Lesson 9.7: Manage SELinux port labels

# Http port default is 80
[root@server ~]# netstat -tnl | grep 80 
tcp6       0      0 :::80                   :::*                    LISTEN    
 
# Modifing the port from 80 to 8098
[root@server ~]# vi /etc/httpd/conf/httpd.conf 
Listen 8098
 
# If the SElinux is in enforcing state then, if port is changed, then the information should be passed to SELInux.
# Else the httpd service will not start and fail
[root@server ~]# getenforce 
Enforcing
[root@server ~]# systemctl restart httpd
Job for httpd.service failed because the control process exited with error code.
See "systemctl status httpd.service" and "journalctl -xeu httpd.service" for details.
[root@server ~]# systemctl status httpd 
× httpd.service - The Apache HTTP Server
     Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; preset: disabled)
     Active: failed (Result: exit-code) since Mon 2024-09-30 10:40:09 +0545; 10s ago
   Duration: 26min 34.052s
       Docs: man:httpd.service(8)
    Process: 5296 ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND (code=exited, status=1/FAILURE)
   Main PID: 5296 (code=exited, status=1/FAILURE)
     Status: "Reading configuration..."
        CPU: 29ms
 
Sep 30 10:39:41 server systemd[1]: Starting The Apache HTTP Server...
Sep 30 10:40:09 server httpd[5296]: AH00558: httpd: Could not reliably determine the server's fully quali>
Sep 30 10:40:09 server httpd[5296]: (13)Permission denied: AH00072: make_sock: could not bind to address >
Sep 30 10:40:09 server httpd[5296]: (13)Permission denied: AH00072: make_sock: could not bind to address >
Sep 30 10:40:09 server httpd[5296]: no listening sockets available, shutting down
Sep 30 10:40:09 server httpd[5296]: AH00015: Unable to open logs
Sep 30 10:40:09 server systemd[1]: httpd.service: Main process exited, code=exited, status=1/FAILURE
Sep 30 10:40:09 server systemd[1]: httpd.service: Failed with result 'exit-code'.
Sep 30 10:40:09 server systemd[1]: Failed to start The Apache HTTP Server.'
 
# A Reference of the code is shown in this file /etc/ssh/sshd_config
# If you want to change the port on a SELinux system, you have to tell SELinux about this change.
# semanage port -a -t ssh_port_t -p tcp #PORTNUMBER
 
[root@server ssh]# semanage port -a -t http_port_t -p tcp 8098
 
# Now the service will run 
[root@server ssh]# systemctl restart httpd 
[root@server ssh]# systemctl status httpd 
● httpd.service - The Apache HTTP Server
     Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; preset: disabled)
     Active: active (running) since Mon 2024-09-30 10:48:23 +0545; 19s ago
       Docs: man:httpd.service(8)
   Main PID: 5673 (httpd)
     Status: "Total requests: 0; Idle/Busy workers 100/0;Requests/sec: 0; Bytes served/sec:   0 B/sec"
      Tasks: 177 (limit: 22585)
     Memory: 25.2M
        CPU: 173ms
     CGroup: /system.slice/httpd.service
             ├─5673 /usr/sbin/httpd -DFOREGROUND
             ├─5686 /usr/sbin/httpd -DFOREGROUND
             ├─5687 /usr/sbin/httpd -DFOREGROUND
             ├─5691 /usr/sbin/httpd -DFOREGROUND
             └─5692 /usr/sbin/httpd -DFOREGROUND
 
Sep 30 10:47:27 server systemd[1]: Starting The Apache HTTP Server...
Sep 30 10:47:55 server httpd[5673]: AH00558: httpd: Could not reliably determine the server's fully quali>
Sep 30 10:48:23 server httpd[5673]: Server configured, listening on: port 8098
Sep 30 10:48:23 server systemd[1]: Started The Apache HTTP Server.'
 
 
# Allow the port permanently in firewall 
[root@server ssh]# firewall-cmd --permanent --add-port=8098/tcp
success
[root@server ssh]# firewall-cmd --reload 
success
[root@server ssh]# firewall-cmd --list-all
public (active)
  target: default
  icmp-block-inversion: no
  interfaces: ens160
  sources: 
  services: cockpit dhcpv6-client http mountd nfs rpc-bind ssh
  ports: 8098/tcp
  protocols: 
  forward: yes
  masquerade: no
  forward-ports: 
  source-ports: 
  icmp-blocks: 
  rich rules: 
 

[root@server ssh]# semanage port -d -t http_port_t -p tcp 8098