172.18.0.4 5000 tcp default
+}
+test-ufw-docker--add-rule-modify-an-existing-rule-assert() {
+    ufw-docker--delete webapp 5000 tcp default
+
+    ufw route allow proto tcp from any to 172.18.0.4 port 5000 comment "allow webapp 5000/tcp default"
+}
+
+
+test-ufw-docker--add-rule-skip-an-existing-rule() {
+    @mocktrue ufw-docker--list webapp 5000 tcp ""
+    @mocktrue ufw --dry-run route allow proto tcp from any to 172.18.0.4 port 5000 comment "allow webapp 5000/tcp"
+    @mocktrue grep "^Skipping"
+
+    load-ufw-docker-function ufw-docker--add-rule
+    ufw-docker--add-rule webapp 172.18.0.4 5000 tcp ""
+}
+test-ufw-docker--add-rule-skip-an-existing-rule-assert() {
+    @do-nothing
+}
+
+
+test-ufw-docker--add-rule-modify-an-existing-rule-without-port() {
+    @mocktrue ufw-docker--list webapp "" tcp ""
+
+    @mocktrue ufw --dry-run route allow proto tcp from any to 172.18.0.4 comment "allow webapp"
+    @mockfalse grep "^Skipping"
+
+    load-ufw-docker-function ufw-docker--add-rule
+
+    ufw-docker--add-rule webapp 172.18.0.4 "" tcp ""
+}
+test-ufw-docker--add-rule-modify-an-existing-rule-without-port-assert() {
+    ufw-docker--delete webapp "" tcp ""
+
+    ufw route allow proto tcp from any to 172.18.0.4 comment "allow webapp"
+}
+
+
+test-ufw-docker--instance-name-found-a-name() {
+    @mock docker inspect --format="{{.Name}}" foo
+    @mock sed -e 's,^/,,'
+    @mockfalse grep "^$GREP_REGEXP_INSTANCE_NAME\$"
+
+    @mock echo -n foo
+
+    load-ufw-docker-function ufw-docker--instance-name
+    ufw-docker--instance-name foo
+}
+test-ufw-docker--instance-name-found-a-name-assert() {
+    docker inspect --format="{{.Name}}" foo
+    @dryrun echo -n foo
+}
+
+
+test-ufw-docker--instance-name-found-an-id() {
+    @mock docker inspect --format="{{.Name}}" fooid
+    @mock sed -e 's,^/,,'
+    @mockfalse grep "^$GREP_REGEXP_INSTANCE_NAME\$"
+
+    load-ufw-docker-function ufw-docker--instance-name
+    ufw-docker--instance-name fooid
+}
+test-ufw-docker--instance-name-found-an-id-assert() {
+    docker inspect --format="{{.Name}}" fooid
+}
+
+
+test-ufw-docker--list-name() {
+    @mocktrue ufw status numbered
+    load-ufw-docker-function ufw-docker--list
+    ufw-docker--list foo
+}
+test-ufw-docker--list-name-assert() {
+    grep "# allow foo\\( [[:digit:]]\\+\\/\\(tcp\\|udp\\)\\)\\( [[:graph:]]*\\)\$"
+}
+
+test-ufw-docker--list-name-udp() {
+    @mocktrue ufw status numbered
+    load-ufw-docker-function ufw-docker--list
+    ufw-docker--list foo "" udp
+}
+test-ufw-docker--list-name-udp-assert() {
+    grep "# allow foo\\( [[:digit:]]\\+\\/\\(tcp\\|udp\\)\\)\\( [[:graph:]]*\\)\$"
+}
+
+
+test-ufw-docker--list-name-80() {
+    @mocktrue ufw status numbered
+    load-ufw-docker-function ufw-docker--list
+    ufw-docker--list foo 80
+}
+test-ufw-docker--list-name-80-assert() {
+    grep "# allow foo\\( 80\\/tcp\\)\\( [[:graph:]]*\\)\$"
+}
+
+
+test-ufw-docker--list-name-80-udp() {
+    @mocktrue ufw status numbered
+    load-ufw-docker-function ufw-docker--list
+    ufw-docker--list foo 80 udp
+}
+test-ufw-docker--list-name-80-udp-assert() {
+    grep "# allow foo\\( 80\\/udp\\)\\( [[:graph:]]*\\)\$"
+}
+
+
+test-ufw-docker--list-grep-without-network() {
+    @mocktrue ufw status numbered
+    @mockfalse grep "# allow foo\\( 80\\/udp\\)\\( [[:graph:]]*\\)\$"
+    load-ufw-docker-function ufw-docker--list
+    ufw-docker--list foo 80 udp
+}
+test-ufw-docker--list-grep-without-network-assert() {
+    grep "# allow foo\\( 80\\/udp\\)\$"
+}
+
+
+test-ufw-docker--list-grep-without-network-and-port() {
+    @mocktrue ufw status numbered
+    @mockfalse grep "# allow foo\\( 80\\/udp\\)\\( [[:graph:]]*\\)\$"
+    @mockfalse grep "# allow foo\\( 80\\/udp\\)\$"
+    load-ufw-docker-function ufw-docker--list
+    ufw-docker--list foo 80 udp
+}
+test-ufw-docker--list-grep-without-network-and-port-assert() {
+    grep "# allow foo\$"
+}
+
+
+test-ufw-docker--list-number() {
+    @mocktrue ufw-docker--list foo 53 udp
+
+    load-ufw-docker-function ufw-docker--list-number
+    ufw-docker--list-number foo 53 udp
+}
+test-ufw-docker--list-number-assert() {
+    sed -e 's/^\[[[:blank:]]*\([[:digit:]]\+\)\].*/\1/'
+}
+
+
+test-ufw-docker--delete-empty-result() {
+    @mock ufw-docker--list-number webapp 80 tcp === @stdout ""
+    @mockpipe sort -rn
+
+    load-ufw-docker-function ufw-docker--delete
+    ufw-docker--delete webapp 80 tcp
+}
+test-ufw-docker--delete-empty-result-assert() {
+    @do-nothing
+}
+
+
+test-ufw-docker--delete-all() {
+    @mock ufw-docker--list-number webapp 80 tcp === @stdout 5 8 9
+    @mockpipe sort -rn
+
+    load-ufw-docker-function ufw-docker--delete
+    ufw-docker--delete webapp 80 tcp
+}
+test-ufw-docker--delete-all-assert() {
+    ufw delete 5
+    ufw delete 8
+    ufw delete 9
+}

