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NCAE minihack CentOS

Misc. Things

  • May want to learn GNU nano in case vi / vim is ever unavailable.
  • Learn enhanced curl commands
  • In this case we're using firewalld. What are the other common firewall services used in linux/unix environments?
  • DNS

Notes

  • Config network settings for each VM
    • Kali external/internal + CentOS Router + Ubuntu internal server
    • interfaces / IPs + individual misc. settings per host
  • VM Hosts
    • CentOS Router
      • Steps:
        • Network Configs (/etc/sysconfig/network-scripts/) ← location of ifcfg files
          • external interface
            • BOOTPROTO=static (no dhcp server)
            • ONBOOT=yes
            • Set IP address. This will become the internal network's default gateway
              • IPADDR=external network ip
              • NETMASK=255.255.0.0
            • ZONE=external
            • firewall-cmd
              • port forwarding
          • internal interface
            • BOOTPROTO=static (no dhcp server)
            • ONBOOT=yes
            • Set IP address. This will become the internal network's default gateway
              • IPADDR=internal network ip (default gateway)
              • NETMASK=255.255.255.0
            • ZONE=internal
            • masquerading
      • ifcfg files for configuration of network interfaces
      • firewall-cmd
    • Ubuntu w/ Apache webserver (ubuntu host)
      • Steps:
        • Network Configs defined in netplan YAML file (/etc/netplan/01-network-manager-all.yaml)
          • ethernets:
            • ens18:
              • addresses:
                • - 192.x.x.x/24
              • gateway4: 192.x.x.x/24
          • sudo netplan apply
        • change index.html content to team number
        • enable and start the apache2 web service
      • uses Netplan for network settings (ubuntu)
      • configure its default gateway using the router address
        • This will cause the internal ubuntu server to send outbound traffic to the default gateway/router when traffic sent does not have an existing valid recipient on the current network segment
        • Masquerading (enabled on the router's internal zone) then allows this traffic to be directed to outside networks (this is a type of NAT)
    • Kali External
      • Steps
        • network config in /etc/network/interfaces
          • static interface (iface eth0 inet static)
          • set IP (address)
          • set subnet mask (netmask)
          • DOES NOT need a default gateway. There is no other router for it to use
    • Kali Internal (not needed for scoring of initial minihack challenge itself)
      • Steps
        • network config in /etc/network/interfaces
          • static interface (iface eth0 inet static)
          • set IP (address)
          • set subnet mask (netmask)
          • set default gateway (gateway)