ipsec: T2816: IPSec python rework, includes DMVPN and VTI support

1 files changed, 409 insertions, 15 deletions

diff --git a/src/conf_mode/vpn_ipsec.py b/src/conf_mode/vpn_ipsec.py
index 969266c30..a1c36ea3b 100755
--- a/src/conf_mode/vpn_ipsec.py
+++ b/src/conf_mode/vpn_ipsec.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 #
-# Copyright (C) 2020 VyOS maintainers and contributors
+# 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
@@ -16,52 +16,446 @@
 
 import os
 
+from copy import deepcopy
+from subprocess import DEVNULL
 from sys import exit
+from time import sleep
 
 from vyos.config import Config
+from vyos.configdiff import ConfigDiff
 from vyos.template import render
-from vyos.util import call
-from vyos.util import dict_search
+from vyos.util import call, get_interface_address, process_named_running, run, cidr_fit
 from vyos import ConfigError
 from vyos import airbag
-from pprint import pprint
 airbag.enable()
 
+authby_translate = {
+    'pre-shared-secret': 'secret',
+    'rsa': 'rsasig',
+    'x509': 'rsasig'
+}
+default_pfs = 'dh-group2'
+pfs_translate = {
+    'dh-group1': 'modp768',
+    'dh-group2': 'modp1024',
+    'dh-group5': 'modp1536',
+    'dh-group14': 'modp2048',
+    'dh-group15': 'modp3072',
+    'dh-group16': 'modp4096',
+    'dh-group17': 'modp6144',
+    'dh-group18': 'modp8192',
+    'dh-group19': 'ecp256',
+    'dh-group20': 'ecp384',
+    'dh-group21': 'ecp512',
+    'dh-group22': 'modp1024s160',
+    'dh-group23': 'modp2048s224',
+    'dh-group24': 'modp2048s256',
+    'dh-group25': 'ecp192',
+    'dh-group26': 'ecp224',
+    'dh-group27': 'ecp224bp',
+    'dh-group28': 'ecp256bp',
+    'dh-group29': 'ecp384bp',
+    'dh-group30': 'ecp512bp',
+    'dh-group31': 'curve25519',
+    'dh-group32': 'curve448'
+}
+
+ike_ciphers = {}
+esp_ciphers = {}
+
+marks = {}
+mark_base = 0x900000
+mark_index = 1
+
+CA_PATH = "/etc/ipsec.d/cacerts"
+CRL_PATH = "/etc/ipsec.d/crls"
+
+DHCP_BASE = "/var/lib/dhcp/dhclient"
+
+LOCAL_KEY_PATHS = ['/config/auth/', '/config/ipsec.d/rsa-keys/']
+X509_PATH = '/config/auth/'
+
+conf = None
+
+def resync_l2tp(conf):
+    if not conf.exists('vpn l2tp remote-access ipsec-settings '):
+        return
+
+    tmp = run('/usr/libexec/vyos/conf_mode/ipsec-settings.py')
+    if tmp > 0:
+        print('ERROR: failed to reapply L2TP IPSec settings!')
+
+def resync_nhrp(conf):
+    if not conf.exists('protocols nhrp tunnel'):
+        return
+
+    run('/opt/vyatta/sbin/vyos-update-nhrp.pl --set_ipsec')
+
 def get_config(config=None):
+    global conf
     if config:
         conf = config
     else:
         conf = Config()
-    base = ['vpn', 'nipsec']
+    base = ['vpn', 'ipsec']
     if not conf.exists(base):
         return None
 
     # retrieve common dictionary keys
-    ipsec = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
+    ipsec = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True, no_tag_node_value_mangle=True)
+
+    default_ike_pfs = None
+
+    if 'ike_group' in ipsec:
+        for group, ike_conf in ipsec['ike_group'].items():
+            if 'proposal' in ike_conf:
+                ciphers = []
+                for i in ike_conf['proposal']:
+                    proposal = ike_conf['proposal'][i]
+                    enc = proposal['encryption'] if 'encryption' in proposal else None
+                    hash = proposal['hash'] if 'hash' in proposal else None
+                    pfs = ('dh-group' + proposal['dh_group']) if 'dh_group' in proposal else default_pfs
+
+                    if not default_ike_pfs:
+                        default_ike_pfs = pfs
+
+                    if enc and hash:
+                        ciphers.append(f"{enc}-{hash}-{pfs_translate[pfs]}" if pfs else f"{enc}-{hash}")
+                ike_ciphers[group] = ','.join(ciphers) + '!'
+
+    if 'esp_group' in ipsec:
+        for group, esp_conf in ipsec['esp_group'].items():
+            pfs = esp_conf['pfs'] if 'pfs' in esp_conf else 'enable'
+
+            if pfs == 'disable':
+                pfs = None
+
+            if pfs == 'enable':
+                pfs = default_ike_pfs
+            
+            if 'proposal' in esp_conf:
+                ciphers = []
+                for i in esp_conf['proposal']:
+                    proposal = esp_conf['proposal'][i]
+                    enc = proposal['encryption'] if 'encryption' in proposal else None
+                    hash = proposal['hash'] if 'hash' in proposal else None
+                    if enc and hash:
+                        ciphers.append(f"{enc}-{hash}-{pfs_translate[pfs]}" if pfs else f"{enc}-{hash}")
+                esp_ciphers[group] = ','.join(ciphers) + '!'
+
     return ipsec
 
 def verify(ipsec):
     if not ipsec:
         return None
 
+    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 '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}")
+
+                if 'key' not in peer_conf['authentication']['x509'] or 'ca_cert_file' not in peer_conf['authentication']['x509'] or 'cert_file' not in peer_conf['authentication']['x509']:
+                    raise ConfigError(f"Missing x509 settings on site-to-site peer {peer}")
+
+                if 'file' not in peer_conf['authentication']['x509']['key']:
+                    raise ConfigError(f"Missing x509 settings on site-to-site peer {peer}")
+
+                for key in ['ca_cert_file', 'cert_file', 'crl_file']:
+                    if key in peer_conf['authentication']['x509']:
+                        path = peer_conf['authentication']['x509'][key]
+                        if not os.path.exists(path if path.startswith(X509_PATH) else (X509_PATH + path)):
+                            raise ConfigError(f"File not found for {key} on site-to-site peer {peer}")
+
+                key_path = peer_conf['authentication']['x509']['key']['file']
+                if not os.path.exists(key_path if key_path.startswith(X509_PATH) else (X509_PATH + key_path)):
+                    raise ConfigError(f"Private key not found on site-to-site peer {peer}")
+
+            if peer_conf['authentication']['mode'] == 'rsa':
+                if not verify_rsa_local_key():
+                    raise ConfigError(f"Invalid key on rsa-keys local-key")
+
+                if 'rsa_key_name' not in peer_conf['authentication']:
+                    raise ConfigError(f"Missing rsa-key-name on site-to-site peer {peer}")
+
+                if not verify_rsa_key(peer_conf['authentication']['rsa_key_name']):
+                    raise ConfigError(f"Invalid rsa-key-name on site-to-site peer {peer}")
+
+            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']
+                if not os.path.exists(f'{DHCP_BASE}_{dhcp_interface}.conf'):
+                    raise ConfigError(f"Invalid dhcp-interface on site-to-site peer {peer}")
+
+            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 get_vti_interface(vti_interface):
+                        raise ConfigError(f'Invalid VTI interface on site-to-site peer {peer}')
+
+            if 'vti' not in peer_conf and 'tunnel' not in peer_conf:
+                raise ConfigError(f"No vti or tunnels 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 get_rsa_local_key():
+    global conf
+    base = ['vpn', 'rsa-keys']
+    if not conf.exists(base + ['local-key', 'file']):
+        return False
+
+    return conf.return_value(base + ['local-key', 'file'])
+
+def verify_rsa_local_key():
+    file = get_rsa_local_key()
+
+    if not file:
+        return False
+
+    for path in LOCAL_KEY_PATHS:
+        if os.path.exists(path + file):
+            return path + file
+
+    return False
+
+def verify_rsa_key(key_name):
+    global conf
+    base = ['vpn', 'rsa-keys']
+    if not conf.exists(base):
+        return False
+    return conf.exists(base + ['rsa-key-name', key_name, 'rsa-key'])
+
 def generate(ipsec):
-    if not ipsec:
-        return None
+    data = {}
 
