ipsec: T2816: restore erroneous deleted file

Commit 22739144 ('ipsec: T2816: migrate "ipsec interfaces" to "interface"')
by accident deleted the vpn_ipsec.py Python handler.

Handler was restored.

1 files changed, 526 insertions, 0 deletions

diff --git a/src/conf_mode/vpn_ipsec.py b/src/conf_mode/vpn_ipsec.py
new file mode 100644
index 000000000..a359361f3
--- /dev/null
+++ b/src/conf_mode/vpn_ipsec.py
@@ -0,0 +1,526 @@
+#!/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 ipaddress
+import os
+
+from sys import exit
+from time import sleep
+from time import time
+
+from vyos.config import Config
+from vyos.configdict import leaf_node_changed
+from vyos.configverify import verify_interface_exists
+from vyos.configdict import dict_merge
+from vyos.ifconfig import Interface
+from vyos.pki import encode_public_key
+from vyos.pki import load_private_key
+from vyos.pki import wrap_certificate
+from vyos.pki import wrap_crl
+from vyos.pki import wrap_public_key
+from vyos.pki import wrap_private_key
+from vyos.template import ip_from_cidr
+from vyos.template import render
+from vyos.validate import is_ipv6_link_local
+from vyos.util import call
+from vyos.util import dict_search_args
+from vyos.util import run
+from vyos.xml import defaults
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+dhcp_wait_attempts = 2
+dhcp_wait_sleep = 1
+
+swanctl_dir    = '/etc/swanctl'
+ipsec_conf     = '/etc/ipsec.conf'
+ipsec_secrets  = '/etc/ipsec.secrets'
+charon_conf = '/etc/strongswan.d/charon.conf'
+charon_dhcp_conf = '/etc/strongswan.d/charon/dhcp.conf'
+interface_conf = '/etc/strongswan.d/interfaces_use.conf'
+swanctl_conf   = f'{swanctl_dir}/swanctl.conf'
+
+default_install_routes = 'yes'
+
+vici_socket = '/var/run/charon.vici'
+
+CERT_PATH = f'{swanctl_dir}/x509/'
+PUBKEY_PATH = f'{swanctl_dir}/pubkey/'
+KEY_PATH  = f'{swanctl_dir}/private/'
+CA_PATH   = f'{swanctl_dir}/x509ca/'
+CRL_PATH  = f'{swanctl_dir}/x509crl/'
+
+DHCP_BASE = '/var/lib/dhcp/dhclient'
+DHCP_HOOK_IFLIST = '/tmp/ipsec_dhcp_waiting'
+
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+    base = ['vpn', 'ipsec']
+    l2tp_base = ['vpn', 'l2tp', 'remote-access', 'ipsec-settings']
+    if not conf.exists(base):
+        return None
+
+    # retrieve common dictionary keys
+    ipsec = 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.
+    default_values = defaults(base)
+    # XXX: T2665: we must safely remove default values for tag nodes, those are
+    # added in a more fine grained way later on
+    del default_values['esp_group']
+    del default_values['ike_group']
+    del default_values['remote_access']
+    ipsec = dict_merge(default_values, ipsec)
+
+    if 'esp_group' in ipsec:
+        default_values = defaults(base + ['esp-group'])
+        for group in ipsec['esp_group']:
+            ipsec['esp_group'][group] = dict_merge(default_values,
+                                                   ipsec['esp_group'][group])
+    if 'ike_group' in ipsec:
+        default_values = defaults(base + ['ike-group'])
+        for group in ipsec['ike_group']:
+            ipsec['ike_group'][group] = dict_merge(default_values,
+                                                   ipsec['ike_group'][group])
+    if 'remote_access' in ipsec:
+        default_values = defaults(base + ['remote-access'])
+        for rw in ipsec['remote_access']:
+            ipsec['remote_access'][rw] = dict_merge(default_values,
+                                                    ipsec['remote_access'][rw])
+
+    ipsec['dhcp_no_address'] = {}
+    ipsec['install_routes'] = 'no' if conf.exists(base + ["options", "disable-route-autoinstall"]) else default_install_routes
+    ipsec['interface_change'] = leaf_node_changed(conf, base + ['interface'])
+    ipsec['nhrp_exists'] = conf.exists(['protocols', 'nhrp', 'tunnel'])
