1 files changed, 43 insertions, 0 deletions
diff --git a/python/vyos/configverify.py b/python/vyos/configverify.py
index a888791ba..e71e4e1c5 100644
--- a/python/vyos/configverify.py
+++ b/python/vyos/configverify.py
@@ -89,6 +89,49 @@ def verify_vrf(config):
                 'Interface "{ifname}" cannot be both a member of VRF "{vrf}" '
                 'and bridge "{is_bridge_member}"!'.format(**config))
 
+def verify_tunnel(config):
+    """
+    This helper is used to verify the common part of the tunnel
+    """
+    from vyos.template import is_ipv4
+    from vyos.template import is_ipv6
+    
+    if 'encapsulation' not in config:
+        raise ConfigError('Must configure the tunnel encapsulation for '\
+                          '{ifname}!'.format(**config))
+    
+    if 'local_ip' not in config and 'dhcp_interface' not in config:
+        raise ConfigError('local-ip is mandatory for tunnel')
+
+    if 'remote_ip' not in config and config['encapsulation'] != 'gre':
+        raise ConfigError('remote-ip is mandatory for tunnel')
+
+    if {'local_ip', 'dhcp_interface'} <= set(config):
+        raise ConfigError('Can not use both local-ip and dhcp-interface')
+
+    if config['encapsulation'] in ['ipip6', 'ip6ip6', 'ip6gre', 'ip6erspan']:
+        error_ipv6 = 'Encapsulation mode requires IPv6'
+        if 'local_ip' in config and not is_ipv6(config['local_ip']):
+            raise ConfigError(f'{error_ipv6} local-ip')
+
+        if 'remote_ip' in config and not is_ipv6(config['remote_ip']):
+            raise ConfigError(f'{error_ipv6} remote-ip')
+    else:
+        error_ipv4 = 'Encapsulation mode requires IPv4'
+        if 'local_ip' in config and not is_ipv4(config['local_ip']):
+            raise ConfigError(f'{error_ipv4} local-ip')
+
+        if 'remote_ip' in config and not is_ipv4(config['remote_ip']):
+            raise ConfigError(f'{error_ipv4} remote-ip')
+
+    if config['encapsulation'] in ['sit', 'gre-bridge']:
+        if 'source_interface' in config:
+            raise ConfigError('Option source-interface can not be used with ' \
+                              'encapsulation "sit" or "gre-bridge"')
+    elif config['encapsulation'] == 'gre':
+        if 'local_ip' in config and is_ipv6(config['local_ip']):
+            raise ConfigError('Can not use local IPv6 address is for mGRE tunnels')
+
 def verify_eapol(config):
     """
     Common helper function used by interface implementations to perform