1 files changed, 371 insertions, 0 deletions
diff --git a/src/etc/opennhrp/opennhrp-script.py b/src/etc/opennhrp/opennhrp-script.py
new file mode 100644
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--- /dev/null
+++ b/src/etc/opennhrp/opennhrp-script.py
@@ -0,0 +1,371 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2021-2023 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 os
+import re
+import sys
+import vyos.ipsec
+
+from json import loads
+from pathlib import Path
+
+from vyos.logger import getLogger
+from vyos.utils.process import cmd
+from vyos.utils.process import process_named_running
+
+NHRP_CONFIG: str = '/run/opennhrp/opennhrp.conf'
+
+
+def vici_get_ipsec_uniqueid(conn: str, src_nbma: str,
+                            dst_nbma: str) -> list[str]:
+    """ Find and return IKE SAs by src nbma and dst nbma
+
+    Args:
+        conn (str): a connection name
+        src_nbma (str): an IP address of NBMA source
+        dst_nbma (str): an IP address of NBMA destination
+
+    Returns:
+        list: a list of IKE connections that match a criteria
+    """
+    if not conn or not src_nbma or not dst_nbma:
+        logger.error(
+            f'Incomplete input data for resolving IKE unique ids: '
+            f'conn: {conn}, src_nbma: {src_nbma}, dst_nbma: {dst_nbma}')
+        return []
+
+    try:
+        logger.info(
+            f'Resolving IKE unique ids for: conn: {conn}, '
+            f'src_nbma: {src_nbma}, dst_nbma: {dst_nbma}')
+        list_ikeid: list[str] = []
+        list_sa: list = vyos.ipsec.get_vici_sas_by_name(conn, None)
+        for sa in list_sa:
+            if sa[conn]['local-host'].decode('ascii') == src_nbma \
+                    and sa[conn]['remote-host'].decode('ascii') == dst_nbma:
+                list_ikeid.append(sa[conn]['uniqueid'].decode('ascii'))
+        return list_ikeid
+    except Exception as err:
+        logger.error(f'Unable to find unique ids for IKE: {err}')
+        return []
+
+
+def vici_ike_terminate(list_ikeid: list[str]) -> bool:
+    """Terminating IKE SAs by list of IKE IDs
+
+    Args:
+        list_ikeid (list[str]): a list of IKE ids to terminate
+
+    Returns:
+        bool: result of termination action
+    """
+    if not list:
+        logger.warning('An empty list for termination was provided')
+        return False
+
+    try:
+        vyos.ipsec.terminate_vici_ikeid_list(list_ikeid)
+        return True
+    except Exception as err:
+        logger.error(f'Failed to terminate SA for IKE ids {list_ikeid}: {err}')
+        return False
+
+
+def parse_type_ipsec(interface: str) -> tuple[str, str]:
+    """Get DMVPN Type and NHRP Profile from the configuration
+
+    Args:
+        interface (str): a name of interface
+
+    Returns:
+        tuple[str, str]: `peer_type` and `profile_name`
+    """
+    if not interface:
+        logger.error('Cannot find peer type - no input provided')
+        return '', ''
+
+    config_file: str = Path(NHRP_CONFIG).read_text()
+    regex: str = rf'^interface {interface} #(?P<peer_type>hub|spoke) ?(?P<profile_name>[^\n]*)$'
+    match = re.search(regex, config_file, re.M)
+    if match:
+        return match.groupdict()['peer_type'], match.groupdict()[
+            'profile_name']
+    return '', ''
+
+
+def add_peer_route(nbma_src: str, nbma_dst: str, mtu: str) -> None:
+    """Add a route to a NBMA peer
+
+    Args:
+        nbma_src (str): a local IP address
+        nbma_dst (str): a remote IP address
+        mtu (str): a MTU for a route
+    """
+    logger.info(f'Adding route from {nbma_src} to {nbma_dst} with MTU {mtu}')
+    # Find routes to a peer
+    route_get_cmd: str = f'sudo ip --json route get {nbma_dst} from {nbma_src}'
+    try:
+        route_info_data = loads(cmd(route_get_cmd))
+    except Exception as err:
+        logger.error(f'Unable to find a route to {nbma_dst}: {err}')
+        return
+
+    # Check if an output has an expected format
+    if not isinstance(route_info_data, list):
+        logger.error(
