pppoe: T3621: validate that both username and password are set

A validator is missing checking that if authentication is used on a PPPoE
interface, both username and password are set.

(cherry picked from commit 0361c3ac449f183476f7aee31439417d9f7f8012)

1 files changed, 13 insertions, 0 deletions

diff --git a/python/vyos/configverify.py b/python/vyos/configverify.py
index 88cbf2d5b..979e28b11 100644
--- a/python/vyos/configverify.py
+++ b/python/vyos/configverify.py
@@ -166,6 +166,19 @@ def verify_mirror(config):
                 raise ConfigError(f'Can not mirror "{direction}" traffic back ' \
                                    'the originating interface!')
 
+def verify_authentication(config):
+    """
+    Common helper function used by interface implementations to perform
+    recurring validation of authentication for either PPPoE or WWAN interfaces.
+
+    If authentication CLI option is defined, both username and password must
+    be set!
+    """
+    if 'authentication' not in config:
+        return
+    if not {'user', 'password'} <= set(config['authentication']):
+        raise ConfigError('Authentication requires both username and ' \
+                          'password to be set!')
 
 def verify_address(config):
     """