ufw-docker

@@ -2,13 +2,26 @@
 set -euo pipefail
 [[ -n "${DEBUG:-}" ]] && set -x
 
-PATH="/bin:/usr/bin:/sbin:/usr/sbin"
+LANG=en_US.UTF-8
+LANGUAGE=en_US:
+LC_ALL=en_US.UTF-8
+PATH="/bin:/usr/bin:/sbin:/usr/sbin:/snap/bin/"
 
 GREP_REGEXP_INSTANCE_NAME="[-_.[:alnum:]]\\+"
 DEFAULT_PROTO=tcp
 
 ufw_docker_agent=ufw-docker-agent
-ufw_docker_agent_image="${ufw_docker_agent_image:-chaifeng/${ufw_docker_agent}:181005}"
+ufw_docker_agent_image="${UFW_DOCKER_AGENT_IMAGE:-chaifeng/${ufw_docker_agent}:221002-nf_tables}"
+
+if [[ "${ufw_docker_agent_image}" = *-@(legacy|nf_tables) ]]; then
+    if iptables --version | grep -F '(legacy)' &>/dev/null; then
+        ufw_docker_agent_image="${ufw_docker_agent_image%-*}-legacy"
+    else
+        ufw_docker_agent_image="${ufw_docker_agent_image%-*}-nf_tables"
+    fi
+fi
+
+test -n "$ufw_docker_agent_image"
 
 function ufw-docker--status() {
     ufw-docker--list "$GREP_REGEXP_INSTANCE_NAME"
@@ -18,12 +31,20 @@ function ufw-docker--list() {
     local INSTANCE_NAME="$1"
     local INSTANCE_PORT="${2:-}"
     local PROTO="${3:-${DEFAULT_PROTO}}"
+    local NETWORK="${4:-}"
 
     if [[ -z "$INSTANCE_PORT" ]]; then
         INSTANCE_PORT="[[:digit:]]\\+"
         PROTO="\\(tcp\\|udp\\)"
     fi
-    ufw status numbered | grep "# allow ${INSTANCE_NAME}\\( ${INSTANCE_PORT}\\/${PROTO}\\)\\?\$"
+
+    if [[ -z "$NETWORK" ]]; then
+       NETWORK="[[:graph:]]*"
+    fi
+
+    ufw status numbered | grep "# allow ${INSTANCE_NAME}\\( ${INSTANCE_PORT}\\/${PROTO}\\)\\( ${NETWORK}\\)\$" ||  \
+    ufw status numbered | grep "# allow ${INSTANCE_NAME}\\( ${INSTANCE_PORT}\\/${PROTO}\\)\$" || \
+    ufw status numbered | grep "# allow ${INSTANCE_NAME}\$"
 }
 
 function ufw-docker--list-number() {
@@ -41,6 +62,7 @@ function ufw-docker--allow() {
     local INSTANCE_NAME="$1"
     local INSTANCE_PORT="$2"
     local PROTO="$3"
+    local NETWORK="${4:-}"
 
     docker inspect "$INSTANCE_NAME" &>/dev/null ||
         die "Docker instance \"$INSTANCE_NAME\" doesn't exist."
@@ -49,6 +71,7 @@ function ufw-docker--allow() {
 
     [[ -z "${INSTANCE_IP_ADDRESSES:-}" ]] && die "Could not find a running instance \"$INSTANCE_NAME\"."
 
+    mapfile -t INSTANCE_NETWORK_NAMES < <(docker inspect --format='{{range $k, $v := .NetworkSettings.Networks}}{{printf "%s\n" $k}}{{end}}' "$INSTANCE_NAME" 2>/dev/null | remove_blank_lines)
     mapfile -t PORT_PROTO_LIST < <(docker inspect --format='{{range $p, $conf := .NetworkSettings.Ports}}{{with $conf}}{{$p}}{{"\n"}}{{end}}{{end}}' "$INSTANCE_NAME" | remove_blank_lines)
 
     if [[ -z "${PORT_PROTO_LIST:-}" ]]; then
@@ -59,8 +82,14 @@ function ufw-docker--allow() {
     RETVAL=1
     for PORT_PROTO in "${PORT_PROTO_LIST[@]}"; do
         if [[ -z "$INSTANCE_PORT" || "$PORT_PROTO" = "${INSTANCE_PORT}/${PROTO}" ]]; then
+            ITER=0
             for IP in "${INSTANCE_IP_ADDRESSES[@]}"; do
-                ufw-docker--add-rule "$INSTANCE_NAME" "$IP" "${PORT_PROTO%/*}" "${PORT_PROTO#*/}"
+                INSTANCE_NETWORK="${INSTANCE_NETWORK_NAMES[$ITER]}"
+                ITER=$((ITER+1))
+                if [[ -n "$NETWORK" ]] && [[ "$NETWORK" != "$INSTANCE_NETWORK" ]]; then
+                    continue
+                fi
+                ufw-docker--add-rule "$INSTANCE_NAME" "$IP" "${PORT_PROTO%/*}" "${PORT_PROTO#*/}" "${INSTANCE_NETWORK}"
                 RETVAL="$?"
             done
         fi
@@ -89,10 +118,11 @@ function ufw-docker--add-rule() {
     local INSTANCE_IP_ADDRESS="$2"
     local PORT="$3"
     local PROTO="$4"
+    local NETWORK="${5:-}"
 
     declare comment
 
-    echo "allow ${INSTANCE_NAME} ${PORT}/${PROTO}"
+    echo "allow ${INSTANCE_NAME} ${PORT}/${PROTO} ${NETWORK}"
     typeset -a UFW_OPTS
     UFW_OPTS=(route allow proto "${PROTO}"
               from any to "$INSTANCE_IP_ADDRESS")
@@ -101,12 +131,15 @@ function ufw-docker--add-rule() {
         UFW_OPTS+=(port "${PORT}")
         comment="$comment ${PORT}/${PROTO}"
     }
+    [[ -n "$NETWORK" ]] && {
+        comment="$comment ${NETWORK}"
+    }
     UFW_OPTS+=(comment "$comment")
 
-    if ufw-docker--list "$INSTANCE_NAME" "$PORT" "$PROTO" &>/dev/null; then
+    if ufw-docker--list "$INSTANCE_NAME" "$PORT" "$PROTO" "$NETWORK" &>/dev/null; then
         ufw --dry-run "${UFW_OPTS[@]}" | grep "^Skipping" && return 0
         err "Remove outdated rule."
-        ufw-docker--delete "$INSTANCE_NAME" "$PORT" "$PROTO"
+        ufw-docker--delete "$INSTANCE_NAME" "$PORT" "$PROTO" "$NETWORK"
     fi
     echo ufw "${UFW_OPTS[@]}"
     ufw "${UFW_OPTS[@]}"
@@ -256,50 +289,101 @@ function ufw-docker--raw-command() {
     ufw "$@"
 }
 
