Installing dynamic WAF module for NGINX Plus¶

These instructions describe the steps to install Wallarm WAF as a dynamic module for the official commercial version of NGINX Plus.

apt list wallarm-node

apt list wallarm-node

yum list wallarm-node

# run from the server with installed WAF node
apt list wallarm-node-nginx
# run from the server with installed postanalytics
apt list wallarm-node-tarantool

# run from the server with installed WAF node
apt list wallarm-node-nginx
# run from the server with installed postanalytics
apt list wallarm-node-tarantool

# run from the server with installed WAF node
yum list wallarm-node-nginx
# run from the server with installed postanalytics
yum list wallarm-node-tarantool

Requirements¶

• Access to the account with the Administrator role and two‑factor authentication disabled in Wallarm Console for the EU Cloud or US Cloud

• SELinux disabled or configured upon the instruction

• Executing all commands as a superuser (e.g. root)

• For the request processing and postanalytics on different servers: postanalytics installed on the separate server upon the instruction

• Access to https://repo.wallarm.com to download packages. Ensure the access is not blocked by a firewall

• Access to https://api.wallarm.com:444 for working with EU Wallarm Cloud or to https://us1.api.wallarm.com:444 for working with US Wallarm Cloud. If access can be configured only via the proxy server, use the instruction

• Installed text editor vim, nano or any other. In the instruction, vim is used

Installation options¶

The processing of requests in the WAF is divided into two stages:

• Primary processing in the NGINX-Wallarm module. The processing is not memory demanding and can be put on frontend servers without changing the server requirements.

• Statistical analysis of the processed requests in the postanalytics module. Postanalytics is memory demanding, which may require changes in the server configuration or installation of postanalytics on a separate server.

Depending on the system architecture, the NGINX-Wallarm and postanalytics modules can be installed on the same server or on different servers. Installation commands for both options are described in the further instructions.

Installation¶

1. Install NGINX Plus and dependencies¶

Install NGINX Plus and its dependencies using these official NGINX instructions.

2. Add Wallarm WAF repositories¶

Wallarm WAF is installed and updated from the Wallarm repositories. To add repositories, use the commands for your platform:

sudo apt install dirmngr
curl -fsSL https://repo.wallarm.com/wallarm.gpg | sudo apt-key add -
sh -c "echo 'deb http://repo.wallarm.com/debian/wallarm-node stretch/2.14/' | sudo tee /etc/apt/sources.list.d/wallarm.list"
sudo apt update

sudo apt install dirmngr
curl -fsSL https://repo.wallarm.com/wallarm.gpg | sudo apt-key add -
sh -c "echo 'deb http://repo.wallarm.com/debian/wallarm-node buster/2.14/' | sudo tee /etc/apt/sources.list.d/wallarm.list"
sudo apt update

curl -fsSL https://repo.wallarm.com/wallarm.gpg | sudo apt-key add -
sh -c "echo 'deb http://repo.wallarm.com/ubuntu/wallarm-node xenial/2.14/' | sudo tee /etc/apt/sources.list.d/wallarm.list"
sudo apt update

curl -fsSL https://repo.wallarm.com/wallarm.gpg | sudo apt-key add -
sh -c "echo 'deb http://repo.wallarm.com/ubuntu/wallarm-node bionic/2.14/' | sudo tee /etc/apt/sources.list.d/wallarm.list"
sudo apt update

sudo yum install --enablerepo=extras -y epel-release centos-release-SCL
sudo rpm -i https://repo.wallarm.com/centos/wallarm-node/6/2.14/x86_64/Packages/wallarm-node-repo-1-5.el6.noarch.rpm

sudo yum install -y epel-release
sudo rpm -i https://repo.wallarm.com/centos/wallarm-node/7/2.14/x86_64/Packages/wallarm-node-repo-1-5.el7.noarch.rpm

sudo yum install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
sudo rpm -i https://repo.wallarm.com/centos/wallarm-node/7/2.14/x86_64/Packages/wallarm-node-repo-1-5.el7.noarch.rpm

