T5261: Add AWS load-balancing tunnel handler

Add AWS load-balancing tunnel handler
https://aws.amazon.com/blogs/networking-and-content-delivery/how-to-integrate-linux-instances-with-aws-gateway-load-balancer/

set service aws glb script on-create '/config/scripts/tmp.sh'
set service aws glb script on-destroy '/config/scripts/tmp.sh'
set service aws glb status format 'simple'
set service aws glb status port '8282'
set service aws glb threads tunnel '4'
set service aws glb threads tunnel-affinity '1-2'
set service aws glb threads udp '4'
set service aws glb threads udp-affinity '0-3'

1 files changed, 76 insertions, 0 deletions

diff --git a/src/conf_mode/service_aws_glb.py b/src/conf_mode/service_aws_glb.py
new file mode 100755
index 000000000..d1ed5a07b
--- /dev/null
+++ b/src/conf_mode/service_aws_glb.py
@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2023 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from sys import exit
+
+from vyos.config import Config
+from vyos.template import render
+from vyos.utils.process import call
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+systemd_service = 'aws-gwlbtun.service'
+systemd_override = '/run/systemd/system/aws-gwlbtun.service.d/10-override.conf'
+
+
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+    base = ['service', 'aws', 'glb']
+    if not conf.exists(base):
+        return None
+
+    glb = conf.get_config_dict(base, key_mangling=('-', '_'),
+                                      get_first_key=True,
+                                      no_tag_node_value_mangle=True)
+
+    return glb
+
+
+def verify(glb):
+    # bail out early - looks like removal from running config
+    if not glb:
+        return None
+
+
+def generate(glb):
+    if not glb:
+         return None
+
+    render(systemd_override, 'aws/override_aws_gwlbtun.conf.j2', glb)
+
+
+def apply(glb):
+    call('systemctl daemon-reload')
+    if not glb:
+        call(f'systemctl stop {systemd_service}')
+    else:
+        call(f'systemctl restart {systemd_service}')
+    return None
+
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)