New Rule: networkmanager_dns_mode

components/networkmanager.yml

@@ -0,0 +1,5 @@
+name: NetworkManager
+packages:
+- NetworkManager
+rules:
+- networkmanager_dns_mode

controls/srg_gpos/SRG-OS-000480-GPOS-00227.yml

@@ -225,6 +225,10 @@ controls:
             - set_firewalld_default_zone
             - firewalld_sshd_port_enabled
 
+            # NetworkManger
+            - networkmanager_dns_mode
+            - var_networkmanager_dns_mode=none
+
             # misc
             - enable_authselect
             - no_host_based_files

linux_os/guide/system/network/networkmanager/group.yml

@@ -0,0 +1,7 @@
+documentation_complete: true
+
+title: 'Network Manager'
+
+description: |-
+    The NetworkManager daemon configures a variety of network connections.
+    This section discusses how to configure NetworkManager.

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/ansible/shared.yml

@@ -0,0 +1,14 @@
+# platform = multi_platform_all
+# reboot = false
+# strategy = configure
+# complexity = low
+# disruption = low
+
+{{{ ansible_instantiate_variables("var_networkmanager_dns_mode") }}}
+
+{{{ ansible_ini_file_set("/etc/NetworkManager/NetworkManager.conf", "main", "dns", "{{ var_networkmanager_dns_mode }}") }}}
+
+- name: "{{{ rule_title }}} - Ensure Network Manager"
+  ansible.builtin.systemd:
+      name: NetworkManager
+      state: reloaded

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/bash/shared.sh

@@ -0,0 +1,11 @@
+# platform = multi_platform_all
+# reboot = false
+# strategy = configure
+# complexity = low
+# disruption = medium
+
+{{{ bash_instantiate_variables("var_networkmanager_dns_mode") }}}
+
+{{{ bash_ini_file_set("/etc/NetworkManager/NetworkManager.conf", "main", "dns", "$var_networkmanager_dns_mode") }}}
+
+systemctl reload NetworkManager

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/oval/shared.xml

@@ -0,0 +1,12 @@
+{{{
+oval_check_ini_file(
+    path="/etc/NetworkManager/NetworkManager.conf",
+    section="main",
+    parameter="dns",
+    value="default|none",
+    missing_parameter_pass=false,
+    application="NetworkManager",
+    multi_value=false,
+    missing_config_file_fail=true
+)
+}}}

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/policy/stig/shared.yml

@@ -0,0 +1,15 @@
+checktext: |-
+    [main]
+    dns=none
+
+    If the dns key under main does not exist or is not set to "none" or "default", this is a finding.
+
+fixtext: |-
+    Configure NetworkManager in RHEL 9 to use a DNS mode.
+
+    In "/etc/NetworkManager/NetworkManager.conf" add the following line in the "[main]" section:
+
+    dns = none
+
+srg_requirement: |-
+    {{ full_name }} must configure a DNS processing mode set be Network Manager.

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/rule.yml

@@ -0,0 +1,34 @@
+documentation_complete: true
+
+prodtype: rhel9
+
+title: 'NetworkManager DNS Mode Must Be Must Configured'
+
+description:
+    The DNS processing mode in NetworkManager describes how DNS is processed on the system.
+    Depending the mode some changes the system's DNS may not be respected.
+
+rationale:
+    To ensure that DNS resolver settings are respected, a DNS mode in NetworkManager must be configured.
+
+severity: medium
+
+identifiers:
+    cce@rhel9: CCE-86805-9
+
+references:
+    disa: CCI-000366
+    nist: CM-6(b)
+    srg: SRG-OS-000480-GPOS-00227
+
+ocil_clause: 'the dns key under main does not exist or is not set to "none" or "default"'
+
+
+ocil: |-
+    Verify that {{{ full_name }}} has a DNS mode configured in Network Manager.
+
+    $ NetworkManager --print-config
+    [main]
+    dns={{{ xccdf_value("var_networkmanager_dns_mode") }}}
+
+platform: package[NetworkManager]

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/tests/correct.pass.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+# variables = var_networkmanager_dns_mode = none
+# packages = NetworkManager
+
+cat > /etc/NetworkManager/NetworkManager.conf << EOM
+[main]
+dns=none
+EOM

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/tests/correct_default.pass.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+# variables = var_networkmanager_dns_mode = default
+# packages = NetworkManager
+
+cat > /etc/NetworkManager/NetworkManager.conf << EOM
+[main]
+dns=default
+EOM

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/tests/missing.fail.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+# variables = var_networkmanager_dns_mode = default
+
+sed '/^dns=.*$/d' /etc/NetworkManager/NetworkManager.conf

linux_os/guide/system/network/networkmanager/networkmanager_dns_mode/tests/wrong_value.fail.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+# variables = var_networkmanager_dns_mode = default
+# packages = NetworkManager
+
+cat > /etc/NetworkManager/NetworkManager.conf << EOM
+[main]
+dns=dnsmasq
+EOM

linux_os/guide/system/network/networkmanager/var_networkmanager_dns_mode.var

@@ -0,0 +1,19 @@
+documentation_complete: true
+
+title: 'NetoworkManager DNS Mode'
+
+type: string
+
+description: |-
+    This sets how NetworkManager handles DNS.
+
+    none -  NetworkManager will not modify resolv.conf.
+    default - NetworkManager will update /etc/resolv.conf to reflect the nameservers provided by currently active connections.
+
+interactive: true
+
+operator: 'equals'
+
+options:
+    none: none
+    default: default

shared/applicability/package.yml

@@ -97,3 +97,5 @@ args:
     pkgname: zypper
   openssh:
     pkgname: openssh
+  networkmanager:
+    pkgname: NetworkManager

shared/references/cce-redhat-avail.txt

@@ -452,7 +452,6 @@ CCE-86799-4
 CCE-86802-6
 CCE-86803-4
 CCE-86804-2
-CCE-86805-9
 CCE-86806-7
 CCE-86807-5
 CCE-86808-3