interface-names: T3869: add vyos_interface_rescan

1 files changed, 206 insertions, 0 deletions

diff --git a/src/helpers/vyos-interface-rescan.py b/src/helpers/vyos-interface-rescan.py
new file mode 100755
index 000000000..1ac1810e0
--- /dev/null
+++ b/src/helpers/vyos-interface-rescan.py
@@ -0,0 +1,206 @@
+#!/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 os
+import stat
+import argparse
+import logging
+import netaddr
+
+from vyos.configtree import ConfigTree
+from vyos.defaults import directories
+from vyos.util import get_cfg_group_id
+
+debug = False
+
+vyos_udev_dir = directories['vyos_udev_dir']
+vyos_log_dir = directories['log']
+log_file = os.path.splitext(os.path.basename(__file__))[0]
+vyos_log_file = os.path.join(vyos_log_dir, log_file)
+
+logger = logging.getLogger(__name__)
+handler = logging.FileHandler(vyos_log_file, mode='a')
+formatter = logging.Formatter('%(levelname)s: %(message)s')
+handler.setFormatter(formatter)
+logger.addHandler(handler)
+
+passlist = {
+    '02:07:01' : 'Interlan',
+    '02:60:60' : '3Com',
+    '02:60:8c' : '3Com',
+    '02:a0:c9' : 'Intel',
+    '02:aa:3c' : 'Olivetti',
+    '02:cf:1f' : 'CMC',
+    '02:e0:3b' : 'Prominet',
+    '02:e6:d3' : 'BTI',
+    '52:54:00' : 'Realtek',
+    '52:54:4c' : 'Novell 2000',
+    '52:54:ab' : 'Realtec',
+    'e2:0c:0f' : 'Kingston Technologies'
+}
+
+def is_multicast(addr: netaddr.eui.EUI) -> bool:
+    return bool(addr.words[0] & 0b1)
+
+def is_locally_administered(addr: netaddr.eui.EUI) -> bool:
+    return bool(addr.words[0] & 0b10)
+
+def is_on_passlist(hwid: str) -> bool:
+    top = hwid.rsplit(':', 3)[0]
+    if top in list(passlist):
+        return True
+    return False
+
+def is_persistent(hwid: str) -> bool:
+    addr = netaddr.EUI(hwid)
+    if is_multicast(addr):
+        return False
+    if is_locally_administered(addr) and not is_on_passlist(hwid):
+        return False
+    return True
+
+def get_wireless_physical_device(intf: str) -> str:
+    if 'wlan' not in intf:
+        return ''
+    try:
+        tmp = os.readlink(f'/sys/class/net/{intf}/phy80211')
+    except OSError:
+        logger.critical(f"Failed to read '/sys/class/net/{intf}/phy80211'")
+        return ''
+    phy = os.path.basename(tmp)
+    logger.info(f"wireless phy is {phy}")
+    return phy
+
+def get_interface_type(intf: str) -> str:
+    if 'eth' in intf:
+        intf_type = 'ethernet'
+    elif 'wlan' in intf:
+        intf_type = 'wireless'
+    else:
+        logger.critical('Unrecognized interface type!')
+        intf_type = ''
+    return intf_type
+
+def get_new_interfaces() -> dict:
+    """ Read any new interface data left in /run/udev/vyos by vyos_net_name
+    """
+    interfaces = {}
+
+    for intf in os.listdir(vyos_udev_dir):
+        path = os.path.join(vyos_udev_dir, intf)
+        try:
+            with open(path) as f:
+                hwid = f.read().rstrip()
+        except OSError as e:
+            logger.error(f"OSError {e}")
+            continue
+        interfaces[intf] = hwid
+
+    # reverse sort to simplify insertion in config
+    interfaces = {key: value for key, value in sorted(interfaces.items(),
+                                                      reverse=True)}
+    return interfaces
+
+def filter_interfaces(intfs: dict) -> dict:
+    """ Ignore no longer existing interfaces or non-persistent mac addresses
+    """
+    filtered = {}
+
+    for intf, hwid in intfs.items():
+        if not os.path.isdir(os.path.join('/sys/class/net', intf)):
+            continue
+        if not is_persistent(hwid):
+            continue
+        filtered[intf] = hwid
+
+    return filtered
+
+def interface_rescan(config_path: str):
+    """ Read new data and update config file
+    """
+    interfaces = get_new_interfaces()
+
+    logger.debug(f"interfaces from udev: {interfaces}")
+
+    interfaces = filter_interfaces(interfaces)
+
+    logger.debug(f"filtered interfaces: {interfaces}")
+
+    try:
+        with open(config_path) as f:
+            config_file = f.read()
+    except OSError as e:
+        logger.critical(f"OSError {e}")
+        exit(1)
+
+    config = ConfigTree(config_file)
+
+    for intf, hwid in interfaces.items():
+        logger.info(f"Writing '{intf}' '{hwid}' to config file")
+        intf_type = get_interface_type(intf)
+        if not intf_type:
+            continue
+        if not config.exists(['interfaces', intf_type]):
+            config.set(['interfaces', intf_type])
+            config.set_tag(['interfaces', intf_type])
+        config.set(['interfaces', intf_type, intf, 'hw-id'], value=hwid)
+
+        if intf_type == 'wireless':
+            phy = get_wireless_physical_device(intf)
+            if not phy:
+                continue
+            config.set(['interfaces', intf_type, intf, 'physical-device'],
+                       value=phy)
+
+    try:
+        with open(config_path, 'w') as f:
+            f.write(config.to_string())
+    except OSError as e:
+        logger.critical(f"OSError {e}")
+
+def main():
+    global debug
+
+    argparser = argparse.ArgumentParser(
+        formatter_class=argparse.RawTextHelpFormatter)
+    argparser.add_argument('configfile', type=str)
+    argparser.add_argument('--debug', action='store_true')
+    args = argparser.parse_args()
+
+    if args.debug:
+        debug = True
+        logger.setLevel(logging.DEBUG)
+    else:
+        logger.setLevel(logging.INFO)
+
+    configfile = args.configfile
+
+    # preserve vyattacfg group write access to running config
+    os.setgid(get_cfg_group_id())
+    os.umask(0o002)
+
+    # log file perms are not automatic; this could be cleaner by moving to a
+    # logging config file
+    os.chown(vyos_log_file, 0, get_cfg_group_id())
+    os.chmod(vyos_log_file,
+             stat.S_IRUSR | stat.S_IWUSR | stat.S_IRGRP | stat.S_IWGRP | stat.S_IROTH)
+
+    interface_rescan(configfile)
+
+if __name__ == '__main__':
+    main()