+            f'Garbage returned from the "{route_get_cmd}" '
+            f'command: {route_info_data}')
+        return
+
+    # Add static routes to a peer
+    for route_item in route_info_data:
+        route_dev = route_item.get('dev')
+        route_dst = route_item.get('dst')
+        route_gateway = route_item.get('gateway')
+        # Prepare a command to add a route
+        route_add_cmd = 'sudo ip route add'
+        if route_dst:
+            route_add_cmd = f'{route_add_cmd} {route_dst}'
+        if route_gateway:
+            route_add_cmd = f'{route_add_cmd} via {route_gateway}'
+        if route_dev:
+            route_add_cmd = f'{route_add_cmd} dev {route_dev}'
+        route_add_cmd = f'{route_add_cmd} proto 42 mtu {mtu}'
+        # Add a route
+        try:
+            cmd(route_add_cmd)
+        except Exception as err:
+            logger.error(
+                f'Unable to add a route using command "{route_add_cmd}": '
+                f'{err}')
+
+
+def vici_initiate(conn: str, child_sa: str, src_addr: str,
+                  dest_addr: str) -> bool:
+    """Initiate IKE SA connection with specific peer
+
+    Args:
+        conn (str): an IKE connection name
+        child_sa (str): a child SA profile name
+        src_addr (str): NBMA local address
+        dest_addr (str): NBMA address of a peer
+
+    Returns:
+        bool: a result of initiation command
+    """
+    logger.info(
+        f'Trying to initiate connection. Name: {conn}, child sa: {child_sa}, '
+        f'src_addr: {src_addr}, dst_addr: {dest_addr}')
+    try:
+        vyos.ipsec.vici_initiate(conn, child_sa, src_addr, dest_addr)
+        return True
+    except Exception as err:
+        logger.error(f'Unable to initiate connection {err}')
+        return False
+
+
+def vici_terminate(conn: str, src_addr: str, dest_addr: str) -> None:
+    """Find and terminate IKE SAs by local NBMA and remote NBMA addresses
+
+    Args:
+        conn (str): IKE connection name
+        src_addr (str): NBMA local address
+        dest_addr (str): NBMA address of a peer
+    """
+    logger.info(
+        f'Terminating IKE connection {conn} between {src_addr} '
+        f'and {dest_addr}')
+
+    ikeid_list: list[str] = vici_get_ipsec_uniqueid(conn, src_addr, dest_addr)
+
+    if not ikeid_list:
+        logger.warning(
+            f'No active sessions found for IKE profile {conn}, '
+            f'local NBMA {src_addr}, remote NBMA {dest_addr}')
+    else:
+        try:
+            vyos.ipsec.terminate_vici_ikeid_list(ikeid_list)
+        except Exception as err:
+            logger.error(
+                f'Failed to terminate SA for IKE ids {ikeid_list}: {err}')
+
+def iface_up(interface: str) -> None:
+    """Proceed tunnel interface UP event
+
+    Args:
+        interface (str): an interface name
+    """
+    if not interface:
+        logger.warning('No interface name provided for UP event')
+
+    logger.info(f'Turning up interface {interface}')
+    try:
+        cmd(f'sudo ip route flush proto 42 dev {interface}')
+        cmd(f'sudo ip neigh flush dev {interface}')
+    except Exception as err:
+        logger.error(
+            f'Unable to flush route on interface "{interface}": {err}')
+
+
+def peer_up(dmvpn_type: str, conn: str) -> None:
+    """Proceed NHRP peer UP event
+
+    Args:
+        dmvpn_type (str): a type of peer
+        conn (str): an IKE profile name
+    """
+    logger.info(f'Peer UP event for {dmvpn_type} using IKE profile {conn}')
+    src_nbma = os.getenv('NHRP_SRCNBMA')
+    dest_nbma = os.getenv('NHRP_DESTNBMA')
+    dest_mtu = os.getenv('NHRP_DESTMTU')
+
+    if not src_nbma or not dest_nbma:
+        logger.error(
+            f'Can not get NHRP NBMA addresses: local {src_nbma}, '
+            f'remote {dest_nbma}')
+        return
+
+    logger.info(f'NBMA addresses: local {src_nbma}, remote {dest_nbma}')
+    if dest_mtu:
+        add_peer_route(src_nbma, dest_nbma, dest_mtu)
+    if conn and dmvpn_type == 'spoke' and process_named_running('charon'):