3. Install Wallarm WAF packages¶

Request processing and postanalytics on the same server¶

To run postanalytics and process the requests on the same server, the following packages are required:

• nginx-plus-module-wallarm for the NGINX Plus-Wallarm module

• wallarm-node for the postanalytics module, Tarantool database, and additional NGINX Plus-Wallarm packages

sudo apt install --no-install-recommends wallarm-node nginx-plus-module-wallarm

sudo apt install --no-install-recommends wallarm-node nginx-plus-module-wallarm

sudo yum install wallarm-node nginx-plus-module-wallarm

Request processing and postanalytics on different servers¶

To run postanalytics and process the requests on different servers, the following packages are required:

• wallarm-node-nginx and nginx-plus-module-wallarm for the NGINX Plus-Wallarm module

  Debian

  sudo apt install --no-install-recommends wallarm-node-nginx nginx-plus-module-wallarm
  

  Ubuntu

  sudo apt install --no-install-recommends wallarm-node-nginx nginx-plus-module-wallarm
  

  CentOS or Amazon Linux 2

  sudo yum install wallarm-node-nginx nginx-plus-module-wallarm
  

• wallarm-node-tarantool on the separate server for the postanalytics module and Tarantool database (installation steps are described in the instruction)

4. Connect the Wallarm WAF module¶

1. Open the file /etc/nginx/nginx.conf:

   sudo vim /etc/nginx/nginx.conf
   

2. Add the following directive right after the worker_processes directive:

   load_module modules/ngx_http_wallarm_module.so;
   

   Configuration example with the added directive:

   user  nginx;
   worker_processes  auto;
   load_module modules/ngx_http_wallarm_module.so;
   
   error_log  /var/log/nginx/error.log notice;
   pid        /var/run/nginx.pid;
   

3. Copy the configuration files for the system setup:

   sudo cp /usr/share/doc/nginx-plus-module-wallarm/examples/*.conf /etc/nginx/conf.d/
   

5. Connect the WAF node to Wallarm Cloud¶

The WAF node interacts with the Wallarm Cloud. To connect the WAF node to the Cloud, proceed with the following steps:

1. Make sure that your Wallarm account has the Administrator role enabled and two-factor authentication disabled in Wallarm Console.

   You can check mentioned settings by navigating to the users list in the EU Cloud or US Cloud.

   

2. Run the addnode script in a system with the installed WAF node:

   EU Cloud

   sudo /usr/share/wallarm-common/addnode
   

   US Cloud

   sudo /usr/share/wallarm-common/addnode -H us1.api.wallarm.com
   

3. Input an email and password of you account in Wallarm Console.

4. Input the WAF node name or click Enter to use automatically generated name.

5. Open Wallarm Console → Node section in the EU Cloud or US Cloud and ensure a new WAF node is added to the list.

6. Update Wallarm WAF configuration¶

Main configuration files of NGINX and Wallarm WAF node are located in the directories:

• /etc/nginx/conf.d/default.conf with NGINX settings

• /etc/nginx/conf.d/wallarm.conf with global WAF node settings

  The file is used for settings applied to all domains. To apply different settings to different domain groups, use the file default.conf or create new configuration files for each domain group (for example, example.com.conf and test.com.conf). More detailed information about NGINX configuration files is available in the official NGINX documentation.

