How to Install and Test the aURIBL / AXI-URIBL Filter

This document describes how to install and test all the components needed for the Axigen aURIBL filter on a Linux server running an Axigen 10.3 version or later.

In case your Axigen working directory is not the default one (/var/opt/axigen), please adapt the instructions below to your specific location.

Solution

Run these steps as root:

1. Install python prerequisites

  • RPM based systems: # yum update
    • For older systems with Python 2:  # yum install python-pip
    • For newer systems with Python 3:  # yum install python3-pip

     

  • Deb based systems: # apt update
    # apt install python-pip
  • Update PIP (Package Installer for Python) and install Beautiful Soup (Python HTML parsing library):
    • For older systems with Python 2:  # pip install --upgrade pip
      # pip install bs4
    • For newer systems with Python 3:  # pip3 install --upgrade pip
      # pip3 install bs4


2. Download filter components

# cd /var/opt/axigen/filters 
# curl -L https://support.axigen.com/axi-uribl/axi-uribl.afsl -O 
# chown axigen:axigen axi-uribl.afsl 
# mkdir -p /opt/axigen/scripts 
# cd /opt/axigen/scripts 
# curl -L https://support.axigen.com/axi-uribl/axi-uribl.py -O 
# chmod +x axi-uribl.py 
# curl -L https://support.axigen.com/axi-uribl/config_uribl.py -O


3. Configure the filter

Edit config_uribl.py and change the following parameters: 

  • > OUR_DOMAINS with the values you like to whitelist (if any) 
  • > AURIBL_KEY with the value specific to your project

Please only use the first part of the license (like auribl-XXXXXXXX-XXXXXXXX-XXXXXXXX) 


4. Check to see if the filter is properly configured

# cd /opt/axigen/scripts 
# ./axi-uribl.py check test test-test-test 127.0.0.2 2.0.0.127 127.0.0.127 
Command mode detected - checking domains: ['test', 'test-test-test', '127.0.0.2', '2.0.0.127', '127.0.0.127'] 
test = 127.0.0.2 (aURIBL) 
127.0.0.127 = 127.0.0.2 (aURIBL) 
test-test-test = 127.0.0.2 (aURIBL) 
2.0.0.127 = 127.0.0.2 (aURIBL)

Only continue if you are receiving similar results (otherwise, contact the Axigen support team for further clarifications).


5. Configure Axigen

# cd /var/opt/axigen/run 
# cp -p axigen.cfg axigen.cfg.backup-$(date '+%s') 
# sed -i 's|socketFilters = (|socketFilters = (\n\t{\n\t\t'\ 
'name = "AXI-URIBL"\n\t\taddress = "inet://127.0.0.1:8899"\n\t\t'\ 
'protocolFile = "/var/opt/axigen/filters/axi-uribl.afsl"\n\t\t'\ 
'idleTimeout = 300\n\t\tactionOnMatch = pass\n\t\t'\ 
'maxConnections = 10\n\t\tmaxMessageSize = 10240\n\t}|' axigen.cfg

If the default prefix [SUSPECT] has to be changed, this could be done by editing the specific Axigen AFSL file: filters/axiuribl.afsl


6. Configure the AXI-URIBL service

# cat << 'EOF' > /etc/systemd/system/axi-uribl.service 
[Unit] 
Description=Axigen URIBL service 
After=network.target 

[Service] 
Type=simple 
Restart=always 
RestartSec=1 
StartLimitInterval=0 
ExecStart=/opt/axigen/scripts/axi-uribl.py 2> >(logger -p mail.err) > >(/dev/null) 

[Install] 
WantedBy=multi-user.target 
EOF


7. Enable, start, and check the status of the new service

# systemctl daemon-reload 
# systemctl enable axi-uribl 
# systemctl start axi-uribl 
# systemctl status axi-uribl


8. Check to see if the service is running properly by sending a ping command and receiving pong answer

# telnet 0 8899 
Trying 0.0.0.0... 
Connected to 0. 
Escape character is '^]'. 
welcome 0.0.13 on 140529880467200:00000001 
ping 
pong 
quit 
Connection closed by foreign host.


9. Reload the configuration for the Axigen service

# /etc/init.d/axigen reload


10. Enable the AXI-URIBL filter from the Axigen WebAdmin

To enable the filter, log into WebAdmin and navigate to Security & FilteringAntivirus & AntiSpamSupported Applications.


