Warning message before interactive login

This patch adds interactive login message to all installations
that include system/linux/system/single.

Related-Prod: PROD-19166
Related-Prod: PROD-18882

Change-Id: Ib7e9e5f1684a46cdc250214f2f640b09255d34f6
diff --git a/linux/system/banner.yml b/linux/system/banner.yml
new file mode 100644
index 0000000..173a044
--- /dev/null
+++ b/linux/system/banner.yml
@@ -0,0 +1,17 @@
+parameters:
+  _param:
+    banner_company_name: COMPANY_NAME_HERE
+  linux:
+    system:
+      banner:
+        enabled: true
+        contents: |
+          =================================== WARNING ====================================
+          You have accessed a computer managed by ${_param:banner_company_name}.
+          You are required to have authorisation from ${_param:banner_company_name}
+          before you proceed and you are strictly limited to use set out within that
+          authorisation. Unauthorised access to or misuse of this system is prohibited
+          and constitutes an offence under the Computer Misuse Act 1990.
+          If you disclose any information obtained through this system without authority
+          ${_param:banner_company_name} may take legal action against you.
+          ================================================================================
diff --git a/linux/system/single/init.yml b/linux/system/single/init.yml
index dae70ff..4429a82 100644
--- a/linux/system/single/init.yml
+++ b/linux/system/single/init.yml
@@ -1,6 +1,7 @@
 classes:
 - service.linux.system
 - service.salt.minion.master
+- system.linux.system.banner
 - system.openssh.server.single
 - system.ntp.client.single
 parameters: