wireguard: T4774: Prevent duplicate peer public keys

2 files changed, 15 insertions, 2 deletions

diff --git a/smoketest/scripts/cli/test_interfaces_wireguard.py b/smoketest/scripts/cli/test_interfaces_wireguard.py
index f3e9670f7..14fc8d109 100755
--- a/smoketest/scripts/cli/test_interfaces_wireguard.py
+++ b/smoketest/scripts/cli/test_interfaces_wireguard.py
@@ -62,10 +62,10 @@ class WireGuardInterfaceTest(VyOSUnitTestSHIM.TestCase):
 
             self.assertTrue(os.path.isdir(f'/sys/class/net/{intf}'))
 
-
     def test_wireguard_add_remove_peer(self):
         # T2939: Create WireGuard interfaces with associated peers.
         # Remove one of the configured peers.
+        # T4774: Test prevention of duplicate peer public keys
         interface = 'wg0'
         port = '12345'
         privkey = '6ISOkASm6VhHOOSz/5iIxw+Q9adq9zA17iMM4X40dlc='
@@ -80,11 +80,17 @@ class WireGuardInterfaceTest(VyOSUnitTestSHIM.TestCase):
         self.cli_set(base_path + [interface, 'peer', 'PEER01', 'allowed-ips', '10.205.212.10/32'])
         self.cli_set(base_path + [interface, 'peer', 'PEER01', 'address', '192.0.2.1'])
 
-        self.cli_set(base_path + [interface, 'peer', 'PEER02', 'public-key', pubkey_2])
+        self.cli_set(base_path + [interface, 'peer', 'PEER02', 'public-key', pubkey_1])
         self.cli_set(base_path + [interface, 'peer', 'PEER02', 'port', port])
         self.cli_set(base_path + [interface, 'peer', 'PEER02', 'allowed-ips', '10.205.212.11/32'])
         self.cli_set(base_path + [interface, 'peer', 'PEER02', 'address', '192.0.2.2'])
 
+        # Duplicate pubkey_1
+        with self.assertRaises(ConfigSessionError):
+            self.cli_commit()
+
+        self.cli_set(base_path + [interface, 'peer', 'PEER02', 'public-key', pubkey_2])
+
         # Commit peers
         self.cli_commit()
 
diff --git a/src/conf_mode/interfaces-wireguard.py b/src/conf_mode/interfaces-wireguard.py
index 8d738f55e..762bad94f 100755
--- a/src/conf_mode/interfaces-wireguard.py
+++ b/src/conf_mode/interfaces-wireguard.py
@@ -87,6 +87,8 @@ def verify(wireguard):
                                'cannot be used for the interface!')
 
     # run checks on individual configured WireGuard peer
+    public_keys = []
+
     for tmp in wireguard['peer']:
         peer = wireguard['peer'][tmp]
 
@@ -100,6 +102,11 @@ def verify(wireguard):
             raise ConfigError('Both Wireguard port and address must be defined '
                               f'for peer "{tmp}" if either one of them is set!')
 
+        if peer['public_key'] in public_keys:
+            raise ConfigError(f'Duplicate public-key defined on peer "{tmp}"')
+
+        public_keys.append(peer['public_key'])
+
 def apply(wireguard):
     tmp = WireGuardIf(wireguard['ifname'])
     if 'deleted' in wireguard: