srv6: T591: initial implementation to support locator definition

VyOS CLI

set protocols segment-routing srv6 locator bar prefix '2001:b::/64'
set protocols segment-routing srv6 locator foo behavior-usid
set protocols segment-routing srv6 locator foo prefix '2001:a::/64'

Will generate in FRR

segment-routing
 srv6
  locators
   locator bar
    prefix 2001:b::/64 block-len 40 node-len 24 func-bits 16
   exit
   !
   locator foo
    prefix 2001:a::/64 block-len 40 node-len 24 func-bits 16
    behavior usid
   exit
   !
  exit
  !
 exit
 !
exit

1 files changed, 74 insertions, 0 deletions

diff --git a/src/conf_mode/protocols_segment_routing.py b/src/conf_mode/protocols_segment_routing.py
new file mode 100755
index 000000000..eb1653212
--- /dev/null
+++ b/src/conf_mode/protocols_segment_routing.py
@@ -0,0 +1,74 @@
+#!/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/>.
+
+import os
+
+from sys import exit
+
+from vyos.config import Config
+from vyos.template import render_to_string
+from vyos import ConfigError
+from vyos import frr
+from vyos import airbag
+airbag.enable()
+
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+
+    base = ['protocols', 'segment-routing']
+    sr = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True, no_tag_node_value_mangle=True)
+
+    # We have gathered the dict representation of the CLI, but there are default
+    # options which we need to update into the dictionary retrived.
+    sr = conf.merge_defaults(sr, recursive=True)
+
+    return sr
+
+def verify(static):
+    return None
+
+def generate(static):
+    if not static:
+        return None
+
+    static['new_frr_config'] = render_to_string('frr/zebra.segment_routing.frr.j2', static)
+    return None
+
+def apply(static):
+    zebra_daemon = 'zebra'
+
+    # Save original configuration prior to starting any commit actions
+    frr_cfg = frr.FRRConfig()
+    frr_cfg.load_configuration(zebra_daemon)
+    frr_cfg.modify_section(r'^segment-routing')
+    if 'new_frr_config' in static:
+        frr_cfg.add_before(frr.default_add_before, static['new_frr_config'])
+    frr_cfg.commit_configuration(zebra_daemon)
+
+    return None
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)