+        vici_terminate(conn, src_nbma, dest_nbma)
+        vici_initiate(conn, 'dmvpn', src_nbma, dest_nbma)
+
+
+def peer_down(dmvpn_type: str, conn: str) -> None:
+    """Proceed NHRP peer DOWN event
+
+    Args:
+        dmvpn_type (str): a type of peer
+        conn (str): an IKE profile name
+    """
+    logger.info(f'Peer DOWN event for {dmvpn_type} using IKE profile {conn}')
+
+    src_nbma = os.getenv('NHRP_SRCNBMA')
+    dest_nbma = os.getenv('NHRP_DESTNBMA')
+
+    if not src_nbma or not dest_nbma:
+        logger.error(
+            f'Can not get NHRP NBMA addresses: local {src_nbma}, '
+            f'remote {dest_nbma}')
+        return
+
+    logger.info(f'NBMA addresses: local {src_nbma}, remote {dest_nbma}')
+    if conn and dmvpn_type == 'spoke' and process_named_running('charon'):
+        vici_terminate(conn, src_nbma, dest_nbma)
+    try:
+        cmd(f'sudo ip route del {dest_nbma} src {src_nbma} proto 42')
+    except Exception as err:
+        logger.error(
+            f'Unable to del route from {src_nbma} to {dest_nbma}: {err}')
+
+
+def route_up(interface: str) -> None:
+    """Proceed NHRP route UP event
+
+    Args:
+        interface (str): an interface name
+    """
+    logger.info(f'Route UP event for interface {interface}')
+
+    dest_addr = os.getenv('NHRP_DESTADDR')
+    dest_prefix = os.getenv('NHRP_DESTPREFIX')
+    next_hop = os.getenv('NHRP_NEXTHOP')
+
+    if not dest_addr or not dest_prefix or not next_hop:
+        logger.error(
+            f'Can not get route details: dest_addr {dest_addr}, '
+            f'dest_prefix {dest_prefix}, next_hop {next_hop}')
+        return
+
+    logger.info(
+        f'Route details: dest_addr {dest_addr}, dest_prefix {dest_prefix}, '
+        f'next_hop {next_hop}')
+
+    try:
+        cmd(f'sudo ip route replace {dest_addr}/{dest_prefix} proto 42 \
+                via {next_hop} dev {interface}')
+        cmd('sudo ip route flush cache')
+    except Exception as err:
+        logger.error(
+            f'Unable replace or flush route to {dest_addr}/{dest_prefix} '
+            f'via {next_hop} dev {interface}: {err}')
+
+
+def route_down(interface: str) -> None:
+    """Proceed NHRP route DOWN event
+
+    Args:
+        interface (str): an interface name
+    """
+    logger.info(f'Route DOWN event for interface {interface}')
+
+    dest_addr = os.getenv('NHRP_DESTADDR')
+    dest_prefix = os.getenv('NHRP_DESTPREFIX')
+
+    if not dest_addr or not dest_prefix:
+        logger.error(
+            f'Can not get route details: dest_addr {dest_addr}, '
+            f'dest_prefix {dest_prefix}')
+        return
+
+    logger.info(
+        f'Route details: dest_addr {dest_addr}, dest_prefix {dest_prefix}')
+    try:
+        cmd(f'sudo ip route del {dest_addr}/{dest_prefix} proto 42')
+        cmd('sudo ip route flush cache')
+    except Exception as err:
+        logger.error(
+            f'Unable delete or flush route to {dest_addr}/{dest_prefix}: '
+            f'{err}')
+
+
+if __name__ == '__main__':
+    logger = getLogger('opennhrp-script', syslog=True)
+    logger.debug(
+        f'Running script with arguments: {sys.argv}, '
+        f'environment: {os.environ}')
+
+    action = sys.argv[1]
+    interface = os.getenv('NHRP_INTERFACE')
+
+    if not interface:
+        logger.error('Can not get NHRP interface name')
+        sys.exit(1)
+
+    dmvpn_type, profile_name = parse_type_ipsec(interface)
+    if not dmvpn_type:
+        logger.info(f'Interface {interface} is not NHRP tunnel')
+        sys.exit()
+
+    dmvpn_conn: str = ''
+    if profile_name:
+        dmvpn_conn: str = f'dmvpn-{profile_name}-{interface}'
+    if action == 'interface-up':
+        iface_up(interface)
+    elif action == 'peer-register':
+        pass
+    elif action == 'peer-up':
+        peer_up(dmvpn_type, dmvpn_conn)
+    elif action == 'peer-down':
+        peer_down(dmvpn_type, dmvpn_conn)
+    elif action == 'route-up':
+        route_up(interface)
+    elif action == 'route-down':
+        route_down(interface)
+
+    sys.exit()