• /etc/nginx/conf.d/wallarm‑status.conf with WAF node monitoring settings. Detailed description is available by the link

• /etc/default/wallarm-tarantool or /etc/sysconfig/wallarm-tarantool with the Tarantool database settings

Request filtering mode¶

By default, WAF node is in the status off and does not filter requests. Change the filtering mode on the NGINX settings level to block requests with attacks:

1. Open the file /etc/nginx/conf.d/default.conf:

   sudo vim /etc/nginx/conf.d/default.conf
   

2. Add the line wallarm_mode block; to the server block:

server {
    # port for which requests are filtered
    listen       80;
    # domain for which requests are filtered
    server_name  localhost;
    # WAF node mode
    wallarm_mode block;

    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;
    }

    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }
}

Memory¶

The WAF node uses the in-memory storage Tarantool. The recommended memory size for Tarantool is 75% of the total server memory. To allocate memory for Tarantool:

1. Open the Tarantool configuration file in the editing mode:

   Debian

   sudo vim /etc/default/wallarm-tarantool
   

   Ubuntu

   sudo vim /etc/default/wallarm-tarantool
   

   CentOS or Amazon Linux 2

   sudo vim /etc/sysconfig/wallarm-tarantool
   

2. Specify memory size in GB in the SLAB_ALLOC_ARENA directive. For example, 24 GB:

   SLAB_ALLOC_ARENA=24
   

   Detailed recommendations about allocating memory for Tarantool are described in the instruction.

3. To apply changes, restart Tarantool:

   Debian

   sudo systemctl restart wallarm-tarantool
   

   Ubuntu

   sudo systemctl restart wallarm-tarantool
   

   CentOS 6.x

   sudo service wallarm-tarantool restart
   

   CentOS 7.x or Amazon Linux 2

   sudo systemctl restart wallarm-tarantool
   

Address of the separate postanalytics server¶

Add postanalytics server addresses to the file /etc/nginx/conf.d/wallarm.conf:

upstream wallarm_tarantool {
    server <ip1>:3313 max_fails=0 fail_timeout=0 max_conns=1;
    server <ip2>:3313 max_fails=0 fail_timeout=0 max_conns=1;

    keepalive 2;
    }

    # omitted

wallarm_tarantool_upstream wallarm_tarantool;

• max_conns value must be specified for each of the upstream Tarantool servers to prevent the creation of excessive connections.

• keepalive value must not be lower than the number of the Tarantool servers.

Other configurations¶

To update other NGINX and Wallarm WAF cconfigurations, use the NGINX documentation and the list of available Wallarm WAF directives.

7. Restart NGINX Plus¶

usermod -aG wallarm <user_name>;

sudo systemctl restart nginx

sudo service nginx restart

sudo service nginx restart

sudo systemctl restart nginx

8. Test Wallarm WAF operation¶

1. Get the WAF node statistics:

   curl http://127.0.0.8/wallarm-status
   

   The request will return statistics about analyzed requests. Response format is provided below, more detailed description of parameters is available by the link.
   

   { "requests":0,"attacks":0,"blocked":0,"abnormal":0,"tnt_errors":0,"api_errors":0,
   "requests_lost":0,"segfaults":0,"memfaults":0,"softmemfaults":0,"time_detect":0,"db_id":46,
   "lom_id":16767,"proton_instances": { "total":1,"success":1,"fallback":0,"failed":0 },
   "stalled_workers_count":0,"stalled_workers":[] }
   

2. Send the request with test SQLI and XSS attacks to the application address:

   curl http://localhost/?id='or+1=1--a-<script>prompt(1)</script>'
   

   WAF node will block the request and the code 403 Forbidden will be returned in the response to the request.

3. Send the request to wallarm-status and ensure the values of parameters requests and attacks increased:

   curl http://127.0.0.8/wallarm-status
   

4. Open Wallarm Console → Events section in the EU Cloud or US Cloud and ensure attacks are displayed in the list.
   

   

Settings customization¶

Dynamic Wallarm WAF module with default settings is installed for NGINX Plus. To customize Wallarm WAF settings, use the available directives.

Common customization options:

• Configuration of the filtering mode

• Logging WAF node variables

• Using the balancer of the proxy server behind the WAF node

• Adding Wallarm Scanner addresses to the whitelist in the block filtering mode

• Limiting the single request processing time in the directive wallarm_process_time_limit

• Limiting the server reply waiting time in the NGINX directive proxy_read_timeout

• Limiting the maximum request size in the NGINX directive client_max_body_size