+    ipsec['pki'] = conf.get_config_dict(['pki'], key_mangling=('-', '_'),
+                                             get_first_key=True,
+                                             no_tag_node_value_mangle=True)
+
+    ipsec['l2tp'] = conf.get_config_dict(l2tp_base, key_mangling=('-', '_'),
+                                             get_first_key=True,
+                                             no_tag_node_value_mangle=True)
+    if ipsec['l2tp']:
+        l2tp_defaults = defaults(l2tp_base)
+        ipsec['l2tp'] = dict_merge(l2tp_defaults, ipsec['l2tp'])
+        ipsec['l2tp_outside_address'] = conf.return_value(['vpn', 'l2tp', 'remote-access', 'outside-address'])
+        ipsec['l2tp_ike_default'] = 'aes256-sha1-modp1024,3des-sha1-modp1024,3des-sha1-modp1024'
+        ipsec['l2tp_esp_default'] = 'aes256-sha1,3des-sha1'
+
+    return ipsec
+
+def get_dhcp_address(iface):
+    addresses = Interface(iface).get_addr()
+    if not addresses:
+        return None
+    for address in addresses:
+        if not is_ipv6_link_local(address):
+            return ip_from_cidr(address)
+    return None
+
+def verify_pki_x509(pki, x509_conf):
+    if not pki or 'ca' not in pki or 'certificate' not in pki:
+        raise ConfigError(f'PKI is not configured')
+
+    ca_cert_name = x509_conf['ca_certificate']
+    cert_name = x509_conf['certificate']
+
+    if not dict_search_args(pki, 'ca', ca_cert_name, 'certificate'):
+        raise ConfigError(f'Missing CA certificate on specified PKI CA certificate "{ca_cert_name}"')
+
+    if not dict_search_args(pki, 'certificate', cert_name, 'certificate'):
+        raise ConfigError(f'Missing certificate on specified PKI certificate "{cert_name}"')
+
+    if not dict_search_args(pki, 'certificate', cert_name, 'private', 'key'):
+        raise ConfigError(f'Missing private key on specified PKI certificate "{cert_name}"')
+
+    return True
+
+def verify_pki_rsa(pki, rsa_conf):
+    if not pki or 'key_pair' not in pki:
+        raise ConfigError(f'PKI is not configured')
+
+    local_key = rsa_conf['local_key']
+    remote_key = rsa_conf['remote_key']
+
+    if not dict_search_args(pki, 'key_pair', local_key, 'private', 'key'):
+        raise ConfigError(f'Missing private key on specified local-key "{local_key}"')
+
+    if not dict_search_args(pki, 'key_pair', remote_key, 'public', 'key'):
+        raise ConfigError(f'Missing public key on specified remote-key "{remote_key}"')
+
+    return True
+
+def verify(ipsec):
+    if not ipsec:
+        return None
+
+    if 'interfaces' in ipsec :
+        for ifname in ipsec['interface']:
+            verify_interface_exists(ifname)
+
+    if ipsec['l2tp']:
+        if 'esp_group' in ipsec['l2tp']:
+            if 'esp_group' not in ipsec or ipsec['l2tp']['esp_group'] not in ipsec['esp_group']:
+                raise ConfigError(f"Invalid esp-group on L2TP remote-access config")
+
+        if 'ike_group' in ipsec['l2tp']:
+            if 'ike_group' not in ipsec or ipsec['l2tp']['ike_group'] not in ipsec['ike_group']:
+                raise ConfigError(f"Invalid ike-group on L2TP remote-access config")
+
+        if 'authentication' not in ipsec['l2tp']:
+            raise ConfigError(f'Missing authentication settings on L2TP remote-access config')
+
+        if 'mode' not in ipsec['l2tp']['authentication']:
+            raise ConfigError(f'Missing authentication mode on L2TP remote-access config')
+
+        if not ipsec['l2tp_outside_address']:
+            raise ConfigError(f'Missing outside-address on L2TP remote-access config')
+
+        if ipsec['l2tp']['authentication']['mode'] == 'pre-shared-secret':
+            if 'pre_shared_secret' not in ipsec['l2tp']['authentication']:
+                raise ConfigError(f'Missing pre shared secret on L2TP remote-access config')
+
+        if ipsec['l2tp']['authentication']['mode'] == 'x509':
+            if 'x509' not in ipsec['l2tp']['authentication']:
+                raise ConfigError(f'Missing x509 settings on L2TP remote-access config')
+
+            x509 = ipsec['l2tp']['authentication']['x509']
+
+            if 'ca_certificate' not in x509 or 'certificate' not in x509:
+                raise ConfigError(f'Missing x509 certificates on L2TP remote-access config')
+
+            verify_pki_x509(ipsec['pki'], x509)
+
+    if 'profile' in ipsec:
+        for profile, profile_conf in ipsec['profile'].items():
+            if 'esp_group' in profile_conf:
+                if 'esp_group' not in ipsec or profile_conf['esp_group'] not in ipsec['esp_group']:
+                    raise ConfigError(f"Invalid esp-group on {profile} profile")
+            else:
+                raise ConfigError(f"Missing esp-group on {profile} profile")
+
+            if 'ike_group' in profile_conf:
+                if 'ike_group' not in ipsec or profile_conf['ike_group'] not in ipsec['ike_group']:
+                    raise ConfigError(f"Invalid ike-group on {profile} profile")
+            else:
+                raise ConfigError(f"Missing ike-group on {profile} profile")
+
+            if 'authentication' not in profile_conf:
+                raise ConfigError(f"Missing authentication on {profile} profile")
+
+    if 'remote_access' in ipsec:
+        for name, ra_conf in ipsec['remote_access'].items():
+            if 'esp_group' in ra_conf:
+                if 'esp_group' not in ipsec or ra_conf['esp_group'] not in ipsec['esp_group']:
+                    raise ConfigError(f"Invalid esp-group on {name} remote-access config")
+            else:
+                raise ConfigError(f"Missing esp-group on {name} remote-access config")
+
+            if 'ike_group' in ra_conf:
+                if 'ike_group' not in ipsec or ra_conf['ike_group'] not in ipsec['ike_group']:
+                    raise ConfigError(f"Invalid ike-group on {name} remote-access config")
+            else:
+                raise ConfigError(f"Missing ike-group on {name} remote-access config")
+
+            if 'authentication' not in ra_conf:
+                raise ConfigError(f"Missing authentication on {name} remote-access config")
+
+            if ra_conf['authentication']['server_mode'] == 'x509':
+                if 'x509' not in ra_conf['authentication']:
+                    raise ConfigError(f"Missing x509 settings on {name} remote-access config")
+
+                x509 = ra_conf['authentication']['x509']
+
+                if 'ca_certificate' not in x509 or 'certificate' not in x509:
+                    raise ConfigError(f"Missing x509 certificates on {name} remote-access config")
+
+                verify_pki_x509(ipsec['pki'], x509)
+            elif ra_conf['authentication']['server_mode'] == 'pre-shared-secret':
+                if 'pre_shared_secret' not in ra_conf['authentication']:
+                    raise ConfigError(f"Missing pre-shared-key on {name} remote-access config")
+
+    if 'site_to_site' in ipsec and 'peer' in ipsec['site_to_site']:
+        for peer, peer_conf in ipsec['site_to_site']['peer'].items():
+            has_default_esp = False
+            if 'default_esp_group' in peer_conf:
+                has_default_esp = True
+                if 'esp_group' not in ipsec or peer_conf['default_esp_group'] not in ipsec['esp_group']:
+                    raise ConfigError(f"Invalid esp-group on site-to-site peer {peer}")
+
+            if 'ike_group' in peer_conf:
+                if 'ike_group' not in ipsec or peer_conf['ike_group'] not in ipsec['ike_group']:
+                    raise ConfigError(f"Invalid ike-group on site-to-site peer {peer}")
+            else:
+                raise ConfigError(f"Missing ike-group on site-to-site peer {peer}")
+
+            if 'authentication' not in peer_conf or 'mode' not in peer_conf['authentication']:
+                raise ConfigError(f"Missing authentication on site-to-site peer {peer}")
+
+            if peer_conf['authentication']['mode'] == 'x509':
+                if 'x509' not in peer_conf['authentication']:
+                    raise ConfigError(f"Missing x509 settings on site-to-site peer {peer}")
+
+                x509 = peer_conf['authentication']['x509']
+
+                if 'ca_certificate' not in x509 or 'certificate' not in x509:
+                    raise ConfigError(f"Missing x509 certificates on site-to-site peer {peer}")
+
+                verify_pki_x509(ipsec['pki'], x509)
+            elif peer_conf['authentication']['mode'] == 'rsa':
+                if 'rsa' not in peer_conf['authentication']:
+                    raise ConfigError(f"Missing RSA settings on site-to-site peer {peer}")
+
+                rsa = peer_conf['authentication']['rsa']
+
+                if 'local_key' not in rsa:
+                    raise ConfigError(f"Missing RSA local-key on site-to-site peer {peer}")
+
+                if 'remote_key' not in rsa:
+                    raise ConfigError(f"Missing RSA remote-key on site-to-site peer {peer}")
+
+                verify_pki_rsa(ipsec['pki'], rsa)
+
+            if 'local_address' not in peer_conf and 'dhcp_interface' not in peer_conf:
+                raise ConfigError(f"Missing local-address or dhcp-interface on site-to-site peer {peer}")
+
+            if 'dhcp_interface' in peer_conf:
+                dhcp_interface = peer_conf['dhcp_interface']
+
+                verify_interface_exists(dhcp_interface)
+
+                if not os.path.exists(f'{DHCP_BASE}_{dhcp_interface}.conf'):
+                    raise ConfigError(f"Invalid dhcp-interface on site-to-site peer {peer}")
+
+                address = get_dhcp_address(dhcp_interface)
+                count = 0
+                while not address and count < dhcp_wait_attempts:
+                    address = get_dhcp_address(dhcp_interface)
+                    count += 1
+                    sleep(dhcp_wait_sleep)
+
+                if not address:
+                    ipsec['dhcp_no_address'][peer] = dhcp_interface
+                    print(f"Failed to get address from dhcp-interface on site-to-site peer {peer} -- skipped")
+                    continue
+
+            if 'vti' in peer_conf:
+                if 'local_address' in peer_conf and 'dhcp_interface' in peer_conf:
+                    raise ConfigError(f"A single local-address or dhcp-interface is required when using VTI on site-to-site peer {peer}")
+
+                if 'bind' in peer_conf['vti']:
+                    vti_interface = peer_conf['vti']['bind']
+                    if not os.path.exists(f'/sys/class/net/{vti_interface}'):
+                        raise ConfigError(f'VTI interface {vti_interface} for site-to-site peer {peer} does not exist!')
+
+            if 'vti' not in peer_conf and 'tunnel' not in peer_conf:
+                raise ConfigError(f"No VTI or tunnel specified on site-to-site peer {peer}")
+
+            if 'tunnel' in peer_conf:
+                for tunnel, tunnel_conf in peer_conf['tunnel'].items():
+                    if 'esp_group' not in tunnel_conf and not has_default_esp:
+                        raise ConfigError(f"Missing esp-group on tunnel {tunnel} for site-to-site peer {peer}")
+
+                    esp_group_name = tunnel_conf['esp_group'] if 'esp_group' in tunnel_conf else peer_conf['default_esp_group']
+
+                    if esp_group_name not in ipsec['esp_group']:
+                        raise ConfigError(f"Invalid esp-group on tunnel {tunnel} for site-to-site peer {peer}")
+
+                    esp_group = ipsec['esp_group'][esp_group_name]
