[Banner] Add new feature including config, yang and tests

files/build_templates/init_cfg.json.j2

@@ -144,6 +144,14 @@
             "special_class": "true"
         }
     },
+    "BANNER_MESSAGE": {
+        "global": {
+            "state": "disabled",
+            "login": "Debian GNU/Linux 11",
+            "motd": "You are on\n  ____   ___  _   _ _  ____\n / ___| / _ \\| \\ | (_)/ ___|\n \\___ \\| | | |  \\| | | |\n  ___) | |_| | |\\  | | |___\n |____/ \\___/|_| \\_|_|\\____|\n\n-- Software for Open Networking in the Cloud --\n\nUnauthorized access and/or use are prohibited.\nAll access and/or use are subject to monitoring.\n\nHelp:    https://sonic-net.github.io/SONiC/\n\n",
+            "logout": ""
+        }
+    },
     "SYSTEM_DEFAULTS" : {
 {%- if include_mux == "y" %}
         "mux_tunnel_egress_acl": {

files/build_templates/sonic_debian_extension.j2

@@ -86,6 +86,7 @@ sudo LANG=C DEBIAN_FRONTEND=noninteractive chroot $FILESYSTEM_ROOT apt-get -y in
 # Apply environtment configuration files
 sudo cp $IMAGE_CONFIGS/environment/environment $FILESYSTEM_ROOT/etc/
 sudo cp $IMAGE_CONFIGS/environment/motd $FILESYSTEM_ROOT/etc/
+sudo cp $IMAGE_CONFIGS/environment/logout_message $FILESYSTEM_ROOT/etc/
 
 # Create all needed directories
 sudo mkdir -p $FILESYSTEM_ROOT/etc/sonic/
@@ -223,6 +224,7 @@ sudo dpkg --root=$FILESYSTEM_ROOT -i $debs_path/bash_*.deb || \
 # sonic-utilities-data installs bash-completion as a dependency. However, it is disabled by default
 # in bash.bashrc, so we copy a version of the file with it enabled here.
 sudo cp -f $IMAGE_CONFIGS/bash/bash.bashrc $FILESYSTEM_ROOT/etc/
+sudo cp -f $IMAGE_CONFIGS/bash/bash.bash_logout $FILESYSTEM_ROOT/etc/
 
 # Install readline's initialization file
 sudo cp -f $IMAGE_CONFIGS/readline/inputrc $FILESYSTEM_ROOT/etc/
@@ -589,6 +591,11 @@ sudo cp $IMAGE_CONFIGS/hostname/hostname-config.service $FILESYSTEM_ROOT_USR_LIB
 echo "hostname-config.service" | sudo tee -a $GENERATED_SERVICE_FILE
 sudo cp $IMAGE_CONFIGS/hostname/hostname-config.sh $FILESYSTEM_ROOT/usr/bin/
 
+# Copy banner configuration scripts
+sudo cp $IMAGE_CONFIGS/bannerconfig/banner-config.service $FILESYSTEM_ROOT_USR_LIB_SYSTEMD_SYSTEM
+echo "banner-config.service" | sudo tee -a $GENERATED_SERVICE_FILE
+sudo cp $IMAGE_CONFIGS/bannerconfig/banner-config.sh $FILESYSTEM_ROOT/usr/bin/
+
 # Copy miscellaneous scripts
 sudo cp $IMAGE_CONFIGS/misc/docker-wait-any $FILESYSTEM_ROOT/usr/bin/
 

files/image_config/bannerconfig/banner-config.service

@@ -0,0 +1,17 @@
+[Unit]
+Description=Update banner config based on configdb
+Requires=config-setup.service
+After=config-setup.service
+Before=systemd-logind.service sshd.service
+BindsTo=database.service
+BindsTo=sonic.target
+
+[Service]
+Type=oneshot
+RemainAfterExit=no
+ExecStart=/usr/bin/banner-config.sh
+
+[Install]
+WantedBy=sonic.target
+
+

files/image_config/bannerconfig/banner-config.sh

@@ -0,0 +1,17 @@
+#!/bin/bash -e
+
+STATE=$(sonic-cfggen -d -v 'BANNER_MESSAGE["global"]["state"]')
+LOGIN=
+MOTD=
+LOGOUT=
+
+if [[ $STATE == "enabled" ]]; then
+    LOGIN=$(sonic-cfggen -d -v 'BANNER_MESSAGE["global"]["login"]')
+    MOTD=$(sonic-cfggen -d -v 'BANNER_MESSAGE["global"]["motd"]')
+    LOGOUT=$(sonic-cfggen -d -v 'BANNER_MESSAGE["global"]["logout"]')
+
+    echo -e "$LOGIN" > /etc/issue.net
+    echo -e "$LOGIN" > /etc/issue
+    echo -e "$MOTD" > /etc/motd
+    echo -e "$LOGOUT" > /etc/logout_message
+fi

files/image_config/bash/bash.bash_logout

@@ -0,0 +1,12 @@
+LOGOUT_MESSAGE_PATH="/etc/logout_message"
+LOGOUT_MESSAGE=
+
+if [[ -f "$LOGOUT_MESSAGE_PATH" ]]; then
+    LOGOUT_MESSAGE=$(cat $LOGOUT_MESSAGE_PATH)
+fi
+
+if [[ -n "$LOGOUT_MESSAGE" ]]; then
+    # Print logout message
+    echo $LOGOUT_MESSAGE
+fi
+