-    return ipsec
+    if ipsec:
+        data = deepcopy(ipsec)
+
+        if 'site_to_site' in data and 'peer' in data['site_to_site']:
+            for peer, peer_conf in ipsec['site_to_site']['peer'].items():
+                if peer_conf['authentication']['mode'] == 'x509':
+                    ca_cert_file = peer_conf['authentication']['x509']['ca_cert_file']
+                    crl_file = peer_conf['authentication']['x509']['crl_file'] if 'crl_file' in peer_conf['authentication']['x509'] else None
+
+                    if not ca_cert_file.startswith(X509_PATH):
+                        ca_cert_file = (X509_PATH + ca_cert_file)
+
+                    if crl_file and not crl_file.startswith(X509_PATH):
+                        crl_file = (X509_PATH + crl_file)
+
+                    call(f'cp -f {ca_cert_file} {CA_PATH}/')
+                    if crl_file:
+                        call(f'cp -f {crl_file} {CRL_PATH}/')
+
+                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'])
+
+                data['site_to_site']['peer'][peer]['local_address'] = local_ip
+
+                if 'vti' in peer_conf and 'bind' in peer_conf['vti']:
+                    vti_interface = peer_conf['vti']['bind']
+                    get_mark(vti_interface)
+                else:
+                    for tunnel, tunnel_conf in peer_conf['tunnel'].items():
+                        if ('local' not in tunnel_conf or 'prefix' not in tunnel_conf['local']) or ('remote' not in tunnel_conf or 'prefix' not in tunnel_conf['remote']):
+                            continue
+                        local_prefix = tunnel_conf['local']['prefix']
+                        remote_prefix = tunnel_conf['remote']['prefix']
+                        passthrough = cidr_fit(local_prefix, remote_prefix)
+                        data['site_to_site']['peer'][peer]['tunnel'][tunnel]['passthrough'] = passthrough
+
+        data['authby'] = authby_translate
+        data['ciphers'] = {'ike': ike_ciphers, 'esp': esp_ciphers}
+        data['marks'] = marks
+        data['rsa_local_key'] = verify_rsa_local_key()
+        data['x509_path'] = X509_PATH
+
+        if 'logging' in ipsec and 'log_modes' in ipsec['logging']:
+            modes = ipsec['logging']['log_modes']
+            level = ipsec['logging']['log_level'] if 'log_level' in ipsec['logging'] else '1'
+            if isinstance(modes, str): modes = [modes]
+            if 'any' in modes:
+                modes = ['dmn', 'mgr', 'ike', 'chd', 'job', 'cfg', 'knl', 'net', 'asn', 'enc', 'lib', 'esp', 'tls', 'tnc', 'imc', 'imv', 'pts']
+            data['charondebug'] = f' {level}, '.join(modes) + ' ' + level
+
+    render("/etc/ipsec.conf", "ipsec/ipsec.conf.tmpl", data)
+    render("/etc/ipsec.secrets", "ipsec/ipsec.secrets.tmpl", data)
+    render("/etc/swanctl/swanctl.conf", "ipsec/swanctl.conf.tmpl", data)
 