+
+                    if 'mode' in esp_group and esp_group['mode'] == 'transport':
+                        if 'protocol' in tunnel_conf and ((peer in ['any', '0.0.0.0']) or ('local_address' not in peer_conf or peer_conf['local_address'] in ['any', '0.0.0.0'])):
+                            raise ConfigError(f"Fixed local-address or peer required when a protocol is defined with ESP transport mode on tunnel {tunnel} for site-to-site peer {peer}")
+
+                        if ('local' in tunnel_conf and 'prefix' in tunnel_conf['local']) or ('remote' in tunnel_conf and 'prefix' in tunnel_conf['remote']):
+                            raise ConfigError(f"Local/remote prefix cannot be used with ESP transport mode on tunnel {tunnel} for site-to-site peer {peer}")
+
+def cleanup_pki_files():
+    for path in [CERT_PATH, CA_PATH, CRL_PATH, KEY_PATH, PUBKEY_PATH]:
+        if not os.path.exists(path):
+            continue
+        for file in os.listdir(path):
+            file_path = os.path.join(path, file)
+            if os.path.isfile(file_path):
+                os.unlink(file_path)
+
+def generate_pki_files_x509(pki, x509_conf):
+    ca_cert_name = x509_conf['ca_certificate']
+    ca_cert_data = dict_search_args(pki, 'ca', ca_cert_name, 'certificate')
+    ca_cert_crls = dict_search_args(pki, 'ca', ca_cert_name, 'crl') or []
+    crl_index = 1
+
+    cert_name = x509_conf['certificate']
+    cert_data = dict_search_args(pki, 'certificate', cert_name, 'certificate')
+    key_data = dict_search_args(pki, 'certificate', cert_name, 'private', 'key')
+    protected = 'passphrase' in x509_conf
+
+    with open(os.path.join(CA_PATH, f'{ca_cert_name}.pem'), 'w') as f:
+        f.write(wrap_certificate(ca_cert_data))
+
+    for crl in ca_cert_crls:
+        with open(os.path.join(CRL_PATH, f'{ca_cert_name}_{crl_index}.pem'), 'w') as f:
+            f.write(wrap_crl(crl))
+        crl_index += 1
+
+    with open(os.path.join(CERT_PATH, f'{cert_name}.pem'), 'w') as f:
+        f.write(wrap_certificate(cert_data))
+
+    with open(os.path.join(KEY_PATH, f'x509_{cert_name}.pem'), 'w') as f:
+        f.write(wrap_private_key(key_data, protected))
+
+def generate_pki_files_rsa(pki, rsa_conf):
+    local_key_name = rsa_conf['local_key']
+    local_key_data = dict_search_args(pki, 'key_pair', local_key_name, 'private', 'key')
+    protected = 'passphrase' in rsa_conf
+    remote_key_name = rsa_conf['remote_key']
+    remote_key_data = dict_search_args(pki, 'key_pair', remote_key_name, 'public', 'key')
+
+    local_key = load_private_key(local_key_data, rsa_conf['passphrase'] if protected else None)
+
+    with open(os.path.join(KEY_PATH, f'rsa_{local_key_name}.pem'), 'w') as f:
+        f.write(wrap_private_key(local_key_data, protected))
+
+    with open(os.path.join(PUBKEY_PATH, f'{local_key_name}.pem'), 'w') as f:
+        f.write(encode_public_key(local_key.public_key()))
+
+    with open(os.path.join(PUBKEY_PATH, f'{remote_key_name}.pem'), 'w') as f:
+        f.write(wrap_public_key(remote_key_data))
+
+def generate(ipsec):
+    cleanup_pki_files()
+
+    if not ipsec:
+        for config_file in [ipsec_conf, ipsec_secrets, charon_dhcp_conf, interface_conf, swanctl_conf]:
+            if os.path.isfile(config_file):
+                os.unlink(config_file)
+        render(charon_conf, 'ipsec/charon.tmpl', {'install_routes': default_install_routes})
+        return
+
+    if ipsec['dhcp_no_address']:
+        with open(DHCP_HOOK_IFLIST, 'w') as f:
+            f.write(" ".join(ipsec['dhcp_no_address'].values()))
+
+    for path in [swanctl_dir, CERT_PATH, CA_PATH, CRL_PATH, PUBKEY_PATH]:
+        if not os.path.exists(path):
+            os.mkdir(path, mode=0o755)
+
+    if not os.path.exists(KEY_PATH):
+        os.mkdir(KEY_PATH, mode=0o700)
+
+    if ipsec['l2tp']:
