op_mode: T6181: A feature for checking ports (backport #4038)

Makefile

@@ -62,6 +62,7 @@ op_mode_definitions: $(op_xml_obj)
 	ln -s ../node.tag $(OP_TMPL_DIR)/mtr/node.tag/node.tag/
 	ln -s ../node.tag $(OP_TMPL_DIR)/monitor/traceroute/node.tag/node.tag/
 	ln -s ../node.tag $(OP_TMPL_DIR)/monitor/traffic/interface/node.tag/node.tag/
+	ln -s ../node.tag $(OP_TMPL_DIR)/execute/port-scan/host/node.tag/node.tag/
 
 	# XXX: test if there are empty node.def files - this is not allowed as these
 	# could mask help strings or mandatory priority statements

op-mode-definitions/execute-port-scan.xml.in

@@ -0,0 +1,34 @@
+<?xml version="1.0"?>
+<interfaceDefinition>
+  <node name="execute">
+    <children>
+      <node name="port-scan">
+        <properties>
+          <help>Scan network for open ports</help>
+        </properties>
+        <children>
+          <tagNode name="host">
+            <properties>
+              <help>IP address or domain name of the host to scan (scan all ports 1-65535)</help>
+              <completionHelp>
+                <list>&lt;hostname&gt; &lt;x.x.x.x&gt; &lt;h:h:h:h:h:h:h:h&gt;</list>
+              </completionHelp>
+            </properties>
+            <command>nmap -p- -T4 --max-retries=1 --host-timeout=30s "$4"</command>
+            <children>
+              <leafNode name="node.tag">
+                <properties>
+                  <help>Port scan options</help>
+                  <completionHelp>
+                    <script>${vyos_op_scripts_dir}/execute_port-scan.py --get-options-nested "${COMP_WORDS[@]}"</script>
+                  </completionHelp>
+                </properties>
+                <command>${vyos_op_scripts_dir}/execute_port-scan.py "${@:4}"</command>
+              </leafNode>
+            </children>
+          </tagNode>
+        </children>
+      </node>
+    </children>
+  </node>
+</interfaceDefinition>

src/op_mode/execute_port-scan.py

@@ -0,0 +1,155 @@
+#! /usr/bin/env python3
+#
+# Copyright (C) 2024 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 sys
+
+from vyos.utils.process import call
+
+
+options = {
+    'port': {
+        'cmd': '{command} -p {value}',
+        'type': '<1-65535> <list>',
+        'help': 'Scan specified ports.'
+    },
+    'tcp': {
+        'cmd': '{command} -sT',
+        'type': 'noarg',
+        'help': 'Use TCP scan.'
+    },
+    'udp': {
+        'cmd': '{command} -sU',
+        'type': 'noarg',
+        'help': 'Use UDP scan.'
+    },
+    'skip-ping': {
+        'cmd': '{command} -Pn',
+        'type': 'noarg',
+        'help': 'Skip the Nmap discovery stage altogether.'
+    },
+    'ipv6': {
+        'cmd': '{command} -6',
+        'type': 'noarg',
+        'help': 'Enable IPv6 scanning.'
+    },
+}
+
+nmap = 'sudo /usr/bin/nmap'
+
+
+class List(list):
+    def first(self):
+        return self.pop(0) if self else ''
+
+    def last(self):
+        return self.pop() if self else ''
+
+    def prepend(self, value):
+        self.insert(0, value)
+
+
+def completion_failure(option: str) -> None:
+    """
+    Shows failure message after TAB when option is wrong
+    :param option: failure option
+    :type str:
+    """
+    sys.stderr.write('\n\n Invalid option: {}\n\n'.format(option))
+    sys.stdout.write('<nocomps>')
+    sys.exit(1)
+
+
+def expansion_failure(option, completions):
+    reason = 'Ambiguous' if completions else 'Invalid'
+    sys.stderr.write(
+        '\n\n  {} command: {} [{}]\n\n'.format(reason, ' '.join(sys.argv),
+                                               option))
+    if completions:
+        sys.stderr.write('  Possible completions:\n   ')
+        sys.stderr.write('\n   '.join(completions))
+        sys.stderr.write('\n')
+    sys.stdout.write('<nocomps>')
+    sys.exit(1)
+
+
+def complete(prefix):
+    return [o for o in options if o.startswith(prefix)]
+
+
+def convert(command, args):
+    while args:
+        shortname = args.first()
+        longnames = complete(shortname)
+        if len(longnames) != 1:
+            expansion_failure(shortname, longnames)
+        longname = longnames[0]
+        if options[longname]['type'] == 'noarg':
+            command = options[longname]['cmd'].format(
+                command=command, value='')
+        elif not args:
+            sys.exit(f'port-scan: missing argument for {longname} option')
+        else:
+            command = options[longname]['cmd'].format(
+                command=command, value=args.first())
+    return command
+
+
+if __name__ == '__main__':
+    args = List(sys.argv[1:])
+    host = args.first()
+
+    if host == '--get-options-nested':
+        args.first()  # pop execute
+        args.first()  # pop port-scan
+        args.first()  # pop host
+        args.first()  # pop <host>
+        usedoptionslist = []
+        while args:
+            option = args.first()  # pop option
+            matched = complete(option)  # get option parameters
+            usedoptionslist.append(option)  # list of used options
+            # Select options
+            if not args:
+                # remove from Possible completions used options
+                for o in usedoptionslist:
+                    if o in matched:
+                        matched.remove(o)
+                if not matched:
+                    sys.stdout.write('<nocomps>')
+                else:
+                    sys.stdout.write(' '.join(matched))
+                sys.exit(0)
+
+            if len(matched) > 1:
+                sys.stdout.write(' '.join(matched))
+                sys.exit(0)
+            # If option doesn't have value
+            if matched:
+                if options[matched[0]]['type'] == 'noarg':
+                    continue
+            else:
+                # Unexpected option
+                completion_failure(option)
+
+            value = args.first()  # pop option's value
+            if not args:
+                matched = complete(option)
+                helplines = options[matched[0]]['type']
+                sys.stdout.write(helplines)
+                sys.exit(0)
+
+    command = convert(nmap, args)
+    call(f'{command} -T4 {host}')