 def apply(ipsec):
     if not ipsec:
-        return None
+        if conf.exists('vpn l2tp '):
+            call('sudo /usr/sbin/ipsec rereadall')
+            call('sudo /usr/sbin/ipsec reload')
+            call('sudo /usr/sbin/swanctl -q')
+        else:
+            call('sudo /usr/sbin/ipsec stop')
+        cleanup_vti_interfaces()
+        resync_l2tp(conf)
+        resync_nhrp(conf)
+        return
+
+    diff = ConfigDiff(conf, key_mangling=('-', '_'))
+    diff.set_level(['vpn', 'ipsec'])
+
+    old_if, new_if = diff.get_value_diff(['ipsec-interfaces', 'interface'])
+    interface_change = (old_if != new_if)
+
+    should_start = ('profile' in ipsec or ('site_to_site' in ipsec and 'peer' in ipsec['site_to_site']))
+
+    if should_start:
+        apply_vti_interfaces(ipsec)
+    else:
+        cleanup_vti_interfaces()
+
+    if not process_named_running('charon'):
+        args = ''
+        if 'auto_update' in ipsec:
+            args = f'--auto-update {ipsec["auto_update"]}'
+
+        if should_start:
+            call(f'sudo /usr/sbin/ipsec start {args}')
+    else:
+        if not should_start:
+            call('sudo /usr/sbin/ipsec stop')
+        elif interface_change:
+            call('sudo /usr/sbin/ipsec restart')
+        else:
+            call('sudo /usr/sbin/ipsec rereadall')
+            call('sudo /usr/sbin/ipsec reload')
+
+    if should_start:
+        sleep(2) # Give charon enough time to start
+        call('sudo /usr/sbin/swanctl -q')
 
-    pprint(ipsec)
+    resync_l2tp(conf)
+    resync_nhrp(conf)
+
+def apply_vti_interfaces(ipsec):
+    # While vyatta-vti-config.pl is still active, this interface will get deleted by cleanupVtiNotConfigured()
+    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 'vti' in peer_conf and 'bind' in peer_conf['vti']:
+                vti_interface = peer_conf['vti']['bind']
+                vti_conf = get_vti_interface(vti_interface)
+                if not vti_conf:
+                    continue
+                vti_mtu = vti_conf['mtu'] if 'mtu' in vti_conf else 1500
+                mark = get_mark(vti_interface)
+
+                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'])
+
+                call(f'sudo /usr/sbin/ip link delete {vti_interface} type vti', stderr=DEVNULL)
+                call(f'sudo /usr/sbin/ip link add {vti_interface} type vti local {local_ip} remote {peer} okey {mark} ikey {mark}')
+                call(f'sudo /usr/sbin/ip link set {vti_interface} mtu {vti_mtu}')
+                if 'address' in vti_conf:
+                    address = vti_conf['address']
+                    if isinstance(address, list):
+                        for addr in address:
+                            call(f'sudo /usr/sbin/ip addr add {addr} dev {vti_interface}')
+                    else:
+                        call(f'sudo /usr/sbin/ip addr add {address} dev {vti_interface}')
+
+                if 'description' in vti_conf:
+                    description = vti_conf['description']
+                    call(f'sudo echo "{description}" > /sys/class/net/{vti_interface}/ifalias')
+
+def get_vti_interface(vti_interface):
+    global conf
+    section = conf.get_config_dict(['interfaces', 'vti'], get_first_key=True)
+    for interface, interface_conf in section.items():
+        if interface == vti_interface:
+            return interface_conf
+    return None
+
+def cleanup_vti_interfaces():
+    global conf
+    section = conf.get_config_dict(['interfaces', 'vti'], get_first_key=True)
+    for interface, interface_conf in section.items():
+        call(f'sudo /usr/sbin/ip link delete {interface} type vti', stderr=DEVNULL)
+
+def get_mark(vti_interface):
+    global mark_base, mark_index
+    if vti_interface not in marks:
+        marks[vti_interface] = mark_base + mark_index
+        mark_index += 1
+    return marks[vti_interface]
+
+def get_dhcp_address(interface):
+    addr = get_interface_address(interface)
+    if not addr:
+        return None
+    if len(addr['addr_info']) == 0:
+        return None
+    return addr['addr_info'][0]['local']
 
 if __name__ == '__main__':
     try:
-        c = get_config()
-        verify(c)
-        generate(c)
-        apply(c)
+        ipsec = get_config()
+        verify(ipsec)
+        generate(ipsec)
+        apply(ipsec)
     except ConfigError as e:
         print(e)
         exit(1)