+        if 'authentication' in ipsec['l2tp'] and 'x509' in ipsec['l2tp']['authentication']:
+            generate_pki_files_x509(ipsec['pki'], ipsec['l2tp']['authentication']['x509'])
+
+    if 'remote_access' in ipsec:
+        for rw, rw_conf in ipsec['remote_access'].items():
+            if 'authentication' in rw_conf and 'x509' in rw_conf['authentication']:
+                generate_pki_files_x509(ipsec['pki'], rw_conf['authentication']['x509'])
+
+    if 'site_to_site' in ipsec and 'peer' in ipsec['site_to_site']:
+        for peer, peer_conf in ipsec['site_to_site']['peer'].items():
+            if peer in ipsec['dhcp_no_address']:
+                continue
+
+            if peer_conf['authentication']['mode'] == 'x509':
+                generate_pki_files_x509(ipsec['pki'], peer_conf['authentication']['x509'])
+            elif peer_conf['authentication']['mode'] == 'rsa':
+                generate_pki_files_rsa(ipsec['pki'], peer_conf['authentication']['rsa'])
+
+            local_ip = ''
+            if 'local_address' in peer_conf:
+                local_ip = peer_conf['local_address']
+            elif 'dhcp_interface' in peer_conf:
+                local_ip = get_dhcp_address(peer_conf['dhcp_interface'])
+
+            ipsec['site_to_site']['peer'][peer]['local_address'] = local_ip
+
+            if 'tunnel' in peer_conf:
+                for tunnel, tunnel_conf in peer_conf['tunnel'].items():
+                    local_prefixes = dict_search_args(tunnel_conf, 'local', 'prefix')
+                    remote_prefixes = dict_search_args(tunnel_conf, 'remote', 'prefix')
+
+                    if not local_prefixes or not remote_prefixes:
+                        continue
+
+                    passthrough = []
+
+                    for local_prefix in local_prefixes:
+                        for remote_prefix in remote_prefixes:
+                            local_net = ipaddress.ip_network(local_prefix)
+                            remote_net = ipaddress.ip_network(remote_prefix)
+                            if local_net.overlaps(remote_net):
+                                passthrough.append(local_prefix)
+
+                    ipsec['site_to_site']['peer'][peer]['tunnel'][tunnel]['passthrough'] = passthrough
+
+
+    render(ipsec_conf, 'ipsec/ipsec.conf.tmpl', ipsec)
+    render(ipsec_secrets, 'ipsec/ipsec.secrets.tmpl', ipsec)
+    render(charon_conf, 'ipsec/charon.tmpl', ipsec)
+    render(charon_dhcp_conf, 'ipsec/charon/dhcp.conf.tmpl', ipsec)
+    render(interface_conf, 'ipsec/interfaces_use.conf.tmpl', ipsec)
+    render(swanctl_conf, 'ipsec/swanctl.conf.tmpl', ipsec)
+
+def resync_nhrp(ipsec):
+    if ipsec and not ipsec['nhrp_exists']:
+        return
+
+    tmp = run('/usr/libexec/vyos/conf_mode/protocols_nhrp.py')
+    if tmp > 0:
+        print('ERROR: failed to reapply NHRP settings!')
+
+def wait_for_vici_socket(timeout=5, sleep_interval=0.1):
+    start_time = time()
+    test_command = f'sudo socat -u OPEN:/dev/null UNIX-CONNECT:{vici_socket}'
+    while True:
+        if (start_time + timeout) < time():
+            return None
+        result = run(test_command)
+        if result == 0:
+            return True
+        sleep(sleep_interval)
+
+def apply(ipsec):
+    if not ipsec:
+        call('sudo ipsec stop')
+    else:
+        args = ''
+        if 'auto_update' in ipsec:
+            args = '--auto-update ' + ipsec['auto_update']
+        call(f'sudo ipsec restart {args}')
+        call('sudo ipsec rereadall')
+        call('sudo ipsec reload')
+
+        if wait_for_vici_socket():
+            call('sudo swanctl -q')
+
+    resync_nhrp(ipsec)
+
+if __name__ == '__main__':
+    try:
+        ipsec = get_config()
+        verify(ipsec)
+        generate(ipsec)
+        apply(ipsec)
+    except ConfigError as e:
+        print(e)
+        exit(1)