Merge pull request #771 from jack9603301/T2518

nat: nat66: T2518: Support operation mode command

1 files changed, 74 insertions, 0 deletions

diff --git a/src/op_mode/show_nat_rules.py b/src/op_mode/show_nat_rules.py
new file mode 100755
index 000000000..0ddb7ddd4
--- /dev/null
+++ b/src/op_mode/show_nat_rules.py
@@ -0,0 +1,74 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2021 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 jmespath
+import json
+
+from argparse import ArgumentParser
+from jinja2 import Template
+from sys import exit
+from vyos.util import cmd
+from vyos.util import dict_search
+
+parser = ArgumentParser()
+group = parser.add_mutually_exclusive_group()
+group.add_argument("--source", help="Show statistics for configured source NAT rules", action="store_true")
+group.add_argument("--destination", help="Show statistics for configured destination NAT rules", action="store_true")
+args = parser.parse_args()
+
+if args.source or args.destination:
+    tmp = cmd('sudo nft -j list table ip nat')
+    tmp = json.loads(tmp)
+    
+    format_nat66_rule = '%-10s %-50s %-50s %-10s'
+    print(format_nat66_rule % ("Rule", "Source" if args.source else "Destination", "Translation", "Outbound Interface" if args.source else "Inbound Interface"))
+    print(format_nat66_rule % ("----", "------" if args.source else "-----------", "-----------", "------------------" if args.source else "-----------------"))
+
+    data_json = jmespath.search('nftables[?rule].rule[?chain]', tmp)
+    for idx in range(0, len(data_json)):
+        data = data_json[idx]
+        comment = data['comment']
+        chain = data['chain']
+        if not (args.source and chain == 'POSTROUTING') or (not args.source and chain == 'PREROUTING'):
+            exit(0)
+        interface = dict_search('match.right', data['expr'][0])
+        srcdest = dict_search('match.right.prefix.addr', data['expr'][1])
+        if srcdest:
+            addr_tmp = dict_search('match.right.prefix.len', data['expr'][1])
+            if addr_tmp:
+                srcdest = srcdest + '/' + str(addr_tmp)
+        else:
+            srcdest = dict_search('match.right', data['expr'][1])
+        tran_addr = dict_search('snat.addr.prefix.addr' if args.source else 'dnat.addr.prefix.addr', data['expr'][3])
+        if tran_addr:
+            addr_tmp = dict_search('snat.addr.prefix.len' if args.source else 'dnat.addr.prefix.len', data['expr'][3])
+            if addr_tmp:
+                srcdest = srcdest + '/' + str(addr_tmp)
+        else:
+            if 'masquerade' in data['expr'][3]:
+                tran_addr = 'masquerade'
+            elif 'log' in data['expr'][3]:
+                continue
+            else:
+                tran_addr = dict_search('snat.addr' if args.source else 'dnat.addr', data['expr'][3])
+        
+        print(format_nat66_rule % (comment, srcdest, tran_addr, interface))
+    
+    exit(0)
+else:
+    parser.print_help()
+    exit(1)
+