bond: T6709: add EAPoL support (backport #4069) (#4076)

* ethernet: T6709: move EAPoL support to common framework

Instead of having EAPoL (Extensible Authentication Protocol over Local Area
Network) support only available for ethernet interfaces, move this to common
ground at vyos.ifconfig.interface making it available for all sorts of
interfaces by simply including the XML portion

  #include <include/interface/eapol.xml.i>

(cherry picked from commit 0ee8d5e35044e7480dac6a23e92d43744b8c5d36)

* bond: T6709: add EAPoL support

(cherry picked from commit 8eeb1bdcdfc104ffa77531f270a38cda2aee7f82)

---------

Co-authored-by: Christian Breunig <christian@breunig.cc>

2 files changed, 85 insertions, 4 deletions

diff --git a/python/vyos/configverify.py b/python/vyos/configverify.py
index 59b67300d..92996f2ee 100644
--- a/python/vyos/configverify.py
+++ b/python/vyos/configverify.py
@@ -520,3 +520,20 @@ def verify_pki_dh_parameters(config: dict, dh_name: str, min_key_size: int=0):
         dh_bits = dh_numbers.p.bit_length()
         if dh_bits < min_key_size:
             raise ConfigError(f'Minimum DH key-size is {min_key_size} bits!')
+
+def verify_eapol(config: dict):
+    """
+    Common helper function used by interface implementations to perform
+    recurring validation of EAPoL configuration.
+    """
+    if 'eapol' not in config:
+        return
+
+    if 'certificate' not in config['eapol']:
+        raise ConfigError('Certificate must be specified when using EAPoL!')
+
+    verify_pki_certificate(config, config['eapol']['certificate'], no_password_protected=True)
+
+    if 'ca_certificate' in config['eapol']:
+        for ca_cert in config['eapol']['ca_certificate']:
+            verify_pki_ca_certificate(config, ca_cert)
diff --git a/python/vyos/ifconfig/interface.py b/python/vyos/ifconfig/interface.py
index 72d3d3afe..31fcf6ca6 100644
--- a/python/vyos/ifconfig/interface.py
+++ b/python/vyos/ifconfig/interface.py
@@ -32,6 +32,12 @@ from vyos.configdict import list_diff
 from vyos.configdict import dict_merge
 from vyos.configdict import get_vlan_ids
 from vyos.defaults import directories
+from vyos.pki import find_chain
+from vyos.pki import encode_certificate
+from vyos.pki import load_certificate
+from vyos.pki import wrap_private_key
+from vyos.template import is_ipv4
+from vyos.template import is_ipv6
 from vyos.template import render
 from vyos.utils.network import mac2eui64
 from vyos.utils.dict import dict_search
@@ -41,9 +47,8 @@ from vyos.utils.network import get_vrf_tableid
 from vyos.utils.network import is_netns_interface
 from vyos.utils.process import is_systemd_service_active
 from vyos.utils.process import run
-from vyos.template import is_ipv4
-from vyos.template import is_ipv6
 from vyos.utils.file import read_file
+from vyos.utils.file import write_file
 from vyos.utils.network import is_intf_addr_assigned
 from vyos.utils.network import is_ipv6_link_local
 from vyos.utils.assertion import assert_boolean
@@ -52,7 +57,6 @@ from vyos.utils.assertion import assert_mac
 from vyos.utils.assertion import assert_mtu
 from vyos.utils.assertion import assert_positive
 from vyos.utils.assertion import assert_range
-
 from vyos.ifconfig.control import Control
 from vyos.ifconfig.vrrp import VRRP
 from vyos.ifconfig.operational import Operational
@@ -377,6 +381,9 @@ class Interface(Control):
         >>> i = Interface('eth0')
         >>> i.remove()
         """
+        # Stop WPA supplicant if EAPoL was in use
+        if is_systemd_service_active(f'wpa_supplicant-wired@{self.ifname}'):
+            self._cmd(f'systemctl stop wpa_supplicant-wired@{self.ifname}')
 
