pki: eapol: T4245: Add full CA and client cert chains to wpa_supplicant PEM files

This commit updates the eapol code so that it writes the full
certificate chains for both the specified CA and the client certificate
to `<iface>_ca.pem` and `<iface>_cert.pem`, respectively.

The full CA chain is necessary for validating the incoming server
certificate when it is signed by an intermediate CA and the
intermediate CA cert is not included in the EAP-TLS ServerHello. In this
scenario, wpa_supplicant needs to have both the intermediate CA and the
root CA in its `ca_file`.

Similarly, the full client certificate chain is needed when the ISP
expects/requires that the client (wpa_supplicant) sends the client cert
+ the intermediate CA (or even + the root CA) as part of the EAP-TLS
ClientHello.

Signed-off-by: Andrew Gunnerson <chillermillerlong@hotmail.com>

1 files changed, 15 insertions, 3 deletions

diff --git a/src/conf_mode/interfaces-ethernet.py b/src/conf_mode/interfaces-ethernet.py
index ab8d58f81..2a8a126f2 100755
--- a/src/conf_mode/interfaces-ethernet.py
+++ b/src/conf_mode/interfaces-ethernet.py
@@ -32,7 +32,9 @@ from vyos.configverify import verify_vlan_config
 from vyos.configverify import verify_vrf
 from vyos.ethtool import Ethtool
 from vyos.ifconfig import EthernetIf
-from vyos.pki import wrap_certificate
+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 render
 from vyos.util import call
@@ -159,7 +161,14 @@ def generate(ethernet):
         cert_name = ethernet['eapol']['certificate']
         pki_cert = ethernet['pki']['certificate'][cert_name]
 
-        write_file(cert_file_path, wrap_certificate(pki_cert['certificate']))
+        loaded_pki_cert = load_certificate(pki_cert['certificate'])
+        loaded_ca_certs = {load_certificate(c['certificate'])
+            for c in ethernet['pki']['ca'].values()}
+
+        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 ethernet['eapol']:
@@ -167,8 +176,11 @@ def generate(ethernet):
             ca_cert_name = ethernet['eapol']['ca_certificate']
             pki_ca_cert = ethernet['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)
+
             write_file(ca_cert_file_path,
-                       wrap_certificate(pki_ca_cert['certificate']))
+                       '\n'.join(encode_certificate(c) for c in ca_full_chain))
     else:
         # delete configuration on interface removal
         if os.path.isfile(wpa_suppl_conf.format(**ethernet)):