11. Check that the filter is running correctly

Send an internal message that includes https://test-test-test in its body 
Expected results in message headers (check out the two examples below):

Subject: >> Prefixed with [SUSPECT] 
X-AXI-URIBL: 1 
X-AXI-URIBL-INFO: test-test-test = 127.0.0.2 (aURIBL

These are two examples with their traces in the logs:

  • Syslog – /var/log/maillog Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 Info: **\
    Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 Connected with 127.0.0.1:55094
    Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 filter|/var/opt/axigen//queue
    /03/D1AD4.03|/var/opt/axigen//queue/03/D1AD4.04|5.10.20.40|mail.domain.org|sender@domain.org
    Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 test-test-test = 127.0.0.2
    (aURIBL)
    Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 File /var/opt/axigen//queue/03
    /D1AD4.03 processed in 130 ms result: 1 (2,1)
    Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 Disconnected from 127.0.0.1:
    55094
    Apr 23 16:48:36 mail axi-uribl.py[8257]: 140529880467200:00000002 Info: **/
    ...
    Apr 23 16:51:32 mail axi-uribl.py[8257]: 140529880467200:00000005 Info: *******\
    Apr 23 16:51:32 mail axi-uribl.py[8257]: 140529880467200:00000005 Connected with 127.0.0.1:33532
    Apr 23 16:51:32 mail axi-uribl.py[8257]: 140529880467200:00000005 filter|/var/opt/axigen//queue
    /27/D9AAB.02|/var/opt/axigen//queue/27/D9AAB.03|193.193.193.193|smtp.company.com|billing@company.
    com
    Apr 23 16:51:32 mail axi-uribl.py[8257]: 140529880467200:00000005 File /var/opt/axigen//queue/27
    /D9AAB.02 processed in 407 ms result: 0 (26,7)
    Apr 23 16:51:32 mail axi-uribl.py[8257]: 140529880467200:00000005 Disconnected from 127.0.0.1:
    33532
    Apr 23 16:51:32 mail axi-uribl.py[8257]: 140529880467200:00000005 Info: *******/

    Observe the result format of x (y,z) meaning that:

    • y individual URLs where detected
    • out of which there are z unique hostnames (only these ones are checked into the aURIBL DNS service)
    • out of which x are found to be suspect.

    The first message was detected as suspect (x=1, y=2, z=1) and the second as clean (x=0, y=26, z=7).

    Any message filtered by AXI-URIBL will have at least an X-AXI-URIBL header, set with the value of x.
     

  • Axigen Processing log 2020-04-23 16:48:36 +0300 08 mail PROCESSING:00031AD4: Start filter AXI-URIBL of type socket
    filter from server
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: << welcome 0.0.12 on 140529880467200:
    00000002
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> filter|
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> /var/opt/axigen//queue/03/D1AD4.03
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> |
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> /var/opt/axigen//queue/03/D1AD4.04
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> |
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> 5.10.20.40
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> |
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> mail.domain.org
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> |
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: >> sender@domain.org
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: << info: X-AXI-URIBL-INFO: test-test-test
    = 127.0.0.2 (aURIBL)
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: << info: X-AXI-URIBL: 1
    2020-04-23 16:48:36 +0300 16 mail PROCESSING:00031AD4: << present
    2020-04-23 16:48:36 +0300 08 mail PROCESSING:00031AD4: Filter AXI-URIBL(127.0.0.1:8899):[PASS]:
    pass - present
    2020-04-23 16:48:36 +0300 08 mail PROCESSING:00031AD4: Finished filtering mail object 031AD4
    with filter: AXI-URIBL of type socket filter from server
    ...
    2020-04-23 16:51:32 +0300 08 mail PROCESSING:00279AAB: Start filter AXI-URIBL of type socket
    filter from server
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: << welcome 0.0.12 on 140529880467200:
    00000005
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> filter|
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> /var/opt/axigen//queue/27/D9AAB.02
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> |
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> /var/opt/axigen//queue/27/D9AAB.03
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> |
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> 193.193.193.193
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> |
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> smtp.company.com
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> |
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: >> billing@company.com
    2020-04-23 16:51:32 +0300 16 mail PROCESSING:00279AAB: << done
    2020-04-23 16:51:32 +0300 08 mail PROCESSING:00279AAB: Filter AXI-URIBL(127.0.0.1:8899):[PASS]:
    pass - no changes
    2020-04-23 16:51:32 +0300 08 mail PROCESSING:00279AAB: Finished filtering mail object 279AAB
    with filter: AXI-URIBL of type socket filter from server