src/sonic-yang-models/setup.py

@@ -86,6 +86,7 @@ def run(self):
         ('yang-models', ['./yang-models/sonic-acl.yang',
                          './yang-models/sonic-auto_techsupport.yang',
                          './yang-models/sonic-bgp-bbr.yang',
+                         './yang-models/sonic-banner.yang',
                          './yang-models/sonic-bgp-common.yang',
                          './yang-models/sonic-bgp-device-global.yang',
                          './yang-models/sonic-bgp-global.yang',
@@ -201,6 +202,7 @@ def run(self):
                          './yang-models/sonic-bgp-sentinel.yang',
                          './yang-models/sonic-smart-switch.yang',]),
         ('cvlyang-models', ['./cvlyang-models/sonic-acl.yang',
+                         './cvlyang-models/sonic-banner.yang',
                          './cvlyang-models/sonic-bgp-common.yang',
                          './cvlyang-models/sonic-bgp-global.yang',
                          './cvlyang-models/sonic-bgp-monitor.yang',

src/sonic-yang-models/tests/files/sample_config_db.json

@@ -2623,6 +2623,14 @@
             "dpu1": {
                 "midplane_interface": "dpu1"
             }
+        },
+        "BANNER_MESSAGE": {
+            "global": {
+                "state": "enabled",
+                "login": "Some login message",
+                "motd": "Some message of the day",
+                "logout": "Some logout message"
+            }
         }
     },
     "SAMPLE_CONFIG_DB_UNKNOWN": {

src/sonic-yang-models/tests/yang_model_tests/tests/sonic-banner.json

@@ -0,0 +1,14 @@
+{
+    "BANNER_MESSAGE_TEST_STATE": {
+        "desc": "Configure Banner feature state."
+    },
+    "BANNER_MESSAGE_TEST_LOGIN" : {
+        "desc": "Banner login messages configuration in BANNER_MESSAGE table."
+    },
+    "BANNER_MESSAGE_TEST_MOTD" : {
+        "desc": "Banner MOTD messages configuration in BANNER_MESSAGE table."
+    },
+    "BANNER_MESSAGE_TEST_LOGOUT" : {
+        "desc": "Banner logout messages configuration in BANNER_MESSAGE table."
+    }
+}

src/sonic-yang-models/tests/yang_model_tests/tests_config/sonic-banner.json

@@ -0,0 +1,50 @@
+{
+    "BANNER_MESSAGE_TEST_STATE": {
+        "sonic-banner:sonic-banner": {
+            "sonic-banner:BANNER_MESSAGE": {
+                "global": {
+                    "state": "enabled",
+                    "login": "Some login message",
+                    "motd": "Some message of the day",
+                    "logout": "Some logout message"
+                }
+            }
+        }
+    },
+    "BANNER_MESSAGE_TEST_LOGIN": {
+        "sonic-banner:sonic-banner": {
+            "sonic-banner:BANNER_MESSAGE": {
+                "global": {
+                    "state": "enabled",
+                    "login": "Some login message",
+                    "motd": "Some message of the day",
+                    "logout": "Some logout message"
+                }
+            }
+        }
+    },
+    "BANNER_MESSAGE_TEST_MOTD": {
+        "sonic-banner:sonic-banner": {
+            "sonic-banner:BANNER_MESSAGE": {
+                "global": {
+                    "state": "enabled",
+                    "login": "Some login message",
+                    "motd": "Some message of the day",
+                    "logout": "Some logout message"
+                }
+            }
+        }
+    },
+    "BANNER_MESSAGE_TEST_LOGOUT": {
+        "sonic-banner:sonic-banner": {
+            "sonic-banner:BANNER_MESSAGE": {
+                "global": {
+                    "state": "enabled",
+                    "login": "Some login message",
+                    "motd": "Some message of the day",
+                    "logout": "Some logout message"
+                }
+            }
+        }
+    }
+}

src/sonic-yang-models/yang-models/sonic-banner.yang

@@ -0,0 +1,51 @@
+module sonic-banner {
+    yang-version 1.1;
+    namespace "http://github.com/sonic-net/sonic-banner";
+    prefix banner_message;
+
+    import sonic-types {
+        prefix stypes;
+    }
+
+    description "BANNER_MESSAGE YANG Module for SONiC-based OS";
+    revision 2023-05-18 {
+        description "First Revision";
+    }
+    container sonic-banner {
+        container BANNER_MESSAGE {
+            description "BANNER_MESSAGE part of config_db.json";
+            container global {
+                leaf state {
+                    type stypes:admin_mode;
+                    description "Banner feature state";
+                    default disabled;
+                }
+                leaf login {
+                    type string;
+                    description "Banner message displayed to user before login prompt";
+                    default "Debian GNU/Linux 11";
+                }
+                leaf motd {
+                    type string;
+                    description "Banner message displayed to user after login prompt";
+                    default "You are on
+                              ____   ___  _   _ _  ____
+                             / ___| / _ \\| \\ | (_)/ ___|
+                             \\___ \\| | | |  \\| | | |
+                              ___) | |_| | |\\  | | |___
+                             |____/ \\___/|_| \\_|_|\\____|
+                             -- Software for Open Networking in the Cloud --
+                             Unauthorized access and/or use are prohibited.
+                             All access and/or use are subject to monitoring.
+                             Help:    https://sonic-net.github.io/SONiC/
+                             ";
+                }
+                leaf logout {
+                    type string;
+                    description "Banner message dispalyed to the users on logout";
+                    default "";
+                }
+            } /* end of container MESSAGE */
+        } /* end of container BANNER_MESSAGE */
+    } /* end of top level container */
+}