+after_rules="/etc/ufw/after.rules"
+
+function ufw-docker--check() {
+    err "\\n########## iptables -n -L DOCKER-USER ##########"
+    iptables -n -L DOCKER-USER
+
+    err "\\n\\n########## diff $after_rules ##########"
+    ufw-docker--check-install && err "\\nCheck done."
+}
+
+declare -a files_to_be_deleted
+
+function rm-on-exit() {
+    [[ $# -gt 0 ]] && files_to_be_deleted+=("$@")
+}
+
+function on-exit() {
+    for file in "${files_to_be_deleted[@]:-}"; do
+        [[ -f "$file" ]] && rm -r "$file"
+    done
+    files_to_be_deleted=()
+}
+
+trap on-exit EXIT INT TERM QUIT ABRT ERR
+
+function ufw-docker--check-install() {
+    after_rules_tmp="${after_rules_tmp:-$(mktemp)}"
+    rm-on-exit "$after_rules_tmp"
+
+    sed "/^# BEGIN UFW AND DOCKER/,/^# END UFW AND DOCKER/d" "$after_rules" > "$after_rules_tmp"
+    >> "${after_rules_tmp}" cat <<-\EOF
+	# BEGIN UFW AND DOCKER
+	*filter
+	:ufw-user-forward - [0:0]
+	:ufw-docker-logging-deny - [0:0]
+	:DOCKER-USER - [0:0]
+	-A DOCKER-USER -j ufw-user-forward
+
+	-A DOCKER-USER -j RETURN -s 10.0.0.0/8
+	-A DOCKER-USER -j RETURN -s 172.16.0.0/12
+	-A DOCKER-USER -j RETURN -s 192.168.0.0/16
+
+	-A DOCKER-USER -p udp -m udp --sport 53 --dport 1024:65535 -j RETURN
+
+	-A DOCKER-USER -j ufw-docker-logging-deny -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 192.168.0.0/16
+	-A DOCKER-USER -j ufw-docker-logging-deny -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 10.0.0.0/8
+	-A DOCKER-USER -j ufw-docker-logging-deny -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -d 172.16.0.0/12
+	-A DOCKER-USER -j ufw-docker-logging-deny -p udp -m udp --dport 0:32767 -d 192.168.0.0/16
+	-A DOCKER-USER -j ufw-docker-logging-deny -p udp -m udp --dport 0:32767 -d 10.0.0.0/8
+	-A DOCKER-USER -j ufw-docker-logging-deny -p udp -m udp --dport 0:32767 -d 172.16.0.0/12
+
+	-A DOCKER-USER -j RETURN
+
+	-A ufw-docker-logging-deny -m limit --limit 3/min --limit-burst 10 -j LOG --log-prefix "[UFW DOCKER BLOCK] "
+	-A ufw-docker-logging-deny -j DROP
+
+	COMMIT
+	# END UFW AND DOCKER
+	EOF
+
+    diff -u --color=auto "$after_rules" "$after_rules_tmp"
+}
+
 function ufw-docker--install() {
-	if ! grep "^# BEGIN UFW AND DOCKER\$" /etc/ufw/after.rules &>/dev/null; then
-		err "Back up /etc/ufw/after.rules"
-		cp /etc/ufw/after.rules /etc/ufw/after.rules-ufw-docker~"$(date '+%Y-%m-%d-%H%M%S').bak"
-		cat <<-\EOF | tee -a /etc/ufw/after.rules
-		# BEGIN UFW AND DOCKER
-		*filter
-		:ufw-user-forward - [0:0]
-		:DOCKER-USER - [0:0]
-		-A DOCKER-USER -j RETURN -s 10.0.0.0/8
-		-A DOCKER-USER -j RETURN -s 172.16.0.0/12
-		-A DOCKER-USER -j RETURN -s 192.168.0.0/16
-
-		-A DOCKER-USER -j ufw-user-forward
-
-		-A DOCKER-USER -j DROP -d 192.168.0.0/16 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN
-		-A DOCKER-USER -j DROP -d 10.0.0.0/8 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN
-		-A DOCKER-USER -j DROP -d 172.16.0.0/12 -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN
-		-A DOCKER-USER -j DROP -d 192.168.0.0/16 -p udp -m udp --dport 0:32767
-		-A DOCKER-USER -j DROP -d 10.0.0.0/8 -p udp -m udp --dport 0:32767
-		-A DOCKER-USER -j DROP -d 172.16.0.0/12 -p udp -m udp --dport 0:32767
-
-		-A DOCKER-USER -j RETURN
-		COMMIT
-		# END UFW AND DOCKER
-		EOF
-		err "Please restart UFW service manually."
-	fi
+    if ! ufw-docker--check-install; then
+        local after_rules_bak
+        after_rules_bak="${after_rules}-ufw-docker~$(date '+%Y-%m-%d-%H%M%S')~"
+        err "\\nBacking up $after_rules to $after_rules_bak"
+        cp "$after_rules" "$after_rules_bak"
+        cat "$after_rules_tmp" > "$after_rules"
+        err "Please restart UFW service manually by using the following command:"
+        if type systemctl &>/dev/null; then
+            err "    sudo systemctl restart ufw"
+        else
+            err "    sudo service ufw restart"
+        fi
+    fi
 }
 
