T623: refactor NTP script and switch to jinja2

1 files changed, 93 insertions, 60 deletions

diff --git a/src/conf-mode/vyos-config-ntp.py b/src/conf-mode/vyos-config-ntp.py
index b9328f3e0..061e8760e 100755
--- a/src/conf-mode/vyos-config-ntp.py
+++ b/src/conf-mode/vyos-config-ntp.py
@@ -18,7 +18,8 @@
 
 import sys
 import os
-import time
+
+import jinja2
 import ipaddress
 
 from vyos.config import Config
@@ -26,95 +27,127 @@ from vyos.util import ConfigError
 
 config_file = r'/etc/ntp.conf'
 
+# Please be careful if you edit the template.
+config_tmpl = """
+### Autogenerated by vyos-config-ntp.py ###
+
+#
+# Non-configurable defaults
+#
+driftfile /var/lib/ntp/ntp.drift
+# By default, only allow ntpd to query time sources, ignore any incoming requests
+restrict default ignore
+# Local users have unrestricted access, allowing reconfiguration via ntpdc
+restrict 127.0.0.1
+restrict -6 ::1
+
+
+#
+# Configurable section
+#
+
+{% if servers -%}
+{% for s in servers -%}
+# Server configuration for: {{ s.name }}
+server {{ s.name }} iburst {{ s.options | join(" ") }}
+
+{% endfor -%}
+{% endif %}
+
+{% if allowed_networks -%}
+{% for n in allowed_networks -%}
+# Client configuration for network: {{ n.network }}
+restrict {{ n.address }} mask {{ n.netmask }} nomodify notrap nopeer
+
+{% endfor -%}
+{% endif %}
+
+"""
+
+default_config_data = {
+    'servers': [],
+    'allowed_networks': []
+}
+
 def get_config():
-    ntp = {}
+    ntp = default_config_data
     conf = Config()
-    conf.set_level('system ntp')
-    if not conf.exists(''):
-        return ntp
+    if not conf.exists('system ntp'):
+        return None
+    else:
+        conf.set_level('system ntp')
 
     if conf.exists('allow-clients address'):
-        ntp.setdefault('allow-networks', [])
-        networks = []
         networks = conf.return_values('allow-clients address')
-        for network in networks:
-            ntp['allow-networks'].append(network)
+        for n in networks:
+            addr = ipaddress.ip_network(n)
+            net = {
+                "network" : n,
+                "address" : addr.network_address,
+                "netmask" : addr.netmask
+            }
+
+            ntp['allowed_networks'].append(net)
 
     if conf.exists('server'):
-        ntp.setdefault('servers', [])
         for node in conf.list_nodes('server'):
+            options = []
             server = {
                 "name": node,
-                "dynamic": False,
-                "noselect": False,
-                "preempt": False,
-                "prefer": False,
+                "options": []
             }
             if conf.exists('server {0} dynamic'.format(node)):
-                server['dynamic'] = True
+                options.append('dynamic')
             if conf.exists('server {0} noselect'.format(node)):
-                server['noselect'] = True
+                options.append('noselect')
             if conf.exists('server {0} preempt'.format(node)):
-                server['preempt'] = True
+                options.append('preempt')
             if conf.exists('server {0} prefer'.format(node)):
-                server['prefer'] = True
+                options.append('prefer')
 
+            server['options'] = options
             ntp['servers'].append(server)
 
     return ntp
 
 def verify(ntp):
-    if 'allow-networks' in ntp.keys():
-        for network in ntp['allow-networks']:
-            try:
-                addr = ipaddress.ip_network(network)
-            except ValueError:
-                raise ConfigError("{0} does not appear to be a valid IPv4 or IPv6 network, check host bits.".format(network))
+    # bail out early - looks like removal from running config
+    if ntp is None:
+        return None
+
+    # Configuring allowed clients without a server makes no sense
+    if len(ntp['allowed_networks']) and not len(ntp['servers']):
+        raise ConfigError('NTP server not configured')
+
+    for n in ntp['allowed_networks']:
+        try:
+            addr = ipaddress.ip_network( n['network'] )
+            break
+        except ValueError:
+            raise ConfigError("{0} does not appear to be a valid IPv4 or IPv6 network, check host bits!".format(n['network']))
 
     return None
 
 def generate(ntp):
-    config_header = '### Autogenerated by vyos-config-ntp.py on {tm} ###\n'.format(tm=time.strftime("%a, %d %b %Y %H:%M:%S", time.localtime()))
-
-    # write new configuration file
-    f = open(config_file, 'w')
-    f.write(config_header)
-    f.write('\n')
-    f.write('driftfile /var/lib/ntp/ntp.drift\n')
-    f.write('\n')
-    f.write('# By default, only allow ntpd to query time sources, ignore any incoming requests\n')
-    f.write('restrict default ignore\n')
-    f.write('\n')
-    f.write('# Local users have unrestricted access, allowing reconfiguration via ntpdc\n')
-    f.write('restrict 127.0.0.1\n')
-    f.write('restrict -6 ::1\n')
-    f.write('\n')
-
-    if 'servers' in ntp.keys():
-        for server in ntp['servers']:
-            opt = ['dynamic', 'noselect', 'preempt', 'prefer']
-            f.write('# Server configuration for: {0}\n'.format(server['name']))
-            f.write('server {0} iburst {1}\n'.format(server['name'], '{0}'.format(' '.join(str(o) for o in opt if server[o]))))
-            f.write('restrict {0} nomodify notrap nopeer noquery\n'.format(server['name']))
-            f.write('\n')
-
-    if 'allow-networks' in ntp.keys():
-        for network in ntp['allow-networks']:
-            addr = ipaddress.ip_network(network)
-            f.write('# Client configuration for network: {0}\n'.format(network))
-            f.write('restrict {0} mask {1} nomodify notrap nopeer\n'.format(addr.network_address, addr.netmask))
-            f.write('\n')
-
-    f.close()
+    # bail out early - looks like removal from running config
+    if ntp is None:
+        return None
+
+    tmpl = jinja2.Template(config_tmpl)
+    config_text = tmpl.render(ntp)
+    with open(config_file, 'w') as f:
+        f.write(config_text)
+
     return None
 
 def apply(ntp):
-    if len(ntp) == 0:
-        cmd = "sudo /usr/sbin/invoke-rc.d ntp stop"
+    if ntp is not None:
+        os.system('sudo /usr/sbin/invoke-rc.d ntp force-reload')
     else:
-        cmd = "sudo /usr/sbin/invoke-rc.d ntp force-reload"
+        # NTP suuport is removed in the commit
+        os.system('sudo /usr/sbin/invoke-rc.d ntp stop')
+        os.unlink(config_file)
 
-    os.system(cmd)
     return None
 
 if __name__ == '__main__':