         # remove all assigned IP addresses from interface - this is a bit redundant
         # as the kernel will remove all addresses on interface deletion, but we
@@ -1522,6 +1529,61 @@ class Interface(Control):
             return None
         self.set_interface('per_client_thread', enable)
 
+    def set_eapol(self) -> None:
+        """ Take care about EAPoL supplicant daemon """
+
+        # XXX: wpa_supplicant works on the source interface
+        cfg_dir = '/run/wpa_supplicant'
+        wpa_supplicant_conf = f'{cfg_dir}/{self.ifname}.conf'
+        eapol_action='stop'
+
+        if 'eapol' in self.config:
+            # The default is a fallback to hw_id which is not present for any interface
+            # other then an ethernet interface. Thus we emulate hw_id by reading back the
+            # Kernel assigned MAC address
+            if 'hw_id' not in self.config:
+                self.config['hw_id'] = read_file(f'/sys/class/net/{self.ifname}/address')
+            render(wpa_supplicant_conf, 'ethernet/wpa_supplicant.conf.j2', self.config)
+
+            cert_file_path = os.path.join(cfg_dir, f'{self.ifname}_cert.pem')
+            cert_key_path = os.path.join(cfg_dir, f'{self.ifname}_cert.key')
+
+            cert_name = self.config['eapol']['certificate']
+            pki_cert = self.config['pki']['certificate'][cert_name]
+
+            loaded_pki_cert = load_certificate(pki_cert['certificate'])
+            loaded_ca_certs = {load_certificate(c['certificate'])
+                for c in self.config['pki']['ca'].values()} if 'ca' in self.config['pki'] else {}
+
+            cert_full_chain = find_chain(loaded_pki_cert, loaded_ca_certs)
+
+            write_file(cert_file_path,
+                    '\n'.join(encode_certificate(c) for c in cert_full_chain))
+            write_file(cert_key_path, wrap_private_key(pki_cert['private']['key']))
+
+            if 'ca_certificate' in self.config['eapol']:
+                ca_cert_file_path = os.path.join(cfg_dir, f'{self.ifname}_ca.pem')
+                ca_chains = []
+
+                for ca_cert_name in self.config['eapol']['ca_certificate']:
+                    pki_ca_cert = self.config['pki']['ca'][ca_cert_name]
+                    loaded_ca_cert = load_certificate(pki_ca_cert['certificate'])
+                    ca_full_chain = find_chain(loaded_ca_cert, loaded_ca_certs)
+                    ca_chains.append(
+                        '\n'.join(encode_certificate(c) for c in ca_full_chain))
+
+                write_file(ca_cert_file_path, '\n'.join(ca_chains))
+
+            eapol_action='reload-or-restart'
+
+        # start/stop WPA supplicant service
+        self._cmd(f'systemctl {eapol_action} wpa_supplicant-wired@{self.ifname}')
+
+        if 'eapol' not in self.config:
+            # delete configuration on interface removal
+            if os.path.isfile(wpa_supplicant_conf):
+                os.unlink(wpa_supplicant_conf)
+
     def update(self, config):
         """ General helper function which works on a dictionary retrived by
         get_config_dict(). It's main intention is to consolidate the scattered
@@ -1609,7 +1671,6 @@ class Interface(Control):
             tmp = get_interface_config(config['ifname'])
             if 'master' in tmp and tmp['master'] != bridge_if:
                 self.set_vrf('')
-
         else:
             self.set_vrf(config.get('vrf', ''))
 
@@ -1752,6 +1813,9 @@ class Interface(Control):
         value = '1' if (tmp != None) else '0'
         self.set_per_client_thread(value)
 
+        # enable/disable EAPoL (Extensible Authentication Protocol over Local Area Network)
+        self.set_eapol()
+
         # Enable/Disable of an interface must always be done at the end of the
         # derived class to make use of the ref-counting set_admin_state()
         # function. We will only enable the interface if 'up' was called as