 function ufw-docker--help() {
-	cat <<-EOF >&2
+    cat <<-EOF >&2
 	Usage:
-	  ufw-docker <list|allow> [docker-instance-id-or-name [port[/tcp|/udp]]]
-	  ufw-docker delete allow [docker-instance-id-or-name [port[/tcp|/udp]]]
+	  ufw-docker <list|allow> [docker-instance-id-or-name [port[/tcp|/udp]] [network]]
+	  ufw-docker delete allow [docker-instance-id-or-name [port[/tcp|/udp]] [network]]
 
 	  ufw-docker service allow <swarm-service-id-or-name <port</tcp|/udp>>>
 	  ufw-docker service delete allow <swarm-service-id-or-name>
 
-	  ufw-docker <status|install|help>
+	  ufw-docker <status|install|check|help>
 
 	Examples:
 	  ufw-docker help
-	  ufw-docker install
+
+	  ufw-docker check           # Check the installation of firewall rules
+	  ufw-docker install         # Install firewall rules
 
 	  ufw-docker status
 
@@ -309,10 +393,11 @@ function ufw-docker--help() {
 	  ufw-docker allow httpd
 	  ufw-docker allow httpd 80
 	  ufw-docker allow httpd 80/tcp
+	  ufw-docker allow httpd 80/tcp default
 
 	  ufw-docker delete allow httpd
 	  ufw-docker delete allow httpd 80/tcp
-
+          ufw-docker delete allow httpd 80/tcp default
 
 	  ufw-docker service allow httpd 80/tcp
 
@@ -325,7 +410,7 @@ function remove_blank_lines() {
 }
 
 function err() {
-    echo "$@" >&2
+    echo -e "$@" >&2
 }
 
 function die() {
@@ -333,8 +418,14 @@ function die() {
     exit 1
 }
 
+# __main__
+
 if ! ufw status 2>/dev/null | grep -Fq "Status: active" ; then
-    die "UFW is disabled or you are not root user."
+    die "UFW is disabled or you are not root user, or mismatched iptables legacy/nf_tables, current $(iptables --version)"
+fi
+
+if ! docker -v &> /dev/null; then
+  die "Docker executable not found."
 fi
 
 ufw_action="${1:-help}"
@@ -362,16 +453,19 @@ case "$ufw_action" in
         if [[ "$INSTANCE_PORT" = */udp ]]; then
             PROTO=udp
         fi
+        shift || true
+
+        NETWORK="${1:-}"
 
         INSTANCE_PORT="${INSTANCE_PORT%/*}"
 
-        "ufw-docker--$ufw_action" "$INSTANCE_NAME" "$INSTANCE_PORT" "$PROTO"
+        "ufw-docker--$ufw_action" "$INSTANCE_NAME" "$INSTANCE_PORT" "$PROTO" "$NETWORK"
         ;;
     service|raw-command|add-service-rule)
         shift || true
         "ufw-docker--$ufw_action" "$@"
         ;;
-    status|install)
+    status|install|check)
         ufw-docker--"$ufw_action"
         ;;
     *)